— A ANN TALA RAS LLENA ee ы мел PRA LEAR AE tre наанаа VIA uid nd ...! E 2 B 7 ye r ` KT a Е Е Е | E I Ea Е y m E. = 5 = «d END "A mom NM" Е Е ч E = "Y E кч 242 " qe Ua Gl aa M E | aA жЕ DIA mo ы la a E Ар UM u Я МУ i А UN BI rs < pr теа er ұғуы Ға» Wi ДГ Ls A sQ IA > 4 E d был T A Le ХБ КООРТ. E EL: € kA e y" VOLUME XXVII. i d by order of His Excellency the Governor General of India E in Council. M hE OF? 3; cx M т "Occ ТЫ: š ШҮ stu LAX NTC Я LA DAPR үйе. “А ^ i - WE BEC е ras моссоксу II Ie | - Testo ` 2% m A UV | CALCUTTA: н иб : OFFICE ОЕ ТНЕ ‘GEOLOGICAL SURVEY. | EIS EGAN PAUL, TRENCH, EBENEN & Co. ee rog v r£ ORA d it, ИЙ a š “4 IR dim "әр p кез 25 EE LV mr x жа quce CALCUTTA: | ` GOVERN MENT OF INDIA CENTRAL PRINTING OFFICE, 8, HASTINGS STREET, CONTENTS. — Page. ART. I.—On some Marine Fossils from the Miocene of Upper Burma, by | . Dn. Fritz NoETLING, F, С. S., Paleontologist, Geological Survey E e of India . - . А Е . А . А А ° I—45 i i Explanation of Plates . . ° . . a : . dev 3 ` ART. 2.—The Occurrence of Petroleum in Burma, and its technical ex- E ploitation, by Dr. FRITZ NorETLING F. G. S, hy ill s Р i Geological Survey of m 4 E c Part 1.—Historical and Geological . . . . . .47—205 n. CHAPTER 1.—Historical Summary up to 1886. . : . 47—74 A A. Legendary Times . . . А • 47—50 В. Historical Times . ° ° ° . 50—74 CHAPTER 11.—The Occurrence of Petroleum in the Districts of Prome and Thayetmyo . . . . 75—77 | 1. Geographical Position . . . . 75 E i 2, Geological Features . . А Е 75 с. dum 3. Stratigraphical Features " ° ° 77 29 ( 4. Economic Value. . . . . . 27 Ec . CHAPTER IIL —The Occurrence of Petroleum near Minbu. -. 78—94 pec ! I. Geographical Position x ° Р 78 4 2. Geological Features . E Se « 78—79 к A. The Pliocene or Irrawaddi Bee Д 78 | y | B. The Miocene or Pegu Series : 79 | з. Stratigraphical Features © . . . 80 E 4. The Mud Volcanoes . ° . . 81—95 р | r, Situation of the Mud Volcanoes - e 81 E - ^ 2. Detailed description . : : : 82 E A. Southern group . - - : 82 ЕЕ. : В, Middlegroup . . . 7 88 - yos ; C. Northern group . ° ° . 88 E 3. General Features dq e cs 89 Ex. CHAPTER 1V,—The Petroleum field of Yenangyoung „ 4 95—169 А 1. Geographical Position, Area and Physical 3 Geography Е . . - . . 95—98 | A. Beme tract _ . А > E ә 96 | B. Kodoung tract . ° 2 - . 97 $ A a aa 97 а | | D. Physical Сеортарһу. i ; - 9 E 4 ` 2. Geological Features . . . . 100---109 Д А. Diluvium . ° š 100 B. The Tertiary M . e 102—109 di | CONTENTS. Page. I. The Pliocene or Irrawaddi Series 102 2. The Miocene or Pegu Series . 106 (аа) Тһе upper Міосепе ог Yenangyoung Stage. . 106 - (bb) The Lower Моб: ог Рош ше 107 (a) Lithological characters . . 107 (b) Palzontological characters . 108 (с) The Occurrence of Petroleum . 109 . 3. Stratigraphy œ - ° Д ° .123—169 А. General Features ç А . 123 (a) Unequality of clientas . 123 (0 (b) Veins of eruptive mud . х 126 (c) The anticlinal and dome-like struc= | ture. . . . ° 132 (aa) The ai arch ° 132 (bb) The longitudinal arch . 133 B. Superficial sections `. : . 135 С. The sections of the drilled velis rd 137 D. The original sedimentation of the ys X ЛАУ liferous beds . 4 157 E, General conclusions, апа ашы р pects of the Yenangyoung Oil-field . 161 (a) The native reserves . 162 (b) The area exploited by drilled weils - 169 CHAPTER V.—The Occurrence of Petroleum near Yenangyat . 170 1. Geographical Position, Area and Physical Geography + . Д ° ° .178—183 2. Geological Features . . . > . 172 A. The Pliocene or Irrawaddi Series . : 172 B. The Miocene or Pegu Series . . 172 (aa) The Upper Miocene or Yenan- gyoung Stage. ` (bb) The Lower Miocene or TANE | ; Stage - А 174 M - (cc) The Occurrence of ЖТТ T 3. Sie Features . . : . 178 A. The Superficial sections . ° 178—183 - B. The sections of the drilled wells . SS | CHAPTER VI.—The Occurrence of Petroleum at other localities | in Upper Burma. . ЕЛ . . 183 CHAPTER VII.—Relation between the occurrence of petroleum | and the main structural lines of Upper Burma S Pay ° А . .184—188 CHAPTER VIII.—Chemical composition and physical properties 189—205 PaRT 11.—Economic importance of the Oil-fields of Burma . д 206 , CHAPTER I,—The Yenangyoung Oil- field ar ТА . «206--248 2 | | : т. The community of Twinzayos and their his- - | 3 - . tory ° |l. ° ° ° . а 206 “ы = - б m. NS ы ano "m CONTENTS. 2. The Construction of Pit wells 3. The number of wells in the native reserve . A, Period previous to 1888 B. From 1888 to the beginning of 1895 А (аа) Productive wells (1) Depth of pit wells (2) Production of the pit wells . (bb) Unproductive wells (1) Abandoned wells . (2) Wells under construction . | (3) Well sites ° 4. The production of tke pit wells A. Period previous to 1886 B. From 1886 to the end of 1894 5. The drilled wells A. Number and depth of drilled al: - B. Production of the drilled wells 6. Summary of the production of the Yenan- gyoung Oil-field = е ES. II.—The Yenangyat Oil-field . A. Period previous to 1887 . B. From 1886 to the end of 1894 2. The drilled wells CHAPTER 111.—The petroleum production of Burma есте IV.—The cost price and the trade value » N Burmese petroleum ` I, Local consumption of Crude Oil 231 237 237 238 238 240 240 243 245 247 248 251 ° «251—255 ° ° of the 2, Import of Crude Oil from Upper into Lower Burma , ° 23. Export of Petroleum and = Products from Rangoon . LIST OF ILLUSTRATIONS (WOOD-CUTS). Fig. 1. Diagrammatic section through the Minbu Mud Volcanoes from 1886 to 1894 . ° . Diagram showing the mean Tad yield oí petroleum Diagrammatic section showing the sudden change from arenaceous to argillaceous beds, between wells 159 and 161 š Я Diagrammatic ae sawing double tonto abd the first oil sand in the Aungbanyo Diagrammatic section showing the intersection of perpen- dicular, horizontal and diagonal veins of eruptive mud . in miocene sandstone, Taungle-yo east of Beme village Diagrammatic section showing diagonal veins of eruptive mud in miocene sandstone near well 310 Diagrammatic section showing unconformity and horizon- tal veins of eruptive mud in upper miocene sandstone near wells Nos. 530 and 541 ° 2 56—259 251 251 252 255 259—272 264 265 267 iv CONTENTS, Page. Fig. 8. Diagram showing arrangement of the intersecting folds in the Kodoung petroliferous tract + . . А 147 » 9. Oil well diggers, Yenangyoung Oil-field А . a 215 LIST OF PLATES. Frontispiece : Venangyoung Oil-field, Twingon Area, Looking North. Plate 1. Southern Group of Mud Volcanoes, Minbu, in 1889, Looking North ” 3” II. Do. do. Mud . Volcano No. 5, Look- | ing East. III. - Do. do. in 1895, Mud Volcano No. 5, Looking East. IV. Do. do. in 1889, Looking North. V. Mud Stream on No. 5 Mud Volcano. ' vi, ` Do. do. VII. Do. do. VIII. Veins of instrusive mud in the Beme ravine. IX. Yenangyoung Oil-field. View of the eastern slope of the mc poyo. X. Yenangyat Oil-field. View of the eastern slope of the Taungsin Range near Yenangyat. XI. Map of the Distribution of the drilled wells at Kodoung, Yenan- | gyoung Oil-field, ХП. Sections through the Kodoung tract. XIII. Do. do. XIV. Sections through the Yenangyoung Oil-field. XV. Du." ° do. XVI, Sections through the Yenangyat Oil-field. Section near Minbu. Section of Mud volcanoes. XVII. Section of the Bore holes in the МЕНДЕ АЖ Ravine, Yenan- gyat Oil-field, AS 2 MEMOIRS - NT - š x = = ж la , uw Ca س‎ - " g% 7 ,St 3 OLOGICAL SURVEY OF INDIA, - ` "n" Af E as rw fr uc LN 2 , “ к. “er е у E p NWE ci ыы МИР 5 J y -- - ` “ 2 OGICAL SURVEY OF INDIA. - VOLUME XXVII, PART I. Bed. 8р bue ef Bis Excettency ве Governor General of | India in Council, E 3 “ x ` А M "I Eum x em E uw CALCUTTA: pa... 277 OF THE BHORGGICAT'SURVEV . 3E 0 cat , TRENCH, TRÜBNER, & Co. nme As m Ж E IDA Pie. D 4 4? Е à T и í P” £ “ рыс; did 4 1 r; 44 wer тел а ` i E * | ES Tw қ 252 t wi, ç AM А * | CALCUTTA: 00 2 GOVERNMENT OF INDIA CENTRAL PRINTING OFFICE, 8, HASTINGS STREET, Ел MEMOIRS OF THE GEOLOGICAL SURVEY OF INDIA. On some Marine Fossils from the Miocene of Upper Burma, ûy Dr. Fritz Noetling, F. G. S. Paleontologist, Geological Survey of India (with то plates). INTRODUCTION. With the exception of two species, Batissa crawfurdi and Batissa petrolez, which have been collected near Yenangyoung, all the fossils described on the following pages have been collected by me- near Yenangyat and Minbu while surveying the oil-bearing tracts in Upper Burma. It may perhaps seem inadvisable to select the fauna of these two localities for description, considering that large collec- tions of fossils from the miocene of Lower Burma, made by Messrs, Theobald and Fedden are waiting to be described, and that it would be preferable to describe the Upper Burma fossils together with those. This being, however, a task which will occupy several years, and as it appeared necessary to arrive at a more definite conclusion regarding the age of the petroleum-bearing strata, I thought it well worth to examine this fauna and to describe it in a separate paper, and [ am glad to say that the result has fully justified the expectations, ` The geological position of the strata in which these fossils have been found, may be defined in a few words: Batissa crawfurdi and Batissa petrolei have been found in the ferruginous conglomerate or the zone of Hippotherium antelopinum near Yenangyoung ; it is un- questionable that this horizon is younger than that in which the fossils from Minbu and Yenangyat have been found. The latter came from strata which are immediately above the oil-bearing beds сай Yenangyat, and perhaps а couple of hundred feet above the same Memoirs of the Geological Survey of India, Vol. XXVII. Pt.ı. p 64 B' 2 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. strata at Minbu. Now, as we know that the oil-bearing strata are above the beds with Velates schmideliana, Chemn. sp. which are correlative to the Khirthar group in Western India, we must be able to fix the age of the oil-bearing strata, if we succeed in deter- mining with some accuracy the age of the fauna immediately above it. For this purpose the marine fauna from Yenangyat and Minbu would afford valuable support, without anticipating in any way the results of a description of the large collections above mentioned, On the following pages altogether 69 species have been described, which have been partly collected at Minbu and partly at Yenangyat ; only two come from Yenangyoung. The fauna consists of 2 species of Corals, 14 species of Pelecypoda, 45 species of Gastropoda, 3 species of Crustacea and 5 species of Pisces. The Gastropoda therefore exceed the other classes by a considerable number of species, On the whole the character of the fauna is that of one living in shallow water near a sandy beach. | Out of a total of 69 species, 51 have specifically been determined, while from the balance of 18, with some probability, 2 could be referred to species already known, but of 16 the genus only could be determined. For the purposes above mentioned, only the 51 specifically deter- mined species can be made use of ; now out of these the ME B3 species are new: I. Nucula alcocki spec. nov, 13. Sigaretus bicostatus spec. nove 2, Astarte (9) dubia. „ ` » 14. Cassis @archiaci е A 3. Batissa erawfurdi ,, Ж 15. Cassidaria dubia va Ж 24 » Petrolei T » 16. 5 minbuensis p й s. Tellina hilli » a 17. Ficula theobaldi РЕ si 6. ә kingi E M .18. Triton pardalis à A 7. Trochus buddha „ С ,, 19. Fasciolaria feddeni * iis 8. А blanfordi ,, `: y 20. Murex arrakanesis Я, M 9. Dismhelix minuta ,, ” 21. Volgaria birmanica E 10. Scalaria birmanica y, » 22. Pleurotoma irravadica ,, M EE- p irreg ularis ,, » 23. = yenanensis 12. Calyptrea rugosa ,, » ! Records of the Geological Survey of India, vol. xxvii, page 101. (2) INTRODUCTION. | 3 "These species, although they may be found afterwards somewhere else in Burma or in India, are for the present of ho use in ascertaining the | age of the strata in which théy occur, and they may therefore be left alone. As regards the 28 species which have previously Беей described, they are the following :— i. Paracyathus éeruleus, Duncan | . Recent, 2. Eupsammia regalis, Alcock: ^. « i. р 3. ‚Daphoderma celata, Reeve ets a = _to Khirtar group (2). 4 Corbula harpa, Sow, а А ° Ranikot group, 5. Solarium affine, Sow. . Л 8 : e Nari groap. 6. , éydostomum, Menke . . Recent to Nari group. ` 4. Stalaria subtenuilamella, d’Arch. А «бај group. ` 8. Turitella afinis, d'Arch +. Р "a ə Магі group: 9. Natica obscura, Sow. . m ° . 4. Сај group, 10. + Ag callosa, Sow. .... se, ... er ir @ Uncertain. 11. Strombus. nodosus, бом. « . = . Gaj group. 12. Cyprza gra iti, VArch. . e“. . Nari group. | 13. Trivia smithi, К. Martin . . С Miocene (Java). 714. Triton davidsoni, d'Arch. . А ° . Gaj to Nari group. 15. Ranella tubercular is, Lam. . ° Bacal to Miocene (Java). 4 16. Nassa cautleyi, d'Arch. - °. - . Са) group. 17. Clavella djocdjocarte, K. Mart. EL Ss Miocene (Java). . 18. Fasciolaria nodosa, Sow. sp. ° Н . HRanikot group. 19. Murex ‘tchihatchefi, d’ Arch: . . . Uncertain, ` 20. Voluta dentata, Sow. ui. » ° . Магі group. : 21, Oliva djocdjocarta, К. Martin . . . - Miocene (Java). 22. Cancellaria cancellata, Lam. + © Recent to Miocene (Java). ` 23. Terebra fuscata, Broch. . ° = s Miocene. 24, Pleurotoma voyesi, d’Arch. ° . ° Uncertain. 2% » interrupta,Lam. . — . Récenttó Miocene (Java). 26. Conus (Rhisoconus) mallacanus, Hwass. Recent to Miocene (Java). 27. Conus (Leptoconus) marginatus, Sow. 2 • Uncertain, 28. Balanus sublavis, Sow... . . .. + je Gaj group. It may be seen at the first glance that this fauna cannot be consi- dered of any earlier than miocene age ; there are only three species which so far have been noticed to occur in older strata, 222, :— - Dafhoderma celata, Reev, - Corbula harpa, Sow. Fasciolaria nodosa, Sow. 8р, 212 | (3) 4 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. As regards the first species I have convinced myself by comparison with a specimen from the Indian ocean that the tertiary specimen from Burma must be considered identical with it; on the other hand, although I have no specimens of the typical Arca burnesi, d' Arch., for comparison, I am of the opinion that the specimens from Burma must be identical with that species. Mr. Blanford states that Arca burnesí, ` d'Arch., has probably been found in the Khirthar group. At least I ` interpret the query in the column of groups corresponding to this species in this way; we may therefore take it as granted that the exact horizon of Arca burnes? is not yet established, and that it may as well be found in the Nari or Gaj group as not. In fact the latter is more probable, but even if further investigations should prove that Arca burnesi, d'Arch.-Daphoderma caelata, Reeve, should reach as far down as the Khirthar group, no great value could be at to this fact because it is still living in the Indian seas. There remain therefore only two species which have hitherto been found in the Ranikot group only, viz., Corbula harpa, d'Arch. and Fasciolaria nodosa, Sow. Of these two, Corbula harpa, Sow., | from Burma bears a great resemblance to the recent Corbula tunicata from the Indian seas; the latter only differs by the sculpture of the umbonal part of the left valve which is similar to the sculpture of the right valve, while the whole of the left valve i is smooth in the species from Burma, Оп the other hand I. have drawn attention to the fact that the similarity of Corbula harpa, d’Arch., from Sind and of Cordula harpa, from Burma, is not quite absolute; if d'Archiac's figure represents a correct picture of his specimen, I cannot help thinking that the Indian species has coarser. horizontal ribs than the species | from Burma, and that perhaps this difference indicates an evolution- ary character. However, even if Corbula harpa, from Burma is fully identical with the Corbula harpa, d' Archiac, from the [Ranikot group, I do not think that this single species, together with Fasciolaria ] nodosa, could materially affect the views expressed i in regard to. the Miocene character of this fauna. In fact one ought to be rather | surprised that there is not a larger percentage of older forms than two, or at most three species, | 6 4) INTRODUCTION. . 5 The view of the Miocene character of this fauna is further corro- borated by other facts. I stated above that the fauna here described is considerably higher up in the series than the beds with Velates schmideliana, Chemn., and as the latter must be considered as a characteristic fossil of the Khirthar group, it is, 4 priori, reasonable that the strata in which this fauna has been found might be correlated to either the Nari or Gaj groups of India. ` Now we find, in going through the above list, that there are five Species from the Nari group, and five species from the Gaj group, and one species occurring in both; if we were to decide from mere statistics, the question would be difficult to solve, inasmuch as the evidence is equal on both sides. But if we consider that there are seven recent species, and that those found in Java have been found in strata which are equivalent to the Gaj group in India, I think the "balance turns rather in favour of the Gaj than of the Nari group. Until further proof be given to the contrary, I am of opinion there- fore that the series above the petroleum-bearing sands, up to the ferruginous conglomerate of Yenangyoung, and represented by the fauna from Minbu and neat may be correlated with the Gaj group of Western India. A few words remain to be said about the species foreign to the Indian tertiaries, which have been found in the fauna of Yenangyat and Minbu ; there is only one species Terebra fuscata, Brocch, which could be identified with a species from the European tertiary, but seven are identical with species which occur in the Miocene of Java. Deducting these eight species from the total, and further allowing for the two species of Corals,which as far as is known for the present have not been found in India, there remain therefore 18 species which the tertiary beds at Yenangyat and Minbu share with those in Western India. This is rather remarkable, considering that the tertiary beds in Java are much nearer to those in Burma than the latter to the tertiaries of Western India. It would, however, be too rash to form any conclusion from this, or to accept it as an unshake- able fact, inasmuch as the examination of the rich fauna from Lower : 3) 6 NOETLING : MARINE FOSSILS FROM MIOCENE, UPPER BURMA, Burma might considerably alter these results. For the present it will be sufficient to say that the fauna of the miocene beds in Burma consists of ; | MONS . 1. Indigenous species 5 - . - ° ° 2, Indian species . " see ° ° UE A 3, Java species | š 5 s d 2 - é š 7 4» European species . 4 * 4E oe . . I 5. Recent species before not known in a fossil state Е 5 2 TOTAL 5 51 species. In short, it is a fauna which represents a marked Indian facies, slightly sprinkled with a more southern element from Java. DESCRIPTION OF SPECIES. | I. COELENTERATA. E PARACYATHUS C/ERULEUS, Duncan. Ргате I, Fic. 124, . 1889. Paracyathus caeruleus, Duncan, On the Madreporia of the Mergui Archi- - pelago, Journal of the Linnean Soc. Zoology, Vol. XXI, page 5, plate I,figs. 10-11. The corallum is small, with rather a broad base and a constricted stem ; the calice is shallow, elliptical ; marginal. axis nearly i in the same plane; septa in five incomplete circles, very unequal, their sides being largely papillose, neither pali nor columella visible ; costae low sub-equal, narrow and distinctly granular. | | Locality.— Common at Yenangyat, rare at Minbu. | Remarks.—Through the kindness of Dr. Alcock I have been able to compare the fossil species with Prof. Duncan's original, and all I can say is that I found it impossible to discover the slightest difference. For comparison Igive here the figure of the recent Paracyathus caeruleus from the Mergui Archipelago, the specimen not figured in Prof, Duncan's paper, and even the closest examination will fail to show any difference. EUPSAMMIA REGALIS, Alcock. PLATE L Fie. 3—3a. 1893, Eupsammia regalis, Alcock Journ., Asiat. Soc. of Bengal, Vol. LXII, part 2, | page 144, plate V, figs, Sand Sa. | Although none of the specimens under examination are well pre- served, most of them being crushed, I have convinced myself EN Vs oe ii Ë 29 Me | Тер “iqi ү . comparing them with Dr. Alcock's original that the sculpture of the costa is exactly the same, so that there remains no further doubt as PELECYPODA. 7 to the identity. The costae are straight or sometimes a little un- dulating, equal in size and occasionally trifurcating, united at regular ‘intervals across the deep intercostal incisions by horizontal spicules, Locality.—Pretty common at Yenangyat. Remarks.—The living specimen has been dredged in 32 fathoms off Ceylon. | П. PELECYPODA. | ` OSTREA, SP. 1. Only the cast of a medium sized Species has been found ; it IS, however, too ill-preserved to be of any value. ` Locality.—Minbu. | OSTREA, Sp. 2. Another fragment of an oyster has been found at Yenangyat, which certainly belongs to a different species; while the above cast represents a broad species, the Yenangyat specimen must be referred to a narrow and elongated one. It is, however, not sufficiently well preserved to permit a specific definition, | | Locality.—Yenangyat. | PECTEN cf. FAVREL, d'Archiac. 1853. Pecten favrei, d'Archiac and Haime, Desc. des Anim. foss. du groupe nummule itique de I’ Inde, page 270, plate XXIV, figs. 5 and sa. Some fragments of a radially ribbed Pecten might be referred to this species ; they are, however, not well enough preserved to permit an absolutely certain determination ; the character of the ribs and the shape of the valves resemble, however, the above-named species very closely. Locality.—Minbu and Yenangyat. DAPHODERMA CAELATA, Reeve, PLATE I, Fic. 4—44. 1853. Arca burnesi, d'Archiac and Haime, Desc. des Anim, foss. du groupe num. > mulitique de P Inde, page 264, plate X XII, fig. 5 a. b. c. d. The few specimens [under observation are not well preserved but the sculptüre of the valves clearly proves their identity with the 77:50) 8. NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. above-named species. The sculpture consists of fine, flat, radiating ribs of equal strength, which are separated by interstices of about the same breadth. Numerous fine horizontal striae produce a kind of network in the interstices, while the ribs become granular; some of the ribs occasionally bifurcate, but only one of the specimens exhibits this character. Locality, —Pretty rare at Yenangyat. Remarks.— Having compared the fossil specimens with the living Daphoderma caelata, Reeve, I cannot discover any difference be- tween them as regards the sculpture of the shell, and I regard therefore Arca burnest, d' Arch., as identical with the species just mentioned. In a fossil state it seems to have a wide range of distribution, being found in Western India, Burma, Java and Timor. Vertically it probably makes its first appearance in the Khirtar group of Sind. NUCULA ALCOCKI, Spec. nov., PLATE l, Fie. 5—7. The shellis triagonal, considerably longer than high ; the beaks low, depressed, situated in the anterior third of the length; anterior margin short, slightly concave, forming nearly a right angle with the convex ventral margin; dorsal margin straight, meeting the ventral margin at a pointed angle ; hinge consists of sharp transverse teeth : cartilage pit deep and obliquely turned backwards; ventral margin ` crenulated. Surface covered with fine equidistant radiating stria; lunula well defined and covered with a few fine transverse ribs; ; escutcheon less well defined, but covered with one row of short transverse granulations which increase in size from the beak back- | wards, till about two-thirds of the lebt and then again become smaller, Dimensions, Height. VENE ` "Thickness. 12 mm. 17mm. 8mm. : Localíty.—Minbu and Yenangyoung, pretty common. | Remarks.—This pretty species is easily distinguished from. other [3 M^ ve "4 Кее PELECYPODA. - 34 9 species by the peculiar sculpture of the lunula and the escutcheon but it has a very near relative in the living Vucula B Hinds. ASTARTE (P) DUBIA, Spec. nov., PLATE I, Fic. 8—8a. Shell sub- triangular, rather flat, and *moderately inequilateral, The beaks are short but pointed, situated forward of the median line ; anterior side short, posterior side somewhat expanded. Surface covered with fine regular horizontal ribs, which are separated by furrows of equal breadth. Lunula large, but ill-defined, and only limited by a thin line; hinge not known, ا‎ пиар apparently smooth. | -Locality.—Rather rare at Yenangyat. | Remarks.—It is with some doubt that I include this form among the genus Astarte, as the hinge is not known, but so far as can be . judged from the external features, it certainly belongs to the family of Astartidz ; itis quite probable that this form may be found else- where in Burma, and then further details may be given. So far as can be judged, the species is of medium size, as all the specimens under examination do not exceed " mm. in height and ав ` BATISSA CRAWFURDI, Spec. по?., PLATE II, Fie. 1—4; Prate III, Fic. 1—10. ` The shell is cordiform, triangular, thick and inequilateral ; beaks in the anterior third of the length, The anterior margin is round and short, and passes gradually into the ventral margin which is nearly straight; the posterior margin is slightly curved and forms nearly a right angle with the former ; dorsal margin short and curved. Beaks thick, slightly curved inwards, frequently: deeply eroded. Ligament strong ; hinge strongly developed ; there are three cardinal _ teeth in each valve, the anterior one being the shortest and slightly ` inclined backwards; the two following are inclined forwards, the . posterior one being elongated, but thinner than the others. A large compressed anterior and posterior lateral tooth in the left valve, both very finely striated, and fitting into corresponding sockets in the right valve. Surface smooth except some strongly marked striae ( ) - 10 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. of growth, which are rather closely set on the a side, thereby creating a kind of pseudo-ribbing. | | Dimensions, | Е" Height, . Length. Thickness. Largest specimen* . 49mm. 51 (Р) mm, 35 mm. . Average sized specimen. 38 ,,. 40 y 26 y; Locality.—Partly in, but chiefly just above, the zone of Hippo- therium antelopinum, very common, but only locally; for instance ` north-east of Minlindoung any number of specimens might be col- lected. | | Remarks.—The character of the hinge, as well as the general shape and the strongly developed ligament, fix the generic position of this species ; the only doubt which existed was with regard to the lateral teeth, of which there are two only in the left and none in the right valve ; considering, however, the great similarity of this species with the recent Batissa tenebrosa, I think this not sufficient to justify a new genus. Batissa crawfurd? differs from Batissa PER general shape by being (1) more inflated, (2) the beaks being turned more towards the anterior side ; although very marked when numerous specimens arè under examination, it is not always easy to say of a half-grown specimen to which species it belongs. In this regard the hinge _ affords the best distinguishing character, it being always very strongly developed іп Batissa cramfurdi, while that of Batíssa | petrolei is much less powerfully constructed. Besides this charac- ter Batissa crawfurdi can easily be recognised by its thick shell, particularly i in the umbonal part. Batissa crawfurdi has quite a history, so to speak ; although it is known since the year 1829, when it first was mentioned by Crawfurd,? who, to judge from his description, visited the locality which has been marked on my geological map of the Yenangyoung oil-field 1 The posterior side of the above specimen being broken off, the exact length cannot | be given, but to judge from other specimens its length cannot have been less than 51 mm. 2 Crawfurd's Jaurnal of. an Embassy to the „Court of Ava, London, . _1829, page 329. | PELECYPODA, 11 with No. 45. Dr. Buckland! who subsequently described the fossil bones, mentions this fossil as a Cyreza but does not distinguish it by a specific name. Nearly thirty years later the late Dr, Oldham visited Yenangyoung together with the members of tbe mission to Ava, and although he searched for the Cyrena. bed, he could not find it? This is quite intelligible to any one acquainted with the country round Minlindoung, cut up by numerous ravines winding in the most erratic manner, It takes weeks to search for a certain place in this country, the exact location of which is not known.. I only discovered it when systematically mapping the country around Yenangyoung, and so 67 years after its first discovery Cyrena, or as it is now named Batissa crawfurdt, comes to be described. BATISSA PETROLEI, Spec. nov., PLATE II, Fie, 5-50; PLATE ПІ, ` FIG. 2-3. The shell is oval, not very inequilateral, the beak being slightly in front of the median line. The anterior margin is rounded and passes gradually into the slightly curved ventral margin ; the posterior margin is somewhat curved, but does not form such a marked angle with the ventral margin as in Batissa erawfurdi, sp. nov. The beaks are depressed and only slightly inflated ; sometimes they are deeply eroded. Ligament moderately long. Hinge much less strongly developed than in Batissa crawfurdi; arrangement of teeth the same as in the former species, but the cardinal as well as the lateral teeth are much more delicate. The valves are only slightly inflated, rather: thin and covered with strongly та striz of growth, crowding on the anterior side, | | Dimensions. Height. Length. Thickness. 34 mm. 41mm. : 20mm. 37 » 42 n 21 2) ` Locality.—Together with Bassa crawfurdi, but less common at the same place. | ! Crawfurd's Journal of an Embassy to the Court of Ava, London, 1826, Appen- dix XIII, page 85, reprinted from the Transactions of the Geological Society. 2 Yule, Narrative of the Mission to the Court-of Ava, London, 1858, page 315. (nm) “12 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, Remarks.— Although at the first sight the two species of Batissa “here desribed are so similar that it seems nearly impossible to dis- ` tinguish them, a closer examination will at once show the charac- ters by which they differ. There is no difficulty if the hinge is exposed, because the weaker hinge at once distinguishes Batissa petroleí even in fragments, from Batissa crawfurdi with its strong» ly developed teeth; but if the two valves are united, it is not always | easy to say to meh species a single shell might belong ; how. the following features will characterize B. petrolet :— The shell is much less inflated than that of B. crawfurd?. Owing | to beaks being nearer to the median line, and not so much turned forwards, the shell has a more oval shape; the shell is much. thinner than that of В. crawfurdz. If the limits of the two species are drawn as above, there is not the slightest difficulty in keeping them separate, even if fragments only are found. This seems to me very important, because, if I rightly conclude, Mr. Theobold’s Cytherea promensís, the original of ` which I could not find up to the present, must be identical with either B. craufurdi or B. petrolei ; the horizon characterized by these twospecies would therefore aan. be also represented in the tertiary of Lower Burma, VENUS, cf. SCALARIS, Bronn, PLATE ІП, Fie. 4. 1870. Venus scalaris, Hoernes, Die Foss. Moll. d. Tert. Beck. v. Wien. Abhandl.d, k. k. Geol. Reichs. vol. 1V., 1870, page 137, plate XV, fig. 10a-c. An isolated valve, measuring 9. mm. in height, 9 mm. in length, of sub-orbicular shape, probably belongs to this species ; the external characters cannot be seen well, because the surface is covered with sand which cannot be removed without destroying the shell; but it appears that it was covered with sharp, horizontal ribs, separated by broad furrows of about double the breadth of the ribs. A small well defined lunula present; the hinge shows the usual character ; the ventral margin is slightly crenulated inside, Locality—Very rare at Yenangyat. 5 Remarks.—It is unfortunate that only one specimen of this form ( үле ) y T" ر‎ A e hZ veqo ae eee ae Het per І : 4 moy Ww. ange T І ы ” j “ E + CM ' " » . | è PELECYPODA. : $2 | ` 13 has been found, and that even this does not exhibit the characteristic features sufficiently ; but I think that it shows the greatest resem- blance to the above species, which according to Hoernes is very common in the “Тере!” of the Vienna basin. VENUS, sp. Numerous fragments of a shell covered with fine concentric striae | may probably belong to this genus; they are, however, too badly preserved, although they are pretty common, to allow d ue determination. | Locality.— Common at Minbu. TELLINA (TELLINELLA) HILLI, Spec. nov., Prare ІП, Fic. 5—6a. I have before me some fragments of a shell belonging to this genus which exhibit such characteristic features, especially as regards the posterior part of the valve, that notwithstanding their incompleteness, the distinguishing features can be fixed. The shell was fat, triangular in shape; the ventral margin is regularly rounded but slightly cut out towards its posterior end, where it forms a pointed angle with the short straight posterior margin. A sharp 22 keel runs from the beak to the junction of the ventral and posterior margin ; ; and the part thus divided off is marked by a fine sharp furrow in the middle, and a similar sharp keel at the dorsal edge, the latter running from the beak to the upper end of the posterior margin ; the posterior half of the shell is covered with fine, regular horizontal ribs, which pass the radiating keels, where they produce a kind of granulation ; forwards the ribs die out quite suddenly, so that the anterior side is perfectly smooth excepting some strize of Bien ` Locality.—Rare at Yenangyat. Remarks.—It was with some hesitation that I founded a new ` species on so incomplete specimens as those under examination, but the- peculiar character of the surface sculpture justifies this procedure. The nearest fossil form is perhaps Tellina exarata, Sowerby from the Cutch Tertiaries ; this species is, however, very imperfectly known, as according to Mr. Sowerby the surface has been restored. If it was ` the: posterior part which. was preserved in Tellina exarata, the’ 159%.) 24 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. probabilities are that the completion of the anteriór part is not in ас= cordance with the actual character of tlie shell, and that therefore the species from Burma is perhaps identical with that from Cutch, an ase sumption which is well borne out by the character of the posterior side of Tellina exarata. | Another form closely related is Psammobia uniradiata, Brocc, which shows exactly the same characters on the posterior side as Tellina hilli; particularly the undulating stris crossing the keels, which according to Hoernes form one of the chief features of P. uniradiata, are the same as in Tellina hilli; on the other hand there is no doubt that the anterior side of Tellina hilli is smooth, except some fine striz of growth, while in P. uniradıata the whole surface is covered with sharp horizontal ribs. There exist, however, close relations between this and a living species. Í have before me a species which has been dredged at 125 fathoms in the Bay of Bengal and which has been named Tellina murrayi (?) E. A. Smith, which is very closely related to 7. 277, The general shape and the two keels on the posterior sideare the same, but the sculpture is different. In 7. murrayi the keels are smooth, and the sculpture is uniform all over the valves ; in 7. 7 the keels are scaly and the posterior side differs in sculpture from the anterior side by having fine, but sharp horizontal ribs, while the latter only shows irregular striz of growth. However the similiarity between the two species is very striking, and 7. murrayi may perhaps be a descendant from Г. 221/2. 5 TELLINA KINGI, Spec. nov., PLATE IIE Fie, 7—7a. ` All specimens under examination are either. fragments or so ill-preserved that the general shape of the shell cannot be made out ; it seems, however, that it has been of an oval shape ; the characters of the sculpture can, however, be satisfactorily ascertained ; rather a broad but shallow furrow runs from the beak towards the junction of ` ventral and posterior margin, which is accompanied on both sides by- . two moderately strong concave keels. The whole surface is covered. with T dis regular horizontal ribs, which become rather obscure age 5 PELECYPODA. he E 15 on the posterior side behind the furrow, where only strong stria. of growth are seen. ` Locality.— Rare at Yenangyat and Minbu. | Remarks.—The sculpture of the surface distinguishes Tellina kingi at once from Tellina hilli, even in small fragments. A ҰС SOLEN. sp. The posterior fragment of a shell measuring 34 mm. in length and 7 mm, in height exhibits the usual characters of this genus ; but owing to its bad preservation I refrain from giving it a specific name, Localit y.—Very rare at Yenangyat, ` CORBULA HARPA, @’Archiac,, Paté ІП, Fie, 8—8a. 1853. Corbula harpa, d'Archiac and Haime, Descr. des Anim, foss. du groupe nummi- litique de P Inde, page 236, plate XVI, fig. 8, a, b, 9. The shell is inequivalve, the right valve being triangular, but not very inequilateral, inasmuch as the posterior side is only slightly produced; the beak is nearly median, sharp, and strongly rolled in- wards. A fine ridge is running from the beak towards the corner of the ventral and posterior margin; before it the surface is covered with very regular, strong, rounded and horizontal ribs, behind it only. striz of growth may be seen. The left valve is considerably smaller than the right one, triangular in shape, but a little more inequilateral and, except fine striz of growth, perfectly smooth. Dimensions.— Height o mm. Length 1 r mm. Thickness 6 mm, Locality.—Rare at Minbu and Yenangyat, Remarks.—' The specimen of which the measurements are given represents a medium sized one, but as all the larger ones аге in. some way damaged, their measurements could not be given. I mention this because it might appear that the species is of small size while the largest specimen was certainly ofat least double the measure- ments given. The Characters of the Burma species agree so well with Corbula harpa from Western India, that it must be identified with that species, although it seems that the ribs are slightly thinner. Corbula harpa has ышы a near relative in the living Cordula СА i 16 NOETLING : MARINE FOSSILS FROM MIOCENE, UPPER BURMA. tunicata ; the general shape and the sculpture of the right valve are the same, but the left valve of Corbula tunicata shows near the umbonal part a sculpture similar to that of the right valve, while it is perfectly smooth in Corbula harpa. | | IL.—GASTROPODA. TROCHUS BUDDHA, Spec. nov., PLATE IV, Fic. 1—2a. The shell is depressed-pyramidal, perfectly flat on the base; it consists of at least six whorls which increase very slowly in height and are very slightly concave ; suture sharply defined ; earlier whorls perfectly smooth, but on the last, two fine, revolving ribs begin to appear which also extend over the base ; that rib which is closest to | the suture is the strongest and separated from the next by a compara- tively deep and broad furrow ; umbilicus narrow but deep. Aperture unknown. Locality.—Common at Minbu and Yenangyat, Remarks.—This species can be easily distinguished by its apparently smooth surface, because the ribs become frequently obsolete, together with the regularly ribbed base; Trochus buddha seems to be one of the smaller species, as the largest specimen ` measures only 13 mm. diameter by 6 mm, height; those of 11 mm. ` diameter form the majority. TROCHUS BLANFORDI, Spec. nov., PLATE IV, Fic. 3—44. The shell is pyramidal, having a flat, sometimes slightly inflated base; the whorls are low, slightly concave, and show a very pretty and characteristic sculpture; beginning from the suture, there are two keels, like strings of beads, the upper one a little stronger than the lower one, separated by a rounded smooth furrow; above those _ the surface is slightly concave, and there are from two to four revolv- ing lines of very regular small round tubercules, the lowest line of | which is generally the largest. On the base the sculpture consists . of numerous revolving ribs, which look like strings of beads; thinner апа thicker ribs alternate very regularly ; umbilicus very narrow ; aperture unknown. | ( 16 ) uo voc mtn : ` Zu ll = we „u жора а баба әз е. au GASTROPODA. 17 Locality.—Not rare at Minbu and Yenangyat, Remarks.—The peculiar bead-like ornaments distinguish this species easily even in fragments, As regards the arrangement of the ` sculpture, this species seems to be closely related to the living Clancu- lus scabrosus, Phil., from Bombay, but I do not think that both are identical. SOLARIUM AFFINE, Sow., PLATE IV, Fie. 5--ба. EN Solarium affinis, Sowerby, Transact. Geol, Soc, of London, 2nd Ser., Vol. V. 4 pl. XXVI, fig. 5. 1853. . » @Archiac and Haime, Descr, des Anim. foss. du groupe nummulit. de l'Inde, pl. XXVI, fig. 13, a, b, c, fig. 14, a, b, c. The specimens which I collected are not Сй ср well preserved to permit a closer description of this species, which, owing to its relationship with species already known, seems doubtfully indepen- dent. However, the specimens from Burma exhibit such characters | that it appears compulsory to identify it with the Indian Beles | whatever the specific value of that form may be. VE" | "The shell is circular, depressed conical above, slightly convex below. The whorls are angular at the periphery, the suture very indistinct owing to the revolving furrows which mark the upper part ` of the whorls. Umbilicus, narrow, less than one-third of the total | diameter of the shell, strongly crenulated. The sculpture consists, on the upper part of the whorls, of four sharply marked revolving furrows, of which the rst and the 3rd, counting from the suture down- wards, are deeper than the 2nd and the 4th. These are crossed by fine equidistant transverse .striz, which thus produce a kind of granular sculpture just below the suture. On the lower side there are also four revolving furrows,but here two of them are quite close to the peri- phery, while the other two are close to the umbilical edge. Short but ` _ deep furrows radiate from the umbilical edge and produce a granular sculpture on inner part, while the peripheral part remains smooth, Locality .—Minbu and Yenangyat, but rather rare. En | | Caz ) 18 NOETLING : MARINE FOSSILS FROM MIOCENE, UPPER BURMA. Remarks —This species varies a good deal; the specimens from Burma seem to be intermediate between d'Archiac's figs. 13 and. 14; the basis of the Burma specimens perfectly agrees with fig. 148, while the upper side is identical with fig. 13. As regards the general shape, they fully agree with Sowerby’s figure. E The form is apparently a near relative of the living Solarium. per- spectivum, but it seems that the latter has a higher spire, while the | fossil form is more depressed. SOLARIUM CYCLOSTOMUM, Menke, Рілтв IV, Fio. 7—7a. 1853. Solarium euomphaloides, d'Archiac and Haime, Desc. des Anim. foss. du groupe nummulitique de Plnde, page 289, pl. XXVI, fig. 15 a, b, c. One single. specimen of this species has been found, which is however, sufficiently well preserved to permit its determination. The orbicular shell consists of five rounded whorls which are separated by a distinct suture; on the upper side the whorls are flat, and are nearly all lying in one plane. On the lower side they are inflated, form- ing a deep and broad umbilicus, The whole surface is covered with fine revolving ribs which are traversed by oblique striae which by producing small nodules, make the revolving ribs look like strings of minute beads; on the upper side there are 6 to 7, onthe lower side about 9 of these strings; diameter 8 mm, Locality.—Very rare at Minbu, | Remarks.—It seems that the specimens from Burma do not reach the same size as those from India ; this may, however, be an exception | as it is difficult to judge from a single specimen only. On com- | parison with the living Solarzum cyclostomum, Menke, I find that it agrees so well in every way with the fossil ‚Sol. euomphalordes, d' Arch, that the two species must be considered as identical. DISCOHELIX MINUTA, Spec. nov., Prare IV, Fie. 88а, The only specimen which serves for the description is fairly well preserved, although it seems that it is rather crushed in one direction, OES چ _— ASS Í Sa ta SA > 4 "P кет E " “ Ыі Add O A v wA. +2 GASTROPODA, 19 by not being perfectly circuler; it hasa diameter of 7:75 mm, and a height of only 1:75 mm. The shell is slightly concave above, but has apparently a deep umbilicus which is, however, filled up with matrix. The whorls, 7 in number, are all in the same plane, flat above and crenulated at the upper and lower edges. The upper and probably also the lower keel which is in a straight line below the upper one, are slightly crenulated by fine transverse strize, otherwise the whorls are smooth. Locality.—Yenangyat, very rare, Remarks.— Discohelix minuta resembles Discohelix zanclea, Philipps, sp.’ very much, but it differs materially in some points; the fine transverse striz over the keel are apparently much more widely separated in D. minuta than in D. zanclea ; in the latter species they extend to the outer side of the keel, while in the first one they are restricted to the upper side only, further, the outer side of the body whorl shows two distinct fine revolving striae, while it is perfectly smooth in D, minuta. SCALARIA BIRMANICA, Spec. nov., Ртлтв IV, Fic. 9—9a. The shell is turreted, consisting of more than 10 rounded whorls, which are separated by a deep suture ; the ornamentation consists of strong spiral ribs of considerable breadth which slope an teriorly, while _ they are steep behind; the anterior side of the ribs is marked by fine but sharp horizontal striz, which stop abruptly before reaching the - posterior side of the longitudinal ribs; a sharp furrow runs along the base of the whorls, quite close to the suture, so that it is hardly perceptible if the whorls are not separated. Locality .—Not very common at Minbu. Remarks.—The peculiar ornamentation distinguishes this species easily from others. SCALARIA IRREGULARIS, Spec. nov., PLATE V, Fic. 1—2a. The shell consists of rounded whorls which are not closely united but free ; the surface is covered with low longitudinal ribs which are ! Enumeratio Molluscorum Sicilie, vol. II, tab. XXVIII, fig. t1. C2 ( 19 ) 20 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, separated by broad interstices; rather strong revolving lines run across ribs and interstices, (lily producing a kind of reticulated ornamentation. | Locality.—Rare at Minbu. j ` Remarks.— Although the two specimens under examination are rather incomplete, the ornamentation of the surface can be well dis- ` tinguished, and from the characters exhibited we must consider this form a new species. The free whorls, together with the ornamenta- tion, distinguish this species easily from others. SCALARIA SUBTENUILAMELLA, d’Archiac, PLATE, Fic. 3—32. 1853. Scalaria subtenuilamella, d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique de l'Inde, page. 286, plate XXVI, fig. 9 a. Although only one specimen, and even this in a fragmentary condition, has been found, I think that it is sufficient for identification; four whorls are preserved, which show an angular section and are separated by a deep suture. The angular section is produced by three revolving keels, of which, however, only the lowest one is sharply defined, the next one following is only slightly marked, while the third one is stronger; the surface slopes from the third keel towards the suture, between the third and second it is nearly flat and slopes again from the second to the first; as the first keel always coincides with the suture, it is only well seen on the last whorl; the surface is covered with regular sharp longitudinal ribs, obliquely inclined for- wards, which are equidistant and seem to continue from one whorl to ` the other; they are slightly stronger in the middle than towards both | ` ends; although very indistinctly seen, there is no doubt that on the ; base of each whorl ribs and interstices were covered wih very fine regular revolving lines. Locality.—Rare at Minbu. Remarks.—l had some hesitation identifying the specimen reli | Burma with the Indian species, because it seemed to me that they | differed somewhat in general shape; but when comparing the details of ornamentation, I could not help noticing that they are very much the same, although there seems to ex'st some difference which must er GASTROPODA. - 21 3 | be noticed. In the figure of d’Archiac’s Scalaria subtenuilamella, only the rst and 3rd keels are shown, while the 2ndis not to be seen. As this one is however very ill marked, I am rather inclined ` to think that it has been left out by some oversight when the figures were drawn. TURRITELLA AFFINIS, d’Archiac, Prate V, Fic. 4—4a. 1853. а affinis, d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique, de Linde, page 295, plate XXVII, figs. 16, 17, 18, 19. Although very common, only fragments have been found, which = exhibit the characteristic features of this species so well that there can be no doubt as to their identity. The shell is turreted, consisting of nearly plane whorls, which are covered with revolving striae ; so far as could be ascertained they are six in number on the earlier whorls, but gradually increase up to nine; out of these nine - striz the lower three are a little detached from the others, and the first and third counting upwards are of nearly double the thickness of the others; the latter are filiform, equal in strength; only the uppermost = alittle thicker than the remainder ; when well preserved the fine longi- tudinal striæ may be seen in the interstices separating the revolving ` lines. Suture, owing to the peculiar sculpture, not well marked. ` Locality.—Minbu and Yenangyat, pretty common. | Remarks.— According to d'Archiac the sculpture of this species к “а varies a little, but the chief feature of the two strong revolving lines j . atthe base of the whorls is exceedingly well seen in the specimens . 7d from Burma ; the peculiar feature of the Burma type is, however, that de these are “separated by a much less stronger cordelette, a character = which apparently does not occur with the Indian form. D'Archiac's fig. 18. shows a similar feature, although less marked. So far as I am able to say, the specimens from Minbu show this character in aless marked way than those from Yenangyat, but on the whole I do not think |. пем name for the specimens from Burma. that; this would establish a distinguishing feature and justify a (21) 22 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, i SILIQUARIA, Sp. The only specimen which belongs to this genus is too ill-preserved to permit a specific identification; so far as can be ascertained it ` consisted of five irregular whorls which are covered with numerous but somewhat irregular longitudinal striae, which are so close to- getherthat a kind of shaly sculpture is produced; the slit on the upper side is Ш-вееп, Localit y.—Rare at Yenangyat. Remarks.—lf any comparison can be drawn from this өресіне it may be said that it closely resembles Siliguaría granti, Sow., from the Nari group, although this species is apparently different by having more inflated whorls. CALYPTREA RUGOSA, Spec. nov., PLATE V, Fie. 5—52. This pretty little shell is conical, having a nearly circular circum- ference ; the apex is slightly sub-central; the whorls are ventricose and except for some irregular stris of growth, covered with fine, short transverse striz which give the surface a somewhat plicate appearance. | | idis —Rather rare at Minbu and Yenangyat. NATICA OBSCURA, Sow., PLATE V, Fie. 6— 75. 1840. Natica obscura, Sowerby, Transact, Geol, Soc. of London, 2nd ser., vol. V, plate XXVI, fig. 2. The shell is globular, consisting of five whorls, of which the first four form the low, depressed spire; the suture is sharp and well defined; the surface is smooth, except for some occasional strize of growth ; a very shallow depression runs just alongside the suture on the upper end of the whorls, Outer lip sharp ; inner lip. thick and callous, only partly covering the deep umbilicus. Locality.— Common at Minbu and Yenangyat. Remarks.—This species is easily distinguished from Natica callosa by alittle higher spire, and by the shallow depression running alongside the suture on the upper part of the whorls ; the striae peu) : | GASTROPODA. | | 23 of growth are here sometimes, but not always, a little more distinctly and regularly marked so as to form very fine plaits. NATICA CALLOSA, Sow., PLATE V, FIG. 8— 8a. z; 1840. Natica callosa, Sowerby, Transact., Geol, Soc, of London, 2nd Ser., vol, V, ' | plate XXVI, fig. 3. The sub-globular shell consists of five whorls which form a very ` low spire and a large ventricose body whorl; the suture is not very well marked ; the surface perfectly smooth, except some occa- sional striae of growth; aperture obliquely elliptical ; outer lip sharp ; inner lip thick, callous, partly covering a deep umbilicus. Locálity.—Common at Minbu, rare at Yenangyat. Remarks.—This species apparently attains a larger size than Natica obscura, and is easily distinguished from that form by the exceedingly low spire which hardly projects over the last whorl. SIGARETUS (P) BICOSTATUS, Spec. nôu., PLATE V, Fic. 9—9a. Only one specimen has come under examination and this is by no means well preserved; the small shell of obliquely globular shape consists of about four whorls ; the spire is very low, the last whorl large and ventricose; the sculpture is formed by fine revolving ribs which are separated by interstices of the same breadth, some- _ times, particularly in the upper part of the last whorl, a fine filiform rib is intercalated between two stronger ones; aperture large, elliptical; outer lip sharp ; inner lip probably sharp. — . Locality.—Very rare at Yenangyat. | Remarks.-—The generic position of this species is not quite certain, because the features of the aperture are only indistinctly known; the sculpture of the surface however aintingsisher this species readily enouph. CERITHIUM, 8^. Prate V, Ев. 10--104. А fragment of a turreted shell probably represents this genus; the whorls are low, slightly inflated and covered with four or five ( 23 ) , x ww... ТАҒЫ E a 2 БЕ” as, "ET y 24 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. ' very regular revolving ribs, separated by interstices of about the same breadth; they are crossed by thinner, equidistant longitudinal ribs with very regular, low tubercles on the former, Locality.—Very rare at Minbu. Remarks.—To judge from the sculpture the above species must be closely allied to Cerithium pseudocorrugatum, d'Arch., but I refrain from expressing a definite opinion owing to the fragmentary state of the specimen. APORRHAIS, Sp. The fragment of a spire of a turriculated shell, which consists of six whorls, carrying a sharp, slightly granulated keel in the centre might perhaps belong to this genus. The surface of the whorls is slightly concave above the keel and slopes towards the suture, while it is flat and perpendicular below it. Locality.—Rare at Yenangyat. | Remarks.—This specimen agrees so well with d’Archiae’s Cerzf- hium, spec. indet. plate XXVIII, fig. 16, that I am convinced that both represent the, same species; however, nothing definite can be said owing to the incompleteness of the specimen. STROMBUS NODOSUS, Sow., PLATE V, Fie. FI. 1840. Strombus nodosus, Sowerby, Transactions, Geolog. Soc. of London, 2nd series, vol, V, Plate XXVI, fig. 19. ЖЫ. 1852. Strombus nodosus, d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique de Plnde, page 316, plate XXX, = 20 and 21 (Non fig. 18!) | y The specimens found by me are unfortunately rather mutilated, so that their generic identity is not quite certain; they exhibit, however, such features that I think they must be identical with the species quoted above. The shell is pear-shaped, and consists of flat whorls which form a rather elevated spire ; along the edge they are set with a line of nodules which gradually grow into short, blunt’ spines. The whole surface is covered with fine revolving ribs of which stronger and finer ones alternate rather regularly. (2) hod d ә Lr 7 J TO ve mi үт % 2 ] ; ұлығы Аре ғ ғ 1 a) д 222002277 GASTROPODA, 25 ұғ Locality.—Rare at Minbu, Remarks.—It is unfortunate that the type specimen described by Sowerby is so ill-preserved that it is most difficult to arrive at a final decision from the figure only; the general appearance is, e however such, that I do not doubt that the specimens from Burma must be referred to this species. Their identity with those de- scribed by d'Archiac and Haime isless doubtful, although they are considerably smaller than those. Why d'Archiac considered fig. 18, which either belongs to the genus Rostellaria or Aporrhais, as identical with figs. 20 and 21, must remain an open question. At the first glance the difference of the form represented by fig. 18 from figs. '20 and 21 is so striking, that it is difficult to understand why - d'Archiac should have considered them as identical; the difference must have been noticed by the author himself, because in the description he especially mentions that he considers fig. 18 asa variety only. i In conclusion I want to draw the attention to the close resemblance of Strombus nodosus, Sow., in its type from Burma to Strombus coronatus, Def., particularly to those forms as figured by Hoernes! ; the resemblance is so striking that I rather feel inclined to think | the specimens from Burma identical with that form, but I refrained — from doing so on account of their mutilated shape which did not permita decisive opinion. I think, however, thatthis is highly pro- bable but only actual comparison of better preserved specimens will . decide this question ; in the meantime the name of Strombus corona- | физ, Sow., may be retained for the Indian and Burmese varieties, + TIE "15 . PA, ылы wer 2” w h w CYPRAEA GRANTI, 2 Archiac, PLATE V, Fic. 12—120. 1853. Сурга granti d'Archiac and Haime, Descr. des. Anim. foss. du groupe num- mulitique de l'Inde, page 332, tab. XXXII, figs. 14and 14a. The oval shellis ventricose, a little more attenuated anteriorly than posteriorly ; surface perfectly smooth ; aperture narrow, shortly ! Die Gastropoden der erst. und. zweit. medit, Stufe. Abhandl d. К.К, Geolog. Reichsanst., vot. XII, Heft 1, plate XVIII, figs. 2, 3 and 5. | | С a5.) 26 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, channelled at either end; inner lip strongly crenulated; outer lip inflected, thickened and equally strongly crenulated. Locality.—Common at Minbu and Yenangyat. Remarks.—This species attains a considerable size ; specimens from Yenangyat, although crushed, measured certainly not less than 26 mm, in length, but such are rather rare; the most common are those of 17 mm. in length. Messrs. d'Archiac and Haime put special stress on the difference of the denticulation of both lips; this how- ever depends entirely on the state of preservation and on the way in which the light is reflected ; if there is a difference, it is that the denticulation of the outer lip is slightly stronger than that of the inner, but it is so small that it is hardly perceptible. TRIVIA SMITHI, К. Martin, PLATE V, Fie. 13—15c. 1883-87. Cyprea (Trivia) smithi, К. Martin Beitrag. zur Geolog. Ost, Asiens, vol. ІП, page 141, plate VIII, fig. 14. The shell is small, not longer than ro mm., but very ventricose the last whorl being 6 mm. high; the aperture is very narrow with a short canal at either end; the outerlip is inflected ; the surface is covered with sharp fine ribs, which form the continuation of the crenulations of the inner and outer lip resp., whichstarting from the aperture meet onthe opposite side of the last whorl, in such a way that the ribs from both sides alternate, being separated by an indistinct dorsal sulcus ; however, not all the ribs reach up to the middle, but some of them die out before, Very fine transverse stria: may be seen between the ribs. | Locality.—Rare at Yenangyat. Remarks.—The character of the sculpture, as described above, makes it certain that the species from Burma is identical with the form from Java, as none of the other species show such strong ribs alternating on the top of the last whorl, | It is remarkable that Trivia smithi finds its nearest relations | among the species from the West Indian seas rather than among those from the Indian Ocean. Trivia pediculus, Lin., from the West Indian sea is, for instance, closely related to this form, ( 26 ) Мі < E L TR { wy E dl m = E TM De” k: £ С AU M DUROS, = NA шығады. - а AS tdi ou^ за, e A j Е з РЕ NT vr "T ЕТИЦИ a C TA Trans >” FA 2 ( Es -— ае н ы hz m е ` # بز‎ > ETT T . GASTROPODA. | 27 CASSIS D'ARCHIACI, Spec. nov., Puate VI, Fic. 1— 15. 1853. Cassidaria carinata d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique de l'Inde, page 317, plate XXXI, fig. 1. This comparatively small shell consists of six whorls, of which қ the last one is ventricose, and as the spire is very low, the shell has a sub-globular shape, anteriorly a little attenuated, where it termi- nates in a shortly recurved canal. The last whorl carries three revolving rows of low but pointed tubercles, longitudinally arranged in oblique lines ; besides these the sculpture consists of numerous fine revolving furrows which are crossed by irregular striae of growth; the aperture is longitudinal and narrow ; the inner lip spread over a considerable part of the body whorl, and carries three strong plaits towards the anterior end; the outer lip has a thickened reflected margin which is rugosely dentate within and leaves some irregular varices on the former whorls, one of which marks the limit up to which the inner lip extends, Locality.—Minbu : pretty common. Remarks.—Messrs d'Archiac and Haime referred a fragmentary specimen of this species to Cassidaria carinata, Lam. ; thé speci- mens from Burma, which are unquestionably identical with the Indian fragment, prove, however, that they must be distinguished not only because they possess a much lower spire, but because the outer as well as the inner lip is denticulated, while it is smooth in Cassidaria carinata, Lam, CASSIDARIA DUBIA, Spec. nov., PLATE VI, Fic. 2—3. The ornamentation of this species shows such marked differences from any others hitherto described that I feel justified in establishing a mew species. The sub-globular shell consists of at least six ventricose whorls, which are covered with moderately strong re- volving ribs in such a way, that two ribs of equal strength are separat- ed by a fine one, running right in the middle between the two, The revolving ribs are crossed by fine longitudinal stria which, being a little stronger on the ribs than in the interstices, give them a (487 0) ^ 28 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. granular appearance. Irregular varices sometimes present, Outer lip sharp, denticulate, united with the last varix, Locality,—Rare at Yenangyat and Minbu. Remarks,—This form resembles so closely Cassidaria desort, d’Arch, and Haime, that I first hesitated in giving ita new name, but after some consideration I think I am justified in doing so because d’Archiac does not mention the longitudinal striae, which give such a peculiar appearance to the revolving ribs of Cassidaria dubia; it appears, however, that Cassidaria desor? is founded on some imperfect specimens only, and it is therefore quite probable that if some better preserved specimen were found and examined, the identity of these two forms might be proved, in the meantime we have to be satisfied with having our attention drawn to the close relationship of the two species. CASSIDARIA MINBUENSIS, Spec. nov., PLATE VI, Fic. 4—45. The small shell consists of at least five angular whorls, of which four form a moderately elevated spire; a strong keel runs about in the middle of the whorls, and from this the surface slopes slightly to the deep suture; the last whorl is high, rather attenuated in front, terminating in a short sub-ascendant canal. The sculpture consists of thick revolving ribs, leaving only very narrow interstices between them; these are crossed by longitudinal ribs of. equal strength, which become nodular by the crossing of the revolving ribs and die out towards the front of the last whorl. Aperture narrow ; outer lip sharp, dentate ; inner lip broad and plicose. Locality.—Rare at Minbu and Yenangyat, FICULA THEOBALDI, 5022. nov, PLATE Vl, Fie. 5—5a. The pear-shaped shell consists of five whorls, of which four form . the low: depressed spire ; the last whorl is ventricose and terminates in a short canal; except the first two or three whorls which are smooth, the shellis covered with 15 to 18 fine equidistant revolving : ribs; in the middle between two such ribs there runs another which is slightly thinner, and in the two halves of the interstice thus divided, there are three more ribs, of which the median one is a little ( 28 ) M Ум. De JM 12:71. e M E ior de С a £ P AL " M © I x > ¥ Je hi En x e" k — — Haime have compared this species with 7, retículosum, Lam., but to ы. зу а й x. GASTROPODA. | | 29 stronger than the two others, but thinner still than the central one ў we might divide the ribs according to their strength into four orders, and the interstice between two ribs of first order, would be filled out by one of the second, two of the third and four of the fourth order, in the following sequence, Ist, 4th, 3rd, 4th, 2nd, 4th, 3rd, 4th, Ist order. These ribs are crossed by fine, equidistant longitudinal striae which produce a kind of rectangular net work. Aperture not known. Locality,—Yenangyat, rare. Remarks,—This species is closely allied to F. condita, Brong." but in the latter species the revolving ribs are apparently much stronger and the intermediate ribs much less regular than in the species from Burma, - TRITON (SIMPULUM) DAVIDSONI, 4” Archiac, PLATE VI, Fic, 6—6a. T E 1853. Tritonium davidsoni, 4” Атсһіас and Haime, Desc. des Anim. foss. du groupe р | nummulitique de l'Inde, page 312, plate XXX, fig. 5 a, b. 1879-80. Tritonium javanum, K. Martin, Tertiár auf Java, page 6o, plate 14, fig. 12. 1880-81. Tritonium javanum, K. Martin, Beiträge zur Geolog. Ost Asiens and Australiens, vol. I, page 208, plate IX, fig. 9. The oblong shell consists of about six ventricose whorls; spire prominent ; surface covered with strong rounded and equidistant longi- tudinal ribs, of which there are always three between two varices, _ these are crossed by fine revolving ribs, which when crossing the longitudinal ribs or varices, produce thereon a kind of horizontally extended nodule, Aperture ill-seen ; outer lip thick and denticulated. Locality, Соттоп at Minbu. Remarks, —The specimens from Burma are unfortunately very ill- preseved, none of them having a complete shell, but the characteristic sculpture of the whorls is so exceedingly well exhibited that there is not the slightest doubt as to the identity. Messrs. D'Archiac and judge from Deshayes' figure? the resemblance is a very distant one, 1 D'Archiac and Haime; Descript. des Anim., plate XXXI, figs.2 and 2 a, 2 Coquilles fossiles des environs de Paris, pl. LXX XIII, fig. 2 and 3a. ( 29 ) 30 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. There is, however, another form which is closely related to, if not identical with, T. davidsoni, and this is Tritonium samaranganum, K. Martin." The latter form exhibits exactly the same ornament- ation of the surface, particularly the horizontally extended nodules on the longitudinal ribs, and 1 at first felt inclined to consider both species as identical. Martin states, however, that two rows of nodules become prominent above the others, in 7. samar- anganum, a character which cannot be traced in 7. davidson:, where all the nodules are of equal strength; on the other hand it must be mentioned that, although this feature has been mentioned in the de- scription of 7. samaranganum, the figure hardly shows it; in fact to judge from the figure the difference in the strength of the single rows of nodules, hardly exceeds that noticed in Z. davidsoni. It may be possible that the future may prove the identity of the two forms, but for the present we must keep them separate notwith- standing the close relationship. . K.. Martin specially lays stress on this character, when distinguish- ing T. samaranganum from T. javanum, in which latter species thre is no difference in the strength of the nodules. I am of opinion that, considering the sculpture of the shell, 7. javanum must be considered identical with 7. davidsont, if the above-men- tioned distinguishing feature between Z. samaranganum and T. davidsoni really exists in such a marked way. TRITON PARDALIS, Spec. nov., PLATE VI, Fie. 7—84. This pretty little species consists of six moderately ventricose whorls, of which the last one is of about the same height as the spire ; the total height is about 16 mm. ; the sculpture consists of fine flat revolving ribs, which are separated by interstices of about the same breadth as the latter, containing from 1 to 3 filiform revolving lines ; on the spire there are also longitudinal ribs, which grow fainter 1 K. Martin, Beitráge z. Geol, Ost Asiens and Australiens, vol. ШІ, page 132, pl. VII, fig. 133. i: 422 Уды ( 30 ) | | | ¿a d T re. 2272 GASTROPODA. 3£ and fainter, till on the body-whorl they have entirely disappeared ; varices few, moderately strong; the aperture is wide and terminates in a short anterior canal; the outer lip is sharp and merged into a moderately thick varix ; inner lip thin. Locality.—Rare at Minbu, common at Yenangyat. -Remarks.— This species might at first sight be mixed .up with T. davidsoni, but a closer examination will at once show the difference ; in 7. pardalis the last whorl bears no longitudinal ribs, while in 7, davidsoni they are particularly strongly developed, RANELLA TUBERCULARIS, Lam., PLATE VII, Fic. 1—1c. 1853. Ranella vipevina, d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique de l'Inde, page 310, plate XXX, fig. 2. 1879-80. Ranella junghuhni, K. Martin, Die Tertiárschichten auf Java, page 54» plate X, fig. 2. 1881-82. Ranella raninoides, K. Martin, Beitráge zur Geologie Ost-Asiens und | Australiens, vol. [, page 203, plate IX, fig. 6. The shell consists of six moderately ventricose whorls, which gradually increase in height ; spire prominent ; last whorl of about the same height as spire. The ornamentation consists of strong revolving ribs, of which there are generally three visible on the earlier whorls, while there are 9 to ro on the last whorl; between these there are generally one but sometimes two fine filiform lines. The revolv- ing ribs are crossed by longitudinal ribs which on the point of crossing produce strong, rounded nodules on the first; two con- tinuous lines of strong varices are nearly opposite to each other; ` aperture small, terminating in a short anterior canal; outer lip sharp, denticulate, and united with the last, thick varix. Locality.— Not rare at Minbu, common at Yenangyat. Remarks.—The above species was first described by Messrs. d'Archiac and Haime who compared it with Trifonium viperinum, Lam. ; it cannot however be said that there exists a close relation- ship between the two species. | Under the name Ranella junghuhni K. Martin has described a species from Java which must be considered identical with R. viperina; (ga. -) 32 NOETLING: MARINE FOSSILS FROM MIOCENE UPPER BURMA. there is certainly no difference in the sculpture between the specimens from Burma and K. Martin's type from Java. Martin specially mentions that the regular net-like sculpture characterises this form; this is however not so constant a feature, I have some specimens which exhibit that character very well, others in a lesser degree. It is particularly this character which was to dis- tinguish Ж. raninordes from R. junghuhni ; but as certainly R. viper- ina from Burma is identical with Æ. Junghuhni; and as in the first one the regular net-like sculpture is somewhat variable, [ am of the opinion that №. junghuhni and R. raninoides are identical, and must be considered as the same species as A. viperina from Western India. After comparing the fossil forms with the living Ranella tuber- cularis, Lam., lam certain that they are identical with that species because I AU discover the slightest Чшекепее, either in shape or in sculpture. NASSA CAUTLEYI, d’Archiac, Prate VII, Fie. 2—4a. 1853. Buccinum Cautleyi, d'Archiac and Haime, Description des Animaux fossils du groupe nummulitique de l'Inde, page 320, plate d figs. 12, 12a and 13. The shell is fusiform, and attains a length of 19to 20 mm. It con- sists of seven or eight whorls, the first six are flat, low and only gradually increase in height; the last one is slightly ventricose, forms about 2rds of the total length, and ends in a short truncated anterior canal, Aperture rather narrow and ovate; inner lip thin; outer lip callous and denticulated within; the whorls are covered with strong longitudinal ribs, which increase in strength in the centre, and fine regular striae, well marked towards the top and the basis of the last whorl, where the centre appears more or less smooth to the naked eye. Locality.—Very common at Minbu, rare at Yenangyat. | Remarks.—The species from Burma agrees so well with the | one from Hala, that there is little doubt that they are iden- | tical. The chief characters—regular, fairly strong and equidistant, | [:82-) “ - part remains smooth ; anteriorly the lines are much stronger, ` fine revolving ribs are produced; those on the posterior part remain _ always fine, and become easily effaced’; the aperture is small, ellip- GASTROPODA. 33 longitudinal ribs, which are crossed by fine filiform striae, chiefly marked towards the base and the top of the whorls—are well repre- sented in the specimens from Burma. . Nassa cautleyi is apparently closely related to Nassa siguijoren= sis, Ad., from Java. K. Martin describes this species in detail, but to judge from his figures, it must vary very much in appearance. Without having the originals before me, 1 am unable to form an opinion whether these different forms should be united under the same specific name or not. The species from Burma certainly shows no such varieties ; on the contrary, its characters remain most uniform; Fig. 119 of those given by Prof. Martin shows the closest agree- ment with our specimens ; the only difference apparently consists in the shell being a little more ventricose, and the longitudinal ribs more numerous and finer. CLAVELLA DJOCDJOCARTA, K. Martin, sp, Puatz VII, Fic. 5—7a. 1883—87. Pusio djocdjocartz, K. Martin, Beiträge zur Geologie Ost-Asiens und Australiens, vol. III, page 104, plate VI, fig. 105. Although one of the commonest species not a single specimen _ js completely preserved, but from the numerous fragments it is easy to fix the characters. The shell is sub-fusiform, and consists of at least seven whorls, of which the last one is suddenly contracted in front ; the spire is acuminate, and its whorls have a different sculpture from the last one; on the earlier whorls broad but low longitudinal ribs may be seen, which produce a kind of undulating suture; these ribs of which there are six to one whorl, become obsolete the larger the shell grows, and have entirely disappeared on the last whorl; the latter shows only finely engraved revolving lines which are also pre- sent on the spire, arranged in two sets in such a way that the central in fact . tical and has a short posterior m a very long anterior canal ; the D | 33 22 34 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, outer lip is thick, the inner lip sharp, and separated from the colus mella by a fine furrow; a single plait visible just at the place where the last whorl contracts. Locality.—Very common at Minbu, but rarer at ME Remarks.—Clavella djocdjocartz has been described by K. Martin on very insufficient material, inasmuch as he had only three speci- mens for examination ; the figure he gives is also very rudimentary, as it shows only the aperture and the last whorl, but notwithstand- | ing this I am convinced that the specimens from Burma are identical with those from Java. "There can be no mistake about the remark- - able difference of the sculpture of the spire and body-whorl; the single plait on the columella is a further identical feature; the original of К. Martin's fig. 105 was apparently much rolled because it does not show the revolving lines; now none of my specimens from ` Minbu show the revolving lines on the last whorl, they are apparent- ly worn away, and they are only faintly visible on the spire, while those from Yenangyat which were apparently not much rolled | show them very well. K. Martin does not mention the engraved revolving lines, and if I had had only specimens from Minbu, I should not have noticed them at all; I therefore do not attach too much importance to this feature, although it may seem that the specimens from Burma differ in this from the type specimens. | FASCIOLARIA NODULOSA Sow., sp., PLATE VIII, Fre. 1—34. 1840., Fusus nodulosus, Sowerby, A Geol. Soc. of London, 2nd ser., vol, V, plate XXVI, fig. 14. | The specimens are not well preserved, but still they permit deter- mination ; the fusiform shell must have attained a considerable size, | as some of the fragments belong to specimens of not less than 45 mm, | in height ; it consisted of at least seven whorls, of which the last one is strongly contracted in front ; the spire is high, the suture deep, slightly _ undulating; the sculpture consists of thick knob-like short longitudi- nal ribs, acuminate at both ends ; across these run fine revolving lines, a little irregular in strength, which brogue stronger on the frontal ( 34 ) GASTROPODA. | | 35 part of the last whorl. Sometimes a finer rib is inserted between two _ stronger ones; aperture rather small, terminating in a long straight canal ; outer lip unknown, inner lip rather thick ; at least four strong plaits on the columella. Locality.—Yenangyat and Minbu ; pretty common. | Remarks.—Sowerby’s figure of this species is very defective, and might be taken for any other species belonging to this group. I have, however, not the slightest doubt that the specimens from Burma must be referred to Sowerby’s species. Fusus intortus, Lam., parti- cularly Deshayes’ var. a, fig. ro and 11,* resembles this form so closely that I felt almost inclined to consider the species from India and Burma identical with it; the columella is, however, longer and more attenuated in Z. nodulosus than in F. ¿ntortus; there аге no plaits on the columella of the latter, while they are certainly present in Z. nodulosus, which also affords the best distinguishing feature, although it must not be forgotten that it would be difficult, if not impossible, to distinguish fragments of Fasciolaréa nodosa without aperture. | | FASCIOLARIA FEDDENI, Spec. nov., PLATE VIII, Fic. 4—40. Only one specimen of this pretty species has been found, but this shows such a peculiar character that a new name is fully justified ; only part of the spire and last whorl being preserved, nothing can be said about the shape, but apparently it was fusiform ; the ornamenta- - tion consists of big longitudinal nodules, which posteriorly terminate rather abruptly before reaching the suture; they are crossed by strong revolving ribs of which there are four on the spire, and not less than 11 on the last whorl ; these ribs do not, however, extend completely over the whole whorl, but only a single one runs close to the suture ; then follows a broad band covered apparently with fine undulating lines only, and then at about the same height as the nodules, begin the ribs, which extend over the remainder of the whorl; the inter- stices are filled with very fine undulating pues | Locality.—Yenangyat, very rare. 3 Coquilles fossiles des environs de Paris, plate 72, (3) 36 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, MUREX (MURICIDEA) Sp. Although specimens belonging to this genus are pretty common, none of them are sufficiently well preserved to allow a specific de- termination; so far as can be seen, the shell was rather globose, ter- minating in a moderately long canal ; the spire is low, the last whorl ventricose ; ribs and varices of nearly equal strength and crossed by | coarse revolving ribs, in the interstices of which there are usually . three fine revolving lines, of which the middle one is a little stronger than the other two. The aperture is small, the inner lip slightly spread across the columella; outer lip sharp, united with the last varix; on the end of the columella a few shaly spines, which are apparently formed by the termination of the longitudinal ribs. Locality.—Rather common at Minbu and Yenangyat. MUREX TCHIHATCHEFFI, a*Arch., PLATE УІН, Fic. 5. - 1853. Murex Tchihatcheffi, d'Archiac and Haime, Descr. des Anim. foss. du groupe nummulitique de l'Inde, page 311, plate XXIX, fig. 23. The single specimen shows well the subangular inflated whorls, divided by а deep suture; there are nine, strong club.like, slightly | oblique, longitudinal ribs on each whorl; the ribs are thickest near the keel and accuminate towards the base; those of the last whorl ex- tend on the columella, where, however, they form only tile-like laminze, Locality.— Rare at Yenangyat. | | Remarks.—Although very incompletely preserved, it still shows such characters as to leave no doubt about its identity ; the fine revolving lines which d’Archiac mentions are only imperfectly seen in the specimen from Burma which was apparently much rolled. MUREX ARRAKANENSIS, Spec. nov., PLATE VIII, Fic. 6—6b. The pyriform shell consists of a low spire, of about four whorls, and a high ventricose last whorl attenuated in front and terminating in a short closed canal. There are three varices, ending in short spines, which correspond to. moderately strong revolving ribs: _ between the latter numerous fine revolving lines ; aperture oval; outer lip thick, inner lip reflected and sharp. 8 GASTROPODA. par: 37 Zocolity—Rare at Yenangyat and Minbu. ` Remarks.—1 cannot find any other species with which M. arra- Zanensis could be compared but Murex javanus, K. Martin; the latter. is, however, al distinguished by the long canal and the strong spines, | VOLVARIA BIRMANICA, Spec. nov, Prate VIII, Fic. 7—7c. The shell is subcylindrical in shape ; the spire is very short and nearly perfectly concealed; the surface is covered with fine, regular revolving furrows, which are divided by very fine longitudinal striae into very regular small squares ; the ribs between the furrows are of about double the breadth of the former and perfectly smooth, except for some occasional striz of growth, but the fine longitudinal lines never extend on to the ribs, The columella is straight, a little callous on the posterior end ; four moderately thick oblique plaits on the an- terior end ; outer lip thick and slightly crenulated ; aperture narrow. Locality.— Rare at Minbu. Remarks.—The peculiar sculpture and the four plaits on the an- terior end of the columella distinguish this species from all the others ; the nearest species 15 Vofvarza multicingulata, Sand., from the tertiary formation of the Mayence basin;this species is, however, easily distinguished by the smaller number (3) of plaits on the columella, which are apparently thicker and by the longitudinal striz running across the furrows and ribs alike, so that a kind of chequered sculpture is produced. | VOLUTA DENTATA, Sow., PraTE VIII, Fie. 8—10. 1840. Voluta dentata, Sowerby, Transact. Geol. Soc. of оь 2nd ser., vol. V, plate XXVI, fig. 26. 1853. Voluta dentata, d'Archiac and Haime, Desc. des Anim foss. du groupe : nummulitique de l'Inde, page 324, plate XXXII, figs. 2; 2а, plate XXXIII, fig. 11. . 1852. Voluta cythara, d'Archiac and Haime, ibid. page 325, plate XXXII, figs. 4, $: ` The turbinate shell consists of five whorls, of which four form the low turreted spire ; the last whorl is very high, accuminated in front; pretty close to the suture runs a sharp keel above which the surface D2 | 252472) 38 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, slopes and is slightly excavated ; the keel is set with short, pointed tubercules, from which issue strong longitudinal ribs, which disappear -in about half the height of the whorl; it must be noted that these ribs are only wellseen on young specimens, while on larger ones they are very short and indistinct. As each whorl is enveloped by the succeeding one up to the keel, the spire appears slightly spinose. | On young specimens there exist also fine revolving ribs which be- come stronger towards the base ; on full-grown specimens the revolv- ing ribs disappear on the upper part, where they are replaced by irregular lines, and only remain near the base. Aperture high and narrow ; outer lip straight and thick, probably denticulated inside. Inner lip callous ; five strong plaits on the columella. Locality.— Common at Minbu and Yenangyat. Remarks.—The sculpture of this species varies a little during the time of growth, inasmuch as it is more distinctly marked on . younger specimens than on full-grown ones, on which it nearly disap- pears ; the difference is so marked that at first sight one might be led to believe that the younger form represents a different species, but. on laying bare the earlier whorls of a full-grown specimen I could see that the longitudinal and revolving ribs gradually grow more distinct, It is for this reason that I have united Voluta cythara, d' Arch., with Voluta dentata, Sow.; in fact young specimens of thisspecies cannot Бе distinguished from Voluta cythara, d' Arch, I consider the chief distinguishing features of this species the line of tubercles on the keel, from whichissue moderately long longitudi- - nal ribs. OLIVA DJOCDJOCARTA, K. Martin, Prate IX, Fie. 1—10. 1883—87. Oliva djocdjocartz, K. Martin, Beiträge zur Geologie Ost-Asiens und Austra- liens, vol. III, page 77, plate V, fig. 80. The shell is oblong, subcylindrical, and has a low spire, of at least six low, flat whorls, divided by a deep, canal-like suture, other. wise they are perfectly smooth; the last whorl is, except for some strize of growth, smooth; the aperture is narrow and straight; outer lip thick; on the columella five larger plaits, between which small ( 38 ) GASTROPODA. | 39 : ‘Ones are inserted ; the last and highest of the thin plaits, meets the 8 basal plate at a very acute angle. a - Lecality,—Common at Yenangyat and Minbu. Ei ` Remarks,—The arrangement of the plaits on the columella is А. ¡according to К, Martin the chief distinctive feature of this species ; 1 .now the specimens from Burma show the secondary plaits, inserted К, _ further in between the primary ones, as well as the acute angle at | - which the last one meets the basal plate. CANCELLARIA CANCELLATA, Lam., PLATE IX, Fic. 2-22. ‚ (Synonymes : Hoernes, Die fossil. Mollusk, des Tertiár v. Wien. Abhandl, d. K. K. Geolog. Reichsanstalt, vol. III, page 316.) | ` Only one specimen of 14 mm. height has come under examina- Р tion, but this is so well preserved that there can be no doubt as to its identity. The shell is sub-globular, the whorls ventricose, the suture deep. The sculpture consists of strong longitudinal ribs which run obliquely and are a little accuminated at both ends; they are crossed by strong revolving ribs, which alternate rather regularly with finer ones ; in the interstices minute longitudinal lines produce | . areticulate sculpture ; aperture not clearly visible. Locality.— Very rare at Yenangyat. Kemar&ks.—]t is greatly to be regretted that only one specimen of this interesting form has been found, which so far seems to differ in no way from living specimens in the collection of the Indian Museum at Calcutta. ! RAPANA, Sp. | A very. ill-preserved shell, possessing an elevated türreted spire | and strong nodules along the keel of the whorls; it might perhaps be- long to this genus, considering that there are signs of rather a large umbilicus; on the last whorl there are a few irregular р зна ribs. Й 4 Locality.—Rare at Yenangyat. P TEREBRA FUSCATA, Brocc., PLATE ІХ, Fic. 3—4. ? | 1856. Terebra fuscata, Hoernes, die foss, Moll. des Tert, Beck. v. Wien, Abhandl, m ie. "алса Сесіор, Reichsanst., vol. III, page 128, plate 11, L - figs. 15, I6, 17, 18, 26. | None.of {һе specimens under examination are completely рге- 3 ( 39 ) E" E. 40 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. served; except one fragment belonging to the lower part of the shell, the rest consists only of parts of the earlier whorls; these are high, flat, and divided by a false suture which runs in about 2rds of the height from the base ; the surface is covered with sharp longitudinal ribs, bent in an S-shaped curve and generally more or less interrupt- ed by the false suture. On the later whorls this ornamentation disap- ` pears, and the ribs are represented by fine, closely set S-shaped lines. ` Locality. —Pretty common at Minbu ; rare at Yenangyat. Remarks.—Although found only in fragments, I have not the slightest doubt that they represent this well-known species from the Miocene and Pliocene; the specimens from Burma agree even in the slightest details with Terebra fuscata, A living relative is Terebra anomala, Gray., from the Madras coast, although the latter represents a distinct species. | PLEUROTOMA VOYSESI, d’Archiac, PLATE ІХ, Fic. 5—sa. 1853. Pleurotoma Voysesi, d'Archiac and Haime, Desc. des Anim. foss. du groupe і nummulitique де P Inde, page 305, pl, ХХІХ, бр. ro. The specimens I collected at Minbu show, although they are in rather a fragmentary state, none of them being complete, the dis- tinctive features of the above species so well that I do not hesitate for a moment to identify them with this species. The whorls are strongly careened in the middle and separated by an indistinctly marked suture, each whorl involving the preceding one, nearly up tothe keel. Above the keel the whorls are deeply concave, below it slightly convex. Below the suture runs a slightly less marked ridge. which is indistinctly granulated. The keel itself is plicated by very regular short ribs which extend over the lower half of the whorl in the shape of fine longitudinal striz, which frequently bifurcate. Very fine revolving strize cover the whorls, and are particularly well expressed | on the lower half of the body-whorl, where they become a little granular — owing to the crossing with the longitudinal stria, Locality,— Minbu, ( 40 ) a Ê PLEUROTOMA (CRYPTOCONUS) IRRAVADICUS, Spec. 200, PramrE IX, Fic. 6--ба. - Unfortunately none of the three specimens under examination are completely preserved, but, although fragmentary, they are suffi- cient to show the distinctive features; the shell is mitriform, consist- ing of flat, rather high whorls, with a sharp suture; the ornamenta- tion is rather remarkable; it consists chiefly of revolving ribs, which show a peculiar arrangement; two of moderate strength run quite close to the suture ; below these follow five very fine lines quite close together, which mark the position of the slit; below these follow three ribs of the same strength as those near the suture, between which there are two more delicate ones; then follow at least ro equidistant strorger ribs. On the spire, and much less distinctly, on the body-whorl, they are crossed by fine longitudinal ribs, which thus produce a kind of indistinct reticulation and obsolete nodules on the crossing points. Aperture unknown. Locality—Rare at Minbu. a Remarks.—To judge from the ornamentation only, this species seems to belong to the sub-genus Cryptoconus, a supposition with _ which the position of the slit close to the suture would fully agree ; more and better preserved specimens are, however, required to decide this question. | PLEUROTOMA (DRILLIA) INTERRUPTA, Гат, PLATE X, Ета. 1—2. 1883—87. Pleurotoma (Drillia) interrupta, K Martin, Beitráge zur Geologie Ost- i Asiens und Australiers, 154 ser., vol. III, е м page 65, tab. X., figs. 66, 67, 68. . Only a few ill-preserved specimens have come under examination, but they exhibit the features well enough to allow of identification. The shell is small and fusiform ; the sculpture consists of longitudi- ‘nal nodules, which are crossed by fine revolving ribs, one of which runs quite close to the suture above the slit, finer lines are occa- sionally seen in the rather broad interstices. Locality,—Rare at Yenangyat and Minbu. | (4) 42 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA, -Remarks.—The specimens from Burma agree in general shape very well with K.Martin's figs. 66 and 67; but it seems, that the nodular ribs are much stronger and broader in the Burma variety; when rolled, the revolving lines easily wear away ; only the one just above “the slit is always preserved, which gives the shell rather a peculiar appearance at first sight, but which makes it easily recognisable. PLEUROTOMA VENANENSIS, Spec. nov., PLATE X, Fie. 3—3а. All the specimens under examination being more or less muti- lated, it is difficult to judge of the shape of the shell, but it was ap- parently turreted, the whorls low, only gradually increasing in height and slightly rounded; suture deep; the sculpture consists of four strong revolving ribs on the spire, and at least seyen on the last whorl; one runs along the suture, and the next one below, which eg the position of theslit, carries very regular low tubercules; finer lines are seen in the interstice and these are crossed by oblique longitudinal lines producing a very fine net-like ornamentation parti- cularly well visible on the lower part of the last whorl. Locality. Pretty common at Minbu and Yenangyat. CONUS (RHIZOCONUS) MALLACANUS, Zwass, PLATE X, Fic. 4—7a. 1879-80. Conus javanus, K. Martin, die Tertiár Schichten auf Java, page 12, P II, fig. 3. The conical shell has a slightly raised spire; on the upper side the whorls,show from four to five, very fine revolving lines, and on the earlier whorlsthe keel was lined with indistinct tubercules, from which issued short and faint ribs ; they disappear, however, very soon, and except for some stria of growth, the keel and surface of the last whorl are perfectly smooth ; on the anterior end of the latter a number of fine revolving lines can be seen ; aperture narrow ; outer lip sharp and straight. | Locality.—=Very common at Minbu; rare at Yenangyat. Remarks.—K. Martin founded this species on a single specimen from Java, and it may be doubted whether a single specimen of Conus € 42 ) | CRUSTACEA. Б. | 43 ET сеш to establish а new species, and still more whether it is advisable to refer specimens from rather a distant country to that species ; in general shape and particularly as regards the fine lines ` on the upper part of the whorls (rather ill-seen in K. Martin's figure), the specimens from Burma agree, however, so well with that from Java that I have no longer any doubt as to their identity, I may mention that as a matter of course, the specimens from Burma show also the semi-lunar strie marking the growth of the margin. On comparing this species with the living Rhizoconus mallacanus, Hwass, from the Seychelles, 1 found that they are identical and that the doubt expressed as to Conus javanus was well founded. CONUS (LEPTOCONUS) MARGINATUS, Sowerby, PLaTE X, Fic. 8—85. 1840, Conus marginatus, Sowerby, Transact. Geol, Soc. London, 2nd ser., vol. V, plate XXVI, fig. 36. | The ical shell has a pretty high spire ici consists of at . least six whorls; a fine but deep furrow, above which the surface slightly projects, runs along the suture on the anterior part of the whorls, thus giving the spire a kind of shouldered appearance ; last - whorl high and, except for eight revolving fine furrows on its anterior - end, perfectly smooth ; aperture narrow; outer lip us d Locality.—Not rare at Yenangyat. Remarks.—Thejpeculiar appearance of the pretty high spire dis- _£inguishes this species at once. This species is very closely related to Leptoconus insculptus, Klein, from the Andamans, but the latter is easily distinguished by the sculpture of the last whorl, which is wholly covered with fine revolving ribs. IV—CRUSTACEA. BALANUS SUBLZEVIS, Sow. 1840. Balanus sublaevis, Sowerby, Transact, Geol. Soc. of London, 2nd series, | vol. V, plate XXV, fig. 3. . 1853 , » @Archaic and Haime, Descr, des Anim. foss. du groupe nummulitique de l'Inde, page 341, plate XXIV, fig. 15, a. A cast of a thee of comparatively large size belongs probably (4) 44 NOETLING: MARINE FOSSILS FROM MIOCENE, UPPER BURMA. to this species so far as can be judged from the figures ; it does not however, call for any special remarks. Locality.—-Rare at Minbu, CALLIANASSA, Sp. Some fragments of the hands of rather a large species belonging to this genus are too ill-preserved to allow of specific determination. Locality.—Minbu and Yenangyat; at the latter place rather numerous, PAGURUS, Sp. Fragments of isolated fingers of a pretty large crustacean might perhaps be referred to this genus owing to their thorny ornamenta- ` tion. Nothing definite, however, can be said unless more ' complete specimens are found. Localtty.—Y enangyat. " V—PISCES. LAMNA, Sp. Teeth of this genus are pretty numerous, but I do not think them sufficient to establish the specific identity. As all are, however, of smallor medium size, it may be concluded that they belonged to a rather small species. Locality.—Minbu and Yenangyat. MYLIOBATES, Sp. A fragment of 15 mm. of a spine may be referred to this genus. It shows rather a peculiar section, by which it seems to differ from other known species; but I do not think it advisable to give it a new name. The upper side is nearly semi-circular, smooth ; the lower side flat, but raised in the central part ; edges serrated. Locali¢ty—Minbu. (44) nt a 2.5 Loy PISCES. 45 | GALEOCERDO, Sp. A fragment of a tooth just proves the existence of this genus, Localit y.— Yenangyat. CARCHARIAS (PRIONODON), Sp. Although fragments and sometimes almost complete teeth are pretty numerous, I refrain from identifying them specifically. I do not think myself justified in doing so, considering the great variety in the shape of the teeth according to position, even within the individual, Locality.—Yenangyat and Minbu. | ( 45 ) EXPLANATION OF PLATES. PLATE I. Fig. 1. Paracyathus ceruleus, Dun, nat. size. A 10. n B » enlarged x 2. p 10. » A » nat, size. p IC, » е » enlarged x 2. э 2. وو وو‎ ,, recent. ” 24. 3” 9 35 | » » 3. Eupsammia regalis, Alcock, nat. size. | » 3% وو ` دو‎ ” enlarged x 2. » 4 Daphoderma celata, Reeve, nat. size. » 44. » » yy enlarged x 2. » 5. Nucula alcockz, spec. nov, nat. size. | 2750. » 5 » » Ornamentation, enlarged, » 55. ” وو 99 وو‎ dorsal view. » 56 5 » » » escutcheon, enlarged. x 6. » » » » hinge. j » 6a. » » » » hinge, enlarged. » 7 » » » » lunula, enlarged. » 9. Astarte (?) dubia, spec. nov. nat. size. E ES gs p 34 p ventral view. PLATE II, Fig. 1. Batissa crawfurdi, spec. nov. largest specimen, right valve. » 14. » АА » » й » anterior side. » 10, » » » » » Еж dorsal view. 2. whe » » medium size, right valve. „ 29. » » ipt as » y anterior side, » 2b. » » » » “ » dorsal view. » 3 » » й » hinge, left valve. » 4 m ON OD » » » right valve, » 5. Batissa petrolei, spec. nov. right valve. » 5% » E T „ anterior side, » 50. وو‎ = » » dorsal view. PLATE III. Fig. t. Batissa crawfurdi, spec. nov. small size, right valve. » 14. " » » » = » anterior side. 9: 12, ,” - ” n » » » dorsal side EXPLANATION OF PLATES—continued. Fig. 2. Batissa detrolei, spec. nov, hinge, left valve. 3° ” وو وو‎ » 95 4. Venus cf. scalaris, Bronn, nat. size. 5. Tellina (Tellinella) hilli, spec. nov. nat. size. 5а. "n » » » » enlarged. 6. 3 > n 5 » left valve posterior side, nat, size, 6a. » » » » э apta 2) » enlarged. 7. Tellina kingi, spec. nov. left valve, posterior side, nat. size. 7a. у ” ” ” وو‎ T » » enlarged. 8. Corbula harpa, d' Arch. right valve, nat. size. 8a. » » » » ” enlarged. 8b. 5% 5 " left valve, nat. size. 8. y ” ” » ы enlarged, PLaTE IV. Fig. 1. Trochus buddha, spec. nov. side view, nat. size. Ia. » » 5 « dorsal view, nat. size. 10. » » » » ” » enlarged. 2, % > E » base, nat. size. 20. » T » 2 » enlarged. 3. Trochus blanfordi, spec. nov. nat. size. 34. y » » » Ornamentation, enlarged, 4 i» B n » nat. size. 4a. a 5 5 » ornamentation, enlarged. | 5. Solarium affine, Sow., nat. size. Sa. AR o » dorsal view, nat. size. 5b. » ” ›? „ » enlarged. 6. » » base, nat. size. 6a. » » F » enlarged. s 7. Solarium cyclostomum, Menke, base, nat, size. dorsal view, nat. size. 70 » » » 75. » » » ornamentation, enlarged. 8. Discohelix minuta, spec. nov. nat. size. 8а. А, $5 - » enlarged. 8b. » » Р » Side view, enlarged. 9. Scalaria birmanica, spec. nov. nat. size, 9а. T » j » Ornamentation, enlarged, PLATE V. Fig. 1. Scalaria irregularis, spec. nov. nat. size. 2 m ” » ور‎ » n 24. $ УУ as » ornamentation, enlarged, 3, Scalaria subtenuilamella, d' Arch. nat. size. . 202,7 ux ba » X enlarged, 4. Turritella afinis, d'Arch. nat. size. 4a. н dne У ornamentation, enlarged. EXPLANATION OF PLATES—continued. Hi Fig.5. Calyptrea rugosa, spec. nov. dorsal view, nat. size, » 54. n m s» `» Side view » » т; SEN у; is s зз ornamentation, enlarged. » 6. Natica obscura, Sow., nat. size. n 7: » ” ” 3) 3) B T 4051775 » э» » dorsal view. » 7b. . ” » enlarged. y 8. Natica callosa, Sow., dorsal view, nat. size. n ба. ,, ” » nat. size. . » 9. Sigaretus bicostatus, spec. nov. nat. size. » 9% " i » » Ornamentation, enlarge d, » 10. Cerithium sp. nat. size. » 104. $ » Ornamentation, enlarged. » II, Strombus nodosus, Sow., nat. size. м 12. Cypraea granti, d'Arch. nat. size. 12а. ` » » ” » 5 base, À‏ رر p 120, » 9) Т ” ». side view,‏ Trivia smithi, K, Martin, nat. size.‏ .13 » Ij $ P a » base; nat. size,‏ » 13b. и DIU S » side view.‏ » уз PEN enlarged,‏ » » .130 » PLATE VI.‏ | Fig.1. Cassis d'archiaci, spec, nov. nat. size. » 1а. ” » » n» » » 16. n ” » » » ” » 2. Cassidaria dubia, spec. nov. nat. size. $^ Zas P Я г » ornamentation, enlarged. » 3 n- ” » » nat.size. 254% » minbuensis, spec, nov. nat. size. » 4% » eat i » » » m» 46. 2 5 » Ornamentation, enlarged, pS Ficula theobaldi, spec. nov. nat. size. » 5% » D b » ornamentation, enlarged. » б. Triton davidsoni, d'Archiac. nat. size. s ба. " Ў M ornamentation, enlarged, » 7 Triton pardalis, spec. nov, nat. size. Werden s: » p ornamentation, enlarged, ә 8 No, S T » nat. size, » 8а. » » „ rt ET RET | PLATE VII. Fig. 1. Ranella tubercularis, Lam., nat. size, p 10 2 * » enlarged. » V. رو‎ | a » nat. size, p 1% % » ” enlarged. EXPLANATION OF PLATES—continued. Nash cani lapi d'Agcitiac, part of spire and last whorl, nat. size. » э » » T » enlarged, » aperture, nat. size. » » » enlarged. last whorl and part of spire, nat. size. 2» » ET » . وو‎ enlarged. 5. Clavell a djocdjocarte, K. Martin sp. aperture, nat, size. - €: » Spire and part of last whorl, nat. size, ' % » „ 15 TI » n PLATE VIII. Fig. I. Fasciolaria nodulosa, Sow, sp., part of spire and last whorl, nat. size. 5) » „ IO, о» ” وو‎ 2. ” э Д ..м aperture, nat. size. 3. 4 a 5» » part of spire and last whorl, nat. size. 3a. ES зі в >, Ornamentation, enlarged. 4. Fasciolaria feddeni, spec. nov, nat. size. E 44. » » » ornamenation, ермей. 5. Murex ichihatehefi, d’Archiac, nat. size. 6. Murex arrakanensis, spec. nov. nat. size. ба, hor si E » aperture, nat. size. 00: 0 - B » nat. size, à / Arana birmanica, spec. nov, aperture, nat, size, 7a. T » Mat. size. свету » э, ornamentation, enlarged. 76. ` ww. ә lower pues of aperture, enlarged. 8. Voluta dentata, Sow., nat. size. 8a. = » » Aperture. 9. 3 n и 5 PLATE IX. Fig. 1. Oliva djocdjocarte, K. Martin. nat, size. та. E A E aperture. ж 10. : , ; lower part of aperture, | | enlarged. | 1. А E ЖА CAP as с of last vios enlarged. 2. Cantata cancellata, Гат, nat. size, » 4 » » y » » 20. » " » ornamentation, enlarged. 3. Terebra fuscata, Brocchi, nat. size. | 5 пао У = > Ornamentation, enlarged. 4- is » ` largest specimen, nat, size. Bs Pleurotoma voysesi, d'Archiac, nat, size. | | е р Sa. ss و‎ а “ornamentation, enlarged. - 6. Pleurotoma (Cryptoconus) irravadicus, spec, nov. nat. size. — » ба. vM gs : tee Ұма ornamentation, enlarged, | Ia. 2. 3. 3a. EXPLANATION OF PLATES—toncluded, PLATE X. Fig. 1. Pleurotoma (Drillia) interrupta, Lam, nat. size. m 2 ^ „ Oornamentation, enlarged. » » » » nat. size. Pleurotoma yenanensis, spec. nov. nat. size. » » ornamentation, enlarged. Conus (Rhizoconus) mallacanus, Hwass,, nat, size. > » » 7ч 5. б. ба. 7. 7a. 8. ээ‏ ” ”3 39 ” وو » » و‎ » upper side; nat. size, ээ » » » » » enlarged. » » » ээ nat. size, ээ › 3 >» enlarged. b Conus (Leptoconus) marginatus, Sowerby, nat. size. 3 3) з HJ „ээ n » » > > » spire, enlarged. GEOLOGICAL SURVEY OF INDIA. Мета ХЫ X XVII PtI.P1.1. ж 8 — AE | AA | E Printed al the Geol. Surv. Office. GEOLOGICAL SURVEY OF INDIA. Mem Vol X XVI.Pt.1.P12. GEOLOGICAL SURVEY OF INDIA. Mem. Vol. XXVII. PLI. PL3. Printed at the Geol. Surv. Office. GEOLOGICAL SURVEY OF INDIA. Mem.Vol.XXVII.Pt.I.P14. wawawa ne nun Printed at the Geol. Surv. Office. GEOLOGICAL SURVEY D* F. Noetling. - Kali Dhon Chundra Del 8 Lith. OF INDIA. Mem. Vol. XXVII. Pt.I. PL5. Printed at the Geol. Surv. Office. _ —— — x — q - Y v». bs — = ы a Sa Ya x v P ms. SCC EU bom жән T usa. xG eee 6. Mem. Vol. XXVI.Pt.l.Pl INDIA. Printed at the Geol. Surv. Office. OF SURVEY GE OLOGICAL Seal: Dbon Chundra Del. & Lith. ПЕК Noetimg. ч 247 meni A o udi. E - y Mem:Vol:XXVII. Pt.1.P1.7. Printed at the Geol. Surv. Office. GEOLOGICAL SURVEY OF INDIA. li Dhon Chumdra Del а Lith. ah DEF Nostling. GEOLOGICAL SURVEY OF INDIA. Mem: Vol: XXVII Pt.LPI8. p* Е Noetling. Printed at the бері. Surv. Office. GEOLOGICAL SURVEY OF INDIA. DE E Noetling. Mem. Vol. XXVII. Pt.1. P..9. Printed al the Geol. Surv. Office. GEOLOGICAL SURVEY OF INDIA. DEF. Noetling. Mem. Vol XXVII Pt.I.Pl.10. 2272 xt HER TEk * EISE TTE cj z БА Dhon Chundre Delt Lith... Printed at. the Geol. Surv. Office. w | | қ MEMOIRS 2 ү, 4 ' ; OF E Ш ч рг, } THE GEOLOGIGAL SURVEY OF INDIA, - E e i 4 y ” ; . * ` " y А Li . ` A i LI » 4 5 4 - ` - А t . ы 4“. Pe” % Жұ 7 LENS ҚАҒЫ. | ж. &- 7 y > u `. k Lr Inm \ 2 "Da E ( E cw ; AN қ TORUM" 29. MEMOIRS OF THE GEOLOGICAL SURVEY OF INDIA. VOLUME XXVII, PART 2. — — [NN . -..F ... Published by order oí His Excellency the Governor тее оЁ India in Council. A A A ==, CALCUTTA: SOLD AT THE OFFICE OF THE GEOLOGICAL SURVEY. LONDON: KEGAN PAUL, TRENCH, TRÜBNER, & Co. MDCCCXCVII, GOVERNMENT or INDIA CENTRAL PRINTING OFFICE, CALCUTTA: 8, HAST INGS STREET, © г e о e © 3 zm t с. > „© y . -2 Nn © d [>] E 5 5: © a S E E ме4 = B > d PS x : тш : o > ; | | 3 Ë = 76 B. NES en رند ا ees‏ Š GEOLOGICAL SURVEY OF INDIA. Memoirs. Vol: X AVIL Pt.2. Frontispiece. DE Noethng - Kali Dhan Chandra Lith YENANGYAUNG OIL-FIELD, TWINGON AREA, LOOKING NORTH. bei 7 nc. gr М a" a.” a ts ik. GF, BV V ` ' TABLE OF CONTENTS. — لاه‎ —— PART L—HISTORICAL AND GEOLOGICAL . . . 1—159 CHAPTER 1.—HISTORICAL SUMMARY UP TO 1886. . I— 28 A. Legendary Times |. e А А e I— 4 В. Historical Times . , : ° А . 4— 28 CHAPTER IL—THE OCCURRENCE OF PETROLEUM IN THE DISTRICTS OF PROME AND THAYETMYO 29—3: : k | I. Geographical Position . е . А А 29 2. Geological Features : ° А . . 29 қ 3. Stratigraphical Features; . . . . -, ах 4. Economic Value . e z ° . - 31 CHAPTER IIIL.— THE OCCURRENCE OF PETROLEUM | NEAR MINBU . ° a e . ` 32—49 A ق ی‎ iin EL. 2 I. Geographical Position . . А ° ° 32 2. Geological Features А ° ., 32—33 A. The Pliocene or kvadar Series ; ° 32 B. The Miocene or Pegu Seties . . 33 3. Stratigraphical Features . А ° : > 34 4. The Mud Volcanoes 3 . . 7. :35—49 I. Situation of the Mud ER . ° ° 35 2. Detailed description . Д . . . 36 A. Southern group А ° ° . 36 B. Middle group +. .. ° . А 42 С. Northern group ° . o- "e 42 3. General Features A s ‘ ° 43 1 -CHAPTER IV.—THE PETROLEUM FIELD OF YENAN- GYOUNG E . © Ф . “ 9--123 I. Geographical Position, Area апа Physical Geo- graphy . . - e . ” . 40--52 } А. Beme tract . ; ; . ; ; 5° +8 B. Kodoung tract . ° ° ; ° 5I s C. Twingon tract , , А . А 5I i D. Physical Geography . . ° ; 52 2. Geological Features А а ite ; . 54—63 A. Diluvium . А e ° А 54 B. The Tertiary System . ° ° . 56—63 “1, The Pliocene or Irrawaddi Series « 56 2. The Miocene or Pegu Series . . 60 (aa) The Upper Miocene or Yenangyoung Stage В . a . . . 60 H CONTENTS. (bb) The Lower Miocene or Prome Stage . 61 (a) Lithological characters . ; 61 (b) Palzontological characters - 62 (c) The occurrence of petroleum . 63 3. Stratigraphy . - - E ° А . 77—123 A. General Features . ғ 5 77 (a) Unequality of nen - «s 77 (b) Veins of eruptive mud . . : 80 (c) The anticlinal and dome-like structure 86 (aa) The anticlinal arch ° . 86 . (bb) The longitudinal arch . - 87 В. Superficial sections : А М : 89 C. The sections of the drilled wells 1 Р 9I D. The original sedimentation of the rei ferous beds А = К III E. General conclusions, and further ges of the Yenangyoung Oil-field . . 115 (а) Тһе native reserves ” ” . 116 (b) The area exploited by drilled wells . 123 CHAPTER V. —THE OCCURRENCE OF PETROLEUM NEAR/YENANGVAT . ° ; 4124--137 I. Geographical Position, Area іа Physical Geography А - . . Р А 124 2. Geological Features - ° . 126 A. The Pliocene or MUR. ids . А 126 В. The Miocene ог Pegu Series . . . 126 (аа) The Upper Miocene or Yenan- gyoung Stage . 126 (bb) The Lower Miocene or 6 білге 128 (cc) Тһе Occurrence of Petroleum e 129 3 Stratigraphical Features . - e e 132—137 A. The Superficial sections . . ° I32 B. The sections of the drilled walls > . 133 CHAPTER VIL.—THE OCCURRENCE ОЕ PETROLEUM AT OTHER LOCALITIES ІМ UPPER BURMA . 137 CHAPTER VII—RELATION BETWEEN THE OCCUR- RENCE OF PETROLEUM AND THE MAIN STRUCTURAL LINES OF UPPER BURMA . А ° ч 2 . қ 138—142 CHAPTER VIIL.—CHEMICAL COMPOSITION AND PHY- SICAL PROPERTIES , e edd 143—159 PART IL—ECONOMIC IMPORTANCE OF THE OIL- FIELDS ОРБАН с L—THE YENANGYOUNG OIL-FIELD. . .160—202 1. The Community of Twinzayos and their history 160 2. The Construction of the Pit wells. ° . 164 CONTENTS. 3. The number of wells in the native reserve, - A. Period previous to 1888 . e ° ° B. From 1888 to the beginning of 1895 . ° (aa) Productive wells . ° ° e (1) Depth of pit wells . ° (2) Production of the pit wells . (bb) Unproductive wells . . ec (1) Abandoned wells ° ° (2) Wells under construction + (3) Well sites ° ° . N 4. The Production of the pit wells - A. Period previous to 1886 . ° - ° B. From 1886 to the end of 1894 . А e 5. The drilled wells. . . e A. Number and depth of drilled ae А ° B. Production of the drilled wells . : . 6. Summary of the Production of the Yenangyoung Oilfield . . А . . ° . Hi 172 172 179 180 181 185 191 191 192 192 194 194 197 199 201 202 205 CHaPTER IL—THE YENANGYAT OIL-FIELD . . 205—200 r. The Pit wells ° А 5 : < 205 А. Period previous to 1887 - ° ° . 205 B. From 1886 to the end of 1894 + 5 ; 206 2. The drilled wells . ° ° ° - E 209 CHAPTER IIL—THE PETROLEUM PRODUCTION ОЕ: BURMA қ 210—213 CHAPTER IV.—THE COST PRICE AND THE TRADE ra OF THE BURMESE PETROLEUM 213—226 > > P Diagrammatic section through the Minbu Mud Volcanoes . Local consumption of Crude ОП „ ; . 2. Import of Crude Oil from BR: into Lower Burma š А . 3. Export of Рахова and its Products Pom Rangoon . ° А ° ° . e Appendices. i LIST OF ILLUSTRATIONS (WOOD-CUTS). Diagram showing the mean monthly yield of етт from 1886 to 1894 +. " А Diagrammatic section eie the йй liga кайэ arena- ceous to argillaceous beds, between wells 159 and 161 . Diagrammatic section showing double vie ise above the first oil sand in the Aungbanyo . . . Diagrammatic section showing the intersection of perpendicular, horizontal and diagonal veins of eruptive mud in miocene - sandstone Taungle-yo east of Beme village . . . Diagrammatic section showing diagonal veins of eruptive TE in miocene sandstone near well 310 . ” ° ° . 218 219 221 iv | CONTENTS, Fig. 7. Diagrammatic section showing unconformity aná horizontal veins of eruptive mud in upper miocene sandstone near wells Nos. 530 and 541 . А А 84 » 9. Diagram showing arrangement of the intersecting folds $ in the : Kodoung petroliferous tract. » 9. Oil well diggers, Yenangyoung Oil-field . MEL. + 7060 LIST OF PLATES. Frontispiece : Yenangyoung Oil-field, Twingon Area, Looking North. Plate I. Southern Group of Mud Уер Minbu, іп 1889, Looking North. eS II. Do. do. Mud Volcano | No. 5, Look« ing East. à III. Do. do. in 1895, Mud Volcano No. 5, Looking East. Ж s d Do. do. in 1889, Looking North. ds V. Mud Stream on No. 5 Mud Volcano. "à VI. Do. do. 5 ЖЕМЕ Do. do. » VIII. Veins of intrusive mud in the Beme ravine. IX. Yenangyoung Oil-field. View of the eastern slope of the Ayat- poyo. X. Yenangyat Oil-field. View of the eastern slope of the Taungsin Range near Yenangyat. XI. Map of the ` Distribution of the drilled wells at NEU Yenan- gyoung Oil-field. | XII, Sections through the Kodoung tract. "NP Ж Do. do. » XIV. Sections through the Yenangyoung Oil-field. T. Vo Do. do. XVI. Sections through the Yenangyat Oil-field, Section near Minbu. Section of Mud volcanoes. „ XVII: Section of the Bore holes in the Yanaungchoung Ravine, Yenan» gyat Oil-field. - 4 TP» 71 MEMOIRS OF THE GEOLOGICAL SURVEY OF INDIA, The occurrence of Petroleum ¿1 Burma, and its technical exploita- tion, ûy Dr. Fritz Noetling, F. G. S., Paleontologist, Geolog:- cal Survey of India. | Part L—HISTORICAL AND GEOLOGICAL: CHAPTER I.—HISTORICAL SUMMARY UP TO 1886, مو‎ A —Legendary Times. I we are to believe the native tradition, the origin of the Yen- angyaung oil-fields dates back to those far remote times when won- . ders happened in which our sceptical age refuses to believe. The following is a legend about the origin of the Yenangyoung oil-fields . told me by the Bemë Y waók :— * When King Alaungsitha was 10 years old, he contemplated a visit to Mount Meru, the centre of the Universe, and ordered the building of a magnificent raft, _ which took five years to be finished. In due course the king started on his journey. On arriving near a hill called Minlin (Minlindaung is about a mile south of the Bemà oil-fields) the ship was halted and seven of the Queens asked to be permitted to amuse themselves on the shore. Permission was granted on condition that they should not be away for a long time. When they got ashore, they found a quantity of fragrant liquid oozing out from the rock, with which they besmeared themselves, and the enjoyment they indulged in was of such an engrossing nature that they became oblivious of the injunction notto tarry. For this disobedience the Queens were punished with death. Before they died, they implored that the liquid which was the indirect cause of their death might be made to change its nature. The fragrant liquid was consequently turned into earth-oil.” B CER) 2 NOETLING: PETROLEUM IN BURMA. Through the kindness of Mr. Gibson, Extra Assistant Commis+ sioner, I received a somewhat different account of the legend. The account gives the abridged contents of a favourite “ poway ”1 fre- quently played at Yenangyoung. It runs as follows :— | “ During the reign of Poph Saw Rahan, the eleventh’ king of Pagan, in the year 2 B. E, (A. D. 640), the Myothuggi? of Kyaukka Myo? and his relatives dug a large tank about two miles east of their town for the benefit of the inhabitants. This tank was called Myitta-kan, 7.e., “constructed to gain merit.” Before its completion an earthquake occurred, and on the ground cracking about the tank it filled. with highly perfumed waters (Yenanthasi), which attracted thousands of pilgrims and proved a source of great benefit to the Myothuggi and his family. It was subsequently prophesied by a Rahan (= Póngyi),* named Pón- nawadda Mabi, that at the command of a king the perfumed waters of Yenanthasi would loose their sweet scent and change into an oily liquid emitting a noxious odour, and henceforward be known by the name of Yenan; but these effects, far from causing any dis- tress to the descendants of the Myothuggi, who would be 24 in number, would on the contrary benefit them greatly, as the Yenan would be of great demand for preserving of * pezois" (=palm leaf with sacred writings) and for illuminating pagodas and temples. Years passed, and the time for the fulfilment of the prophecy was at hand. The King Alaungsitha Mingyi of Pagan having heard that Kyaukka Myo was a famous town and contained many wonders, made up his mind to pay the place a visit. Accordingly he left Pagan on the 4th day of the waxing moon of the month of Pyatho 460, Burmese Era (— January 1099 A.D.), with the following retinue :— 28 ladies under charge of a eunuch аша Куе Pónna, 100 bos (=officers and wise men), 80,000 troops, rank and file, I2 towing boats and rafts, з Poway, is the national Burmese drama. 3 Rockcave town, now Yenangyoung. a Headman, * Burmese priest or monk. SE 49. ———————— ——— сазына биінен A HISTORICAL SUMMARY. 3 and on the 7th day of the same month landed at Kyaukka Myo. On arrival he lost no time in fulfilling his desire of visiting the wonders of the place. On the 8th, on returning from one of these - excursions in the evening, he discovered that seven of the ladies, named the Myozas! of Nyoungók, Nyoungywe, Sale, Talin, Kyabin, Popa and Nyoungyan, and the eunuch Kye Pónna of his establish- ment were missing. He was much enraged, and immediately went in search of them. He reached a hill called Thuwanagiri, and there tarried for the night, being entertained by a Zawgyi (=magician) WE who resided there: hence this hill is called Minlindoung to this Мы dey. The next morning, the oth, he discovered the truants in r Н high glee on the banks of the lake of scented waters, and, enraged | at the sight, he killed them. They immediately turned into Nats.* When his passion had cooled down and he had meditated on the -crime he had committed, he blamed the Yenanthasi as being the cause of it. So, calling to his aid the miraculous powers which he | possessed, he changed the perfume of the waters into its present — malodorous state. From that day to the present it is known as 4 Қ. “Yenan” =stinking water. Оп ће roth the king attempted to leave 0 ИР y^ Kyaukka Myo, but none of its rafts would move; and on consulting ` his wise men was told that the natseins desired to be provided for and would not allow him to proceed till he had made provision for them. A meeting with the natseins was arranged, and an amicable settlement was come to, by which the king agreed that the proceeds of the sale of the Yenan were to be devoted to the eight nat- seins. The king also commanded that the Yenan producing soil be only within a certain area, which was to be held by the Yogas (viz., the descendents of the digger of the tank), and that the limits of such lands be laid down by drawing a straigbt line from a place 1 This might be translated “ duchesses " ; literally it means “ eater of the town,” because a Myotza derived his income from the revenue of the town that gave him his title. ER. 2 A kindof greenfaced demon; all who die of unnatural causes are very liable ko turn into a nat. ( 49 ) 4 NOETLING : PETROLEUM IN BURMA. called Thelagaza or Kyouksin (= Rock elephant) to Thawanagiri (= Minlindoung), then from the centre of this line to mark oft two points, one on the west at the same distance as from = centre to Minlindoung, and that the boundary be from Kyouksin to а point | east, thence to Minlindoung, thence to a point west, and thence to Kyouksin. After these commands the king was able to leave for Pagan, reaching it on the 14th of that month.” I may be permitted to dwell a little on this remarkable legend, because it contains a very Curious fact, of which an explanation is . highly difficult. At first the legend seems to prove the great age of the Yenangyoung oil-field. We may conclude that in remote times the Yenangyoung oil-field was systematically exploited and the oil used for all sorts of purposes. 222. А remarkable fact furthermore is the allusion to the 24 descend- ents of the man who first dug the tank, that they were to be the sole owners of the Yenan. In a later chapter it will be seen that 24 families claim the hereditary right of exploiting the oil. Of course this may bea subsequent addition to the original legend, recently inserted at the instigation of a crafty Twinzayo in order to give an ancient legendary background to their claims. The most remarkable part of the legend is the delimitation of. the area by the king. The magnetic bearing of the long axis of this tract agrees with the strike of the strata: in fact it coincides with ` ihe axis of the anticline. The recent borings have proved the limited extension of the Yenangyoung oil-field which falls rather short of the boundaries laid down by King Alaungsitha. | B.— Historical. Times. | I think there is hardly a volume of travels in Burma in which the Yenangyoung oil-field is not mentioned. The reason of this ЕС quite plain. Yenangyoung being оп the banks of the Irawadi, the highway of Burma, every traveller who visited Upper Burma ( 59.9 * HISTORICAL SUMMARY. | 5 à was bound to pass the famous place. It would be quite useless to ; ‚quote all the books in which the Yenangyoung oil-field has been ` mentioned: it is sufficient to refer to the most important works only. f The earliest account of the Yenangyoung oil-fields which í have 4 i been able to trace will be found in Captain { 1755. — со George Baker's Journal of an Embassy to the | | King of Burma in 1755;! he says: “ Raynan- Gome | take to lye 25’ South of Sallee-mue (=Salé Myo)...... At this Place there are about 200 Families, who are chiefly employed in get- ting Zarth-O:l out of Pitts, some five Miles in the Country. ” In 1782 W. Hunter, A. M. Surgeon, inthe employ of the Honour- able East India Company, who visited Burma, wrote as follows: “There is found here, swim- ming on the surface of the water in certain wells, a kind of petro- leum or naphta. which is used like oil for burning and also for mak- ing unctuous compositions for painting the sides of the vessels." The most reliable of the early accounts on the Burmese oil-fields willbe found in Symes Embassy to Ava, of which I give here an extract, omitting the less 1782. W. Hunter, - 1795. M, Symes.? |». important parts :— F . * The hills, or rather hillocks, were covered with gravel, and yielded no other vegetation than a few stunted bushes. The wheels (of the bullock carts) had worn ruts deep into the rock, which seem to be rather a mass of concreted gravel, than hard stone, and many pieces of petrified wood lay strewed about. It is remark- able, that wherever these petrifications were found, the soil was unproductive, and the ground destitute of verdure. The evening being far advanced, we met but few carts; those we did observe were drawn each by a pair of oxen, and of a length disproportionate to the breadth to allow space for the earthen pots that contained theoil. It wzs a matter of surprise to us, how they could convey such brittle ware, with any degree of safety, over so rugged a road : each pot was packed ina separate basket, and laid on straw, notwithstanding which precaution, the ground all the way was strewn with the frag ments of the vessels, and wet with oil; for no 1 Oriental Repertory, published at the charge of the East India Company, by . Dalrymple, London, 1791, page 172. 2 Michael Symes. An account of an Embassy to the kingdom of Ava, sent by the Governor-General of India in the year 1795. London, 1800, volume III, pages 232 ` to 258. ( 51. 6 NOETLING : PETROLEUM IN BURMA, care can prevent the fracture of some ir. every journey. As we approached the pits, which were more distant than we had imagined, the country became less un- even, and the soil produced herbage; it was nearly dark when we reached them, and the labourers had retired from work. There seemed to bea great many pits within a small compass : walking to the nearest, we found the aperture about 4 feet square, and the sides, as far as we could see down, were lined with timber; the | © oil is drawn up in an iron pot, fastened to a rope passed over a wooden cylinder 3 which revolves on an axis supported by two upright posts. When the pot is | filled, two men take the горе by the end, ала run down а declivity, which is cut in the ground, to a distance equivalent to the depth of the well; thus when they reach the end of their track, the pot is raised to its proper elevation, the contents, water and oil together, are then discharged into a cistern, and the water is after- wards drawn off through a hole at the bottom. Our guide, an active intelligent ў fellow, went to a neighbouring house and procured а well rope, by means of which we were enabled to measure the depth, and ascertained it to be thirty-seven ` fathoms, but of the quantity of oil at the bottom we could not judge: the owner of the rope who followed our guide affirmed, that when a pit yielded as much as came up to the waist of a man, it was deemed tolerably productive; if it reached to his neck, it was abundant; but that which rose no higher than the knee, was accounted indifferent. When a well is exhausted, they restore the spring by cutting deeper into the rock, which is extremely hard in those places where the oil is produced. Government farm out the ground that supplies this useful com- modity; and it is again let to adventurers who dig wells at their own hazard, by which they sometimes gain, and often lose, as the labour and expense of digging are considerable, The ой is sold on the spot for a mere trifle; I think two ` or three hundred pots for a tackal or half-a-crown. The principal charge is incurred by transportation and purchase of vessels.” In the 3rd part of the Manual of Geology of India, rst edition, page 151, it is stated that Symes gives the number of wells as 500 and the annual yield as something like 56,000,000 viss (90,900 tons). I do not know where the author of the Manual obtained this statement: from, as 1 cannot find any reference to it in my copy of Symes' Embassy to Ava. Symes' description of the features of the country in allits brief- ness affords such a true picture of the dry, barren land around Yenangyoung that one might suppose the author had visited Yenang- young in our times—nota hundred years ago. There are still the same dusty roads worn by deep wheel tracks, strewn with pieces of broken earthen pots and saturated with spilt oil, and there are still the same creaking, shrieking carts coming from the oil-fields while (504 oe 39 | Ga = t ` 4 š "RR oe چ‎ А “^з < U E еЗ HISTORICAL SUMMARY, | 7 Í write these lines, as they did a hundred years ago. But the most striking feature in Symes' account is the description of the wells, the method of extracting the oil, and the way of carting it down to the shore. In all this there has not been the slightest change, everything is exactly as it was a hundred years ago, only that now-a- days clay pots are used for hauling up the oil; in fact, I rather believe that this was also the case during Symes' visit, and that the “iron” pot which he noticed was an exception. The whole description of the oil-fields is, however, not so exhaus- tive as'it might be, and, if seen in the light of a report written only two years later, some of Symes' statements have to be accepted withthe greatestcare. In the first place it cannot be made out which of the two tracts—Bemé or Twingon--was visited by Symes. As Captain Cox particularly mentions two distinct oil-fields, I cannot imagine that within such a short time as two years a second oil-field with quite a number of wells could have sprung up. I believe, however, that Symes visited Bemé, as all his successors did. The next statement refersto the proprietary rights in the land. Symes' statements are too vague, and are contradicted altogether by the report of Captain Cox, whose statements have been independ- ently confirmed by the descriptions of subsequent visitors. It is hardly possible that such wide reaching changes in the proprietary ` : rights of the oil bearing land could have happened within two years, and we shall presently see that Captain Cox’s statements deserve much more credit, even had they not been confirmed subsequently. As regards the number of wells, Symes is certainly wrong. There cannot possibly have been 500 wells in existence, as the survey of 1890-91 has proved that there were then 602 wells all told, of which at least 76 have been constructed during the three preceding years, 120 more wells are certainly not older than 35 years. This reduces their number to 304, if we assume that no new wells have been dug between 1797 ana 1855, As this is, however, not very probable, we are obliged to assume that at the time when Cox visited the oil- ( 53 ) , 8 NOETLING : PETROLEUM IN BURMA. fields the number of wells was even smaller than 300. I shall. re- turn to this subject in a following chapter. The statement about the production must necessarily be equally exaggerated, even if we suppose that the average yield per well was higher in those days than it is now. The next report about the Yenangyoung oil-field was written only two years later by Captain Cox, who visited the oil-fields in 1797. The account of his visit was published in the Asiatic Re- searches (Volume VI, pages 127 to 136, 1799), and as it is highly interesting in many ways, I give it here verbatim: — * An ACCOUNT of the PETROLEUM WELLS in the BURMESE Doma ех- tracted from the Fournal of а voyage from RANGHONG up the River ERAI WUDDEY to AMARAPOORAH, the present Capital of the BuRMBA Empire by Captain Hiram Cox, Resident at RANGHONG. * Saturday, 7th Fanuary 1797- “Wind easterly, sharp and cold, thick fog on the river until after sunrise, when it evaporated as usual, but soon after collected again, and continued so dense till 8-30 A.M. that we could barely see the length of the boat. “Thermometer at sun rise 52°, at noon 74°, in the evening 69°. Genera] - course of the river north 20° west, main breadth from 1 to 12 miles ; current about 21 miles per hour. “ East bank, high rugged barren downs, with precipitous cliffs towards the river, of free stone intermixed with strata of quartz, martial ore, and red ochre; beech moderately shelving covered with fragments of quartz, silex, petrifactions and red ochre, with rocky points projecting from it into the river. * Western bank, a range of low sandy islands, covered with а luxuriant ` growth of reeds. These at present narrow the stream to three quarters and in some places to half a mile, but are overflowed in the rains ; the main bank rather low and sandy, subject to be overflowed, its whole breadth about 3 miles to the foot of a range of low woody hills, which in point of vegetation form an agreeable contrast to the eastern shore. These hills are bounded to the westward at the distance of about 20 miles from the river by an extensive range of high moun- tains, cloathed with wood to their summits. * At half past ten A.M. came to the lower town of Rainanghong, a temple in it of the antique Hindoo style of building. At noon came to the centre town of Rainanghong (literally the town through which flows a river of earth oil), situated on the east bank of the river in latitude 20? 26! north and longitude 94? 45! 54" east of Greenwich, halted to examine the wells of Petroleum. “The town has but a mean appearence, and several of its temples, of which there are great numbers, falling to ruins: the inhabitants however are well dressed, many of them with gold spiral ear ornaments, and are undoubtedly rich from the great profit they derive from their oil wells, as will be seen below. P 54 ) HISTORICAL SUMMARY. 9 * At two р.м. I set off from my boat, accompanied by the mewthaghee or zemindar of the district and several of the merchant proprietors, to view the wells. Our road led to E.N.E. through dry beds of loose sand in the water-courses, and over rugged arid downs and hillocks of the same soil as described above, the growth on them consisting of scattered plants of Euphorbium, the Cassia tree which yields the Terra Japonica, commonly. called cutch or cuth, and used throughout /zdia asa component part of a beera of paun, also a very durable timber for lining the oil wells, and, lastly, the hardy bair or wild plumb common - jn Hindustan. “The sky was cloudless, so that the sun shone on us with undiminished ` force, and being also unwell, I walked slowly, and as we were an hour walking to the wells, 1 therefore conclude they are about three miles distant from the river ; those we saw are scattered irregularly about the downs, at no great distance from each other, some perhaps not more than 30 or 40 yards. At this particular place we were informed there are 180 wells, four or five miles to the N.E. 340 more. * In making a well the hill is cut down so as to form a square table of fourteen or twenty feet for the crown of the well, and from this table a road is formed, Ьу scraping away an inclined plain for the drawers to descend in raising the excavated earth from the well, and subsequently the oil. The shaft is sunk in a square form, and lined, as the miner proceeds, with squares of Cassa wood staves. These staves are about six feet long, six inches broad, and two thick; are rudely jointed and pinned at right angles to each other, forming a square frame about four and a half feet in clear for the uppermost ones, but more contracted below. When the miner has pierced six or more feet of the shaft, a series of these square frames are piled on each other, and regularly added to at top, the whole gradually sinking, as he deepens the shaft, and securing him against the falling in of the sides. “ The soil or strata to be pierced is nearly such as I have described-the cliffs to be on the margin of the river, that is, first, a light sandy loam intermixed with fragments of quartz, silex, etc. ; second, a friable sand stone, easily wrought, with thin horizontal strata of concrete or martial ore, talc, and indurated argill (the latter has this singularity, it is denticulated, its lamina being perpendicular to the horizontal lamina of the argill on which it is seated) at from ten to fifteen feet. from the surface, and from each other, as there are several of these veins in the great body of free stone. Thirdly, at seventy cubits, more or less, from the surface, and imme- diately below the free stone, a pale blue argillaceous earth (shistous) impregnated with the petroleum and smelling strongly of it. This they say is very difficult to work, and grows harder as they get deeper, ending in schist and slate, such as found covering veins of coal in Europe, etc. Below this schist at the depth of about 130 cubits is coal. I procured some, intermixed with sulphur and pyrites which had beentaken from a well deepened a few days before my arrival, but deemed - amongst them a rarity, the oil in general flowing at a smaller depth. They were piercing a new well when I was there, had got to the depth of eighty cubits, and expected oil at ten or twenty cubits more. * The machinery used in drawing up the rubbish, and afterwards the oil from КЕЗГІ? ХО NOETLING: PETROLEUM IN BURMA, the well, is an axle crossing the center of the well, resting on two rude-forked stanchions, witha revolving barrel on its center, like the nave of a wheel, in which is a score for receiving the draw rope, the bucket is of wicker work, covered with dammer, and the labour of the drawers, in general three men, is facilitated by the descent of the inclined plain, as water is drawn from deep wells in the interior of Hindostan. ӘР * To receive the oil, one man is stationed at the brink of the well, who empties the bucket into a channel made on the surface of the earth leading to a sunk jar, from whence it is ladled into smaller ones, and immediately carried down tothe ` river, either by coolies or on hackeries. * When a well grows dry, they deepen it. They say none are abandoned for barrenness. Even the death of a miner, from mephitic air, does not deter others from persisting in deepening them when dry. Two days before my arrival a man was suffocated in one of the wells, yet they afterwards renewed their at- tempts without further accident. 1 recommended their trying the air with a can- dle, etc., but seemingly with little effect. “ The oil is drawn pure from the wells, in the liquid state as used, without variation, but in the cold season it congeals inthe open air, and always loses some- thing of its fluidity ; the temperature of the wells preserving it in a liquid state fit to be drawn. A man who was lowered into a well of 110 cubits, in my presence, and immediately drawn up; perspired copiously at every pore; unfortunately I had . no other means of trying the temperature. Тһе oil is of a dingy green and odor- ous; itis usedfor lamps and boiled with a little dammer (a resin of the country) for painting the timbers of houses, and the bottoms of boats, etc., which it preserves from decay and vermin ; its medicinal properties known to the natives is as a lotion in cutaneous eruptions, and as an embrocation in bruises and rheumatic affections. “The miners positively assured me no water ever percolates through the earth into the wells, as has been supposed, the rains in this part of the country are seldom heavy, and during the season a roof of thatch is thrown over the wells ; the water that falls soon runs off to the river, and what penetrates into theearth is effectually prevented from descending to any great depth by the increasing hard- ness of the oleagenous argill and shist; this will readily be admitted, when it is known that the coal mines at Whitby are worked below the harbour, and the roof of the galleries not more than fifty feet from the bed of the sea, the deficiency of rain in this tract may be owing tothe high range of mountains to the westward, | | which range parallel to the river and arrest the clouds in their passage, аз is the E | case on the eastern side of the peninsula of India. "n * Solicitous to obtain accurate information on a sübject so interesting as this natural source of wealth, I had all the principal proprietors assembled on board | my boat, and collected from them the following particulars, the foregoing I learned at the wells from the miners and others. | “I endeavoured to guard against exaggeration, as well as to obviate the caution and reserve which mercantile men in all countries think it necessary to observe, when minutely questioned on subjects affecting their interests, and I have to hope my information is not very distant from the truth. 6; 86 Q HISTORICAL SUMMARY, - 11 “ The property of these wells is in the owners of the soil, natives of the coun- try, and descends to the heirs generally as a kind of entailed hereditament, with which it is said Government never interferes, and which no distress will induce them to alienate. One family perhaps will possess four or five wells, 1 heard of none who had more,the generality have less, they are sunk by, and wrought for, the proprietors; the cost of sinking a new well is 2000 tecals flowered silver of the country, or 2500 sicca rupees ; and the annual average net profit rooo tecals, or ` 1250 sicca rupees. “The contract price with the miner for sinking a well is as follows : for the first forty cubits they have forty tecals, for the next forty cubits three hundred tecals, and beyond these eighty cubits to the oil they have from thirty to fifty tecals per cubit, according to the depth (the Burmha cubit is nineteen inches English); taking the mean rate or forty tecals per cubit and one hundred cubits as the general depth at which they come to oil, the remaining twenty cubits will cost 800 tecals, or the whole of the miner’s wages for sinking the shaft 1140 tecals; a well of roo cubits will require 950 cassia staves, which at 5 tecals per hundred will cost 47% tecals. Portage and workmanship, in fitting them, may amount to 100 tecals more ; the levelling the hill for the crown of the well, and making the draw road, etc, according to the common rate of labour in the country, will cost about 200 tecals, ropes, etc., and provisions for the workmen which are supplied by the proprietor when making a new well; expenses of pro- pitiatory sacrifices, and perhaps a signiorage fine to government for permission to sink a new well consume the remaining 5123 tecals. In deepening an old well they make the best bargainintheir power with the miners, who rate their demand per cubit according to its depth, and danger from the heats or mephitic air. “The amount, produce, and wages of the labourers who draw the oil, as stated to me, I suspect was exaggerated or erroneous from misinterpretation on both sides. * The average produce of each well per diem, they said, was soo viss or 1825 lbs. avoirdupois, and that the labourers earned upwards of eight tecals each per month, but I apprehend this was not meant as the average produce or wages per every day or month throughout the year, as must appear from further examina- tion on the subject, where facts are dubious we must endeavour to obtain truth from internal evidence. Each well is worked by four men, and their wages is regulated by the average produce of six days' labour, of which they have one sixth, or its value at the rate of one and a quarter tecals per hundred viss, the price of the oils at the wells ; the proprietor has an option of paying their sixth in oil, but I understand he pays the value in money, and if so, I think it is as fair a mode of regulating the wages of labour as anywhere practised, for in proportion, as the labourer works he benefits, and gains only as he benefits his employer. He can only do injury by over-working himself, which is not likely to happen to an Indian ; no provisions are allowed to the oil drawers, but the proprietor supplies the ropes, etc. and lastly the king's duty is a tenth of the produce. “Now, supposing a well to yield 500 viss per diem throughout the year, deduct= ing one sixth for the labourers and onetenth for the king, there will remain for the ESE) .12 NOETLING : PETROLEUM IN BURMA. proprietor, rejecting fractions, 136,876 viss, which at 12 tecals, the value at the wells, is equal to 1710 tecals per annum. From this sum there is to be deducted only a trifle for draw ropes, etc., for I could not learn that there was any further duties or expense to be charged on the produce, but the merchants say they gain only a neat 1000 tecals per annum for each well, and as we advance we shall have reason to think they have given the maximum rather than the minimum of their profits, hence, therefore, we may infer that the gross amount produce per annum is not 182,500 viss, * Further the four labourers’ shares ot onesixth deducting the king's tythe, will . be 2250 viss per month of thirty days or in money at the above price twenty-eight tecals fifty avas, or seven tecals twelve avas each per man per month, but the wages of a common labourer in this part of the country, as the same persons informed me, is only five tecals per month when hired from day to day; they also admitted that the labour of the oil drawers was not harder than that of common labourers, and the employment was in no way obnoxious to health. To me the smell of the oil was fragrant and grateful, and on being more indirectly questioned (for on this part of the subject perhaps owing to the minuteness of my enquiries 1 observed most reserve; they allowed that their gain was not much greater than the common labourers of the country, nor is it reasonable to expect it should, for, as there is no mystery in draw- ing of oil, no particular hardships endured, or risk of health, no compulsion or pre- | vention pretended, and, as it is the interest of the proprietors to get their work done at the cheapest rate, of course the numbers that would flock to so regular and profitable an employment would soon lower the rate of hire nearly at least to the common wages of the country ; besides I observed no appearance of affluence amongst the labourers, they were meanly lodged and clad, and fed coarsely, not on rice, which in the upper provinces is an article of luxury, but on dry grains and indigenous roots of the nature of Cassada, collected in the wastes by their women and children; further it is not reasonable to suppose that these labourers worked con- stantly, nature always requires a respite, and will be obeyed, however much the desire of gain may stimulate, and this cause must more particularly operate in warm climates to produce what we often improperly call indolence. Even the гісі Cato emphatically says, that the man who has not time to be idle is a slave. A due consideration of this physical and moral necessity ought perhaps to vindicate religious legislators from the reproaches too liberaliy bestowed on them for sanc- tioning relaxation; be that asit may, I think it is sufficiently apparent that the article of wages is alSo exaggerated, and that 500 viss must only be considered as the amount produce of working days, and not an average for every day in the year. The labour of the miners, as I have observed above, is altogether distinct from the oil drawers, and their pay proportioned to the hardships and risks they endure, * Assuming therefore as data, the acknowledged profit of 1000 tecals per . annum for each well, which we can hardly suppose exaggerated, as it would expose the proprietors to an additional tax, and the common wages of precarious | employment in the country, that is one month with another, including holy days ` the year round, four and a quarter tecals per month as the pay of the oil drawers, which includes the two extremes of the question, it will make the average produce of e. : 3 4 HISTORICAL SUMMARY. | 13 each well per diem, 300 viss or 109,500 viss per annum, equal to 399,675 lbs. avoirdu- pois ortons 178,955 lbs.* or in liquid measure 793 hogsheads of sixty three gallons each, and as there are 520 wells registered by Government, tbe gross amount produce of the whole per annum will be 56,940,000 viss or 92,781 tons, 1,560 lbs. or 412,360 hogsheads, worth at the wells, at one and a quarter tecals per hundred viss, 711,750 tecals, or 889,737 sicca rupees. * From the wells, the oil is carried, in small jars, by coolies, or on carts, to the ` river ; where it is delivered to the merchant exporter at two tecals per hundred viss, the value being enhanced three-eighths by the expense and risk of portage, therefore - the gross value or profit to the country of the whole, deducting five per cent. for wastage, may be stated at 1,081,860 tecals or 1,362,325 sicca rupees per annum, yielding a direct revenue to the king of 136,232 sicca rupees per annum, and per- haps thrice as much more before it reaches the consumer; besides the benefit the whole country must derive from the productive industry called into action by the constant employment of so large a capital on so gruff an article. There were between Seventy and eighty boats, average burthen sixty tons each, loading oil at several wharves, and others constantly coming and going while I wasthere. A number of boats and men also find constant employment in providing the pots, etc., for the oil, and the extent of this single branch of internal commerce (for almost the whole is consumed in the country) will serve to give some insight into the internal commerce and resources of the country. * At the wells the price of the oil is seven annas six pies per 112 lbs. avoirdupois; at the port of Rarghong it is sold at the average rate of three sicca rupees three annas six pies per cwt., or per hogshead of sixty three gallons weighing: 504 lbs. fourteen rupees five annas eight pies, exclusive of the cask, or per Bengal buzar maund two rupees five annas eight pies, whereas the mustard seed, and other vegetable oils, sell at Ranghong at eleven rupees per buzar maund. «Го conclude, this oil is a genuine petroleum, possessing all the properties of coal tar, being, in fact, the self same thing, the only difference is, that nature ela- borates in the bowels of the earth that for the Burmhas, for which European nations are obliged to the ingenuity of Lord Dundonald." \ This report is a source of the most useful information about the oil-fields in those days. Most of the observations are correct, and have been confirmed by later observers. He went nearly into every detail; in fact, he deals so exhaustively with the subject that hardly anything remains to be added. There are of course some mistakes such as, when describing the timbering of the shafts, he says that the wooden square frames forming the casing of the pit are added at the top of the well, the whole gradually sinking as the well is deepened. A little reflection would have shown that this was im- possible, the friction between the timber casing and the rocks being 1 Sic. in orig. ( 59) 14 NOETLING: PETROLEUM IN BURMA. so great that it would be quite impossible for the casing to sink by its own weight. But, apart from small mistakes like this, Captain Cox's report is as accurate as possible, and, if it was not for the erroneous statement about the number of the wells and the rather mysterious statement of two towns of Yenangyoung, a lower and a centre one, separated a distance of 1% hours of each other, the report would be a model of correctness, _ It is impossible for me to find out what Captain Cox meant by the lower and the centre town of Rainanghong, the latter one is evi- dently the present Yenangyoung, but I cannot possibly make out what is meant by the lower town : perhaps it was Nyaunghla. Captain Cox visited Bemé, as he distinctly states that there is another group of wells to the north-east of the one he visited. As Twingon lies to the north-east of Bemé oil-field, it is undoubtedly that itis the latter one he saw, although he greatly overrates the distance between both tracts. He also greatly overestimates the number of wells. There can- not possibly have been 520 wells in 1797, for the reasons which I have pointed out before, if we do not accept the highly improbable theory that 200 wells have been so perfectly filled up again that no trace of them can now be discovered, Hisdescription of the wells, their method of digging, and the extraction of the oil, is perfectly correct, and could have been writ- ten in our times. The statements about the proprietary rights in the wells are the _ more interesting, as here for the first time the “families of heredi- | tary wellowners" a e mentioned, which have in these days, as twinzas and twinzayos, become of some importance. The statements about duty, wages, and price of the oil are highly valuable, but the amount of the production must necessarily be | greatly overrated, as it is based on the assumption of 520 wells each - producing in the average 300 viss per day. ( 60 ) HISTORICAL SUMMARY, 15 The next who wrote about the Yenangyoung oil-fields is = Mr. Crawfurd, who visited the oil-fields in 1826. The following is Ж the description һе gives! :— “ At three in the afternoon our whole party proceeded to the celebrated pe- troleum wells. Those which we visited cannot be further than three miles from the village, for we walked to them in forty minutes. The cart-road which leads to them is tolerably good, at least for a foot traveller. The wells occupy altogether a space of about sixteen square miles. The country here is a series of sand hills and ravines, — the latter, torrents after a fall of rain, as we now experienced, and the former either covered with a very thin soil, or altogether bare. The trees, which were rather more numerous than we looked for, did not rise beyond twenty feet in height. The | surface gave по indications that we could detect of the existence of the petroleum. ` Оп the spot which we reached, there were eight or ten wells, and we examined one | of the best. The shaft was of a square form, and its dimensions about four feet to a side. It was formed by sinking a frame of wood, composed of beams of the Mimosa catechu, which affords a durable timber. Our conductor, the son ofthe z Myosugi, of the village, informed us that the wells were commonly from one hundred and forty to one hundred and sixty cubits deep, and that their greatest depth in any case was two hundred. He informed us that the one we were examining was the D private property of his father — that it was considered very productive, and that 4 қ its exact depth was one hundred and forty cubits. We measured it with a good we, lead line, and ascertained its depth to betwo hundred and ten feet ; thus corre- ; sponding exactly with the report of our conductor—a matter which we did not look Е ` for, considering the extraordinary carelessness of the Burmans in all matters of k this description. A pot of the oil was taken up, and a good thermometer being | immediately plunged into it, indicated a temperature of ninety degrees. That of ‘ B the air, when we left the ship an hour before, was eighty two degrees. To make кот the experiment perfectly accurate, we ought to have brought a second thermometer Е, - along with us; but this was neglected. We looked into one ог two of the wells, | and could discern the bottom. The liquid seemed as if boiling; but whether from the omission of the gaseous fluids, or simply from the escape of the oil itself from the ground, we had no means of determining. The formation, where the wells are sunk, consisted of sand, lose sandstone, and blue clay. When a wellis dug to 'a considerable extent, the labourers informed us that brown coal was occasionally found. Unfortunately we could obtain no specimens of this mineral on the spot, but I afterwards obtained some good ones in the village. The petroleum itself, when first taken out of the well, is of a thin watery consistence, but thickens by keeping, ЧАА; and in the cool weather coagulates. Its colour, at all times, is a dirty green, not = p much unlike that of stagnant water. It has a pungent aromatic odour, offensive E to most people. The wells are worked by the simplest contrivance imaginable. There is over each well a cross beam, supported by two rude stanchions. At the | Ë 1826, Crawfurd. > 1 Journal of an Embassy from the Governor-General of India to the Court of Ava in 1827 4° London, 1829, p. p. 53—56, 427, and 445. | с, ЖЗ 16 | NOETLING : PETROLEUM IN BURMA, centre of the cross-beam, and embracing it, is a hollow revolving cylinder, with. a channel to receive a drag-rope, to which is appended a common earthen pot that is let down into the well, and brought up full by the assistance of two persons pulling the rope down an inclined plane by the side of the well. The contents of the pot - are deposited for the time in a cistern. Two persons are employed in raising the oil, making the whole number of persons engaged on each well, only four. The oil is carried to the village ‘ог put in carts drawn by a pair of bullocks, each cart conveying from 10to 14 pots of 10 viss each, or from 265 to 371 pounds avoir- dupois of the commodity. The proprietors store the oilin their houses at the village, and there vend it to the exporters. The price, according to the demand, varies from four tecals of flowered silver, to six tecals per 1000 viss, which is from five pence to seven pence half penny per cwt. The carriage of so bulky a commo- dity, and the breakage to which the pots are so liable, enhance the price, in the most distant parts to which the article is transported, to fifty tecals per 1000 viss....... | еБаы 15 usel by the Burmans for the purpose of burning in lamps, and smearing timber to protect it against insects....... The quantity exported to foreign parts is a mere trifle, not worth noticing. Itis considered that a consumption of thirty viss per annum, for each family of five and a half persons, is a moderate average... | | “..... Т made such enquiry into the nature of the trade as my short stay would admit. The number of boats waiting for cargoes of oil was correctly taken, | and found to amount to one hundred and eighty three, of very various sizes, some carrying only one thousand viss, others fourteen thousand. According to the Burmese, whom I consulted, the average burthen of the vessels employed in this traffic, was considered to be about four thousand viss. The number now mentioned is not considered unusual; and it has been reckoned that, one with another, they complete their cargoes in fifteen days ; they are therefore renewed 24 times in the course of the year; and the exportation of oil according to this estimate will be 17,568,000 viss....... “ Of the actual produce of the wells, we received accounts not easily reconcil- able to each other....... The daily produce of the wells was stated, according to goodness, to vary from thirty to five hundred, the average, giving about two hundred and thirty five viss ; and the number of wells was sometimes given as low as fifty, and sometimes as high as four hundred. The average made about two hundred ; and considering that they are spread over sixteen square miles, as well as that the oil is well known to be a very general article of consumption throug hous the country, I do not think this number exaggerated. ”’...,.. “ The celebrated petroleum wells afford, as I ascertained at Ava, а revenue | to the King or his officers. The wells are private property, and belong here- ditarily to about thirty-two individuals. A duty of five parts in one hundred is levied upon the petroleum as it comes from the wells, and the amonnt realized upon it is said to be twenty-five thousand tecals per annum. No less than twenty thousand of this goes to contractors, collectors, or Bulle officers; and the share ph sz.) HISTORICAL SUMMARY. 17 of the state, or five thousand, was assigned during our visit as a pension of one of the Queens” „..... (page 427). ` “From the more accurate information which I obtained at Ava, it appears that the produce of these may be estimated at the highest, in round numbers, at about twenty-two millions of viss, each of 3.65; pounds, avoirdupois. This esti: mate is formed from the report of the Myo-Thuggi, who rents the tax on the wells, which is five in hundred. His annual collection is 25,000 tecals, and he estimated or conjectured that he lost by smuggling about 8,000, making the total 33,000. The value of the whole produce, therefore, is 660,000 tecals. The value of the oil on the spot is reckoned at three tecals per hundred viss, and consequently its amount will be as above stated.” The statement in this account that the wells extend over an area of 16 square miles is curious, seeing that, allowing a very liberal margin, the oil-fields cover an area of only 343 acres, or a little over half a square mile. The estimate of the outturn can hardly be considered of much value, having been arrived at in rather a sum- mary way, particularly as regards the export of oil from Yenang- young. In fact, Crawfurd's reports contain less information about the condition of the Burmese oil-fields, than Captain Cox's de- scription, although the latter had been made 30 years previously. In 1835 Captain Hannay visited the oil-fields. Unfortunately I have no access to his manuscript, but his, state- 1835, Captain Hannay. , I % ment of an annual production of 93,000 tons _ seems exaggerated. It isa pity that Captain McLeod’s manuscript on the oil-fields, which he visited in 1838, formerly kept in the | Foreign Office, and quoted by Captain H. Yule, has never been published, as it appears to have contained some valu- able information. Captain McLeod states the number of wells as not higher than 160, which for various reasons I believe to be nearly correct; but he certainly underestimates the average yield per well, namely, 36 viss per day. Even now, although the fields are not so productive, the average is higher, and we may conclude that it was still higher 52 years ago. The next description added much to a knowledge of the oil-fields. c | iu . Captain McLeod, 1838. 18 NOETLING : PETROLEUM IN BURMA, It is contained in Captain (afterwards Sir Henry) Yule's account of the Mission to Ava! in 1855, in which two members of the Mission, Captain Yule and Dr. Oldham, give their observations, and as they are of great importance, I give both accounts in extenso. The following is Captain: Yule's description :— Captain Yule, 1855. “We started early to visit the earth-oil wells, or mines, as they might be | called....... Our road wound about among the ravines and up the steep sides of the rotten sandstone hills, till, about three miles from the town, we came upon the plateau on which the principal wells are situated. It is an irregular table with a gently rising surface, forming a sort of peninsula among the ravines. * The wells are frequent along its upper surface, and on the sides and spurs of the ravines which bound it on the north and south-east, They are said to be about a hundred in number, but of these some are exhausted or not worked. The depth of the wells appeared to vary in tolerable proportion with the height of the well-mouth above the river level, but an inspection of the lowest, situated near е? ' bottoms of the ravines, enabled us to ascertain that all were sunk a good deal below the level of the ravine bottoms which bounded the plateau. Those that we measured (by pacing the length of the rope used) on the top of the plateau were | -180 feet, 190 feet, and 270 feet in depth to the oil. One was said to be 20 cubits deeper than this last, which would give a depth of about 306 feet. * As far as wé could judge, the area within which these wells stand does not exceed half a square mile. The wells are in some places pretty close together ; less, that is to say, than a hundred feet apart. They are all exactly alike in appearance; rectangular orifices about four and a-half feet by three and a-half, and lined with horizontal timbers the whole way down. The oil appears to be found in a stratum of impure lignite, with a good deal of sulphur. In one of the valleys we saw a stratum of this out-cropping, with the oil oozing between the laminz. Doubtless, it was in this way originally discovered ; some Burman, with a large inductive faculty, having been led to sink a shaft from above. * A rude windlass, mounted on the trunk of a tree, laid across two forked stems, is all the machinery used. An earthen pot is let down and filled, and then a man or woman walks down the slope of the hill with the rope. There is another ‚group of oil-wells in a valley about a mile to the southward. | ‘Ihe petroleum from these pits is very generally used as a lamp-oil all over Burma. It is also used largely on the wood-work and planking of houses, as a preservative from insects, and for several minor purposes, as a liniment, and even a medicine taken internally. The Chinese Geography, translated in Thevenot's Voyages curieux, says that it is a sovereign remedy for the itch, which its sulphur- ous affinities render highly Ss. There is now a d ade CERE of the 1 A narrative of the Mission sent by the Governor-General of India to the ves of Ava in 1855, with notices of the country, PME M and people. General report by Captain H. Yule; Geological Report by Dr. Oldham : 4 London 1858, pages 19—22. | E HISTORICAL SUMMARY, 19 ` . article from Rangoon to England, and one of the Rangoon houses had a European agent residing on the spot. The demand in England is, [ believe, for use to some extent as a lubricating oil, but it is also employed by Price's Company at Lambeth in the manufacture of patent candles, and has been found to yield several valuable products. It һа sold in the London market at from £40 to £45 a ton. “ The oil itself looks like thin treacle of a greenish colour, and the smell is not unpleasant in the oper air, and in moderate strength. “Тһе northern group of wells contains, as well as could be learned, about 80 wells now yielding oil. The southern group contains about 50, which yield an inferior kind of oil mixed with water. At either place there are many exhausted wells. Each group occupies a space of about half a square mile or somewhat less, There appears to be no record or tradition as to the original discovery of the petroleum, or as to the lapse of time since it was first worked. The wells are private property, the ground they occupy being owned by 23 families, inhabitants of Yenangyoung, and the representatives, itis believed, of those who first dis- covered and worked the petroleum. Among these is the hereditary Myo-thoo- gyee of the place, who holds at present the office of Myit-tsin-woon or chief magis- trate of the great river, They do not allow any stranger to dig a well; and al- _ though a respectable owner stated that they had no written grant or confirmation of their exclusive privilege, yet it is upheld by the local Burmese authorities, and apparently they have sufficient influence to prevent any wells being dug by inter- lopers in the vicinity of their groups or clusters of wells. But, independently of the influence they thus exert to prevent any interference with their privileges and profits, the great expense in the present dearth of capital, and the uncertainty of return, prevents any one trying seriously to compete with them. The twenty-three proprietors constitute a kind of corporate body, as regards their joint interests in the land, but possess individual property in their own wells. When once a well has been dug, no one else is allowed to dig within 30 cubits of it. No proprietor is allowed to sell or mortgage his well to anyone not a proprietor. They mortgage them among themselves. Formerly they intermarried among themselves only ; - but, latterly, an old and respectable proprietor informed Major Phayre, this custom ` had been broken through by the * young people,’ / “The cost of digging a well 150 cubits deep was said to be 1,500 to 2,090 tecals, sometimes even more ; and after all, the money might be thrown away, asa ` well dug within a few yards of others yielding a good male often proves a failure. The work cf excavation becomes dangerous as the oily stratum is approached, and frequently the diggers become senseless from the exhalations. This also happens in wells that have been long worked. ‘If a man is brought up to the surface with occasionally his tongue hanging out,’ said one of our informants, ‘it is a hopeless case. If his tongue is not hanging out, he can be brought round by hand-rubbing and kneading his body all over.’ ** The yield of the wells varies greatly. Some afford no more than five or six viss, whilst others give 700, 1,000, and even, it is said, 1,500 daily. From all that we could learn, thé average yield of the wells in the northern group to be 40 viss. Generally the supply from a well deteriorates the longer it is worked. And if it be allowed to be fallow for a time, it is said that the yield i is found to be diminished on the recommencement of the work. C 2 | Pos N, ` 20 NOETLING: PETROLEUM IN BURMA. * The oil is described by the people as gushing like a fountain from openings in the earth. It accumulates in the well during the afternoon and night, and is drawn off in the morning. The proprietors have the oil conveyed to the river side in carts loaded with earthen pots containing ten viss each. “The ordinary price of the article used to be one tecal the hundred viss, or about sixteen shillings aton. Lately, in consequence of the demand from Rangoon, it has risen to about thirty-five shillings a ton. * As to the amount of revenue derived by the King from the petroleum we ` found it difficult to get definite information. One intelligent proprietor, who was a Myo-ok of the town, stated that out of the 27,000 viss, which formed the whole monthly yield of his wells, 9,000 went in payment to the work-people, 1,000 to the King, and 1,000 tothe lord of the district. “It is an object: of some interest to endeavour to ascertain the approximate amount of petroleum yield by these wells. There was not time to make very minute enquiries on this head, not to mention that questioning closely every pro» prietor might have given umbrage to the Burmese officers, and excited their jea- lousy. From the information derived, however, from the proprietors who came to the Envoy, and from general enquiries by other members of the Mission, it appears that there are in the northern group of wells about 80 yielding oil. This would give, at the daily average of 220 viss from each well, an annual amount of 6,424,000 viss drawn from the northern group. “The 50 wells of the southern group are assumed to yield on the average 40 viss each daily. Their yield, therefore, annually, would be 730,000 viss, mak- ing a total quantity of 7,154,000 viss annually, equal to about 11,690 tons, This is very nearly what the Myo-ok stated the produce to be, and it was, in all pro- bability, about the truth.” Excepting some small inaccuracies this account is undoubtedly very correct, and it is the more important, as it gives for the first time definite information about the rights and customs of the 23 twinzayo families. In fact, Captain Yule has given in this short description all that has come out [during the long enquiries held lately about the customs and rights of the twinzayos, His | evidence is the more important, because it is not influenced by the various interests of the present times, which lead the Burman to make only such statements as seem to be most profitable to him- self, In Captain Yule's description we find the same difficulty which we encountered in previous accounts. It is difficult to say which of the two oil-fields he visited. The illustrative view of the oil-field at Yenangyoung accompanying the description is difficult to | recognize. It was only quite accidentally that I hit on the very spot (06) HISTORICAL SUMMARY, ; 21 from which the view was taken ; it lies a little to the south of well No. 594 (Bem?) on the top of the hill, the spectator looking towards west, that is to say, towards Yenangyoung. In this view the pagoda to right represents the big pagoda just west of Bemé, the village in the centre is Bemé and the hill right in the centre of the back ground is Minlindoung, the highest hill in this part of the country. There is therefore no doubt that the view of the “ oil-wells at Yenangyoung " represents the view of the southern part of the Bemé oil-tract, seen from the east; and we may therefore assume that the party certainly visited Bemé, but whether they also went to Twingón is difficult tosay. From the above description one might be led to believe that Twingón only was visited, but the picture of the landscape agrees with the natural aspect of the Bemé tract. As regards the number of wells, Captain Yule states іп “һе beginning of the description that they are “about a hundred in number,” but whether this applies to the total or only to the wells of a single group cannot be made out. He afterwards states that there are 80 wells in the northern and 5o in the southern group, that is to say, 130 in the aggregate. His estimate _ ОЁ the annual production seems to be fairly correct, although it is astonishing that 36 years ago the average daily production. of the Bemé wells should not have been more than 40 viss, while in 1888 it | Was 50'77 viss. I now give Dr. Oldham's account of the oil-fields (pp. 316—318) : * This may be a suitable place to make a few remarks on the abundance of ` the supply of the valuable product, earth-oil or petroleum. No absolute section of any of these wells could be obtained. In all cases they are carefully timbered up as the sinking proceeds, and this is continued from the top to the very bottom, so that no examination of the sides of a well or pit could be made. The soft and yielding nature of the materials through which the sinkings are made renders this necessary. And where they have not been successful in their adventure, or when the well or pit seems to be exhausted, all не timbering is removed again, and the whole allowed to fall in. * According to the natives, after passing through the sandstones and shales, visible at the surface and in the ravines adjoining, they sink through what they call a ‘black soil’ or “black rock.’ “ This, they say, is about то feet in thickness, and is obviously their name for _ the dark bluish-grey or blackish shales, or clunchy clay. | ET] ` 22 NOETLING: PETROLEUM IN BURMA. * Under this they cut through a yellow soil, and from this they state the petroleum issues. Between the black and the yellow rocks there is commonly, although not always, a greenish bed, oily, and strongly impregnated with petro- leum ; and this, in all probability, is nothing but the ordinary shaly clay, charged with oil. “The “yellow soil’ I fancy to be clayey beds, from which, or on which, sulphur has been segregated or thrown out, as an efflorescence. * The wells are put down vertically. They are square or rectangular in section, and about four feet six inches on each side. * Over each well across beam, supported on staunchions at either side, is placed, and onthe centre of this is a small wooden drum or cylinder, over which the rope used in hauling up the oil passes. Ë * A common earthenware gurrah, or pot, is attached to the rope, and, being lowered, is allowed partially to fill by sinking into the oil below, and is then drawn up by a man or men, who walk with the rope down an inclined plane at the side of the well. The oil thus raised is poured into another pot, or into a small basin excavated close to the well mouth, and from this is packed into gurrahs for con- veyance to the village for shipment. Each’cart conveys from то to 12 gurrahs, each gurrah holding about то viss of oil, or, on the average, тоо viss (365 lbs.) on each cart. The oil is raised only in the morning, and, the quantity which each well is known by experience to give having been raised, the work then ceases, and. the oil is allowed to accumulate during twenty-four hours. On the following morn- ing the process is repeated. The petroleum, when first extracted, has in mass a peculiar yellowish green coiour, is watery more than oily, and of the consistence of ordinary cream. | “From some of these wells 400 viss (1,416 lbs.) are extracted daily; one which we saw had, according to the statements of the natives, yielded this large amount daily for some months, and from it this quantity had that morning been taken. Others, again, only yielded 6o viss, or less ; while not unfrequently, after large expenditure in sinking and reaching what they consider the proper soil of the petroleum, the well will prove a failure and yield none. Тһе wells’ are in two principal groups, as mentioned above, which are nearly two miles apart. They have been sunk indifferently on the slopes of the deep ravines, and from the level plateau on top. They do not occur in any particular line or direction ; there is nothing to point to the occurrence of any fault or dis- turbance, along the line of which the petroleum might issue, and the varying depths of the wells themselves, according to their position (those on the top of the plateau being, in all cases, deeper than those on the slope of the hillside, and this, approximately, in the same ratio as the surface of the ground is higher in one place than in the other), indicate a tolerable horizontality in the source of supply. This is a question of'considerable importance ; for if it be the case that one bed or layer of peculiar mineral character is the source of the. petroleum, the ! One of the wells on the top of the plateau has a depth of 180 cubits (royal cubits—22 inches) and they range from 140 to 180, or from 250 to 330 feet; while those on the slope of the hill vary from roo to 60 cubits, according to position, or from 180 to 110 feet, while the bed of the stream or watercourse is trom 120 to 130 feet below the level of the plateau. TW rr HISTORICAL SUMMARY. 23 probability, nay, I would say, the certainty is, that the supply must be gradually diminishing. I could not learn that the number of the wells has been increased lately, while the demand for the product has increased more than fourfold, and is daily increasing. These facts are sufficient to account fully for the greatly enhanced price of the oil. The ordinary price of the petroleum, previously to the British annexation of Pegu, was at the village of Yenangyoung, from 10 annas to 14 annas per 100 viss. It has since increased from 1 rupee to 1-8 ; and an agent for a mercantile house at Rangoon, who was there at the time of our visit, stated that he had to pay even so much as 2 rupees 4 annas for 100 viss, At Rangoon, the price used to be from 2 rupees to 2-8; it is now never less than 5 rupees, and has been so high as 25 rupees per roo viss. An export duty of ro per cent is now charged on this oil. The Burmese Government also charge 3 per cent. Under the former system, it is stated that the charges, including the established douceurs to brokers, etc., were notless. In number, the wells were stated by the head-man of the village to be about 260 ; others said 100. ZAey certainly do not exceed in numbev 200. The well which yielded 400 viss per diem was shown to us as a remarkable one ; others were acknowledged to yield only 60 viss; and 1 think there was a general tendency іп our informants to swell the amount rather than diminish it. The average yield of the whole, therefore, must be much less than it was estimated to be by Mr. Crawfurd. Very careful inquiries convinced me that the average could not be morethan 180 viss from each well per diem. This would give (allowing that there may be 200 wells at work, which I consider beyond the truth) a total of 36,000 viss per day. If we take the working days at 300 in the year (which again is, I think, above the truth, considering the number of holy days, etc., in which a Burman revels), this would give a total pfoduce annually of 10,800,000 viss. Deducting from this 1-20th as an allowance for waste, breakage of gurrahs, loss of boats, etc., we should have 10,800,000— 540,000 = 10,260,000, 2.e., ten millions and one-quarter viss as the net available produce per annum. - * Another mode of arriving at the annual produce is to take the number of carts % employed daily in the conveying of the oil to the point of shipment, and multiply this by the average load of each. Now we could not ascertain that there were more than 150 carts so engaged, if so many. The average load of each of these IS 100 viss, and taking, as before, 300 days” work, we should have 100X150 X 300 only 4,500,000 viss annually, not one-half of what was stated to us. | “We have above calculated from the number of wells, as given by the Burmese themselves ; I am convinced, however, that the number given is above the fact. I could not see any reason to believe that in the larger group there were more than 80 and, inthe smaller or southern group more than 5o wells actually yielding petroleum ; the amount obtained from the wells of the southern group is also much less than that from the northern wells. It is also inferior in quality. In my view, either the produce has diminished most materially since Mr. Crawfurd's visit, or he very much over-estimated it from erroneous data, I fancy that both these causes have combined to render his estimate too high at present. “ These wells are, each singly, or a group of a few wells close together, the property of different individuals. In some cases they are a source of large and 6.69 ) 24 NOETLING: PETROLEUM IN BURMA. continuous profit; in others unsuccessful trials, which are not unfrequent, absorb all the profit, and even ruin the adventurer ; one of these pits costs from 1,500 to 1,800 Rs.—a large sum for such men to risk. Each family or individual has certain tolerably well-acknowledged limits, within which their rights of property are confined, but questions of boundary are a source of constant litigation ; the open- ing of a successful well close to the supposed boundary generally leading to a discussion of these limits, and to long and angry disputes." Dr. Oldham's description is less exhaustive than that of Yule; the chief point of interest is that he arrives at two widely different estimates of the annual production; his first estimate is decidedly too high, as he himself admits that the number of productive wells is certainly not higher than 130 in the aggregate. The statements about the twinzayo families are rather vague. : The chief interest of both these reports lies in the fact that both Yule and Oldham arrive at the conclusion that the number of pro- ductive wells in 1855 was certainly not higher than 130. I cannot trace any notes on the oil-fields in Upper Burma be- tween 1855 and 1873, when Captain (now Colone]) Strover submitted a highly interesting and valuable memorandum on the metals and minerals of Burma which was published in the Gazette of India} This is what Colonel Strover says about the oil-fields : “There are at present about 150 wells worked at Yenangyoung; the quantity of oil estimated as deliverable from these wells is 15,000 viss daily, of which 10,000 viss is taken by the contractor who supplies British Burma and 5,000 viss by the contractor who supplies Upper Burma. The yield of the wells is estimated yearly by officials sent down to Yenangyoung by His Majesty, and the Royal revenue is calculated at Rs. 7-8-0 per 100 viss and realizes four lakhs of rupees per annum. The total yield of these wells is 6,000,000 viss per annum or 9,375 tons. At Pagan there are about 50. wells: they yield daily 1,500 viss of oil, which | the earth-oil contractors, at present the Lay-myo-woon, and one Maung Tsanwah, are allowed to purchase, The total estimated output per annum is 6,600,000 viss to 10,3124 tons. ” Colonel Strover's distinct statements are the more valuable as they describe the condition of the oil-field just previous to a great rise in the number of wells. Pagan (ог the oil-field of Yenangyat) | is here mentioned for the first time. | 1 С. A. Strover. Memorandum on the metals and minerals of Upper Burma: Gazette of India Supplement (1873) 5 reprinted in Geol, Mag., 1st decade X, pp, 356—361 (1873). 49 4 HISTORICAL SUMMARY. 7%: 25 ` Dr. Friedlander visited the oil-fields in 1874, and his notes, “Тһе Country of Earth-oil in Upper Burma, ” were published in the Burma Gazette of the same year.! His description is very vague and does not come up to the mark of any of his predecessors. The only fact worth mentioning which he records is the existence of a rude pipe- line to convey the oil from the fields to the river. Dr, Friedlánder says: ** Worth mentioning here is also the oleiduct now in course of construction at Yenangchoung, and a decided improvement upon the old mode of transport by chatties in carts. Wholly made out of bamboo, supported by wood stages (the inside lacquered), it runs with a gentle slope from the wells down to the river bank : a great loss of oil by evaporation is inevitable." The existence of this pipe-line has been confirmed by the state- ments of several natives, but they all added that the loss by leakage was so great that they gaveit up at once. The earth-oil wells (of Yenangyoung) are situated on a plateau, says Dr. Friedlánder, five miles from the river near the village of Tóngong (Twingon). The number of wells are said to be 450. | At Pagan (namely, Yenangyat) there are 7o wells in working, most of them are new and they are adding daily others to their number ; the depth of the wells is from 60 to 8o feet. : The late Dr. Romanes, who visited the oil-fields of Yenangyoung - in 1884, reports as follows? :— * The oil-wells of Yenangyoung are situated on the banks of the creek that flows into the Irrawaddy at that place. There are two groups, the smaller about two miles east of the town, the other about three miles north-east. “The country is a tableland intersected by ravines, the beds of torrents flowing into the creek. The surface is covered with gravel and blocks of fossil wood. Below is a great thickness of a friable sandstone, below this again a blue shale alternating with beds of sand. It is in the sand that the oil is found. 7 Тһе wells are sunk indifferently on the sides of the ravines and on the tops of the hills. The strata appear to dip generally towards the west with many folds ut Dr. H. Friedlánder. The country of earth-oil in Upper Burma. Supplement to the British Burma Gazette, Feb. 14th, 1874, pp. 45—48. 2 R. Romanes, Report on the Yenanchoung Oil-Wells. Flsc. Pam. Rangoon, 1884. e m \ ` 26 NOETLING: PETROLEUM IN BURMA. and contortions, and the ravines run in a westerly direction. Hence a well at the head of a ravine, on the top of the hill, may reach the oil-bearing stratum as soon as one at the bottom. We saw a well being dug at the top of the hill. They had ` reached a depth of 135 feet. They were cutting through a hard blue shale full of - cracks filled up with «and. . The sand was wet with oil, but not enough to drain out. Another well, about 5o yards off in the ravine, was 250 feet deep. It was 40 years old, cil had been. reached at 160 feet, and it had been gradually deepened | to its present depth as the stratum of shale had been exhausted of oil. We saw some fragments of rock that had just been brought up. It was this same hard blue shale with cracks filled up with sand that we had seen at the other well. Go- ‚ing down the ravine I found a stratum of this oil-bearing rock cropping up, but apparently higher than that into which the wells were sunk. “This was the only well we saw at work, the others were stopped for the day. It gave 150 viss daily, and might give more were there means of carrying away the oil. The oil is raised in earthen pots shaped like a gourd holding about 8 to то. viss, from these it is decanted into larger pots of the same shape holding about 15 viss. Ten or twelveof these make a cartload estimated at 150 viss — about 5 cwt. The work of raising the oil was performed by a labourer and his wife, who were paid 8 annas per diem, 4 annas each. They work in connection with a carter who is paid Re. 1 for himself and a pair of bullocks making one trip a day to the river shore, whence the oil is carried in bulk in boats to the steamers. The capa- city of the boats is said to be about 25 tons of oil. * The method of raising the oilis very rude. Two forked branches set up- right carry a horizontal beam bearing a roller over which passes the rope. The labourer takes the end of the pedi and runs down hill with it and holds it while his companion runs down with another length, and so on. While the last length of rope is being drawn out, one of the men is waiting at the mouth of the pit to exchange the full pot for an empty one. * [t is impossible to say what the real maximum yield may be.. Many of the wells are not worked ; some of them are exhausted. We found that there were 130 cartloads brought from the great wells,! and this represented the accumulation of five days. Dr Oldham, thirty years ago, was told that the yield was 150 carts daily. If the wells are worked to their utmost now, unless Dr. Oldham was misinformed, the productiveness has greatly fallen off. * We were told that two wells had been sunk at à point to the south-west of the smaller wells on the other side of the watershed ; that oil had been obtained, but it was mixed with water, and the wells had been alwa ñq. I think it very probable that oil-bearing strata may be found all over that strange barren table land, of which Yenanchoung is the centre. “ The rock formation seems to be much more recent than that in which: we find the petroleum of Yenantaung in the Myanaung district and the coal of Ókpo. * | found many fragments of fossil bones but none perfect. The ferruginous concretions referred to by Dr. Oldham turn out on analysis to be principally oxide of manganese ; some calcaceous-looking nodules are carbonate of magnesium. “ The curious concretions which Dr. Oldham found on the shore are really cases of the roots of plants and of very recent formation, I found many in situ 1%2,, Twingon, F. N. S 72 y / HISTORICAL SUMMARY, | 27 t with the central vascular part of the root still remaining. Those on the shore have no doubt fallen from the top of the cliff as the river has washed it away. “ A fossil tree was found with the stumps of the roots and branches and the texture of the wood so well preserved that it seems possible to determine the nature of the wood. “Тһе present vegetation consists of acacias and euphorbias. A thorny shrub of the genus sisyphus is not uncommon ; it is used for fencing the cattle pastures. The only crop is maize. Jaggery made from palms is brought from the interior.” Information about the sale of oil during the period 1879 to 1881 1886 Burmese min- is contained in a letter dated the 22nd July me 1886 written by one of the late Burmese min- isters and addressed to the Chief Commissioner of Burma.! It con- tains interesting data about the number of wells, the production and the way in which the King of Burma disposed of the oil. As this letter is the only document relating to the above period, and as the statements are apparently reliable, I give here extracts from it :— * [t was customary to make over the oil obtained from the Royal wells as well as from those of the twinzas to the farmer of the year who paid a certain amount of royalty to the Government. The amount of such royalty was determined by an estimate prepared beforehand. Thus,from the year 1241 to 1243 (1879 to 1881) the following estimate was made :— Viss. Monthly yield = . e . А қ А ° А . 400,000 “ This was distributed in the following way :— | i Viss. Value in Rs. (a) For Royal purposes . . ; E қ : . 10,000 ? (4) Brought up the river at R25 рег 100 viss . А . 120,000 30,000 (c) Taken down the river at R15 per 100 viss . €. 4 = 270,000 40,500 Total. . 400,000 70,500 “The total of proceeds were therefore estimated at R70,000 per month, “Тһе actual expenditure was :— R . (a) Paid to twinzas for the oil at R1-8-0 per roo viss 4 e. * « 6,000 (6) On account of boat-hire R2-8-o per 100 viss š - : e 10,000 Total . 16,000 1 I Total of proceeds Қ 5 4 F x 5 e š . 70,000 П Total of expenditure . e i À ° : ni. ^x . 16,000 Balance „ 54,000 1Dr. Fritz Noetling. Report on the Petroleum industry in Upper Burma from the end of the last century up to the beginning of 1891, pp. 14-15, Rangoon, 1892. š | c > ] 28 NOETLING: PETROLEUM IN BURMA. “Thus the farmer paid a monthly royalty of R50,000 during these years, Since 1243 (1881) the demand for earth-oil was diminished and the whole of the yield could not be bought up. The estimate was :— Viss. (a) For Royal purposes . . . "ot ds ° . e 10,000 (ó) Brought up the river > ° » ° ° ° а . 90,000 Brought down the river . Е “ e А А ° . 160,000 Total . 260,000 * Proceeds of sale R34,700. * Made up of R23,400 value of the oil brought up and sold at R26 per 100 viss plus R11,200, the value of the oil taken down and sold at R7 per 100 viss. * Expenditure— x (а) Paid for the oil Kr-8-o per тоо viss . ° ° А ° . 3,900 (6) Boat-hire at R2 per 100 viss ө š š 2 Е i - 5,200 Total e 0,100 I Total of proceeds о И. А Б E . а . 34,700 II Total of expenditure. к > . . - : š e 9,100 Balance • 25,600 “ Thus the farmer paid to the Government R2,5oo as a monthly royalty. Sub- sequently, in May 1885, the royalty was reduced to R20,000. The twinzas were exempted from the thathameda or capitation-tax on account of their services rendered to the Government." The following table was appended to the letter :— YENANGYOUNG. PAGAN. TOTAL. > > > — سم‎ — d = E^] 8 4 ==: u Eu - Š . "o . E . "d . 5 — u n n n n И 22. El 2 PE] 8% Je] = E ша ESLE ` D Ф g > чы чә Ф б> чы 5 O d? P LES Кс Ë = Өз п> Ев n! К ыу [© Eg Ф 5 чә “he ... - "y чә. en = us чә “he © onas S dd sen tae DEI e 1194 9 = g€ - "UO = Ç ы "y = о = = wo AS 6.4 Ej 2] 8 ars Е| als e. EJ Re Lis Qm ST E qu an” ze E s = an ЕЕ ғ Ар 13:4) t 2121461 0 Royal wells E |138 | 72 | 66 | 26,000| 38 | 23 | їз | 8,000 |176 | 95 | 81 | 34,000 Wells belonging to |198 |... |108 |360,000| *| *| * | 2,000 |198 |... |198 | 362,000 twinzas, ToTAL ‚ 1336 | 72 |264 | 386,000 | 38 | 23 | 15 | 10,000 [374 | 95 |279 | 396,000 * Number not stated, (7) «тты т A . t Los Ser H ert n J ^ Mi Б ? HISTORICAL SUMMARY. | 29 CHAPTER IIL.—THE OCCURRENCE OF PETROLEUM IN THE DISTRICTS OF PROME AND THAYETMYO. Although not quite falling within the scope of this memoir, it will be useful, for the sake of completeness, to mention the occurrences of petroleum in the above districts, I paid a flying visit to Padouk-bin and Banbyin early in the rainy season of 1892, but partly on account of the rains, partly on account of the dense jungle, I was not able to see much for myself, and, as my time was limited, I could not examine the geological features of these localities as well as of others, I follow, therefore, chiefly Mr. Theobald’s description,’ adding remarks ог observations of my own, I.—GEOGRAPHICAL POSITION. Mr. Theobald mentions the following localities :— 1. Yenandoung, 12 miles south-west of Myanoung, Lat, 18?9', Long. 95? 12.’ 2, Padouk-bin, Lat. 19°21’, Long. 95 11^, about seven miles west by north from Thayetmyo, 3. Banbyin, Lat, 19°21’ Long. 05710. about 11 miles west-north-west of Thayetmyo. 4. Toungboji, about 113 miles west from Prome Pagoda, about Lat. 18°20’, Long. 954. | As already noticed by Mr. Theobald, all these localities are situated on the western bank of the lrawadi river, and he mentions no . occurrences of petroleum within the area of the Pegu Yoma, that is _to say, on the eastern side of the Irawadi. КУ 2.—GEOLOGICAL FEATURES. Мг. Theobald states that all the localities are situated among the nummulitic rocks or the still newer tertiaries. I am unable to verify this statement with regard to the rst and 4th locality, but as regards Padouk-bin and Banbyin, I can say, from personal experience, that the series there developed must be considered to belong to the Pegu division. Mr. Theobald states that at Padouk-bin the rocks are “ soft, earthy bluish sandstones and shales of the newer tertiaries.” From this we may conclude that he does not consider them as eocene, 1 Mem. Geol. Surv. Ind., X, 346. ( 75 ) —- Fp . 46 NOETLING : PETROLEUM IN BURMA. With regard to the second locality, Mr. Theobald is a little more explicit, stating tbat “ the country consists of beds of shale and sand- stone, occupying a high position in the newer tertiary group, and probably not far removed geologically from the horizon of the bed at Padouk-bin." | From this we may conclude that Mr, Theobald opines, that the petroliferous beds of both localities belong to his Pegu group, holding a high position in the series. Mr, Theobald concludes his remarks about the Banbyin oil locality by stating that the shales contain certain fossils of the ordinary Miocene types : Ostrea, Pecten (2 species), Conus, Cyprea, Arca, Solen, Turtlella, crab’s claws, shark's teeth, etc. I have unfortunately not found any fossils myself at the last-named place, nor have I succeeded in finding the above-named fossils ` among Mr. Theobald's collections from Lower Burma, but I have no doubt that the species will agree with those described by me from Minbu or Yenangyat, This view, together with Mr, Theobald's statement that the petroliferous beds hold a “ high position” in the series, prove that the geological horizon of these beds must be nearly the same as that of the petroliferous sands of Upper Burma, vzz., the upper part of the lower miocene or Prome stage. With regard to the 4th locality, of which 1 have no personal experience, Mr. Theobald simply states that it is situated within the area of the Nummulitic rocks, without giving any further evidence for his statement. It is à 277077 not impossible that petroleum should occur in the eocene rocks, but so far it has everywhere in Upper Burma been found in beds of miocene age. : Before, therefore, accepting the eocene age ofthe Toung-boji petroleum, I think the matter requires further confirmation. . | . Asregards the first locality near Myanoung, the description of the strata proves clearly that they belong to Mr. Theobald's Pegu group ; in other words, that they are of miocene age. DEB ) 5% | PROME AND THAYETMYO. | 31 3.—STRATIGRAPHICAL FEATURES. Little or nothing is known about the structural conditions under which the petroleum occurs; Mr. Theobald simply states that the strata are “rolling and dipping at various angles,” but the diagram he gives of the occurrence of petroleum at Padouk-bin clearly proves that _ it occurs on the crest of an unsymmetrical anticline. As far as I am able to judge, both occurrences of Padouk-bin as well as Banbyin are situated on an anticline running north-west to south-east. With regard to the other two localities, I am unable to say any- thing definite, but further researches will probably prove that they are situated on anticlinal arches. 4.—ECONOMIC VALUE. The above-named localities have hitherto not given rise to any industrial undertaking ; even the natives after some attempts have entirely abandoned their wells, which atthe time when I visited these localities were in a very dilapidated condition. The Burma Oil Company had several deep wells drilled at Padouk- bin before they commenced to boreat Yenangyoung. Unfortunately there were no boring registers kept, or if there were any, they have been lost, As far as I could ascertain the wells reached a consider- able depth, but no petroleum was found, and the Company eventually abandoned this particular spot as unprofitable. Although it might be rash to entirely condemn the occurrences of petroleum in Lower Burma as insignificant, when nothing more is obtainable than such meagre information, my personal opinion is that it is very unlikely that these small occurrences indicate a larger quantity of petroleum in greater depths. This much has been proved by the deep borings at Padouk-bin. It may be that, when the indica. tions are followed up, richer oilsands will be discovered, but it seems questionable whether they would be worth the large expenditure incurred. | (277. у) 32 NOETLING : PETROLEUM IN BURMA, CHAPTER ІП.--ТНЕ OCCURRENCE OF PETROLEUM NEAR MINBU. 1.— GEOGRAPHICAL POSITION AND PHYSICAL GEOGRAPHY. The village of Minbu is situated at Lat. 20%10”, Long. 94°56’ on the right bank ofthe Irawadi about 423 miles above Rangoon, at the northern end of a low hill range. The vast alluvial plain of the | Mon river extends to north of Minbu ; to the south and west of it is alow hilly country, which comes right up to the bank of the river. Petroleum has been found at different places in the neighbourhood of ` Minbu, and there are indications at the southern slope of Leit-taung that petroleum was formerly gathered in shallow pits, These are now entirely abandoned and dried up. The next place where petroleum oozes out on the surface is around the Nagabwet-taung or mud volcanoes, on the northern bank of the Sabwet-choung, a small feeder of the Irawadi river, About five miles in a straight line, further the south, in a small stream between the villages of Palangon and Nandawgon is a third ` locality where there are some surface indications. But nowhere has an attempt been made to extract the oil from the deeper beds, although the petroleum was gathered to a. small extent from the surface of natural springs. Itis difficult to say why the Burmans, who have followed up the surface indications at Yenang- young and Yenangyat, have never attempted to exploit the petrolifer- ous beds of Minbu, 2.—GEOLOGICAL FEATURES. | A—The Pliocene or Irawadi series. Lithological and paleontological characters. | This division consists chiefly of yellowish sandstones of various degrees of hardness, with subordinate coarse conglomerates, which are always more or less ferruginous ; globular or flat concretions of hard, quartzitic sandstone are common. [15 л MINBU. | 33 As regards the palaontological characters I am unable to say more than a few words, because fossils are somewhat rather rare in the neighbourhood of Minbu ; I have found numerous fragments of bones, belonging probably to the same species of Triomyx which is so common near Yenangyoung, imbedded in the conglomeratic beds along the bank of the river, but they were too ill-preserved to be specifically determinated, No attempt has been made to sub-divide this series, which consists of certainly not less than 5,000 feet of sandstones, alternating with conglomeratic or occasionally argillaceous beds. The monotonous character of these beds, together with the scarcity of fossils, render sub-division extremely difficult. In addition to this the country is covered with a low but dense jungle which effectually hides all struc- tural details, | B.—The Miocene or Pegu series. While the pliocene almost completely composes the country around Minbu the miocene crops out only within a small area along the axis of the anticlinal arch. It is questionable whether the entire sequence of the Burma miocene, namely, both the Yenangyoung and the Prome stages are superficialy seen. It is certain that the Yenangyoung stage exists, but it seems doubtful whether the - Prome beds come to the surface, whereas they are unquestionably ` developed in greater depth. | | Lithological and palzontological characters. The strata of this series consist chiefly of olive coloured or bluish clays and olive coloured rather soft sandstones, the latter frequently contain layers of elongated sandstone concretions. ` The Yenangyoung beds have yielded a good collection of fossils which I have described in a separate memoir. As the geological position of this fauna has been discussed in detail elsewhere? it would be superfluous to repeat my views, so recently expressed, Y Supra, pp. 1-45. ? The development and sub-division of the Tertiary system in Burma. Records of the Geol. Sur. of India, 1895, Vol. XXVIII, p. 59. D CU, 9 '34 NOETLING : PETROLEUM IN BURMA. and it will be sufficient to say that the composition of the fauna is somewhat different from that of Singu and Yenangyat, and that it holds most probably an intermediate position between those two 7 faunas. 3.—STRATIGRAPHICAL FEATURES. Any section from the river bank towards west at once demon- | strates that the strata form a rather high, but unsymmetrical, anticlinal arch, the sides of which are formed by the beds of the Irawadi series, while in its centre the Pegu series is exposed. | Along the river bank the beds dip vertically, and in some places are even reversed; the vertical dip continues along a distance of approximately 1,000 feet to the west from the river bank, that is to say, the hill range running immediately along the river bank is throughout composed of the steeply inclined beds of the Yenang- young stage and lrawadi series. Towards west the dip gradually lessens, and within a distance of about 600 feet from the western foot of the hill range the strata dip at an angle of about 15? towards east. Unfortunately the gradual change in the inclination of the beds can- ` not be observed because a valley filled with débris intervenes. The dip lessens gradually till finally the beds are seen to be perfectly horizontal in the low ridge closing the valley in which the mud volcanoes are situated towards north; from this point the strata dip rather quickly toward west, but the angle of about 12? to 15? is very constant and does not increase as far as I have traced them towards west. : Judging from this structure, the strata form here a true fold, on the top of which the mud volcanoes and natural oil springs are situated. Iam unable to say how far south this anticlinal arch extends; towards north it seems to come to an end within a few miles of Minbu, where the alluvial plain of the Mon river butts immediately on the tertiary rocks; but I am unable to say whether the latter dip normally below the alluvial deposits, or whether a cross fault has cut off the anticlinal. ( 8о ) P "M ( : | Towards south the anticlinal has been traced to about ten miles south of Minbu, beyond which I have not followed it, Along the anticlinal petroleum oozes out from the surface at several localities, but the principal place, where there are the most numerous indications, is immediately west of the European quarters of Minbu, in a valley in which are situated the famous mud volcanoes of Minbu, described in the following section. — 4.—THE Мир VOLCANOES. Although the Nagabwet taung of Minbu have been a source of great wonder to the natives for ages past, they are hardly mentioned in the earlier descriptions of Burma. The reason for this is that Minbu was seldom visited by travellers, being somewhat off the | general route taken by the boats which ply on the Irawadi. | | Dr. Oldham was the first to give an account of them, but | being pressed for time he could not go into details, Accord- | ing to his description the cones must have been much lower in | 1855 than they are now, as their height is stated to be between 12 x and 15 feet, Unfortunately Dr. Oldham has not stated how many cones existed at the time of his visit; it would have been of great interest to know whether the number of those mud wells, which rise on the top of cones, has changed during the last 40 years. It is however quite evident that at the time of Dr. Oldham's visit there - existed the two groups, here described as the southern and northern group, which differ as regards physical aspects. The most . remarkable fact of Dr. Oldham's observations is his statement of the temperature which he gives at 87? F., this is decidedly higher than has been observed by me in any of the mud wells except one. I may mention here that Dr. Oldham visited Minbu at the end of October, that is to say, just before the beginning of the cold season. 1.—Situation of the mud volcanoes. They are situated about 3,000 feet west of the civil station of Minbu, in a narrow valley running north and south, which joins the Sabwet-choung to the south; the northern end forms a kind of D 2 CAF) 36 NOETLING: PETROLEUM IN BURMA, elliptical amphitheatre. Having visited Minbuat different times, in February 1888, May 1889 and March 1895, I am able to record | the changes which each of these mud volcanoes have undergone during the last seven years, In describing them, I will begin with the southern one, and proceeding towards north will describe a number of wells in convenient groups. 2,—Detailed description: A. Southern group. Under the term southern group l include all mud volcanoes which are situated west of the Sekkate Pagoda, close to the northern bank of the Sabwet-choung; they extend over an area of about 1,100 feet in length and about 250 feet in breadth. | No, 1r.— This, the southernmost mud volcano, is situated on a very low cone, with gentle slopes. In 1888 and 1889 there existed simply an irregular eiliptical, shallow basin filled with water, in which a few gas bubbles rose occasionally. To all appearance it seemed to be extinct. In March 1895 I found it exceedingly active. Its former ground plan of an irregular basin of a diameter of about 4' x 5' was still retained, but this was filled with liquid mud, the surface of which remained a few inches below the rim. Small gas bubbles, rose slowly and at irregular intervals ; when a particular strong outburst took place, it threw tbe mud noisily over the rim, A strong smell of petroleum was noticed and the mud was covered with a streaky black film. Temperature of the mud 84? F. No. 2.—' This mud volcano forms a very low cone with gently inclined slopes, on the flat top of which are the chief vents, while on the sides there are numerous parasitic cones, In February 1888 ] observed eight chief vents, which were all very active, ejecting a watery mud. The gas bubbles rose slowlier in some of them than in others ; the temperatures observed were— 80? F. So” F. 75 Е. 82? F. 77 F. 76° Е, » = 82° Е, " ~ 75 Е. a vent RU Aa o р лау MINBU. | | 37 In 1889 the general shape had not altered; there were still eight vents visible, of which, however, опе on the top of a low parasitic cone, had ceased to be active, while a second one ejected gas only, which came out with Hissing noise without being accompanied by mud. The northern vent was the most active; it formed a crater- like basin filled with muddy water, which seemed to be in a state of boiling caused by the incessant rise of gas bubbles. Five feet to the west of this was another, and 15 feet south of the first a third vent. These three vents were all situated inside a low crater filled with mud in a more or less liquid state. Of the smaller ones, a low cone, which was very active in the previous year, had ceased to be active, the others were small holes filled with watery mud in which gas bubbles rose. | | In March 1895 there were, besides a number of smaller, seven chief vents, one of which, the low cone already mentioned, was not active. The others were all more or less active, and produced in one case a considerable stream of mud. Beginning in the south, vent (2) is represented merely by an opening out of which flows a stream of very liquid mud. The opening itself is marked by the incessant rise‘ of gas bubbles; the temperature of the mud was 84? F. Next to this, about t0 feet west, were a series of small holes, filled with very liquid mud, one of which was very active, incessantly ` _ throwing up gas bubbles; the temperature of the mud was 79? F., whilst in another case it was 78? F. (c) About 30 feet north of (2) there were a series of small vents arranged in a line running in easterly direction towards (g), the extinguished cone. None of these vents were very active. A small stream of very viscous mud was flowing out from the largest vent (c) ; gas bubbles were rare. | (4) About 7 feet north of (c) there was a hole which was exceed- ingly active. A large stream of watery mud flowed out of it, and the position of the hole was marked by the permanent rise of large gas bubbles, which sometimes threw the mud some distance up, but without forming a crater or cone. The temperature was 85? F. ( 83.) 38 NOETLING: PETROLEUM IN BURMA, (e) About 24 feet east of (d) was a crater-like circular basin, filled to the rim with very liquid mud, which slowly flowed over; gas bubbles were rising continuously. The temperature of the mud was 78° F. . P. (f) Five feet east of (e) was a small hole filled with very viscous mud at 80° F., in which small gas bubbles rose slowly. (g) South of it, and in the continuation of the line of vents (c), | was a small cone about 3 feet high, built up of flakes of mud which spurted out from the vent. It was entirely extinct and at the time surrounded by more recent streams of mud. The smell of petroleum was strong everywhere, and the mud was covered with a black film. From the above description it is clear that mud volcano No. 2 has retained its low conical shape during the last seven years. It also seems as if the number of main vents remained the same, but I am certain that their position has shifted, although I am unable to say to what extent and in what direction. The nature of the mud thrown out has not changed since r888, and although there are traces of a cone, the force was apparently insufficient to eject it to any distance. In 1888 the temperature of. the mud varied from 75° Е, to 82° F. ; in 1895 the lowest temperature recorded was 78°, while the highest was 84^ F. All the vents seemed to work independently, although it . must be noticed that when No. 1 had its paroxysms, No. 2 simul- taneously spurted out large gas bubbles. No. 3.—With this a group of mud volcanoes begins, which have all thrown. up cones; No. 3 is a double cone, that is to say, on a common basis of about roo feet in length, rise two cones to about 3o feet above the ground, separated from each other by a saddle of about 25 feet.in width. In 1888 No. 3 (a) was very active, there were three vents, out of which flowed a small stream of viscous mud; the temperatures recorded were 69°, 75°, 77° E. E In 1889 there existed only one vent at the top of the cone, having a diameter of about half a foot. The mud did not rise to the rim, but remained. about. 5 feet below it, in a sort of narrow funnel ; occa- sionally gas bubbles rose with some force, by which flakes of very TK H4. ) MINBU. | 39 viscous mud were thrown over the rim. In 1895 the general shape of the cone had not changed in any way, but on its top there was a crater of about five feet in diameter filled with a very viscous mud which slowly flowed off through a break on the eastern rim of the crater. The temperature of the mud was 82? F. 3(0) To the west of No. 3 (a), rises a blunt cone No. 3 (4), which has not been active since 1888 ; its sides are much denuded by rain water, which has eroded deep furrows in it. On its west side, close to the base is a small vent, hardly a few inches in diameter, which is filled with liquid mud. 3(c) On the southern side of 3 (a), close to the base, is a parasitic cone of about 6 feet in height with very steep slopes. In 1888 and 1889 there was a small crater at the top filled with muddy water, which was slowly flowing off. In 1895 it had entirely ceased to act. From the above description it will be seen that the general shape of No. 3 cone had not altered. It is, however, quite certain that the vent of No. 3 (2) has undergone several changes, that it was com- paratively active in 1888 ; in 1889 the activity had decreased, while in 1895 it begun with renewed vigour. Vent 3 (2) showed no signs of a change, while No. 3 (c) had become entirely extinct. The tem- perature also exhibits some changes; in 1888 it was between 69? and 77° while in 1895 it was at the same vent 82? F. No. 4,—A high cone rising about 40 feet, north of No. 3 (a). Like the former, it consists of a gently inclined base on which rises | rather suddenly a cone with very steep sides. In 1888 it hardly exhibited any signs of activity ; there was a small vent on the top, out of which flowed a narrow stream of mud with a temperature of 75°F. In 1889 it had resumed its activity ; on the top was a crater of about a foot and a half in diameter filled with a very viscous mud, which rose to the rim of the crater, gas bubbles were frequent and large, ` and after a very heavy outburst the mud ran over the rim. In 1895 the cone had again relapsed into inactivity, but at its northern base where it seemed to have been traversed by some deep fissures very (С “Эр! ADN NOETLING : PETROLEUM IN BURMA viscous mud spurted out periodically from a small hole, and with. such force, that it was thrown up in the air. A stream of mud apparently issued from this vent, whose exact position could not be traced owing to its being hidden below mud. Another parasitie cone at the northern end was dry. The general shape of this cone has not changed, but its activity exhibited great variations. From being nearly extinct in 1888 it rose to a state of comparative activity in 1895, but since that time it has quieted down considerably. No. 5.—This is the most remarkable of all the mud volcanoes near Minbu; it is the largest and highest amongst them and is at the same time the most active. It has undergone various changes since 1888 ; measured from the northern foot of No, 4 it is about 300 feet to the north of that cone, and rises in a rather steep cone of about 40 to 45 feet in height on a very gently inclined and broad basis. In 1888 it formed a single cone with a crater of about 6 feet in diameter, which was filled with a very viscous mud in which rose enormous bubbles of an inflammable gas with a strong petroliferous odour. The rise of the gas bubbles produced a gurgling noise, then the surface of the mud slowly rose in a huge bubble which fell back on bursting, producing a kind of concentrically rippled surface on the mud which fills the crater. The temperature was 76? F. To the south-east were two smaller vents with watery mud at the same temperature, In 1889 the same vent was as active as before. 1 noticed, how- “ever, a remarkable occurrence ; within 24 hours the level of the mud which filled the crater rose by about 6 inches. The first day when I visited it, the surface ofthe mud was about 6 inches below the rim of ` the crater; on the second day it had risen and filled the crater to the rim ; active. In 1895 the smaller vents had combined and formed a second main crater towards south-east, separated from the older crater by a low saddle in which there was a third vent (See plate III), The new ( 86 ) the smaller vents, on the south-eastern side were very (oS 7» 20444 ПОА. л. Dus ОТЫ 27 > 1 "LAT т УГУ í `A MINBU, 41 or southern vent, 5a, formed a circular crater of about 5 feet in dia- meter, in which the mud did not quite rise up to the rim, but remained about 5 inches below it. It flowed off through a small break at the western side. Gas bubbles were large and frequent. The temperature was 78? F, The northern or older vent 5% formed a crater of about three and a-half feet in diameter, filled to the rim with very viscous mud, in which small gas bubbles rose. At long intervals a stronger eruption took place, when the mud overflowed ; the temperature was 78° Е, Between the two was a third vent, 5c, of about afoot and a-half in diameter filled with very liquid mud, which did not reach up to the rim ; gas bubbles rose, but not frequently ; the temperature was 75? F, From the above description we see that this mud volcano under- went great changes with regard to its shape; from being a single vented cone in 1888 it changed to a double cone in 1895. No. 6.—Rather less than 200 feet north of the former the last of the cone rises to a height of about 35 feet. In its general shape it resembles the No. 32 ; in 1888 it was only feebly active. There were two vents on the top, from which a small stream of mud flowed with a temperature of 75? F. The same two vents were seen in 1889; the northern being the smaller of the two. There was no stream of mud · flowing, but occasional flakes of mud were thrown out of the vents. In 1895 there was only one vent at the top, of about 6 inches in diameter, filled with a very viscous mud which did not reach the rim, Occasionally gas bubbles rose, spurting out small flakes of mud. The temperature of the mud was 75? F. A small vent at the northern foot contained very liquid mud of 78? F. The mud volcano has not suffered any changes in its general shape since 1888, although it is quite certain that the vents have shifted. | No. 7.—This is an irregular basin filled with muddy water up to about 2 feet below the rim, west of No. 4, but not strictly speaking, belonging to the group Nos. 3 to 5, its physical appearance being more relatedto Nos. 1 and 2. Gas bubbles are | ( 87 ) 42 NOETLING : PETROLEUM IN BURMA. frequent and the water is covered with a thin film. of petroleum, The temperature is 76? F. Itis remarkable that while mud volcano No. 5 underwent such considerable changes since 1888, this one has not changed in the slightest degree since that year, notwithstanding there being a continuous rise of gas bubbles. The crater-like basin, partly. filled with water in which bubbles rise, was the same in 1888 as in 1895. Besides these active mud volcanoes there are the remains of at least two extinct ones, which must once have possessed cones of considerable height, but are now almost entirely denuded by rain, leaving only their base still visible. One of them (A) is close to the southern base of No, 3, shown on plate I; the second one ( B) is east of No. 2; it is not represented on any of the plates. B.— Middle group. About 700 feet north of the group mentioned above there are a few. smaller mud holes, one of which is particularly active. It forms a crater like basin of about 7 feet in diameter, which is filled with muddy water in which gas bubbles rise incessantly ; the mud has a temperature of 82? F, and is covered with a thick continuous brown film of petroleum. Besides this there are a few small cones, around which the ground is saturated with petroleum, None of them were active, and only one emitted gas with a hissing noise. No changes have been recorded since 1888. C.—Northern group. About 1,300 feet north of No. 6 there is another group of vents which, although very active, scarcely deserve the name of mud volcanoes. These wells are all more or less irregular basins which are filled with a watery mud, in which small but numerous gas bubbles riseincessantly. The surface of the water is always covered with a ` thick film of petroleum. The largest of these holes forms an irregular dm of about ( 88 ) | 5 К. B .. | | 4 E n p M EM MINBU. | 43 50 X 20 feet, filled with a watery mud of about 82? F. Inside this basin there are numerous independent vents, which emit gas continuously, some of them with a hissing noise; the surface of the mud was covered with a thick film of petroleum. The principal basin is surrounded by numerous vents, some of which emit gas only, while others eject a very viscous mud, mixed. with petroleum. The tem- perature varied from 79? F. to 82° F. Several vents of this same kind are found a short distance north of this one; in all cases a more or less circular basin is filled with a watery mud in which numerous gas bubbles rise. The northern- most of these holes, just at the foot of the hill, is remarkable for its comparatively high temperature, which was repeatedly measured and found to be 97°. І first attributed it to the heating influence of the sun, but after having found the same temperature early in the morn- ing, before sunrise, it must be considered as the actual tempera- ture of this mud well. 3.— General features. So far it appears that the mud volcanoes have little in common in general shape, but we shall eventually see that the basin shaped mud wells and the conical mud volcanoes are only modifications of one and the same phenomenon. | The features in common are : they all produce a greyish blue mud, of varying consistency, more or less saturated with petroleum, and emitting an inflammable gas in smaller or greater quantities. It appears unquestionable that the mud volcanoes of Minbu are more or less intimately connected with subterraneous petroliferous strata, and their position on the west of the anticlinal arch is therefore by no means accidental. The mud brought up by the mud volcanoes resembles in fact so much the débris baled out of the drilled wells at Kodoung, that samples of both cannot be distinguished, — The source from which the mud and gas rises cannot possibly be very deep below the surface ; thisis indicated by the low temperature of the ejected mud. Except one well in the northern group, . which ( 89 ) 44 NOETLING : PETROLEUM IN BURMA. has a temperature of 97? F., the temperature is never higher than 85°, but even this and the next lower temperature, 84°, are not com- mon; the bulk of the wells possess a temperature between 75? F. and 82? F., that is to say the temperature is much lower than that recorded in any of the pit wells of the Yenangyoung oil field. It is therefore beyond doubt that the source of the mud volcanoes must be close to the surface, The fact must also not be overlooked, that often wells which are close to each other differ in temperature, though not greatlv. Much more important appears to me the probability that, owing to the superficial position of the beds from which the mud and gas is derived, the temperature changes with the season. This hypothesis could easily be confirmed by a series of observations extending over a few years. | If the change of the temperature with the season cannot be abso- lutely proved, for the present it is quite certain that the activity of the mud wells changes with the season, or more accurately with the level of the river. When the river is high, the mud volcanoes are very active, when it is low, they subside into a comparative state of rest. I first visited the mud volcanoes in February 1888 when they were at a comparative state of rest, but in June 1888 when revisited. Minbu they were all very active. Тһе same applies to my visit in May 1889, when they were all more or less active, while in March 1895, they were generally speaking less active. It seems to me no mere accident that a greater activity should coincide with the high level of the river during the rains or a state of comparative rest with that of a low level during the dry season. Having already mentioned that the source of the ejected mud cannot possibly be very deep, it is probable that the change in the level of the ground water, which must happen with the rise and fall of the river, influences the activity of the mud volcanoes. ( 9° ) - | MINBU. | 45 With regard to the general shape of the mud volcanoes we may distinguish two types, 222. :-- (a) Basins. (5) Cones, In their extremes the two types are well distinguished, and no . greater contrast could be imagined than that which exists between mud volcano No. 5 (see plates III and IV) and one of the wells in the northern group, but No. 1 of the southern group proves dis- tinctly that these are simply different effects of one and the same cause, an explanation of which will be given presently. (а) Basins.—The basins are more or less circular or elliptical holes formed in the ground. When dry it may be seen that their walls are steep and the bottom rounded. When in activity the basins are filled with muddy water, which generally forms a sediment; from the bottom rise incessantly numerous small gas bubbles which give the liquid the appearence of boiling. Some of the vents seem rather constant, as indicated by the rise of the gas bubbles; others are only temporary; the gas rises for some time at a certain spot, the vent becomes clogged and fresh gas bubbles rise at another place. Petroleum is brought up with the gas and forms a more or less continuous film on the surface of the water. | | Although most of the basins are permanently in a state of activi- ty, they never produce mud streams of any extent. This applies particularly to the northern group. The general shape of the great well No. 1 has not altered since 1888, nor has that of any of the other wells, for instance, No. 7 of the southern group. (5) Cones.—Thé cones are built up of mud streams, generally with very steep sides, as may be gathered from any of the plates, illustrating them, We may assume, that before the steep upper cone ` was finished, the vent was situated on a low flat cone such as is represented mud volcano No, 1. The conditions for theraising of a cone seem to be the presence of a great mass of viscous mud ( 91 ) 46 NOETLING: PETROLEUM IN BURMA. combined with certain amount of gas pressure. In this case the mud is ejected in flakes, which are thrown up high in the air and fall luck with a splashing noise around the vent. If the action goes on for some timea cone is raised, whose surface shows the same flaky structure as noticed in the fumaroles of a lava stream, and on the top of which is a crater-like basin filled with mud, through which the gas rises. Secondary vents frequently appear on the sides of the cone, . and they may in time become more important, eventually assuming the position of a chief vent, This is beautifully illustrated by mud volcano No. 5. Itis obvious that with the rise of the cone, the mouth of the vent, which ejects the mud, rises above the surface, and a certain pressure is required to overcome the weight of the mud in the vent, It does not seem, however, that the gas pressure is any- thing very large, because a height of 40 feet from the surface to the summit of the cone seems to be sufficient to counteract the explosive force of the gas, which then only slowly rises in bubbles through the mud. The cones generally produce streams of mud of smaller or greater viscosity, When the mud in thecrater has risen to the rim, an overflow takes place, and the mud runs down the sides of the cone, quickly at the upper part, where the sides are steep, and more slowly on the base, where the gradient of the slope is very small. The first part of a mud stream generally dries up very quickly, but still retaining some moisture, it forms a pavement on which the subsequently ejected masses flow, without their movement being too much slackened by the loss of moisture at their lower side. When ` the activity of the mud volcano continues, the spasmodic gas eruptions produce many spasmodic overflows of the mud in the crater, The ejected mud, flowing for some time in the same direction down the slope, forms, in consequence of the loss of moisture along its sides, a narrow channel with raised sides (see plates V, VI, and VIl) inside which the later ejected mud runs down rapidly, till its movement is arrested along the lesser slope near the ( 92 ) СӘ» IU p 'MINBU. | 47 ‘base of the cone. Now the stream begins to spread out; the - walls of the channel gradually diverge (plate VI), driven aside by the pressure of the fresh masses, but still they continue almost to the end of the stream. Inside the walls the mud flows with lesser and lesser speed, partly on account of the small gradient, partly on account of the loss of moisture, and as new masses press on from above, the partly solidified mud cannot move forward, it is therefore raised and shaped into folds which produce a curiously wrinkled surface (plate VI). The wrinkles run transversally across tbe stream, and more advanced in the centre than at the The end of the mud stream, where the loss of moisture is rather rapid, shows a curious rugged structure, resembling very much that of the front of a lava stream. The central part of the mud stream, which looses its moisture less rapidly and dries more slowly, is therefore in a dried state intersected by numerous longitudinal cracks (see plate VI). The plates V to VII illustrate these streams; on plate V is figured the top part of mud volcano No. 5 as it appeared in May 1889; the narrow channel with its raised edges is extremely well seen, Plate VI illustrates the lower end of the same stream as seen from above, the diverging of the side walls, the sigmoidal wrinkles on the centre of the stream, as well as the longitudinal cracks in old dried up streams are well exhibited. Plate VII exhibits the lower part of a mud stream running from the right to the left. Origin of the mud volcanoes.—The question why these mud volcanoes should have formed near Minbu only, and not at other loca- lities, such as Yenangyoung or Yenangyat, is a difficult one to answer if we consider that at the two last named localities the same conditions prevail as at Minbu. At Yenangyoung, but particularly at Yenang- yat, thereis a high pressure of gas sufficient to produce flowing wells. At both localities. the drill has proved that there exist thick layers of clay, and that there is an ample supply of water, in fact ( 93 ) 48 | NOETLING : PETROLEUM IN BURMA. everything required for the existence of mud volcanoes, yet there is not the slightest trace of them at either locality, From this it seems quite clear that some other conditions must prevail which cause mud volcanoes, and that clay, gas and water are not by them- selves sufficient to produce them. | | The examination of the country around suggested, however, an idea which may afford some sort of an explanation, I have pointed out that the mud volcanoes are situated in an elon- gated horseshoe shaped valley, filled with recent argillaceous beds, It is probable that this horseshoe shaped valley has been caused through subsidence of part of the miocene strata below; at least the appearance of the northern, eastern and western side seem to support such a view, though it is possible that it is only a valley of erosion. The question of the nature of this valley is, however, only of secondary importance ; the fact remains that here is a basin of tertiary strata covered by recent alluvial beds. I believe the petro- leum and gas rose along fissures in the tertiary beds below, and were arrested by the impermeable layer of alluvial clay which covers the tertiary beds as stated, so that when the pressure of gas and petroleum collected immediately under this covering layer, had acquired sufficient force to break through the superimposed alluvium, it formed a mud volcano. In the other cases the pressure may have been gradually relieved through existing fissures, As it is more than probable that the alluvial clay rests on strata charged fully by ground water, the above hypothesis would explain— (a) The low temperature of the mud ejected by the mud vol- canoes, (0) Their periodical change of the activity. The following diagram woodcut, fig. r, will illustrate this view, but I must mention that I do not insist on this explanation being | applicable to mud volcanoes elsewhere. Unfortunately I have not seen yet the large mud volcanoes of ` Ramri and Cheduba island on the Arrakan coast, and I cannot there- fore say in what relation they stand to the mud holes of Minbu, ( 94 ) MINBU. DEM 49 Mr. Mallet's otherwise so exhaustive paper! does not say whether the mud volcanoes of these islands are directly built up on tertiary beds or on alluvial strata. Fig. r.—Diagrammatic section through the Minbu mud volcanoes. In conclusion I may say, that no fiery eruptions have been ob- ` served at Minbu ; the gas is inflammable, but there are no instances on record of its spontaneous ignition. If ignited, the gas bubbles will explode with a faint flame, but every new bubble will have to be ignited again. I have been told that some of the northern wells had been set on fire, where the petroleum occurs in a thick film, but this cannot have burnt very long as no traces of it were visible. CHAPTER IV.—THE PETROLEUM FIELD OF YENANGYOUNG. 1.—GEOGRAPHICAL POSITION, AREA, AND PHYSICAL GEOGRAPHY. According to the latest map of the Survey of India, the village of Yenangyoung? is situated at Lat. 20? 29' N. and Long. 94? 56' E. on the left bank of the Irawadi, in the Magwe District of the Southern Division of Burma. The petroleum field is not exactly close by to the village, but lies some distance inland towards east. This distance has been variously estimated by different visitors as between three 1 The mud volcanoes of Ramri and Cheduba. Records, Geol. Surv. of India, XI, 188—207 (1878). 2 The name of this village has been variously spelled as Ranangoong, Rainang- hong, Yanangheoum, Yunanyaung, Yenan Gyong, Rainoung or even Hong Ragoon, all, however, referring to one and the same locality, Yenangyoung. E Qi ( 95 ) 50 NOETLING : PETROLEUM IN BURMA. and five miles from the river. The latest survey has, however, proved. that even following the winding cartroad, the distance from the river to the central point of the oil tract is exactly two miles and a quarter. Formerly oil was produced at two separate localities, the villages of Beme and Twingon, separated by a tract measuring in a straight line about three quarters of a mile (more correctly 6o to 62 chains), called Kodoung. Since 1887 boring operations have been carried out at Kodoung, and this part forms now the chief oil centre of the field. It may be useful to deal shortly with the different parts com- posing the Yenangyoung oil field, although they are now but of historical interest. (a) The Beme tract, When the stream, which falls into the lrawadi directly south of the village of Yenangyoung, generally styled Yenangyoung- choung, is followed up, it divides at a distance of two and a quarter miles from the river into two branches. The southern branch runs roughly in an east and west direction, and is called Taungle-yo, the northern branch Kunnhitse-yo. Inside the triangle formed by these two streams is the Beme oil field ; at the point of junction lies the small village of Beme. The pit wells are chiefly situated in two narrow ravines, and on the slopes of a bifurcated spur, projecting from the plateau in a westerly direction. The total area occupied by the wells covers 31:2 acres, that isto say, an insignificantly small area. Under the recent settlement the area reserved for the native well diggers has been extended to 83'4 acres, which, including the area occupied by Government wells, brings up the total area of the so called Beme native reserve to go'2 acres. In the light of our present knowledge regarding the geological structure of the oil-bearing beds it may, however, be fairly doubted whether the whole of this area will yield oil. In fact my opinion is that if the area likely to yield petroleum. is estimated at 74 acres, it is rather above than below the mark. It seems that the systematic extraction of petroleum was first started at the Beme oil tract, but it is impossible to say how far C 96-79: | | i YENANGYOUNG. | 51 back this dates. It is unquestionable that the oil field was in full working order at the end of the last century, but I doubt whether the production of oil dates back to prehistoric times as some authors have supposed it to do. Surely the exploitation of an oil field during say only 2,000 years ought to have left some traces be- hind, but there is nothing to point to it being worked more than 200 years. At present the Beme tract is exploited by pits and a few drilled wells; seven in all have been sunk in the Government hold- ings, but it cannot be said that they have been a success from a commercial point of view. In fact every indication points to the probability that the petroliferous sands within the Beme tract are fairly exhausted. (5) The Kodoung tract. Immediately to the north of Beme follows the Kodoung tract, which chiefly occupies the land on the plateau between the Kunnhitse-yo (northern branch of the Yenangyoung choung) on the south and the Aungban-yo on the north. The length of this tract is about 52 chains, and its breadth is at the outside 40 chains ; the area known to produce oil can, for the present, be estimated at the outside at 108 acres ; its western limit has been clearly defined by the results of the deep borings, the northern and southern boundary are fixed, it is therefore only the eastern boundary about which there might be some uncertainty. However, as far as my experience goes, the eastern- most well cannot be far off from the eastern limit of the petroliferous tract, and the above estimate of 108 acres allows a very fair margin in my opinion. The Kodoung area is at present exploited by 58 drilled wells which produce on the average about 12,891 barrels a month. For further details I refer the reader to Chapter IX. (c). The Twingon tract. Immediately to the north of Kodoung and separated from it by the narrow but steep Aungban-yo is the oil tract of Twingon. The area covered by the pit wells forms a somewhat irregular square, =< | (07) Ba. NOETLING: PETROLEUM IN BURMA. limited to the north by the Natsin-yo, and south by the Aungban-yo. Eastern and western limits are less well defined, but it may be said that the wells do not extend beyond the eastern village of Twingon, while west they extend right up to the boundary line of the “Reserve,” The area thus occupied by the pit wells may be esti- mated at about 200 acres. The total area reserved for the native well diggers covers 310'02 acres, but as in the case of Beme it may be fairly doubted whether petroleum is found all over this area. Тһе Twingon tract is at pre- sent exploited by 519 productive wells, which produce by far the larger share of the yield of the pit wells, the average being 7,900 barrels a month, It seems at present at the zenith of its production, in fact, it looks as if it had already passed it. To sum up, the area of the Yenangyoung oil field is made up by— Acres. 1. The Beme tract . . А . 2112 2. Гһе Kodoung tract : š ‚ 108 3. The Twingon . . А +,» 200 TOTAL . 3492 say, 350 acres, or rather more than half a square mile, The land north of the Twingon tract and adjoining it has not yet been thoroughly tested; there are two drilled wells in Block . 2N., one of which has yielded oil, the other not. Both are, however, . closely situated to the boundary of the Reserve. It would, there- fore, be hazardous to say anything definite : but I think I am not far - from the mark if I estimate the length of the whole of the Yenang- young oil tract not to exceed 2 miles, while its average breadth : amounts barely to more than 1 mile. (a) Physical Geography. The country in the neighbourhood of Yenangyoung forms part of the low plateau like land which extends between the high ele- vations of the Shan hills and the Arrakan Yoma, Near Yenan- ( 98 ) | YENANGYOUNG. | 53 gyoung the plateau represents the aspect of a perfect plain, slowly rising inland as far as the eye can see. Buton closer examination one is surprised to find this plain intersected by innumerable ravines and gullies, producing thus the most rugged ground which it is possible to imagine. Atits highest point, Minlindoung, the plateau rises to 534 feet above sea level, but its average height is not much above 480, that is to say, about 250 feet above the high water level of the river. Excepting the Pin-choung, which does not exactly come within the area here dealt . with, there is no stream containing water all the year round. Although deeply cut into the ground the ravines are dry for nearly the whole of the year, and only during the rainy season do they contain water, but owing to their rapid fall the water is quickly discharged, and the ravines remain dry till another downpour causes a fresh flood. It is hardly possible to imagine the suddenness with which these tor- rents appear after a heavy shower of rain, and how quickly they subside again, I once witnessed the Yenangyoung stream, which was nearly dry, rise within half an hour about five feet, and subside to its former level within less than an hour, leaving its bed strewn with masses of debris, | It need hardly be mentioned that а country ОЁ this kind offers the most serious obstacles to communication. The roads have to wind about along the spurs and on the plateau,in order to avoid the continuous descents and ascents when crossing ravines, so that а distance of a mile in a straight line is generally doubled along the road. From a geological point of view, these ravines are very favourable, as, owing to the dryness of the country, vegetation is scarce, and thus the strata are scarcely hidden by the vegetable growth, which in Burma generally conceals all stratigraphical features. It is chiefly owing to these favourable physical conditions that it was possible to study the geological structure of the Yenangyoung oil field ; otherwise it would have been quite impossible to recognize any of the subdivisions in this great thickness of arenaceous and argillaceous beds, which are all exactly alike whether found at the ( 99 ) / 54. NOETLING: PETROLEUM IN BURMA bottom or at the top of the series, Even now the subdivisions - of the Yenangyoung tertiaries, as described in the following pages, must only be considered as a first attempt ; itremains to beseen how - far it will hold good for the larger part of the Burman tertiaries. 2.—GEOLOGICAL FEATURES. The strata developed in the neighbourhood of Yenangyoung may be divided as follows:— A. Diluvium. B. The tertiary system. A —Diluvium. It might perhaps 'be questioned whether this term ought to be applied to the beds which I am here briefly describing; it is not im- possible that perhaps the term older alluvium would be better, as we | do not possess absolute evidence by which the diluvial formations in Burma can be correlated to the same formations in Europe. I consider as diluvial all those strata which rest unconformably . on the tilted beds of the pliocene in such a manner that they can be clearly recognized as having been formed before the present system of drainage was established. Within the limits of the above definition the diluvialstrata can be easily recognized everywhere in Burma, as they are generally found high above the level of the present rivers, and are always cut into by the present drainage. Near Yenangyoung two facies of such beds may be observed, namely :— (1) Lower silt. (2) Plateau gravel. (1) Гле lower silt.—The lower silt may be noticed just south of ` the Pin-choung, but becomes more conspicuous near Kyaukse, where it is a fine silt, horizontally bedded, and apparently deposited in the syn- clinals and hollows of the pliocene beds, which it most closely resembles lithologically, and for which it might easily be taken, if the bedding is not clearly seen. At Kyaukse, I observed on the river bank, that typical pliocene beds, dipping towards west, were unconformably overlaid by a series of horizontal beds of fine silt ; (. 100 ) YENANGYOUNG, | 55 the latter, notwithstanding their great lithological similarity, must of course be of much later date than the pliocene strata. I had no time to spare to examine the lower silt in detail, E it does not seem to contain fossils. (2 The plateau gravel.—Almost everywhere in the central part of Burma, the pliocene beds are covered by a bed of coarse gravel of varying thickness, The gravel consists chiefly of well rolled, large pebbles of white cellular quartz, rolled fragments of silicified wood, and sometimes rolled fragments of fossil bones. Judging from the latter it seems evident, that the plateau gravel has been largely derived from the eroded pliocene beds, but to what parts and in what direction we have to look for the origin of the quartz pebbles remains an unsolved problem for the present. There are conglomera- tic beds in the lower part of the Prome beds in the Chindwin country, but it is doubtful whether the large pebbles in the neigh- bourhood of Yenangyoung could be derived from them. The most astonishing factis the size of these quartz pebbles, ` which are as large as a man's fist, and sometimes still larger. Pebbles of this size cannot have been transported to their present locality from the Shan hills, or the country north of Bhamo where metamorphic rocks occur. In this case the drainage of the country must have ‘undergone considerable changes since these pebbles were deposited ; at present the Irawadi forms only sand banks of the finest sand or silt not only in this part of the country, but also higher up its course. How, there- fore, these quartz pebbles could have been transported to their pre- sent resting place, when their size proves that they could not have been transported a very long distance, and within a long distance there are no older strata containing such quartz pebbles, from which they could have been possibly derived, remains at present a problem which I am unable to solve. I may mention that the presence of these pebbles could not be explained as of glacial origin; so far as known to me, there are not the slightest traces of glacial conditions either in the past or present to be found in Burma. (sig) 56 NOETLING: PETROLEUM IN BURMA. The plateau conglomerate often forms a hard bank, its parts being firmly bound together by a ferruginous cement ; this appear- ance, together with the frequent occurrence of fossil wood, have frequently induced other observers to include it among the Tertiary System, particularly as ferruginous conglomerates, not nearly so coarse however, are of no infrequent occurrence within the plio- cene division, Its unconformable position on pliocene beds will, however, readily distinguish the plateau conglomerate. So far as known to me it chiefly occurs within a certain height above the present level of the river, apparently not exceeding 400 feet above sea-level, and generally between 300 and ¿00 feet. It usually occurs in isolated patches capping the pliocene beds, but more extensive deposits are by no means infrequently found. I am not in a position to state exactly what are the relations between the lower silt and the plateau gravel; it seems quite evident that the lower silt is overlaid by the plateau gravel, but I also noticed between Kyaukse and Yenangyoung a conglomeratic bed Which could not possibly be distinguished from the plateau gravel, interstratified with the lower silt. | The above outlines of the diluvial strata of Burma do not aim at being exhaustive, and I only mention the subject, since the plateau gravel has been so frequently wrongly identified with the tertiary system, | B.—The Tertiary system. In the neighbourhood of Yenangyoung only the younger tertiaries appear on the surface, but this does not (hak the probability that older tertiaries occur below. I,—THE PLIOCENE OR IRAWADI SERIES. (a) Zithological characters.—The principal rock of the Ira- wadi series is a very soft, friable sandstone, perhaps better termed | sand rock. It is generally of light yellowish colour, sometimes almost | white. In the lower parts strings of nodular or kidney shaped concretions of hard silicious sandstone are frequently met with ; in I 02. ^n YENANGYOUNG. | 57 the upper part calcareous concretions of various irregular shapes resembling fossil roots or bones, are very common. ` Of more subordinate importance are beds of ferruginous conglo- merate, generally forming thin and irregular layers, which resemble shingle deposits. The thickest of these beds is found at the base of the division, where it forms a very constant horizon, which I shall have occasion to describe further on. Still more subordinate are argillaceous beds; now and then they form layers of some thickness, but generally they occur in thin beds; their colour is a greenish brown of various shades. (b) Palzontological characters.—Near Yenangyoung the Ira- wadi series contains numerous specimens of bones and teeth of vertebrates. The specimens are particularly common along the river bank between Yenangyoung and Nyounghla, but fragments may be picked up almost everywhere in the more conglomeratic beds, As I have discussed the relations of this fauna in a previous paper, it is superfluous to go over the same ground again. It will suffice to say that the species determined, excepting those which are indigenous to Burma, are all identical with Siwalik species. With regard to the recurrence of species | may mention that frag- ments of Crocodtlzs sp. (cf. biporcatus) and Gavialis (cf. gangeticus) preponderate. In fact there is hardly a conglomeratic bed in which at least a few fragments of these two species may not be found. Next come Chelonian bones, in particular Zrionyx sp. Then follow the other animals, among which Hippopotamus irravadıcus, Acerotherium perimense, Mastodon cliftii are more frequent than the other fosms, which are generally very rare. In conclusion I may say that the specimens are very irregularly distributed; the river bank between Yenangyoung and Nyounghla, along which in former years such rich collections have been made, barely yielded a few fragments in 1895. 1 The Development and Subdivision of the Tertiary system in Burma. Records of the Geol, Surv. of India, 1895, XXVIII, pp. 50—86. ( 103) .58 NOETLING : PETROLEUM IN BURMA. Besides the vertebrate fauna, silicified wood is extremely common in the Irawadi series, Huge logs and smaller fragments may be found almost anywhere throughout the beds. As I have expressed my views with regard to the origin of the fossil wood in the paper quoted, it is unnecessary to repeat them here. | Excepting the two species Cyrena (Batissa) crawfurdi and ` Cyrena (Batissa) petrolei which occur at the very base of the Irawadi series, and which also descend lower down, the beds forming the latter have so far been found to be absolutely destitute of invertebrates. (c) Local subdivision.—\n the neighbourhood of Yenangyoung, the Irawadi series attains a thickness of 4,630 feet measured from the base of the zone of Hippotherium antelopinum to the bank of the Irawadi. It is, however, quite certain that this does not by any means represent the total thickness of the division, which must be much larger even near Yenangyoung, but, owing to the want of more accurate maps, it was impossible to estimate the thickness with any accuracy. It is beyond question that the subdivision of so lithologically uniform a sequence of beds, of a known thickness of not less than 4,600 feet is extremely difficult, if not altogether impossible. It seems, however, as if certain species of the vertebrate fauna were limited to certain horizons. Whether I am right in this supposition remains to be seen, when the Irawadi series has been studied in greater detail in other parts of Burma; but I am absolutely sure that certain species are restricted in the neighbourhood of Yenan-. gyoung to the lower parts of the division, while others have so far been only found in the upper parts. In descending order I distinguished three stages— I. Sandstone, apparently containing no vertebrate remains, but plenty of fossil wood. 2. Zone of Mastodon latidens and Hibpopotamus irravadicus. 3. Zone of Hippotherium antelopinum and Acerotherium peri mense. The three horizons are of very unequal value as regards thick- ness, inasmuch as the lower one is of not more than 20 to 25 feet in '( 104 ) YENANGYOUNG. | 59 . thickness, while the two upper ones include the remainder of the Irawadi series. It is quite possible that the latter is capable of a further subdivision, but owing to the inconstancy of the fossi- liferous beds, and the uniform lithological character, I have not been able to distinguish more than two zones. [n fact the subdivision . of the beds above the zone of Mippotherium antelopinum into two parts is somewhat artificial, as no definite boundary between the two can be given, owing to the sameness of the lithological character of the strata. Negative evidence, the absence or scarcity of fossil remains, is in fact the only distinguishing feature. The zone of Mastodon latidens and Hippopotamus irravadicus is formed by soft yellow sand rocks with subordinate conglomerate beds, and is characterized palaontologically by the two above- named species, which almost certainly do not occur in the lower zone. | The zone of Hippotherium antelopinum and Acerotherium pert- mense forms a most conspicuous horizon of the upper tertiaries near Yenangyoung. Inthe form of a dull red band it is visible at long dis. tances, running continuously over hills and ravines, and encircling the Yenangyoung oil field. In fact the presence of this bed has helped in a sreat measure to interpret the structural relations of the, Yenan- gyoung oil field. Lithologically this horizon is represented by aferru- ginous conglomerate, which varies somewhat lithologically; at some places it isa rather incoherent agglomerate of irregularly shaped concretions of a ferruginous clay, at others it contains numerous quartz pebbles cemented by a hard conglomeratic sandstone, at others again it is an earthy iron ore, of a bright red colour. In thickness it varies also, being of not more than 10 feet thick- ness at some, while at other places it swells out to about 25 or 30 feet. Palzontologically this bed is characterised by the frequent occurrence of Hippotherium antelopinum and Acerotherium peri- mense, neither of which rise into higher horizons. Besides these Crocodilis sp. Gavialis sp., Trionyx sp. are very common. Locally, particularly east of Minlindoung, it contains hundreds of the two (2405 )) бо NOETLING: PETROLEUM IN BURMA, species Cyrena (Batissa) crawfurdt, Noetl., and Cyrena (Batissa) petrolez, Моей. It must also be mentioned that the curious chipped flints, which have been generally recognized as being of artificial. origin, have been found in this bed. As I have devoted a special paper to the occurrence of these flints,! I need not recapitulate the facts here. As regards the horizontal extension of this zone, it may be said | that at least in the immediate neighbourhood of the Yenangyoung oil field, it forms a very constant horizon, which disappears towards north below younger beds. In a southern direction, towards Minlindoung, the individuality of this bed becomes less expressed and ` itseems that it dies out further to the south, If the reality of this horizon be questioned on this ground it must not be forgotten that the bed forms but one of the conglomeratic beds, of so frequent occurrence in the Irawadi division. Ав at the same time it seemed to be well characterized by the occurrence of certain species, it appeared to me quite admissible to distinguish it as a local horizon, but it cannot now be settled whether it forms a distinct horizon in the Irawadi division. I particularly wish to emphasize that the above is but a first attempt to subdivide the pliocene of Burma on a palzontological basis, which will have to be confirmed by future researches, particu- larly in the Siwalik hills of India, 2.— THE MIOCENE OR PEGU SERIES. (ға) The upper miocene or Yenangyoung stage. a. Lithological characters.—It is chiefly composed о! olive | coloured clays, always well stratified, and sandstones of the same colour, which usually contain strings of hard concretions of consi- derable size. A good distinguishing feature is found by the pre- sence of gypsum, which occurs in large crystals in the argillace- ous beds. This mineral is so strictly limited to the beds below the 1 Records, Geological Survey of India, 1894, XXVII, p. 103, and Verhandl. d. Berlin. Anthropol, Gesel., 1894, page 427. ( 106 ) YENANGYOUNG. 6I zone of Hippotherium antelopinum, but above the Prome stage that it serves as a distinguishing feature. It may also be mentioned that the beds of this stage are intersected by numerous veins filled with eruptive mud (see page 80). | à. Palzontological characters.—In the neighbourhood of Yen- angyoung these beds are particularly destitute of fossils. With the exception of the two species already mentioned, víz., Cyrena (Batissa) crawfurdi and Cyrena (Batissa) peirolei, which have been found in the topmost bed, no other fossils have hitherto been met with. It also deserves to be mentioned that the few fragments of fossil. wood which are occasionally found are always carbonized, never silicified, ЖК - The total absence of fossil remains in this stage, excepting the two species already mentioned, is very remarkable, because further to the north, near Singh a fine marine fauna was discovered in the same horizon. The thickness of the stage is about 1,100 feet, but in (һе absence of any fossils it is useless to attempt further Subdivision, particularly as it will be pointed out further on (see page 77) that the beds are of very limited horizontal exten- ‘sion, When the sections described are examined it will be ap- . parent that a thick bed of sandstone may abruptly terminate, and be replaced by an equally thick bed of clay, thus showing the uselessness of subdividing a formation of so uniform lithological characters. (25) The lower miocene or Prome stage. a. Lithological characters.—In striking contrast to the yellowish and brown tinges of the upper tertiary beds, the lower miocene is always characterised chiefly by bluish, or, in some cases, greyish colours, T | As in the previously described divisions, the principal rocks are sandstones and argillaceous beds, but there are no limestones or shales, ( 107 ) 62 NOETLING: PETROLEUM IN BURMA. The sandstone is very fine grained and usually very soft, but sometimes it contains more silicious cement, and in that case either thin continuous layers of a very hard, silicious grey sandstone are formed within the softer beds, or the silicious matter concentrates in the shape of globular concretions, both of which constitute great obstacles to the limited resources of the native well digger. When the sandstone is fairly soaked with oil it exhibits, when fresh, a fine grass green colour, which, however, very soon changes toa dirty brown, After being exposed for some time to the heat of the sun, the oil evaporates, and then it is seen that the sandstone is of the usual pepper and salt colour. The argillaceous beds generally consist of a very tenaceous, bluish clay, forming either continuous beds of considerable thickness, or thin layers alternating with equally thin beds of sandstone; the latter facies is known by the drillers as “shale.” Within the area of the Yenangyoung oil field only an — part of the Prome stage comes to the surface, chiefly in the form of thin alternating beds of argillaceous and arenaceous character. The lithological characters can generally only be ascertained by the debris heaped round the mouths of the native wells. б. Palzontological characters.—Fossils are apparently very rare, and I only once succeeded in finding a few in a conglomeratic bed made up of rolled lumps of clay, carbonized wood and numerous fragments of bones, about 156 feet from the surface. This bed was not more than about 4 inches in thickness and was intercalated in sand slightly charged with petroleum, and must have been of purely local character, as it does not seem to occur anywhere else, The fossils were not particularly well preserved, excepting some osseous fragments and teeth; the calcareous substance of the other fossils had been entirely destroyed by the action of the sulphuric acid, the presence of which is explained by the frequent occurrence of iron pyrites in this bed.! ! See my paper on the Development and Subdivision of the Tertiary system in Burma ; Records, XVIII, p. 59. ( 108 ) YENANGYOUNG, | 65 c. The occurrence of petroleum.—At Yenangyoung the upper miocene beds are of great economical importance, because of the petroliferous beds they contain, which have yielded, comparatively speaking, a large quantity of petroleum. It has been proved toa certainty that in the Yenangyoung oil field the petroleum is always associated with the arenaceous beds, that is to say, the sandstene is always saturated with petroleum, while in no case is it present in the argillaceous beds, or, as might perhaps be expected, gathering in their fissures or cracks. The clay beds seem to act like a hermetic seal, as is well illustrated in all cases where native wells have just reached the upper part of the petroliferous sands. It seems that towards the top thin beds of clay alternate with the sand, which finally passes into clay. The sand is always charged with oil, and exhibited its fine green colour, while the clay contains no trace of it. I also frequently observed that when breaking a fair sized lump of clay and, as is often the case, it contained a lenticular thin layer of sand, this sand was often fullof oil, although no trace of it could be seen superficially. I want to put stress on the fact that I did not observe this once, but repeatedly, and that I was very particular in verifying the correctness of this observation, which seemed to me of the greatest theoretical importance, inasmuch as it sheds alight on the origin of the oil, I may remark here that this mode of occurrence Ғ/д renders it impossible, that the petroleum should have originated at some other place and migrated to its present receptacle. It is impossible to imagine how it could have penetrated a fairly thick i layer of clay without leaving the slightest traces of the way is E | followed, and eventually gathered in a sandy streak. If this view is “Ж. taken, the question might well Бе raised why, if such а force existed, JAM was not the petroleum again driven out from the sandy layer. To me this proof seems convincing that either the substances eventu- ally changed into petroleum, or the petroleum itself must have ( 109 ) 64 NOETLING: PETROLEUM IN BURMA. already been absorbed by the sandy layers before the latter was hermetically sealed up and surrounded on all sides by a covering layer of clay.1 This instance of petroleum occurring in sandy layers, surrounded on all sides by clay, is repeated on a larger scale in the petroliferous sands, although it is very difficult to prove, in this case, their entire isolation and the absence of any communication with other beds. | The deep wells have, however, given in some instances such a sequence of strata that it is impossible to interpret them in any other way, but that a, comparatively speaking, thick bed of sandstone is intercalated in and surrounded on all sides by argillaceous beds. The presence of the petroliferous sand 2 (a) in Wells No. б (а), 10, ‘and 8, and its absence in all the surrounding wells, can hardly be explained in any other way except that it forms a lenticular arenaceous mass imbedded in clay. I may further add that I actually observed a thick bed of sandstone dying out in an argillaceous bed, —a subject which will be dealt with in a subsequent chapter. | To me it seems therefore beyond any doubt that the petroleum stored in the petroliferous sands if the Yenangyoung oil field must be indigenous, and that the assumption of an extraneous origin, and the migration to its present receptacle, is incompatible with the observed facts. Whether, however, the view of the indigenous origin of the Yenan- gyoung oil field be accepted or not, the deep borings have proved that it occurs within the area of the Yenangyoung oil field in at least six different horizons. It may be almost considered as certain that the above number does not represent the total of the petroliferous sands 1 It may be advisable to poirt out that this conclusion is not so fully established as Dr. Noetling's languages would suggest. The penetrating nature of mineral oil is weli known, and as Mr. Н. В. Medlicott wrote in 1886 (Rec. XIX, 191),“when we find geodes filled with successive layers of minerals in the midst of compact basalt it is difficult to place limits on the possibilities of permeation." Dr. Noetling's own observations on the connection between geological structure and distribution of petroleum in the Yenang- young oil field indicate that the present differs from the original distribution of the oil ; this, however, is compatible with the original inclusion of it, or the materials from which it was derived, in the beds in which it is now found—Ed. „{ 110°) YENANGYOUNG. E. contained in the Prome division, but unless proved by ‘deep borings nothing definite can be said about it, It also seems quite certain that the different petroliferous sands vary greatly in horizontal extension, and that therefore complete sequences of the petroliferous Sands are by no means found in every single well. Та fact, the irregularity of horizontal extension has been one of the chief difficulties with regard to the correlation of the single beds observed in the different drilled wells: In the following enumeration the petroliferous sands are numbered in descending order beginning with the one nearest the surface. I. The first oil sand.—The first oil sand is generally found immediately below the beds of the Yenangyoung stage, at depth varying from about 80 to 100 feet from the surface. Its thickness is never great, being about 20 to 30 feet, but locally it may increase somewhat. In the latter case it is very probable that tre argilla- ` ceous bed, which elsewhere separates the first and the second sand, has disappeared, and both form a continuous stratum. Instances will be frequently noticed in the boring registers which indicate this probability, It is remarkable to note that the first oil sand contained only slight traces of oil in two of the northernmost wells, No. 21 and A at Kodoung, while in all the other wells it was unpetrolifer- ous, being either dry only containing water. . On the other hand it is. quite certain that it contained a considerable quantity of petroleum within the Twingon and Beme areas, and only quite recently this has been proved by pit wells in the south-western corner of the Twingon area. The oil produced by this sand seems to be the heaviest oil, in- &smuch as its average specific gravity is higher than that of any of the lower sands. 2. The second oil sand.—' This bed is found at a depth of about 150 feet from the surface ; its thickness varies, but it never. exceeds 50 feet. As already stated, it is possible that in some parts of the oil field it forms a continuous bed together with tbe first oil sand, Like the latter it never contained any oil within the limits ` оё the Kodoung tract excepting well No. 40, where a small quantity F N (c TOR. у 66 NOETLING: PETROLEUM IN BURMA. of petroleum was found in a bed which may be correlated with the second oil sand, On the other hand it must have contained consider- able quantities of petroleum to the north and south of Kodoung as there are still a good many of the pit wells which draw their oil from the second oil sand. As regards the chemical quality of the oil of this horizon, it is almost certain that it is on the average of lighter specific gravity than the oil from the first sand, although a little heavier than that of the fourth sand. 3. The third oil sand.—The independence of this layer seems questionable ; во far it has only been observed in few wells to the ` north of the Kodoung, such as No. A, No. 6, No. 8, in all of which cases it is separated from the next following fourth sand by a com- paratively thin bed of clay, which renders it very probable that this layer only forms thetop of the fourth oil sand, locally separated by an intervening bed of clay. In all cases it contained a considerable quantity of petroleum. | 4. The fourth oil sand.—Thisis the bed which supplies the greater quantity of oil found at the Yenangyoung oil field. It has been gene- rally found at depth ranging from 220 to 250 feet from the surface, but of course the depth must vary for different reasons ; and as regards thickness it varies so much that there are hardly two wells where it exhibits the same thickness; it may not be more than 20 or 25 feet in one well, while it exhibits a thickness of nearly 300 feet in another. The reasons of this variation will be dealt with in another section. The fourth oil sand contains petroleum throughout the Yenangyoung oil field; it seems that the oil from this sand is lighter in specific gravity than that of any of the upper sands, inasmuch as its average specific gravity is 0'8766 or o'8921 at 60? F. With regard to the deeper oil sands, it must be said at once that only the merest indications can be given, because only a few wells have reached a greater depth, and these wells are so far distant from each other that a correlation of the various strata observed seems almost impossible. The difficulty is particularly increased» because it seems that the various sands noticed in the different 5 If.) AE YENANGYOUNG. 67 wells are most probably only parts of one and the same layer, separated by local argillaceous beds. It seems, however, certain that below the fourth oil sand there is a fifth layer containing petro- leum, which most probably reaches a great thickness. It has been observed in wells No. 56, No. 51, No. 54, No. 60 and No. 59, but has notso far yielded a very large quantity of petroleum. Only in one well No, 54, but perhaps also in No. 13, a sixth oil sand seems to have been found below the fifth horizon, but no details can be given about its extension. As по samples of petroleum have been obtained separately from either the fifth or sixth oil sand, nothing can be said about the specific gravity of the petroleum they contain. So far the few wells which went deeper than the fourth oil sand seem to have proved that the lower sands contain only a small quantity of petroleum. Whether this applies also to still deeper strata remains to be seen, and nothing definite can be said at present, and only an actual boring can decide. It will be useful to record in this section a few more observations _ which are intimately connected with the occurrence of the petroleum. These are: The migration of the petroleum within the beds in which it is contained at present, and the relations between the occur- rence of gas, petroleam, and water within the whole series and within a single bed. Although the assumption that the petroleum has migrated from other places to the beds in which it is contained now, must be rejected for very strong geological reasons, it cannot be denied that a certain amount of migration must take place within the petroliferous bed itself. In fact, it would be difficult to believe that the petroleum remains in an absolute state of rest inside its recep- . tacle. There are two facts which almost prove conclusively that a certain amount of movement of the petroleum must take place, These facts are— (a) The periodical rise and fall of the production with the season, (6) The continuity of the production of the deep wells. (a) The periodical rise and fall of the production during the F 2 ( 113 ) 68 NOETLING: PETROLEUM IN BURMA year.—]f we note the months in which the maximum and minimum production took place, we see that it was recorded in :— in 1886 the maximum was in August, the minimum in . July. 1887 ,, 19 „May, i b March. 1888 , - » May, B М3 February, 1889 رو‎ » » ]une, » Ў: January, 1890 ,, » » July, T b February. 1891 ,, y » ]une, » А January. 1892 , T y September, ,, » February. 1893 , » и: March, $i ai February. 1894 ,, - », December, ,, » February. We see that during the nine years over which the observations have extended, the minimum production has been noted eight times during the first quarter of the year; only once, in 1886, was it observed in July; as, however, 1886 was by no means a normal year, and as it is recorded that in July of that year oil was drawn only during about 20 days, we may disregard this observation as unreliable. The maximum production was noted seven times out of nine during the months May to September, namely, twice in May, twice in June, once in August, July and September, it was only once noted in March, and once in December, but it may be added that in both years the maxi- mum noted only slightly exceeded the production of the months of July and May respectively. | To make the matter clearer still I have computed the average production of each month of the year, which is as follows :— A o Ht ne ° 2 : y - 564,498 viss Reba Ll 0$ 2. . ° . . ° 520,372 » March Ж А - ` А : ° 566,719 » April . ” A 2 ° у а қ, 1 535312 ,” May . Р . e . . . Ее 591,984 , [Lc AN ТИ Lr MEI July . . S HITS - - ° . А 664,653 nf August - = . y ° Е . . 645,233 » September . а ‘ А Р - ° e; 011,532 , October A : - A - i à Е 622,608 , November . Е . ; . " . 2 оза” December , ? . e 596214 » * April 1891 has Е s p u y as an anomalous month. + July 1886 ditto ditto ditto, ( 14 ) YENANGYOUNG. . 69 rom the diagram fig. 2, that there is unquestionably a periodicity ‘of ES which is intimately connected with the season. The qe leso| | | 570000 560000 550000 540000 550000 1520000 ` 1510000 | |520000 || |510000 2. Diagram showing the mean monthly yield of petroleum from 1886 to 1894. - begins with a comparatively low production in January, which owed by a quick drop in February, and a sudden rise in March, ed its maximum in July, a rather sudden, but not large, drop place up to September, when it again slowly rises till November, to falllargely and suddenly in December, a drop which lasts till гү Eu. Now, is it a mere сашсоелсе ne the curve, as oe he fall of the Irawadi ? ` Unfortunately no exact observations regardi ing the river gauge have been made at Yenangyoung, but experience. has proved that the river reaches its lowest level in u | February, a small rise takes place in March, probably owing to the |. snow water coming down from the upper regions of the catchment b. rea, and then another fall takes place in April, From May the river s pat it hasreaghed i а 1 maximum level during the months of June, 3 (TE >) DM өр ~ ' 7 DUMP y LV ee Lut, 1 £ ИҢ «эшл ха ` Жы Қа! М * v КУД «NY . ж ЖҮ ç E - Г ^d i “ n La È oe 5 ГЕ. М " ы EN EU 1 h % ? a. š po = L " A ^ : j aval E Y Мед N ° К wars Ё 3 ‘ М E dox , " ma M іші: га t Ж“ bi А ” 2 A » ыты MES f ^ | С А қтары a t.a ma ` » B ME 74 ye Y 72 NOETLING: PETROLEUM IN BURMA. To me it seems obvious that there exists a connection between the height of the river level and the quantity of the production of the native wells, and, as I have already pointed out, that there is a relation between the activity of the mud volcanoes and the height of the river (see page 44), it is not unreasonable to suppose that the | same influence which stirs up the mud wells affects the petroli- ferous sands in such a way that the discharge of the oil is more abundant during the rainy season than during the other months. The production of the drilled wells exhibits the same phenomenon, al- though it is here not so conspicuous for reasons which are easily explained, In the pit wells the oil slowly filters into the well, there to gather, while it is pumped oat in a permanent stream from the | drilled wells. Probably, therefore, the quantity obtained from the latter does not represent the quantity which would be obtained if the oil were allowed to collect slowly in the bore hole, as in the pit wells. The explanation of this strange phenomenon is by no means easy because we know unfortunately little or nothing with regard to the movements of liquids in rocks at considerable depths, and under con- siderable pressure. We may, however, at once dismiss the theory of the influence of the temperature; quite apart from the fact that the temperature is usually highest when the production is lowest (February to April, it is almost certain that the beds which supply the oil are beyond the yearly range of the changes of temperature on the surface. But perhaps the following theory will afford an explanation. It seems very probable that the petroliferous series is intercalated in an arenaceous formation of considerable thickness, permeated by water. We further know that the chief oil producer, the fourth oil sand, is found at a depth which differs not materially from the high water level of the river. I believe we may safely assume that when, during the rains, the river rises to sometimes fifty and more feet above its low water level, the ground water will also rise, and this in its turn ` presses on the petroliferous sands and forces the oil to fow more freely. | | ) ( 16 ) YENANGYOUNG. | 7! However that may be, it is beyond doubt that the oil flows more "freely during certain months of the year, and this can only be ex- plained by the assumption of certain currents existing in the oil sand. | | (5) The continuity of production of the drilled wells,—1t is most remarkable that although some of the drilled wells are over six years of age, their production has not become less. If these wells. derived their supplies from only a limited area they would have - already shown signs of exhaustion. The steady production of the wells seems to indicate that the oil which istaken out is immediately replaced, and this involves the assumption of the existence of a current of oil which is moving towards the deep wells. | ` (e) Relations between the occurrense of water and petroleum.— E Yu With regard to the general relations between the occurrence of water and that of oil within the area of the Yenangyoung oilfield, the deep wells have revealed some facts, which do not seem to be quite у compatible with the theory that we should have gas at the highest D. ` points of the anticlinal, oil in the centre, and water below. Whatever | may be the value of this theory for localities, it does not seem to hold ` good for the Yenangyoung oil field, where there is apparently an Ем irregular distribution of the above named three substances through- A out the series, I must, however, put stress on. the words throughout | the series, as it is quite possible that the theory holds good within the compass of one and the same bed. It seems certain that . within the same bed the oil always seeks to rise to the highest points because the most prolific wells are unquestionably situated at such points where the petroliferous beds have risen highest above the sea level, and it is also certain that whenever petroleum and water are associated in one and the same bed, the former always rises above | the water, with the exceptions of wells No. 48, No. 61 and No, 54, Fo ME where it has been stated that water sand was found on the top of the oil sand without being separated from it by an argillaceous parting as it is generally the case. А (117) 72 ` NOETLING: PETROLEUM IN BURMA. The boring record of well No. 48 is— 40 feet blue clay from 165 to 205 feet. 35 » Water sand „ 205 to 240 > Рр 115 ” oil sand ” 240 to 555 » Unless we assume that there must be an argillaceous parting ` between the water and oil sands the case is remarkable. The instance of No. 54 is even more striking ; the boring record states — 25 feet blue clay . . from 400 to 425 feet. 75 » grey water sand 4 “ » . 425 to 500 feet. 175 » dark sand | . > » 500 to 675 » So ,, oil sand with slight show of oil ,, 675% 725 IS , Of blue сау . : = u 725 to 740 К Provided that this record is correct, we would therefore have a continuous arenaceous series of an aggregate thickness of 300 feet, containing water at the top, being dry in the middle, and petrolifer- ous at the base, inclosed between impermeable beds of clay. With regard to No. 61, the case is stranger still; some 60 feet of white sand, with some water rest on the top of roo feet of oil sand, without apparently a separating medium ; the oil sand in its turn rests on 5 feet water sand. If this boring record is correct, we would have an arenaceous series of more than 165 feet in thickness, a layer of petroleum in the middle, and a layer of water on the top and at the base which seems to be so contradictory to all laws of specific gravity, that for the present I must record it with some doubts. | | With regard to the distribution of water and petroleum through ` the series, it is quite certain. that they occur quite independent of each other; but that in this casé the petroliferous and water bearing beds are always separated from each other by impermeable beds of clay. it would be useless to go into details at length, a glance at the sections or at the boring records will prove this, but still I may be permitted to thention the two deep wells, No. 13 and No. 54, in greater detail. In No. 13 the following sequence of water bearing, ( 118 ) | y ^" 4 Д . a | | ; ' Мұ? Г Ë. ^ А СЪ а? , 4 Р la + ñ DL pe A e К | i hi EPR Ягу TIN pn hi ; қ ] 2 AS A AMO AU o Ç А PUE. ` ы E ' А j YENANGYOUNG. | 73 ` y Бей ў 4. . ; | . ° oliferous and argillaceous beds has been recorded in descending 104 feet dad ТСМ ТАН a . Yenangyoung stage. : ` gy Shale and clay . . . | » water sand. : ° А E » cay . . . . Cial. sand -e . А = ә water sand, . . ‹ » Shale and clay . ° ° » Water sand. . es ! » Shaleandclay . А . Hine seine. » water sand. BE » Shale and clay . . "E » water sand, . . д » clay | . D ° . „ Water sand, š . : ә Shaleand clay . 4 E PUO ЧАН ef wes 4 » Shale . . à CM are ЕРТЕДЕ with мш Тһе second bed forms prob- wt only of the bed containing petroleum at the top. Between I p EC strata ted petroliferous beds have п er we ig Mis in every instance Ж аре ы ¿alasan beds p water oed and ae strata, and that it 1s' re- ing i is the sequence in TEPE order :— = 80 feet surface sand, d e р blue clay. HAREN ES | 60 black sand . FREE ay wao . e (E) i ЫЗ; grey water sand » ДҮ Ф ° ° ° (2) kon 5, blue clay. aie 125 „ dark sand with slight show of oil, id water I, 25 > blue clay. г | YS. АН N | P. t SET | | (19) к Pu Se T 4 SU. Y | қ í ERS “ | » " 2 n | j ғ " қ u AY SA: | Жы) E w p Um ме, x * a L Cv aua, y R к n ж 7 74 NOETLING : PETROLEUM IN BURMA. 75 feet grey water sand . . z : ° (3) 175.;, dark sand. % ; ^ (4) 5O ,, oilsand with slight as of ol . «T 15 „ blue clay. | 20 , grey water sand. ° ° ° ° (s) ° 40 , blue clay. 25 y oil sand with slight show e oil . . Ш. 25 , blue clay. 20 , grey water sand es . e (6) 30 ,, tough blue clay. 30 , white sand . . . . ç (7) 20 , blue clay. IO , black sand ə . . . . (8) If we assume that the black sand differs from the grey sand, and there is no reason for any other conclusion, we notice eight different sands, four of which are water bearing, four apparently dry ; while distributed between these, there are three petroliferous sands. With the exception already mentioned, they are, however, all separated from each other by beds of clay. Another feature must be mentioned; there is no doubt that one and the same arenaceous bed has been found to be water bearing in one well, while it was dry in another. It even seems, if I rightly interpret the boring registers, that the first and second oil sands are | unproductive at Kodoung, while they certainly contain oil at Twin- gon and Beme. We may even go a step further and say that some of the wells like Nos. 64 and 68 seem to indicate that the same bed, which yields oil elsewhere, contains only water in these wells. The first observation is not easily explained, unless it be by the rise and fall of the ground water. We may suppose that its level rises and sinks, and when it is high, water is found, in one and the same bed, at a higher level than in a well close by, where the same bed is said to contain no water, because the boring was made when ground water stoodlow. Unfortunately it is not easy to ascertain from the boring registers how far this supposition is borne out by facts,and as eventually the bore must be tubed to shut off the water found, perhaps at a E depth, it is impossible to say А 120 Y) T QE 1: YENANGYOUNG. | 75 whether a certain higher bed, which was dry at the time when it was drilled through, contains water during other seasons of the year. The second feature is more easily explained; we may well imagine that, with the gradual removal of the oil from the petroli- ferous sands, the water gradually rose under the hydrostatic pressure and replaced the oil. As the two wells above mentioned have been drilled near the margin of petroliferous tract, such a supposition is by no means improbable. | As the last feature in the occurrence of oil, we have to deal with flowing wells and the presence of gas. That gas emanates from the petroleum can be easily seen in the wells, in some of which the evaporation oÍ gas is so rapid that the surface of the pool of oil gathered in the well is in an agitated state, as if boiling, and gas bubbles are incessantly rising. No gas pressure worth speaking of has been observed in any of the drilled wells, although there is unquestionably a small pressure, but insufficient to produce flowing wells. With regard to this the Yenangyoung oil field has not proved a success, and all the oil must be pumped from the wells; as far as our present experience goes it is also very unlikely that flowing wells will be found within the limits of the Yenangyoung oil tract, : In conclusion a few words must be said about the curious occur- тепсе of gas recorded in wells Nos. V, VI and VII just at the southern limit of the Beme oil tract. In No. V two consecutive beds contain- ing gas were found, the upper between 9r and 205 feet from the surface, the lower at 286 to 330 feet; in No. VI the gas vein was struck at 255 feet, and in No. VII at 355 feet from the surface. The presence of gas just at this part of the oil tract, that is to say, its southern limit, is not easy to explain, particularly if we recollect that ` the gas is found here at a lower level than the oil in the other parts, unless we assume that the sand containing gas represents the fifth oil sand of the other deep wells. The only manner by which the presence of gas at this part of the oil field could be accounted (FES) 76 NOETLING: PETROLEUM IN BURMA. for is the theory of the intersecting folds, which will be discussed in a subsequent chapter. We may now sum up in a few words the facts which have been ascertained with regard to the occurrence of petroleum in the Yenangyoung oil field. These are :— I. The petroleum is indigenous to the strata in which it is found. ` 2. The petroleum is restricted to the arenaceous beds, and tends to rise within them to the highest points. 3. Whenever water and petroleum are associated in the same bed, the petroleum generally rests on the water. There seem how- ever to be a few instances, which would point to an exception to this rule, although they áre not quite authenticated, and open to doubt. 4. Throughout the series water and petroleum may occur inde- pendently in different beds, following each other vertically, but in this case they are, with few exceptions, well separated from each other by impermeable beds of clay. C. Local subdivision of the lower miocene or Prome stage.—The Prome stage being almost exclusively known from deep borings, | it would be rash to attempt any general subdivision of this sequence of beds, which are all so much alike in their lithological characters ; but fortunately we havea horizon, containing some very charac- teristic fossils, among which Anthracotherium silistrense takes the most prominent place. As this species has not yet been discovered in any of the higher beds, it may perhaps be admissible to designate the upper Prome beds as the horizon of Anthracotherium silistrense. ia In going through the boring registers anything like a general subdivision of the beds recorded seems an almost hopeless task. It is impossible to subdivide a series of an approximate thickness of 1,100 feet, which consists of nothing but beds of clay and sandstone with no further distinguishing characters. The difficulty is still fur- ther increased by the fact, that the beds composing the petroliferous ( 122 ) YENANGYOUNG. 77 takes place within a distance of a few feet (see page 78). д All that we can therefore do under these circumstances is to ` investigate whether a certain sequence of beds can be recognized in ЕУ the boring registers which, with restrictions, may hold good for ` the area of the Yenangyoung oil field; but this will be discussed M x toy ether with the sections of the deep wells. | SECTION 3.—STRATIGRAPHY. | A— General Features. — РЯ (a) Unequality of sedimentation. «t М N D Local E ovv and ak ши ge Tone of the In the Aungban-yo or in the Ayatpo-yo good illustrations of omplete thinning out of beds may be observed. On the northern > of the former a bed of bluish somewhat sandy clay appears suddenly within a series of sandstone; it attains very quickly e considerable thickness of 50 feet within a few feet, and. then ' thins out, disappearing towards. east and north under er beds; its final termination is not seen. The section "o ted in the Aytapo-yo shows this feature still better. The | be d just mentioned is represented at its southern end by thinly a . bluish clay alternating with sandy strata, where its top | ds about 50 feet above the bottom of the ravine. Proceeding north- 7) CM it dips slowly in that direction until it disappears, and is placed by a series of soft, whitish or red sandstones in irregular thick ks, which contain at least four distinct beds of bluish «57 trace». ‚78 NOETLING : PETROLEUM IN BURMA, able for a considerable distance. The lowest of these beds, about 5 feet thick, is separated from some bluish shales by a bed of white sandstone of 6 to 7 feet in thickness; it begins quite close at the south- ern end of the ravine, quickly attains its greatest thickness, and then runs as a very regular band, following the general dip towards north, until it disappears. About 30 to 40 feet higher up two other argilla- ceous bands appear, one near the southern, the other towards the northern end of the gully ; both begin as very thin beds, which quickly increase in thickness, but thin out completely furtheron. A very good instance is however the last bed, which has a maximum thickness of about 20 feet, while for a considerable distance it is reduced to a parting of about 2 inches. It begins as usual as a thin layer, which quickly swells and then thins out, forming a thin, hardly preceptible layer, once more suddenly swelling out to a thickness of about 25 feet; this continues a short distance to die out gradually (see plate JX). Another very good illustration of the sudden change of argillaceous to arenaceous beds, within the same level, may be seen at one of the ravines on the western side of the Twingon oil tract, between wells No. 159 and No. 161. 77. 2 O [27777 T Mrara I NADO L CITI RRA 222424 = — LEO CRTR IRA ES III AA TE ITAYRERIIETIM 023 01207247. 222. 7777222711 zer 7717/777771312 777777277 7 ull ALTA HER 2 RR EEE а 4 7 227 47272217771 2.2.2. 2777777 — к HILL MELIA AI, 22220272 Z ELLES LE И КЕЕДЕ TAATA АНААН АН TAS ОООО HIERHER 2 777; 7777777477777/2222722F2222177F2727Z27 TABLA MIU P AE. (22227272221222222722 A RADO OT, LEE Z27775 sss E IIIA AI EV TARTA TT COTATI КЕТҮ A = == x 2 == N = “ RATITO RI TS IAN TIRO VE er 222772777274 "re = s — O í y 4. LER REGERE EY KERR IOS 222142544 24722041 Fig.3. Diagrammatic section showing the sudden change from arenaceous to argillaceous beds, between wells 159 and 161. As will be seen from this diagram, there is near the right a bed of | about 1o to 15 feet of reddish soft sandstone (1) exhibiting two sets of ( 124) YENANGYOUNG, 79 joints, This is followed by about 6 to 8 feet of well stratified bluish clay (2) which forms the surface, and is quite conformable to the sandstone. The sandstone terminates suddenly, and is replaced in the same level by bedded clay; higher up the sandstone continues some distance further, but it soon disappears entirely, and near the left of the section nothing but a bed of well stratified clay is seen. From these few instances it will be seen how utterly impossible itis to identify correctly the different beds recorded in the deep wells. This is, however, not the only difficulty which impedes a correct interpretation of the boring registers. There are two more of no small importance, 272., contemporaneous erosion and consequent local unconformities within the series of the petroliferous beds. The best instance of these two features is shown in a section in the Aungban- yo just below the drilled well No. 38 which is reproduced on plate IX, and the most interesting part of which has been constructed on the base of very careful measurements in the following diagram. T sS SS SES RUN | š S SSS “Ц МИИ QA SSS = D 2 = СЕЗ TI zu. Bi Fig. 4. Diagrammatic section showing double unconformity above the first oil sand in the Aungbanyo. colour slightly tinged reddish (1). The bedding of this sandstone is to all appearances perfectly horizontal, a feature which is rendered | very conspicuous by thin partings of greenish clay. A bed (2), of A about 4feet in thickness, rests unconformably on this sandstone, “y | ( 125 ) The series begins with a fine, rather hard, sandstone of Bi “ 8o NOETLING : PETROLEUM IN BURMA, formed by an alternation of thin, extremely regular beds of clay, and ` somewhat thicker beds of sandstone, none of the layers exceeding а few inches in thickness. These beds form an angle of 1119 with the beds of the lower sandstone (1). zu It is followed by a series, about 40 feet in thickness, a alternat- ing beds of sandstone and clay, being again apparently horizontal; it begins with a layer f sandstone (3), similar in appearance to bed (1), which is followed by bands of very hard sandstone (4) and bluish | clay (5), each of which successively overlap the lower beds. This section proves in my opinion two points, 222. : (a) A contemporaneous erosion. (0) A double unconformity.» Another instance of contemporaneous erosion is illustrated in figure 7, although it is here not so distinctly seen as in the former, being affected by some features presently to be mentioned. It may be fairly supposed that within the petroliferous sands similar features often occur. In fact, I believe, that bed (r) in the- above diagram represents either the first or the second oil sand, and | that as a consequence their importance as a receptacle of the petro- leum has been affected. On the other hand we see that under such circumstances it/is almost impossible to correlate the petroliferous sands throughout tle oil field, if we have no other feature to guide us than the petroleum which they contain. (6) Veins of eruptive mud.—It is one of the strange features of the Yenangyoung oil field, that although the strata were subject to fold- ing, that this has not led to dislocations worth speaking of. There is, of course, a certain amount of faulting, but the biggest throw which I have observed amounts to lessthan 50 feet, and even this is not quite clear. If any dislocations have taken place, they generally do not exceed a few feet, and remain quite local. On the other hand 1 The word unconformity is here used in a different aud less signilicant sense than is usual in English Manuals of Geology.—Ed. ( 126 ) ' ETE | ah" "T - Rn D Ond NETS ja mE = * ч es y. = VENANGYOUNG, 8r res intersect the strata without, in most instances, producing Iting. The diagram and plates exhibit numerous instances of ies of beds being intersected by a fissure, without otherwise | aps iod be it, Diagram fig. 7 orda a very good илсе үп colour. | They аге generally very hard and stand out in the | E a reef from the Jae di softer strata. So far they afford mixed with a few hard concretions ; the whole mass was ntly horizontally spread out, At first I felt inclined to interpret cious clay is exposed to the action of waves. When surveying juthern part of the oil field, however, the true explanation was ice found; these beds represent nothing else but true eruptive ее (сшщ these s duet beds of ne үг it d 4 ( 127 ) в: is a good deal of fissuring, particularly towards Beme, but the 82 NOETLING : PETROLEUM IN BURMA, the following diagram. We see here a series of perpendicular o£ ni l M Fig. s. Diagrammatic section showing the intersection of perpendicular, horizontal and diagonal veins of eruptive mud ¡in miocene sandstone, Taungle-yo, east of Beme village. i highly inclined veins which intersect a fine soft sandstone, filled with clay, or rather fine mud. The structure of the material proves clearly that it must have been forced up into the fissures, completely filling them. The mud consists of a mass of fragments of sometimes well stratified clay, wbich are arranged in lines roughly parallel to the walls of the vein, It is quite evident that the surface of these clay fragments must have been moist and in a more or less soft state, thus allowing them to be compressed into a homogeneous mass, while still preserving their individuality in the core. If the expres- 4 sion may be allowed, these mud veins exhibit a porphyritic structure, Frequently hard concretions are imbedded, like (a) in figure 5. For a certain distance from either side of the walls the mud is usually | more or less impregnated with a whitish alkaline substance. In the above section the perpendicular veins intersect horizontal 3 ones of the same structure, and in one instance at least it is quite а clear that they must һауе passed through the horizontal beds a producing sometimes'a small dislocation. In the majority of the | cases the substance of the horizontal and vertical veins has been so intimately anchylosed that it appears as if the horizontal beds were ( 1239 53 “ YENANGYOUNG. 83 continuations of the vertical veins, injected into the surrounding beds. There is no doubt with regard to this mode of occurrence at another section, but in this particular instance it is quite clear that the horizontal beds (5) existed before the vertical veins (v) passed through them. As to the shape of the veins themselves there is hot much to be said; they apparently represent a network of fissures varying from the thickness of a sheet of paper to about ten inches. The veins . remain sometimes independent, two or more may join, or lateral offshoots may branch off and continue to run as independent veins, Another and perhaps better illustration of this feature is the occurrence of mud veins near well No. 510 in the Beme part of the Yenangyoung oilfield represented in the. following woodcut. We see here an almost horizontal bed of eruptive mud (4) imbedded in Fig. б. · Diagrammatic section showing diagonal veins of eruptive mud in miocene sandstone, near well 310. soft, horizontally stratified sandstone. This mud deposit sends off several offshoots, of which (2) may perhaps be doubtful, whilst (c), (4), and (e) are good examples of such veins. The offshoots (г) аге particularly interesting, as they exactly resemble the apophyses of an intrusive rock and are unquestionably injected into the surround- ing matrix, | The most interesting offshoot is however (7). It branches off the main vein at about 70°, keeps to that direction for about 3 feet, then suddenly forms a knee, and follows the bedding of the sandstone, Ga | ( 129 ) 84 NOETLING: PETROLEUM IN BURMA, sending oft a short apophysis in the opposite direction; it remains quite conformable to the bedding of the sandstone for about 3 feet then turns up again, passes into a higher level, where it again fol- lows the direction of the bedding for some distance and then traverses | the sandstone to the surface. About 33 feet from the point where (d) originally branched off from (a) both are joined by a vein of only 2 inches in diameter which shoots off at an almost right angle from (a) and joins (7) about 8 feet above (a). It is not quite certain whether the branch (0) is also a diagonal offshoot of (а), or whether it is an in- dependent vein, merely traversing (4); its continuation towards a lower level seems to indicate the former, but this may also be merely an apophysis like (c) only somewhat stronger. However, whether independent or not, this does not in any way affect the structural importance of the veins here described. It may be remarked that this section was exposed at one side of the deeply cut road leading to well No. 510, whilst no signs of the veins were exhibited on the opposite side of the road. | The mud with which the veins are filled exhibits its usual lumpy structure. It may be remarked that at one part of (4) it contains so much of alkaline salt, that its appearance is very similar to the gypsum veins. | Fig. 7. Diagrammatic section showing unconformity and horizontal veins of eruptive mud in upper miocene sandstone, near wells Nos. 530 and 541. Another very illustrative section, represented in figure 7, is seen near wells No. 530 and 541 in the same part of the oil field. In a ( 130 ) YENANGYOUNG, 85 series of fine hard sandy beds alternating with beds of sedimentary Е Íptive mud ; higher above another bed (3) which, ОРИ E the unconformity above it, unquestionably represents the termination of a bed of eruptive mud. This is followed by a series of rather hard " Ж | sandstones, alternating with thin beds of clay, into which is injected zB ‚ horizontal vein of eruptive mud. Т could easily increase the number of instances, but they all | 1strate the same features; perhaps I might mention a large r p of sandstone, which had apparently been crushed, and its ments recemented by the eruptive mud which filed the k: , but this only represents on a smaller scale what is already wn in plate VIII. | Me find beds which thus exhibit all the characters of eruptive saca: in the regular sequence of the strata, is most probable that eruptions of liquid mud took place during конон of the strata between which we find the mud streams V m place during the formation of the upper ênê and ably also of the lower Yenangyoung stages. This mud spread horizontal layers and was thus inclosed in the regular series. Eble fissures, through which mud was 5 pressed up, passing gh Pe original horizontal layers. E and also in the lower Yenangyoung stages. So far 1 one were noticed in the upper parts of the Yenangyoung stage, while itis certain that they do not occur in the Irawadi series. от This seems to me of a great theoretical importance, to which I shall revert ina subsequent chapter; but it may be mentioned here that % up to now I PE only observed these veins within the Yenang- | yo ung oil field. E | Me ( 131 ) i v. 86 NOETLING : PETROLEUM IN BURMA. The anticlinal and dome-like structure.—The late Dr. Oldham, when visiting Yenangyoung in 1855 had already noticed that the oil fields were situated on the crest of an anticlinal flexure ; he simply ` mentions the fact, without any further theorizing. In 1888 I was able to fully confirm Dr, Oldham's observations and to give some details with regard to the structure of the anticlinal arch. After the topo- graphical survey had given the basis for a trustworthy geological map; a new structural feature was discovered. The peculiar mode of outcrop. of the zone of Hzppotherium antelopinum, proved that it was not only a simple anticlinal arch, but that the general struc- ture of the Yenangyoung oil field was that of a low dome or “ turtle- back ” fold. aa, The anticlinal arch.—' The anticlinal arch formed by the tertiary strata at Yenangyoung is comparatively flat and broad, in consequence of the low angle of dip of the strata; nowhere does this exceed 40°, and even such a high angle has only once been noticed on the eastern side of the anticline. The angle of dip de- creases towards the centre of the anticline, In passing over the arch from west towards east we see the angle of dip of 37? to 38? on the bank of the river gradually becoming flatter till the axis of the anticline is reached, where the strata appear horizontal for a short distance ; after which the angle of dip again gradually increases till it reaches its maximum of 39? to 40%, which it keeps on as far as I have examined the country. ` p m The anticlinal arch appears therefore almost symmetrical, but it is quite certain that it dips slightly steeper towards the eastern side. + The direction of dip is very regular and generally south-west on the western and north-east on the eastern side, It varies slightly of course, and its magnetic bearing may be said to oscillate be- tween 60? to 68? west of south or east of north. Necessarily the direction of the strike varies also, and its diree- tion ranges from 325? to 330, but within this не: 1t keeps the direction very steadily. ( 532 ) YENANGYOUNG, 87 bb. The longitudinal arch.—1 understand under this term the low arch which is formed by the strata in the direction of the - axis of the anticlinal. As already stated, its presence was first discovered after mapping the Yenangyoung oil field ; the presence of such a dome shaped anticlinal was made apparent only after mapping the outcrop of the zone of Hzppotherium antelopinum. This zone forms a well marked horizon in the sequence of the strata, and crops out in the shape of an elongated ellipse, the long axis of which measures two and a quarter miles, while the short (transverse) axis amounts to slightly over a mile only. It was desirable that the view thus theoretically obtained should be confirmed by actual observations, if possible. It is of course obvious that observations of this kind require the greatest care,—in fact to be of апу value, they could be only carried out strictly along the axis of the anticline; but even then it will be seen that, from what I have said above with regard to local unconformities and the inconstancy of the beds in horizontal direction (see page 78), fhe possibilities are that the natural dip of the longitudinal arch may be obscured by these features, and at any rate great difficulties were to be expected in ascertaining facts with regard to its exist- ence. However, I carefully examined the Yenangyoung oil tract, specially with regard to the longitudinal arch, and the following are the observations which I have made. South of Beme, particularly along the Maung Aung Gyaw The-Yo, and to the north of well No. I, the beds exhibit a distinctly southerly dip along the longitudinal axis of the anticline, which, however, and this is the remarkable part of it, seems to be limited to a certain restricted area, north, south and west of which the strata exhibit their regular western dip. In this case it is not quite certain whether this southern dip is not due toa local sliding of at least a part of the upper beds on the soft clay below ; it may also be that the southern dip indicates the presence of another structure presently described as intersecting folds. The ground however was not favourable for further examinations, neither (“rag .) eg: U “SEAS SPSS A) ÓN E Ш К E TOS =" t ٤ 88 NOETLING : PETROLEUM IN BURMA, was it in the Beme or Kodoung oil tract, owing to the direction of the ravines. | More favourable was the direction of the Ayatpo-yo, at the southern part of the Yenangyoung oil field andthe adjoining slopes of the Aungban-yo. The Ayatpo-yo cuts the petroliferous area. in an almost longitudinal direction, and it was therefore expected that if any dip either in northern or southern direction did exist, it would show here. x The view plate VIII, will distinctly show that the bluish shales exhibit a most marked inclination of about 7 to 8° towards north, an observation. which has also been confirmed at the southern part of the Twingon oil field, where the same bed comes to the surface. The same inclination is followed by the lower beds of the Yenang- young stage, although much of it is counteracted higher up by the irregularity of thickness of some ofthe beds, Buton the whole a most distinct northern inclination was noticeable, | On the northern slope of the Aung-ban-yo it seemed as if there was a slight southern inclination, although this could not be ascer- tained owing to the beds not being well exposed. Towards the northern end of the Twingon tract a northern dip was observed, but in this case itis not quite clear whether this is not due to an altogether different structural feature presently to be described. | | š It is on the other hand quite certain that, further towards north near the Pin-choung, the surface of the zone of Hippotherium anti- lopinum exhibits the most distinct northern dip. Although very scanty, these few observations are sufficient to support ina great measure the theoretically deduced view of the existence of the longitudinal arch. In the southern part of the field, where a southerly dip is required, we notice a southerly dip, and in the northern part, where a northern dip is required, we notice | a most distinct northern inclination which. could not entirely be hidden by the irregularities of the sedimentation, We may therefore assume that it is unquestionably proved Ge 154. ) YENANGYOUNG, 89 3 Кы. like жый АА, but before attempting to explain the forma- tion of this feature, it will be useful to describe the sections as E е2 оп the surface and then to discuss the sections from the a 4% Ee Ere E 24 8 E E. %) g я B.—The Superficial sections. M 146) In order to get ata fair idea cf the transverse structure of the E. and their structural features. It will be seen that the vadi series and Yenangyoung stage are chiefly exposed, while e topmost part of the Prome stage is only seen along a short distance in three of the sections. Although not much can be said ho нв sme are the top Бе of the сее pev E. Passing the centre of the anticlinal the zone is again met with, ` but now it Жер towards east, followed by the Irawadi series, dipping at about 2$" „alte ? à | c Dr ES ( 135 ) 90 NOETLING : PETROLEUM IN BURMA, SECTION No. 6 (PL. XIV) ALONG THE POUNGKA-DAW AND NATSIN RAVINES; NORTHERN END OF THE YENANGYOUNG OIL FIELD. On the western side of the anticlinal, the zone of Hippotherium antilopinum is found at 1,716 feet from the boundary of the map and from here to the point where it is again seen on the eastern side is a distance of 5,100 feet where the beds of the Yenang- young stage may be seen, and right in the centre a bluish grey bed is exposed, which must be considered to represent the Prome stage. SECTION No. 5 (PL. XIV) ALONG THE AUNGBAN-YO (SOUTHERN SIDE OF THE TWINGON RESERVE). This section is of interest, because the upper Prome stage apparently rises here highest above sea level, occupying in the shape of bluish grey shales and sandstones, about 1,320 feet in a horizontal line, near the centre of the anticline. SECTION No.4 (PL. XV) ALONG THE NORTHERN BRANCH OF THE BEMECHOUNG (KHUNNHITSE-YO). It is quite evident that in this section the level of the top of the Prome stage is less elevated above sea level than in the former section, while the Yenangyoung stage shows no decrease of its superficial exposure. SECTION No. 3 (PL. XV) ALONG THE SOUTHERN BRANCH OF THE . BEMECHOUNG (TOUNGLE-YO). The top bed of the Prome stage is here still exposed in the central part, but it wili be noticed that the distance between the zone of Hippotherium antilopinum on either side of the anticlinal has decreased to about 4,400 feet. SECTION NO. 2 (PL. XV) ACROSS MINLINDOUNG TO YEDWIN- AING-YO. In this section the Prome stage has entirely disappeared; the ` Yenangyoung stage is badly exposed in the centre, but we see ` that the zone of Hippotherium antilopinum forms a continuous | layer interrupted by erosion at two localities only, stretching ( 336 ) YENANGYOUNG, 91 from west along the slopes of Minlindoung towards the east, covered by beds of the Irawadi series. The dip on the western side is about 30°, but it becomes flatter and flatter towards the centre forming the reverse on the eastern side. These sections prove conclusively that the angle of the arch of the anticlinal changes in proceeding from the south towards north; it is very flat near Minlindoung, but becomes more and more com- pressed towards the middle of the oil field, whence it again slowly flattens out. The natural consequence of this change in the arch of the anticlinal must be a rise of the crest from its southern end towards the centre and a fall from thence towards its northern end. The lateral pressure which has produced the anticlinal did not act equally throughout its length аё some places it acted more forcibly, at others with less energy. At the former places the beds were more compressed than at the latter, and naturally deeper strata were raised closer to the surface than it was the case at places of smaller energy in the lateral pressure. The natural result of this different energy must be the production of a dome or turtleback-like elevation, the slope of the surface of which is directly proportional to the energy of the lateral pressure. C.—The sections of the drilled wells. | From the records of strata, as found in the deep wells, as I received them from the boring engineers, I have constructed the sections on plates XIII, XIV, making allowances for the level of each well, LÀ in order to obtain as accurate a position of each bed above sea level as possible. A few words must, however, be said about the great difficulties in the way of comparing these boring registers, wben there were no other means of identifying and correlating certain beds but such vague terms as have been used by the drillers, and the depth at which such beds were found from the surface. It is also almost certain that the various drillers have used slightly different terms to designate the lithological character of one and the same bed, a discrepancy which of course increased the difficul- ties still more. (1:37 ) 92 NOETLING: PETROLEUM IN BURMA. А glance at the boring registers shows how almost hopeless itis to introduce order into this confused mass of details. The chief difficulty is due to the similarity of the strata met with. There is no lithological difference between two samples of clay, the one coming from near the surface, the other from, say, 1,000 feet depth, and the same remark applies to the arenaceous beds. No fossils having been found in any of the beds, we are therefore unable to identify the strata found in different wells. The task is rendered the more difficult, because certain features, which will be dealt with in a subsequent chapter, indicate a very peculiar structure of the Yenang- young oilfield. If we further consider that the vague terms which the drillers used to designate the beds, such as “ shale,” “slate ” and “clay,” may in one case all mean one and the same argillaceous bed, while in other cases they really represent lithological differences, it is obvious that a fairly accurate identification of the strata found at different places by different men and at different times, recorded in varying terms, is almost hopeless. After carefully comparing the above records one feature was, however, very conspicuous ; imme- diately above the sand which chiefly produces the oil there is a bed of clunchy clay which seems of particular tenacity. The fact was also established that within certain limits this bed occupies a remarkably constant position above sea level. Thus an important horizon has been established, the beds above and below which can be considered separately. I must mention, however, that in some cases the identification of this bed is not absolutely certain, and the boring records may therefore be interpreted in a way different from the one I have suggested in the sections constructed on the strength of the boring registers. I do not think, however, that this will materially affect the theoretical conclusions deduced therefrom. i It is extremely difficult to say whether the beds thus distinguished, and succeeding each other vertically, represent true geological horizons or not. In fact there is sufficient evidence to believe that ( 138 ) YENANGYOUNG. 93 some of the minor beds represent but local horizons within the stratigraphical series. With the above restrictions I have adopted the following sequence of strata: (a) Immediately below the Yenangyoung stage follows a thin bed of blue clay which apparently represents the upper portion of the Prome stage. So far this bed has only been found in well No, 55. It is extremely difficult to say whether this bed is also represented in such wells as Nos, 3, 8 or 36, where a sequence of very thin beds of clay alternating with sandstone has been found imme- diately below the Yenangyoung stage which is usually designated as “shale.” The probability is decidedly in favour of this view. (5) Below the above bed follows the first oil-sand, which contains only traces of oilin wells Nos. A and 21, in all the other wells it is either dry or carries water. The first oil-sand, however, may in its turn follow immediately below the Yenangyoung stage, without the separating medium of clay (а) being present. Instances have been recorded in various wells; as No. A, No. 40, etc, It is impossible to say whether in such instances as well No. 3 or No. 25 the *slate and sand ” immediately below the Yenangyoung stage represents the first oil-sand; it is, however, highly probable, because, in the quoted instances, they have been discovered in the same position as the first sand in other wells. (c) The first sand is usually followed by a bed of Те of varying thickness; it is very probable that the first two beds are occasion- ally absent, and that this bed follows immediately below the Yenang- young stage; at least some of the boring registers cannot be inter- preted in any other way. (d) The second oil-sand follows, as a rule, below the above men- tioned clay, but, as in the case of the above mentioned beds, there are instances whichrenderit very probable that the upper strata are entirely absent, and that the second oil-sand follows immediately below the Yenangyoung stage. Inthicknessit varies a good deal and the record of No. 68 suggests the idea that in this instance the separating ( 139 ) 94 NOETLING: PETROLEUM IN BURMA, | | clay (с) 1s absent, the first and second sand thus forming a continuous series, Nowhere within the Kodoung area, except well No. 21, is oil found in this sand; it is usually dry, but sometimes yields a good deal of water, It is possible that on the eastern side of Kodoung this bed is represented, as for instance in No. 3, by a series of thiñ alternating beds of clay and sandstone which are usually termed shales, (e) Below this bed follows a remarkable stratum of darkish blue very tenacious clay, apparently without the slightest admixture of sand. This bedis a very constant one and has been found in all the wells where it caps the petroliferous sands. In thickness it varies ` very much and it is quite certain that in some instances like Nos. 11, 60, etc., it forms together with (a) and (2) clay, to the entire exclu- sion of the 1st and 2nd sand, an argillaceous layer of consider- able thickness, | (f) The third oil-sand has been found in all wells, but to judge from the boring registers it must vary a good deal in thickness. It contains petroleum in a considerable quantity in all wells except Nos. 64 and 68 at Kodoung and Nos. I, V and VII. lt is remarkable that in some instances the upper part of the third sand contained water which was followed by oil, for instance well No. 61; in others, like No. 36, the petroliferous layer was of small thickness, and was followed by a thick water bearing layer. Wells No. A and No. 6 have such a remarkable boring record, that, provided they are correct, we are bound to suppose that by the intercalation of an argillaceous layer (e') the part (/") containing a considerable quantity of petroleum, has been separated from the 3rd oil sand. It is only in the above two instances that this feature has been noticed, and as these two wells belong to the earlier wells, when no special care was taken with regard to the boring register, it is quite possible that some error has crept in, in fact it is almost certain that the boring register of well No. 6 must be incorrect, because, as it stands, it hardly fits in with the adjoining wells. - ( 140 ) YENANGYOUNG, 95 (e) In all wells in which the drill passed through the third oil- sand, a bed of clay has been found immediately underneath it, which lithologically does not differ from any of the other clay beds. (2) Below the above layer of clay occurs a thick stratum of arenace- ous beds which forms the fourth oil-sand. It has been found in wells . Nos. 40, 13, 51, 54 and 57. This sand does not always contain petroleum ; in some instances like No. 54 it is water bearing at the top, dry in the middle and petroliferous at the base, it is apparently divided by some minor parting of clay in No. 51, while itis almost certain that it forms a continuous layer together with the third oil- sand in wells Nos. 59 and 60. (z) There are only a few wells which have passed through the 4th sand, but there are proofs that it is followed by a comparatively thin bed of bluish clay. Below this bed follows in well No. 54 a series of sandy layers one of which is petroliferous (Z), separated by argillaceous partings. Whether these strata represent proper horizons, or whether we have to consider the series as a thick argillaceous bed subdivided by sandy layers, remains to be seen, I have constructed the sections on plate XII, with reference to the above remarks about the sequence of the beds found in the petroli- ferous series. How far my views expressed in this way, are correct remains to be seen. [t is quite possible that, owing to the great similarity of the lithological character of the beds, errors have not been avoided in the correlation of some of the beds, but I believe that the main outlines of the sequence will be found to be correct. As the wells are never situated in exactly straight lines, I have drawn across the area of the Kodoung field a series of transverse lines, connecting the greatest number of wells by a straight: line, whilst others which did not exactly come within this line were included when they were not too far off. In this manner I obtained a series of cross sections which are shown on plate XIL A com- parison of these transverse sections with each other, shows how hopeless it is to unravel the detailed structure of the Yenangyoung Coup ) MEE CU LL сқ сы 96 NOETLING: PETROLEUM IN BURMA. oil field. None of these cross sections quite correspond with each other. Of course a general sort of agreement may be made out, but the more I have studied and compared them, the more difficult it seemed to explain their unusual features. The most conspicuous instance is shown in section V, between wells No. 1gand No, rrand No. to. In No. 19 immediately below the lowest bed of the Yenangyoung stage there is a bed of sand of 130 feet in thickness followed by the clay (e); in No. 11 immediately below the same bed a stratum of clay of 201 feet in thickness has been found, followed by a thin bed of sand containing petroleum below which follows clay (г) ; іп No. то, there is a bed of sand of 212 feet thick- ness immediately below the beds of the Yenangyoung stage separa- ted from the oil-sand by a bed of 63 feet thickness of clay, noticed in the two other bore holes. Now itis quite evident that such a re- markable disappearance or thinning out of beds of nearly 200 feet in thickness within such a short distance would be rather ano- malous, even if we admitthat such rapid and sudden changes in the lithological character of the beds do take place within the same level. In fact the problem of the discrepancy ofthe various sections puzzled me so much, that I considered it an almost hopeless task to obtain a clear idea about the structural features of the oil field; I almost felt inclined to assume that serious blunders must bave been committed in recording the beds through which the borings were made, The study of Professor Orton's ingenious paper on the occurrence of petroleum in Ohio, suggested an explanation ; he- observed the remarkable fact that the successful wells were always on the domes while the dry wells were situated in sinks or depres- sions of the anticline.! The idea suggested itself to classify the wells of the Kodoung 1 Geological Survey of Ohio, vol. VI., 1888, Do. 3rd organization, vol. L, 1890. The Trenton limestone as a source of petroleum and inflammable gas in Ohio and Indiana, U. S. Geological Survey, 8th Annual Report. елда) , i و ت‎ E YENANGYOUNG. 97 tract (which, as we have seen, draw their oil nearly all from one and the same bed, the 3rd oil-sand) into three classes: poor wells below . 500 gallons а day, better ones yielding between 500 and 1,500 gallons a day, and rich wells which yield more than 1,500 gallons a day. On entering these observations on the map, plate XV, not much seemed to be gained by this, rich and poor wells appeared to be distributed in a most erratic way, only the well known fact that in the Yenan- gyoung oil field a very rich and a very poor well may occur close together appeared to receive further support. Note, for instance, the case of wells No. 53 and No. o, the former being a rich and . the latter a poor well, although their horizontal distance is barely 180 feet. But when the wells of each single class were connected by lines, a most curious feature was almost at once noticed. The | lines connecting each class did not run straight or in a slightly curved way, but they were arranged in a zig-zag course. “Тһе following willdemonstrate this; wells Nos. 25, 27, 28, 26, 48, 55, 42, 35 are all rich wells, connecting these wells by an uninter- rupted line, wells Nos. 25, 27, and 28 were situated on an almost straight bearing; at No. 28 the line took a sharp turn ‘inwards, so to speak, and wells Nos. 28, 26 and 48 were again found to be situated on an almost straight line, the above named five, wells were therefore situated on both sides of a very acute angle, at the apex of which was well No. 28; proceeding further from No. 48 towards Nos. 55, 32 and 35, these were again situated in an almost straight line, meeting the line 28, 26, 48 ata very acute angle, but running almost parallel to line 28, 27, 25. . So far this may be accidental only, but, luckily enough, a few ‘more wells of the middle and poor class, proved almost to a certainty, that the explanation of these lines must be something more than a mere accident. On connecting the middle class wells Nos. 58, 30 and 31 by a line, it was found that they too were situated on a rather acute angle, well No. 30 at its apex and wells Nos. 31 and 58 on its sides, and that line 58, 30 was almost parallel to line 25, H ( 143 ) 98 қ NOETLING: PETROLEUM ІМ BURMA. 27, 28, while line 30, 31, seemed to conform in its direction to that of wells 28, 26, 48. | How far the short line connecting wells Nos. 20, 62 and 67 con- formed to these lines connecting the middle class wells was not quite clear, but another equally conspicuous instance suggested itself almost at once. Оп connecting the poor wells Nos. 14, 12, 15, it was. found that these also were situated on an acute angle having its apex directed towards east. Wells Nos. 15 and 17 could not be connected | by a straight line because the indifferent well No. 16 intervened which together with 17 and 15 is situated along an almost straight line. A line connecting the poor wells Nos. 17 and 15 must therefore pass to the west of well No. 16, and on following this clue another segment ofa zig-zag line was exhibited, turning one point towards east, the other towards west. Now on crossing over to the eastern side of the petroliferous area, and connecting the poor wells Nos, 3, 8, 23 and 9, it was at once noticed, that wells Nos. 3, 8, 23 formed a very acute angle turning its apex, whithis formed by well No. 8, towards west, while wells Nos. 8, 23, and 0 formed another acute angle, having 23 at its apex, but turned towards east. It is remarkable that the line 15, 12, 14 on the west side and line $, 23,9 on the east side are directed in the same way, that is to say, they have the apex turned towards east, and that inside the narrow band of land thus defined, there were the rich wells Nos. 7, 53, 43 and 13. Another remarkable case was noted with regard to the in- different wells Nos, 6, 10, and 4 and the poor well No, 5, No. A and No. 1; the first three are ranged in a line which forms an acute angle having its apex turned towards west, butinside this protruded the sharp angle A, 5, І, in such a way that its apex, well No. 5, was almost directly between wells Nos, 6 and 4, being approximately not more than 200 feet from either, | It is needless to go into any further details, which can be easily ascertained by an inspection of the map; it is sufficient to say that Съм 0 YENANGYOUNG. | 99 'the instances here mentioned rendered it almost beyond doubt that the wells are distributed along a zig-zag line, which follows a certain system. ! The cue thus given has been followed up, and when not proved by the actual situation of a well, the direction of the lines was supposed to run parallel to another one already proved. In this way the map, plate XI, was constructed, and it is at once clear, that there must be a certain rule with regard to the situation of wells producing more oil than others. It will be seen that in thus connecting the wells of each class, by lines, each class is situated within a certain welldefined area to the total exclusion of all the wells of other classes. We notice that the richest wells form a rather narrow belt in the centre, this is surrounded by a broader belt of indifferent wells, and the latter is again surrounded by a belt of wells yielding only a small quantity of oil. Before proceeding any further I must at once explain that I do not by any means believe that the lines as laid down on this map represent actual boundary lines, the strip of rich wells may be a little broader than depicted, but it is clear that it cannot extend beyond theline connecting the indifferent wells, and the same of course applies to the latter with regard to the poor wells; they cannot possibly extend beyond this line. Though it may be quite possible that, with the advance of our knowledge of the structure of the oil field, the lines will be perhaps somewhat modi- fied, the main features will probably remain. The belts, it will be seen, run in a very curious zig-zag manner, and it is quite evident that whenever we find an indentation on the one side, it corresponds to a projection at the opposite one. Another feature is also remarkable; it seems that the Kodoung petroliferous area is separated from the Twingon field by a band containing only a small quantity of oil, and that the tail end, so to speak, of the Twingon belt indents the Kodoung belt just at its north-eastern corner, as apparently indicated by the indifferent wells H 2 ( 145 ) 100 NOETLING : PETROLEUM IN BURMA. Nos. 36 and 46 and the rich well No. 39. However, this feature cannot be followed up for the present, nor is it possible to say whether there exists a similar regularity in the distribution of the Twingon wells, because the latter do not draw their oil from one and the same level like the Kodoung wells. For the present we must therefore content ourselves with the study of the Kodoung tract, It seems that it begins with an irregular elliptical area close to the Aung-ban ravine and continues in the shape of a comparatively | narrow belt, the broadest extension of which between wells Nos. 52 and 67 does not exceed 2,500 feet in a straight line, while its minimum "breadth is reduced to about 600 feet between wells Nos. 9 and 12, towards Beme, where it apparently again terminates in a similar irre- gular elliptical area, The total length of this belt will hardly exceed 5,000 feet, and it is quite evident that its general axis forms an angle with the general direction of the strike of the strata deviating to- wards west from the former or having a north-west bearing. Within its two terminations the belt forms a series of zig-zags already mentioned, just as if it were folded by a pressure acting in the direction of the main axis. Now the question obviously suggested itself. What relations do these curious zig-zag lines bear to the geological structure? If Orton's theory with regard to the distribution of oil in the strata is correct, vi2., that the richest wells are always situated on elevations, while sinks or sags generally prove to be dry,! then it is possible that the belt indicated by the rich wells marks the crest of a fold running in a zig-zag direction and that the indentations represent the sinks or sags? And further, if so, what structural conditions would answer to the first presumption? Supposing that the lines, as depicted on the map, represent a rough sort of contour lines, the only structure which could be imagined would be a series of roughly parallel folds which bifurcate, and are linked together in such a manner, that the branch of one fork opening in one direction also forms a branch of the next 1 Orton, Geol. Surv, of Ohio, vol. I. p. 9o, ( 146 ) YENANGYOUNG. 101 fold, but opening in exactly the opposite direction, The following diagram will demonstrate this sort of structure. =. | == Fig.8. Diagram showing arrangement of the intersecting folds in the Kodoung petroliferous tract. : The line marked (a) would represent a zig-zag ridge, running exactly as the oil belt does, sending off lateral branches (5) separated by hollows B. Let us for the moment disregard the question of the origin of such a peculiar structure, which will be dealt with later on and, as- suming it to exist, shall have to endeavour to show that this structure originated at the time of deposit of the petroliferous strata, which view I trust I shall be able to prove. As regards the physical conditions of the folds it is by no means necessary that the crest of the central ridge should retain the same level throughout, in fact it is most probable that it would not, and that its height would vary ; at the same time it is by no means necessary that the lateral branches (2) should all be of the same length, they will probably vary very much, and it is also very probable that they eventually flattened out and entirely disappeared. | Now let us consider the nature of the deposits formed under the above conditions; it is very probable that these may have been entirely different on both sides, on one side sandy beds were depo= sited, while on the other argillaceous beds were formed ; at the same time owing to the oscillation of the central crest a communication ( 5147) u 102 NOETLING : PETROLEUM IN BURMA, may have existed between B and В’ while there was none between B' and B", beds in B and B' may therefore exhibit a certain similarity; while there is a vast difference between the physical nature of the beds in B' and B". It is also very probable, that towards the heads of the basins, where they were sufficiently separated, the sequence of the series varied considerably in adjoining basins, while further towards the end where the separating ridge (4) becomes lower the beds join and assume a more uniform character. It will be seen that the above theory will allow for an enormous variety of details in the deposit, which can be multiplied to any degree if we take into account the contemporaneous erosion, which has been repeatedly proved. Now I must confess, that when looked at from the points of view of this theory the sections of the deep boring appeared in quite a new light. Certain anomalies, as for instance in section V, the rapid change of a bed of clay of 201 feet thickness in No. 11, into a sandy layer of 212 feet thickness in No. 10, were easily explained by the above theory ; No. 11 is situated at one and No. то at the other side of the central basin, hence the difference of the physical nature of the sediments within so short a compass. We are, however, in a position to test the correctness of the above theory by the comparison of the boring registers, but then we must at once dispose with the orthodox method of simple sections across the strike, and we will have to arrange the sections in such a way as required by the above theory, that is to say, quite irrespective of the present direction of dip and strike. It is one postulate of the above theory that the rich wells m. to be situated along the direction of the central ridge and not on its lateral off-shoots, occupying generally the highest points. We should therefore observe a rise of the petroliferous beds, from the wells of lower production towards those of the higher. Another postulate would be that within the area supposed to be x occupied by the basins we should observe a slope of the beds towards the centre of such basins. ( 148 ) үү? YENANGYOUNG. 103 To prove these postulates absolutely a much larger number of borings would be required; as may be seen from the map, at most ` places the lines are purely conjectural, and frequently the crucial points are wanting in order to complete a given section. However, there is still sufficient information contained i In the boring registers to strongly support my theory. A most favourable part is the northern end of thé oil tract, although there are unfortunately some four or five wells the boring records of which are missing although they would be óf the utmost importance. As shown on the map the rich well No. 47 is surrounded on all sides by a series of indifferent wells Nos. 11, ro, 20, 21,6 and 10; and these again are surrounded by an irregular circle of poor wells Nos, 66,64, 2, A, 5. The theory therefore requires that the petrolifer- ous bed of No. 47 should represent the highest point, and that from thence it should slope in every direction, excepting of course that which forms the continuation of the central ridge. These borings are numerous enough to allow of three sections being constructed; one in south-south-east and north-north-west direc- tion, in fact, it is almost along a north to south line connecting wells Nos. 11, 47, 21. The second in an east and west direction, connecting wells Nos. 64(2) 20, 47, 10, and thence proceeding further towards wells Nos. 8, 7 and 9. The third in a south-west to north-eastern direction, connecting wells Nos. 19, 47, 6, A, and 36. (a) Section XX, pl. XIII, wells Nos. 11, 47, 21. The section in well No. 11 affords a very curious instance of a large development of argillaceous beds; aíter 75 feet of strata belonging to the Yenangyoung stage, tbere follow 221: feet of argillaceous beds, below which the petroliferous sand, to the thick- ness of 97 feet, was found resting on water bearing sand. The top of the oil-sand was therefore 170 feet above sea level. | In well No. 47 the section differs already considerably ; Rita of a compact bed of clay, as in No, 11, the argillaceous beds are; separated by a sandy bed of 25. feet thickness containing water at ( 149 ) 104 | NOETLING: PETROLEUM IN BURMA. 220 feet above sea level, and on the top of the clayey beds rests a bed of 50 feet of “blue sand" which must be separated from the overlying beds of the Yenangyoung stage. The petroliferous sand to the extent of 79 feet thickness was found at 274 feet from its surface, and is found 200 feet above sea level, In No. 21, we observe a further change, the sandy bed imme- diately below the Yenangyoung stage, 80 feet thick, contains a small . quantity of oil and unquestionably represents the top sand of No. 47 and overlays an argillaceous bed of 130 feet thickness which exhibits the same feature towards its base as seen in No. 47, that is to say, it becomes sandy, thus probably representing a series of alternating argillaceous and arenaceous beds. The petroliferous sand to.the extent of 42 feet rests on petroliferous sand and was met at the | depth of 290 feet from the surface and its top was 180 feet above sea level. ! | The top of the petroliferous sand was therefore found in— No. 14. No. 47. No. 21. at 170 200 180 feet above sea-level. These figures prove that there must exist a rise of its top from No, 11 towards No. 47 and a fall from No. 47 towards No. 21, (0) Section XIX, pl. XIII, wells 64(2), 20, 47, 10. The series begins in No. 64 (a), below the Yenangyoung stage with a bed.of “blue ”” sand of 30 feet thickness, followed by an argillaceous bed below which 45 feet of ** water sand ” were found followed by 100 feet of clay. The petroliferous sand was struck at 280 feet from the surface or 180 feet above sea level, it is very poor in quality and rests on water sand. In No. 20 the section is not as complete as it might be. Below 62 feet of beds belonging to the Yenangyoung series, 86 feet of “fine soft grey sand with beds of shale" were found ; it is not impossible that the series was sand at the top and clay at the bottom imme- | diately above the thin layer of water sand. The petroliferous sand ( 150 ) YENANGYOUNG. 105 capped by a bed. of clay, was found at 268 feet from the surface or 200 feet above sea level. Well No. 47 has already been discussed, its section above the ` petroliferous sand bears the strongest resemblance to that of the former two wells only that the argillaceous beds predominate, whilein the former the arenaceous beds are thicker. A remarkable change takes place in the sequence of the beds passing from No. 47 to No. 1o, a distance of 460 feet in a straight line. Below the beds of the Yenangyoung series, a series of 162 feet follows, described as “soft grey sand and slate," which rest on 20 feet of inferior oil-sand. It is difficult to find out whether argillaceous beds intervened ; it may be probable, inasmuch as the term “slate” seems to indicate this, but it seems to be almost certain that they were of no importance. I interpret this sequence of strata as the series of thin beds of clay alternating with sand, which is exposed in the Aungban-yo, well developed on the eastern side of the petroliferous tract. The oil- sand was met with at 305 feet from the surface or 147 feet above sea level. Dwelling fora moment on the results of these four wells we note that the top of the petroliferous sand was found in— No. 64 (2) 20 47 10 at 170 200 200 147 feet above sea level. It rises therefore from No. 64 (а) in the direction of 20, keeps on the same level between 20 and 47 and falls rapidly towards Io. (c) Section XVIII, pl. XIII, wells Nos. 19, 47, 6, A, 36. Well No. 19 represents a remarkable set of beds ; immediately below the Yenangyoung series follows a rather thick series of sandy strata with probably argillaceous parting somewhere near the base, although the register is inaccurate in this respect, stating only that soft “grey sand and clay " were found between 95 and 210 feet from the surface, but whatever the thickness of this argillaceous bed may be it is clear that it cannot be great, and that No. 19 is therefore im accord with Nos, 66, 64, 20, 21 as shown by the preponderance of шы 106 NOETLING: PETROLEUM IN BURMA. the sand beds. The top of the petroliferous sand was found at 319 feet from the surface or at 138 feet above sealevel. Well No. 47 has already been discussed. The section of No. 6 is very incomplete, all'that is known is that comparatively close to each other two oil-sands were found, one at 225 feet, the other at 310 feet from the surface, which it is extremely difficult to correlate with those found in different wells. The boring records of Nos. A, 6 and 10 seem to indicate the existence of an oil- sand above the chief oil producing sand which has not been found in any of the other wells. If we suppose the upper sand to be the continuation of the 3rd sand in No. 47, there is a rise in its level from No, 47 towards No. 6; if the lower, then there 1s a fall. The question becomes stil more complicated if we proceed towards A where there are four consecutive sands, the Ist, 3rd and 4th in the sequence being petroliferous, the 2nd dry, and compare these with the adjoining No. 36 where there is only one sandy bed altogether. | | Г H my interpretation is correct and the last arenaceous bed in wells Nos, 6, A and 36, the top of which was found at 160 feet above sea level in No. 6, at 200 feet in No, A, and at 220 feet in No, 36 represents the 3rd oil-sand, then its level falls from 47 towards 6 and rises from there towards A. To me this seems most probable, as it is unquestionably proved by the remarkable run of the line connecting the poor wells Nos, 2, A, 6, r, 41, 40, 3, 8, north of which the two indifferent wells Nos. 46 and 56, and the rich well No. 38, are situated, that a new element in the series stretches from Twingon towards Kodoung, the east end of which is represented by the wells Nos, 36, 38 and 48. This question unfortunately cannot be gone into for the present, not only because the boring registers of four wells Nos. 1, 2, 4,5 are missing, but what is more important, because nothing is known at present about the deeper structural features of the Twin- ` gon tract. To me the new feature seems sufficiently represented | by the petroliferous sand found at 230 feet above sea level in No. 6, 240 feet in No. A, and 250 feet in No. ro. On the other hand, it (, 152. ) found at the following levels :— YENANGYOUNG. 107 must be mentioned that the boring register of No, 46. which should fall into this region, exhibits nothing unusual, However, the question must remain open for the present until the deep wells drilled in the Twingon tract shall give further indications as to the way these indi- cations ought to be followed up. We must therefore content ourselves to assume that it has been unquestionably proved by two sections drawn at almost right angles across the northern end of the Kodoung oil tract, that the top of the 3rd oil-sand rises towards the centre, or, in other words, from the poor and indifferent wells to the rich well No. 47. In a third direc- tion this has been almost proved to a certainty. The result of the above argument is that the northern end of the Kodoung petrolifer- ous tract must form an irregularly shaped dome probably slightly elongated in north-east to south-west direction, the centre of which is occupied by a rich well and the outskirts by wells gradually decreasing in productiveness. So far the object of proving the series of intersecting folds has not been much advanced, but a section along the western side of the petroliferous tract ought to show whether there exist such undulations as supposed, and whether, this is the chief point, these undulations correspond to the ridges and bases of the intersecting folds. | The section connects wells Nos. 66, 19, 11, 18, 22, 12, 45, 58, 27 and 26 and in order to avoid unnecessary length of description it will be best to enter at once into the discussion of the upper level of the 3rd oil-sand, and to deal with the upper beds conjointly after- wards, Beginning at the northern end the ard oil-sand has been No. 66 ` қ 5 4 а 140 feet above sea level. No. 19 . ° . . 140 » » ” 3 No. II ° . . . 170 ,, وو‎ » » No. 18 « ° $ : 170 » » » э? No. 22 4 5 . 195 „э ” ” 38 No. 12 ° » А ° ° 160 , ” > 3 No. 43 - - š . ° 217 » son» No. 25 . ” š . 230 وو‎ » 99° p No. 58 ° ° ° . 187 ., , » 19 No. 27 . A ° ° 4 198 » » р р No. 26 ° ° . e . 210 5 » » ээ (0153 ) 108 NOETLING: PETROLEUM IN BURMA. The line rises therefore from the poor well No. 66, towards the indifferent well No. 11, remains steady up to the similar well No. 18, rises again to the rich well No, 22, falls quickly to the poor well No. 12, rises from these steeply to the rich well No. 43 (13 of course included) falls towards the indifferent well No, 58, here I may add that if the direction from 58 to the rich well No. 25 which runs at about a right angle to the direction of the main section is followed up it will be seen that there is also a considerable rise ;* from 58 the line rises again towards 27 and 26, beyond which this section can- not be continued, neither No. 55 or 48 bringing in any new feature, while No. 56 is most probably already on the eastern side of the belt. If we consult the section we notice that, excepting slight local differences in the thickness, the undulations of the 3rd oil-sand are followed by clay (e) but above the latter bed we notice some very curious differences which will presently be discussed. These facts I believe prove sufficiently that the top of the 3rd oil-sand describes a series of undulations along a line which is almost parallel to the present strike of the strata. I will now attempt to show the connection which may exist between this undulating line representing a vertical, and the zig-zag lines probably representing horizontal contour lines, The theory of the intersecting folds as applied to the Yenangyoung oil field requires the presence of a trough or basin on the western side of the tract between wells Nos. 47 and 22, Unfortunately a connecting link is missing here, that is to say, a well between Nos. 19 and 18, and it may be ques- tioned whether it is admissible to place well No. 17 in this place. However it is quite evident that a ridge does exist extending from No. 47 in south-westerly direction, which is crossed by a line which connects Nos, 66 and 19, indicated by a rise. The presence of the sag or trough between 18 and 19 is not quite proved, but it seems to be indicated by the rise from Nos. 19 and 18 towards No. 11 and. further on towards No. 47. 1 For obvious reasons well No. 25 has not been included in the diagrammatic section, | ( 154 ) Es I E 3 m^ . Ë B. I F “ YENANGYOUNG. 109 Further, the theory requires the existence of a ridge between Nos. 18 and 12, on the top of which the rich well No. 22 is situated. _ There could hardly be anything more conspicuously expressed than is the presence of this ridge by the run of the top of the 3rd oil-sand ; note the rise from 18 towards 22 and the quick drop from 22 towards 12. Passing along this subterraneous ridge in a westerly direction we come to well No. 16, where the top of the 3rd oil-sand has been found at 180 feet above the sea level, thus indicating a fall in the height of the ridge. Another ridge must be j between Nos, 12 and 58 ; nothing seems better demonstrated than this by. the section exposed by - drilling wells. Again we observe that the richest wells are situated on the highest point, following the direction of the ridge towards west, we observe that in well No. 14 the top of the 3rd oil-sand is only 150 feet above sea level. A sag is supposed to exist between Nos. 43 and 27 as shown by the rise which exists between wells Nos, 58 and 25. The ridge on which wells Nos. 27, 28, 26, 48 are situated is proved to a tolerable certainty, but not so the sag following imme- diately south of it. It exists most probably because from well No. 26, where the top of the oil-sand is met with at 210 feet above sea level, there is a. decided fall towards the indifferent well No. 31 where it was found at 2oo feet above sea level. Following up the direction of this ridge in a westerly direction towards wells Nos. 29 and 28, we may observe again the usual fall in the level of the top of the 3rd oil-sand. In No. 28 it was found at 170 feet above sea level, whilst at No. 29 it was only 155 feet, It appears, therefore, that the richest wells have been found to be situated at such places where the petroliferous sand rises highest to the surface, and the poorer wells are found in places towards which the 3rd oil-sand slopes from richer localities. | When examining the younger strata in the boring registers we ( 155 ) 110 NOETLING : PETROLEUM IN BURMA, may observe at once a very curious feature. Very thick argillaceous beds are found in all the wells which are situated inside the areas in- dicated as depressions. This thick argillaceous bed was first noticed in well No. 11, extending from there towards No. 47 where itisdivided by a sandy layer. From No. 11 the argillaceous bed passes between Nos. 10 and 18 and to the north of No. 17. Its horizontal extension must have been very limited in this region. ` From north of No. 17 it must sweep around but outside Nos. 16 and 15, and it is seen again in the. same thickness; its horizontal exten- sion must be still more limited in this part. From there it passes outside No. 14, reaches up as far as No. 58, although not in the same thickness as previously noticed, and must pass west of No. 62, but east of No. 64, and passing No. 67 which is probably close to its western limit. It appears in its former strength again in No. 30, and reached up in the depression as far as No, 48. Slight traces are only noticed at No. 55, not at Nos, 32 and 35, but in well No. 39 it again assumes the former ss oÍ over 2oo feet divided only by a thin layer of sand. Its further extension cannot be accurately defined; at No, 60 it appears as a continuous layer of 260 feet in thickness, extends to the south towards No. 63, where it reaches 295 feet in thickness, from thence it sweeps round the southern end of the oil tract, being found in No. V with 295 feet,in No. VI with 356 feet, and in No. VII with 290 feet ; near this point it is lost and it certainly does not appear on the eastern side, but it unquestionably extends as far down as No. I where it has been met with inconsiderable strength. This argillaceous bed is followed by a sandy stratum, which gener- ally increases in thickness when the argillaceous bed decreases, and vice versá. It deserves mention, that this second sand which begins north of the oil tract, describes a similar series of folds to the third sand, although it does not contain oil anywhere. ection X.—Before turning to the eastern side I wish to draw attention to section X as this traverses the central ridge. This sec- ( 156 ) VENANGYOUNG. ` III tion hardly requires any explanation. From No. 14, where the top of the No. 3 oil-sand has been found at 135 feet above sea level, it gradually rises towards No. 25 where it was found at 225 feet ; from there it falls slightly towards the inferior well No. 37, more so towards No. 42, where it reaches the level of 170 feet above sea, and now, as may be supposed according to the theory, it rises again towards the inferior well No. 5o, where its level is 185 feet above the sea, This section affords, therefore, a very good idea of the slope on either side of the central ridge on which the rich wells are situated. The eastern side of the petroliferous tract.—In the same way as the longitudinal sections were constructed on the western side of the tract, a similar one might be constructed on. the ` eastern side, but unfortunately the wells are not so numerous there ; and the few which do exist areseparated by such long intervals, that it is impossible to construct such a complete section on the western side, I may, however, be allowed to quote a few instances; the rise of the surface of the 4th oil-sand from the poor well No. 52 towards the inferior well No. бо has already been mentioned ; the same applies to the tract from well No. 49 towards No. 53, or No. 40 towards No, 38. It would be useless to go further into details; I think the above has conclusively proved that, independently of the general structural features expressed in the dome like shape of the Yenangyoung oil: field, there exists a series of folds, transverse to the direction of the axis of the anticline, which must have existed previous to the forma- tion of the latter. It remains, therefore, only to explain the origin ` of these folds. d.—The original sedimentation of the petroliferous beds. In the foregoing section 1 have shown that the Yenangyoung oil field exhibits a very complicated structure, due to two causes, 242.:-- | ^ I. À transverse action, resulting in the creation of the anticlinal and longitudinal arch. 2. A longitudinal action, resulting in the creation of the intersecting folds. ( "15g 7) 112 NOETLING: PETROLEUM IN BURMA, Š I have further shown that the intersecting folds must have existed before the anticlinal arch was raised. The question to be answered is, therefore, by what hypothesis can we explain the origin of the folds 2 I think the theory to be promulgated will explain all the curious fea= tures, but before giving it in detail, it will be necessary to recapi- tulate a few facts. We may take it as proven that the petroliferous beds of the Yenangyoung oil field at least, were deposited near - the mouths of a large river, or perhaps in a lagoon, communicating with such a river. The proofs for this view are:— (a) The fauna discovered is the petroliferous beds. ' (à) The bedding of the strata. With regard to the first point, a mixture of terrestrial animals, mostly in rolled fragments, and marine fossils has been found in the petroli- ferous beds.. A mixed fauna of this type cannot possibly have been deposited far from the coast, even if we admit that the floating carcases of terrestrial animals have been carried away by the tides, for some distance from the shore. With regard to the second point, I have demonstrated that the stratification of the petrolifer- ous beds exhibits such curious features, that we feel bound to suppose that they were deposited in a water subject to periodical and sudden rises like those of tropical streams of the present day. I have above pointed out that itis only the action of a quickly rising current by which we can explain the local erosion and the subsequent deposi- tion of beds, hereby creating local unconformities. | think the above two views do notrequire any further proofs and, if accepted, the ground is clear forthe theory of the origin of the folds. 3 Such a phenomenon is in fact represented to some degree by a mud stream running down the slopes of a mud volcano, and it was in fact this observation which first suggested the theory. When the liquid mud has reached the less inclined basis of the mud volcano its speed slackens, until its front has come to a standstill, while the upper masses are still in a downward move- ( 158 ) YENANGYOUNG, 113 ment. The result is that those parts of the stream which were first arrested bulge out and a series of wrinkles, running transversely to the direction of the mud stream, are formed on its surface, which sometimes join each other, or in other instances burst, while some liquid mud flows out and fills up the unevenness between the wrinkles. I have described this above (page 47), but it will be seen that we have only to assume that this same process has been taking place on a larger scale to find the explanation for the intersecting folds, Let us suppose that the ground on which the petroliferous beds were originally deposited formed a plane slightly inclined towards the open sea, an assumption which is quite compatible with the view of their deltaic origin, and let us further suppose that this plane eventually became horizontal, On this inclined plane athick stratum of sand was deposited, followed by an argillaceous bed, and on this another sandy layer until the weight of these masses which were permeated by water and in a state of unstable equilibrium set them in motion, The whole mass would then slide down on the inclined plane until it was arrested by the change of the gradient. What would be the result of such a process? Certainly some- thíng very similar to whatis exhibited by the mudstream. The strata would bulge out, they would form a series of folds, transverse in di- rection to that of the movement of the strata, and they would be intersected by numerous cracks and veins filled with mud, which would also spread on the surface, perhaps filling out the interstices between two folds. The single beds thus set in motion and arrest- ed again, would certainly exhibit a great inequality of thickness as well as their surface would be very uneven, unless they are filled out by * eruptive" mud. | Now let us analyse how this theory agrees with the observed facts. | І have above pointed out (page 124) that the strange arrangement of the drilled wells suggested a peculiar structure. I have proved to some extent at least, that this peculiar arrangement is unquestion- ably due to the presence of some transverse folds in the upper Prome ! | (РШ, ) 114 | NOETLING: PETROLEUM IN BURMA. stage, which apparently do not reach to the surface, but which must have been formed previous to the deposit of the Yenangyoung stage. These intersecting folds represent the wrinkles on the surface of the mud stream or the folds which must have been produced by the sliding of the masses according to the above theory. Could we ascertain that they were slightly curved, the proof would be conclusive, but the data available for the present are too scanty to prove this. As it is we must rest satisfied that there exist such folds as required by the theory, and we have now to investigate the question whether there is any other additional evidence which supports the theory. Now what stronger proof can there be than the presence of veins filled with eruptive mud and the beds of eruptive mud injected between the other strata as described on page 83. In fact the presence of the mud veins becomes only intelligible in view of the above theory, and their more frequent occurrence in the southern part of the field tends to indicate the region which was under the greatest pressure which therefore was nearest to the termination of the downward movement, It is further quite obvious that when a series of beds is simul- taneously moving, and eventually arrested, the single beds must become in some parts compressed and in others stretched or thinned. In other words an individual bed must exhibit a great variation of thickness within a limited horizontal extent. 1 think that the sections of the deep borings have given ample proof on this point. Although we might explain the reduction of thickness by local erosion, the increased thickness can only be explained by compression. We may now even go a step further and suppose that while the above mentioned process was going on, younger beds were deposited on the top of those in motion, a supposition which would result in the most complicated structure of the series, | It seems almost quite certain that the sliding process was ter- minated before the deposit of the lower beds of the Yenangyoung (> бө. 4 YENANGYOUNG. 115 ‘stage began, because there is no indication of the intersecting folds in these beds, although it seems certain that they were deposited on . very uneven ground. The theory may be accepted ог not, but I contend that it ex- plains a number of very peculiar stratigraphical features in an un- strained manner, for which it would be difficult to account in any other way. I wish however to say that I do not want to generalize ; the folds have hitherto been only observed within the limits of the Yenangyoung oilfield, but it is quite probable that they may also occur elsewhere. D.—General conclusions, and future prospects of the Yenang- young oilfield. Тһе numerous deep borings have shed so much light on the extension of the Yenangyoung oilfield, that we are now in a position to state with comparative accuracy that the Yenang- young oilfield is of very limited extension, hardly exceeding 350 acres in superficial area. With regard to the vertical extension we are in a less definite position ; we know that up toa depth of nearly a thousand feet a series of sandy beds occur which may be petroliferous or not, Whether the lower boundary of the oil bearing series has been reached or not is impossible to say at present. Only an actual test ‘will decide this question, but for the present it seems to be proved beyond doubt that it is the third oil sand, met with at _ depths averaging from 200 to 250 feet from the surface up to about 300 to 350 feet, which chiefly supplies the present yield. As already stated, it is impossible to say whether richer sands may exist at greater depths or not, and we have therefore only to deal with those parts of the oil bearing series of which we know some- thing definite. We know therefore as well as has been ascertained for the present, that up to a depth of about 9oo to 1,000 feet only One bed of sandstone has been found capable of producing oil in quantities, It is from this bed that the bulk of the pit wells and nearly al) the drilled wells draw their oil. It is safe to say that 12 | ( 161 ) I 116 NOETLING: PETROLEUM IN BURMA. about 75 per cent. of the total yield is derived from the third oil sand ` and if this bed shows signs of exhaustion, the end of the Yenangyoung oil production will not be far off. We will have therefore chiefly to investigate whether such signs are noticeable or not. For this purpose it will be convenient to divide the oilfield into two parts according to the method by which it is exploited, because, as we will ` presently see, other factors besides exhaustion tend to shorten the life of at least a certain portion of the oilfield. The two parts are the Twingon and Beme reserve forming the northerly and southerly part of the oilfield chiefly exploited by the natives, and Kodoung, the central part exploited by deep wells. | A.—The native reserves (Twingon and Beme tracts). With the exception of the drilled wells inside the lots, which are the pro- perty of the Government, these two tracts are at present exclusive- ly worked by pit wells. As stated in the economic section, the method of extracting oil by pit wells is restricted by the depth to which the labourer digging the well can safely go without resorting to artificial ventilation. ‘This limit can be fixed at 320 feet depth at most. When, therefore, all wells which can possibly be constructed within the boundaries of the native reserves have reached that depth the production must come to a standstill unless the method of drilling is resorted to. A decrease in the production of the pit wells need therefore, by no means, indicate the near exhaustion of the area exploited by these wells, it only proves that the beds capable of being reached by pit wells, that is to say, the first, second and part of the third oil sand are exhausted. The deeper part of the latter may still contain a considerable quantity of oil, inaccessible, however, by the native method of exploitation. i We will have therefore to answer the question, does the depth of the present productive wells in any way reach the above limit? As will be seen later on there are at present 519 productive wells; out of which there are about 107 which have been constructed since the close of 1893, and there remain therefore 412 wells, or ap- proximately 80 per cent, which were in existence previous to 1893; (30x 8 : ves 768 out of these 412 wells І selected 328 wells of which it could be proved that they had been permanently productive since the beginning of 1801 or during the last four years, all the others were disregarded. These 328 wells, representing 65 per cent. of the total number, supply 64 percent. of the total production and are therefore of the greatest importance in answering this inquiry. It is obvious that, if these wells begin to show signs of exhaustion, the production must naturally decline, unless other means are devised to keep it up. These 328 wells, all of which have been identified, had an aggre- gate depth of 67,340 feet in 1891,; that is to say, the average depth of each well amounted to 205 feet, In 1893 these same wells had an aggregate depth of 73,471 feet, or the average depth of each well had reached 224 feet from the surface. In 1895 the depth of these wells had increased to an agğregate of 74,952 feet or each well averaged 228 feet in depth. These figures will be more impressive if we express them in percentages of the possible depth, estimated at 320 feet; in this case - the average depth of each well amounted to— in 1891 . ° ° ° . 64 рег cent. of possible depth, » 1893 x A “ ë ° ° 79 эҙ 35 35 » 1 895 ° ° ° . . ° 7 1 ” 5 5 » The above figures unmistakably prove therefore that 65 per cent, of the productive pit wells have reached at the beginning of 1895 71 per cent. of their greatest possible depth. In other words, 65 per cent. of the existing productive wells, supplying 64 per cent. of the total yield of oil, have reached such a depth, that they approach very closely their maximum depth, which they would reach within the next seven years certainly, unless the difficulties in reaching that depth become so great that they had to be previously abandoned. From this point of view the outlook is a very serious one, and the more so because it is based on undeniable facts, ( x83 7) - 118 NOETLING : PETROLEUM IN BURMA. It may, however, be counteracted in two ways, one of which has: already been referred to: these are— (a) by increasing the number of productive wells, (ó) by adopting the system of deep borings. As regards the first remedy it has already been largely drawn . upon ; 107 new wells are oil producing, 151 wells under construction are expected to produce oil in a short time, and 281 places have been ` selected on which to construct new wells. Sofar so good, but the native reserves as well as the Yenangyoung oilfield cover only limited areas ; the native reserves have been demarcated in such a way as to allow room for a total of 2,250 pit wells (see page 233). Out of these 2,250 well sites, 1,190 are already occupied, and there remains therefore only space for 1,060 new wells, —theoretically at: least. Whether it will be possible to locate these 1,060 wells among the already crowded wells remains to be seen; itis my opinion that this is very doubtful, and that the nature of the land hardly allows for half this number. However that may be, itis certain that the decline of production caunot be counteracted by an unlimited increase of the productive wells. It may be that this remedy will answer, say, forthe next five years, but the day must surely come when it will fail, and when the wells will all have reached their greatest limit of depth, and that day will mean the end of the native oil industry, at least as regards the system of exploitation by pit wells. As far as my experience goes this day cannot be very far off, and if the facts are correct it ` will occur within the next ten years, perhaps even within a shorter | period. As already stated this by no means proves that the native reserves are entirely exhausted, it proves only that the upper parts, accessible to pit wells, are exhausted, and that in order to exploit the deeper parts, another system of exploitation will have to be adopted. That there is only one way, that of deep drilling, need hardly be explained, but it may be doubted whether the natives | are capable of availing themselves of this method. As far as my experience goes I seriously donbt it; none of the present well owners ( 164 ) YENANGYOUNG, 119 commands the capital necessary to cover the first outlay, nor is it probable that their suspicious character will allow them to combine . and raise the necessary capital among themselves. I believe that they will eventually sell the wells which are useless to them for a trifle to those who by their superior methods may give a new life to the oilfield, provided, of course, the strata have not been ex- hausted, a probability which we will have to examine now. In a previous paper! I wrote the following with regard to the pit wells: “As regards the average daily production per well we notice a considerable decrease in the total average since 1888 from 561 viss to 47:65 viss. Of the different classes the highest decline will be noticed in the IIIrd class, if we except the Vth class as containing too small a number of wells to give a reliable result. We there- fore see that in that class of wells, which contributes the largest share to the production, a very considerable decrease of the average production, amounting to 14'6 per cent. of the production in 1888 took place. In other words that bed of the oil bearing strata which hitherto supplied six-tenths of the total production shows unmistakable signs of exhaustion." I emphasized this view repeatedly in the paper above quoted, and I am now in the position to check it. I select again the 328 wells, which have been in continuous working order since the beginning of 1891, omitting all those which have been added in the meantime. The aggregate daily production of these wells amounted to— in 1891 Š А - - А ate Q ы 16,035 У155. » 1893 BE TU SR ЕТУ TARRO CERA s > 1895 ° . ° `. ° ° Ф ә 19,200 وذ‎ that is to say, the average daily production of a single well was— in 1891 . 4 а ^ ° А x к Е 51'6 viss, » 1893 % a ° 9 ° . ° E . 67°7 ” м 1995 , . ° 9 . . . . E 585 5 1 Report on the Petroleum Industry in Upper Burma, Rangoon, 1891, page 33. ( 165 ) 120 NOETLING: PETROLEUM IN BURMA. ^ I think these figures show sufficiently that the bed from which now 64 per cent. of the total production is drawn shows unquestionable signs of exhaustion; we notice therefore the same phenomenon as in 1891 when a decrease in the average yield was observed as against 1888. This decrease was at once counteracted by an energetic | deepening of the wells which was in fact carried out to such an extent that each well was increased 19 feet in depth on the average. The result of this operation proved a success and the average production per well rose to the extent of 16'I viss per day. Between 1893 and 1895 these same wells were again deepened to the extent of 4 feet on the average per well The operation did not, however, prove a success, because the production instead of rising declined to the extent of 9'2 viss per well per day. so that at the beginning of 1895 each of the 328 productive wells which represent 65 per cent. of the total number, and. supply 64 per cent. of the total production, produces only about 7 viss more than in 1891, although each well has been deepened to the average extent of 23 feet, since that year. Were therefore the production of the native wells not supported by 107 recently constructed wells, ех-: ploiting a part of the reserve hitherto not worked, instead of an increase, the production would show a distinct decrease as compared. with 1893. In fact we are in a position to estimate that decline with some precision. Under the above conditions the decline of the 328 wells, as compared with 1893, would amountto 90,528 viss per mensem. x This however does not represent the total amount of decrease, there are 84 more productive wells! which have not been included among the 328 wells because their history shows that they have not been productive for the whole time since the beginning of 1801: As it is safe to suppose that these wells have been influenced by the 1 Out of these 84 wells, 78 existed previously, while six were added during 1895, these being dug in the older part of the field have not been included among the other wells dug in the new parts, and it is supposed that their vom oma was equally affected | with the general exhaustion as the others, ` de СГ. 166: ) YENANGYOUNG. 121 decline noticed in the 328 wells, they would show a loss of 23,184 viss per mensem ; the total decrease of the production originating from the exhaustion of the petroliferous sand would therefore amount ` to 113,712 viss per mensem, or everything remaining the same the average monthly production in 1895 would have amounted to 629,446 viss, instead of 788,297 viss. | Instead of the production having fallen off, it has actually risen to the extent of 45,139 viss per mensem, as against the preceding year, while the productive wells have increased to the number of 107 as compared with 1893. The question may therefore be raised whether the production of these 107 new wells is sufficient to balance the es- timated loss in the production of the 406 older wells and to account for the increase ; in order to answer this satisfactorily I have made the most careful enquiries about the production of these 107 new ` wells which amounted to 6,423 viss per day or 192,690 viss per mensem, or 33,837 viss per mensem above the required amount, We see therefore that not only do the new wells fulfil the required conditions, but they actually supply somewhat more than required, from which we may naturally infer that the aggregate production of the 412 old wells is a little smaller than has been calculated. We may therefore consider it as proved that notwithstanding the increased depths of the wells, the production has declined, a phenomenon which may be considered as the surest indication of the exhaustion of the bed exploited by these wells. з I think that the above conclusion bears out my statements made in 1891, namely, that the bed of petroliferous sand which sup- plies six-tenths of the production begins to show signs of exhaustion. I purposely refrained from taking the state of wells in 1888 into consideration, because I am unable to identify the individual wells of that year with those considered above, but I firmly believe that they would prove the same condition. It is quite possible that when boring deeper fresh parts of the Өкі oil Беагіпр sand will be opened out, but as І have pointed out above, © 167 ) 122 NOETLING : PETROLEUM IN BURMA. the difficulties in getting beyond a certain depth prove unsurmount- able to the native well digger, and the only way to extract the petro- leum from the deeper strata would be the construction of drilled wells. It must, however, not be entirely forgotten that even those may prove futile, and that the third sand is already nearly exhausted within the boundaries of the reserves. This can however be only proved by an actual experiment. There are, I may state, some facts which in a measure tend to support such a view, but into which it is needless to enter here. To sum up shortly I believe the prospects of the native reserves are as follows :— r. It is very probable that within the next five years digging operations will be most energetically carried out, and the number of the productive wells will increase. 2. The production is likely to increase aliii more, although to no considerable extent, but in no distant future it will rapidly fall off, partly because the pit wells have reached their greatest depth, partly on account of exhaustion of the petroliferous sands. 3. The production of the Beme tract which has shown marked . signs of decline as late as 1891 continues to fall off. 4. The Twingon reserve has probably already passed the ridin of its existence, and its production will mp fall off within a few years, . 5. Although deep borings might delay the final end for some time, by exploiting deeper strata, it remains to be seen whether they will be successful or not, The chances are however more in favour of failure. I claim that my views regarding the prosperity of the oil bearing tract have been borne out by facts: In 1888 I wrote д “The Twingoung oil field is at present at the zenith of its produc- tion, but still a small increase may be expected for the next few | 1 Report on the Oil fields of Twingoung and Beme, Rangoon, 1889, and Records | . of the Geological Survey ot India, 1889, vol, XXII, | ( 168 ) * b D \ YENANGYOUNG. 125 years. The Beme wells have nearly extracted the oil existing in the oil bearing sandstone and a decrease of production is to be . expected." B. The area exploited by the drilled wells (Kodoung). No such difficulties as regards limited depth obstruct the drilled wells. If it were known certainly that an exceedingly rich oil sand were to be found at 2,000 feet, every well would at once be brought down to that depth. The future of this area is therefore simply dependent upon the quantity of oil stored in the different sands and the annual off take. Although the latter is well known it would be exceedingly rash to form an opinion about the former. We know that the Kodoung wells draw their supply chiefly from the third oil sand, but how long this will last is difficult, if not impossible, to say. The question will be the more difficult to answer if we assume a general flow of oil towards the wells; in this case the production will of course last longer than if only dependent on the oil within the boundaries of Kodoung, because the oil is attracted from the more distant places towards the deep wells. However there will probably come a day when the third oil sand will be entirely dry; in this case the wells will have to exploit the deeper sands. Whether those are capable of supporting the present large production is impossible to say, so far as can be judged from the few observations the chances are not favourable, however I do not wish, considering the inconstancy of the strata, to attach too much weight to those few instances in which we have become ac- quainted with the sequence of the beds below the third oil sand. Taken as a whole the Yenangyoung oilfield has by no means answered the expectations which were entertained about it. It is limited in area, and we may almost certainly assume that its pro- duction will always be a modest one. It is almost certain that its production will rise somewhat during the next few years, but it is most probable that then a decline will set in. My opinion is that ( 169 ) 124 NOETLING: PETROLEUM IN BURMA, this decline will take place within a limit of ten years or even earlier. | In conclusion I may point out that the views which I expressed in 1888 have been borne out by the facts. In my first paper I wrote as follows: “On the whole there is every reason to believe that the oil industry will develop in the future and will rank amongst the import- ant mineral industries of Burma. Wild ideas about beating or com- peting with American or Russian oil cannot be too strongly deprecat- ed as being only too likely to prove utterly illusory." In confirmation of the above I simply refer the reader to the chapter on production. CHAPTER V.—THE OCCURRENCE OF PETROLEUM NEAR YENANGYAT. SECTION 1.—GEOGRAPHICAL POSITION; AREA OCCUPIED BY THE OIL FIELDS; PHYSICAL GEOGRAPHY. The small village of Yenangyat, or Yenanchit as it is sometimes spelt, is situated in Lat. 21? 6' and Long. 94? 51' E., on the right bank of the Irawadi, nearly opposite the ruins of old Pagan. It is for this reason that this occurrence has sometimes been called the Pagan oil field, or even the name of Paganyat has been substituted. It seems that the occurrence of oil at this locality has been known for a long time, because Crawford! mentions that oil oozes out from the rock at this locality. 'The members of the mission to Ava 2 apparently visited Yenangyat, and Dr. Oldham was then of opinion that the exploitation of this place might perhaps be projected. It - seems that the natives started the construction of pit wells а few years later, but so far the production has been very small. Wells are dug in three narrow ravines, running, roughly speak- ing, parallel to each other, north of the village of Хепи The names ol these ravines from south to north аге— 1. Yenaung-chaung. 2, Ok-Khyaung-chaung. 3. Ywaya-chaung. 1 Crawford, mission to Ava, Vol. II, page 18. 2 Yule, mission to Ava, Appendix A, page 320. ( 170 ) b С YENANGYAT. 128 The productive wells are all situated in the Yenaung-chaung ravine, but quite recently some successful wells have been construct- . ed in the Ok-Khyaung-chaung ravine. The area occupied by these wells is very limited, and in no case exceeds a few acres; this, however, by no means indicates the real extension of the petroliferous sands, because the natives have been prohibited by physical difficulties from extending the area ex- ploited by pit wells. The country around Yenangyat is of the most rugged nature; a hill range, beginning near opposite Singu and gradually rising to 1,184 feet above sea level in the Seikaywa pagoda, runs for about 25 miles _ from its commencement quite close to the right bank of the lrawadi. In fact its eastern slope forms the bank of the river itself. The eastern slope is steep, very rugged, and is composed of a mass of low hills, possessing a more or less inclined eastern and a steep western slope, and forming a tract of about half to a quarter of a mile in breadth along the river bank, No sooner 15 this tract crossed than the slope rises quickly and uninterruptedly, frequently forming steep pre- cipices to the crest of the range. The western sides slope more gently, but here we notice also numerous more or less isolated hills, which present a steep eastern and a more ог less inclined western face. We will presently see that these features are solely due to stratigraphical conditions. ` Itis owing to the nearness of the crest of the range to the river bank that the ravines which drain the eastern side are very short, generally very steep at their head, but slightly inclined towards their mouth, and as the magnetic bearing of the range is almost due north and south, all the ravines on the eastern side run due east, affording thus generally very good cross sections. The slopes of the ravines are always very steep, the ravines accordingly narrow, and much twisted about. No more difficult land could be imagined for any industrial undertaking, even small plots of level ground being very rare. ( 171 ) 126 NOETLING: PETROLEUM IN BURMA. _ SECTION 2.—GEOLOGICAL FEATURES. A. The pliocene or Irawadi sertes. The lithological characters of the lrawadi series differ in no way from those mentioned in previous chapters. We notice soft whitish or yellowish sandstones, sometimes with strings of hard concretions and ferruginous conglomerates. I have not found any fossil remains on the eastern side of the Tangyi-range, but ас- cording to. Dr. Oldham's statements, vertebrate fossils are not uncom- mon on its western side in the valley of the Yaw river. Within the area of the Yenangyat oil field I have not attempted to subdivide the Irawadi series, but I think it is quite possible that a subdivision similar to that of Yenangyoung will be feasible when fossils have been systematically collected in the Yaw valley. B. The Miocene. (a) The upper miocene or Yenangyoung stage. Lithological characters.—Although in general the same, the Yenangyoung stage as developed near Yenangyat differs in the pre- ponderance of argillaceous beds, while the more sandy beds are sub- ordinate. . | The clay is generally of olive green colour, but bluish beds are not unfrequent, and in fact the bed which closes the series has a dark bluish colour. The usual hard concretions in strings or uninterrupt- ed layers are found throughout the series. They form sometimes the top of a hill, the overlaying elay being denuded away. The sandstones are yellowish or olive coloured, finely grained, generally soft, but sometimes they form hard layers. Gypsum is very common in all the argillaceous beds. Paleontological characters.—There was apparently an inver- tebrate fauna living during the deposit of the above beds, as indi- cated by numerous fragments of shells. 1 have, however, never succeeded in finding complete specimens, but some of the fragments apparently belonged to the genus Cardium, while others probably represent the genus Cyrena. | A q К y ] y YENANGYAT. 127 Subdivision.—Although in the absence of any well defined palzontological features a subdivision based on this evidence is . impossible for the present, a certain sequence of strata has been noticed, which seems to continue for a considerable distance in a horizontal direction. In descending over the beds distinguished are— a. Blue clay, a very conspicuous bed particularly marked by the contrast which its bluish colour forms to the overlying whitish yellow of the Irawadi series, In thickness it is between 40 and 50 feet, and as far as observed it seems to form a very constant horizon within the tract of the Tangyi range. à. Yellow sandstone; below the above МЫ pi clay follows a dark yellowish, rather soft sandstone of about 2o to 25 feet in thickness. €. Olive coloured clay bed of soft, thickly bedded clay of olive colour, containing large quantities of gypsum of about 60 feet thickness, The hard argillaceous concretions of this bed contain occasionally fragments of fossils. d. Signal hill sandstone ; a bed of sandstone of the same charac- ter as No. 2, so called because it forms the top of a hill where there is one of the main signals of the Yenangyat oil field survey, thickness about 20 to 25 feet, e. Olive coloured clay ; full of gypsum, the same as No. 3. Thick- ness about 60 feet. | f. Pagoda sandstone ; the same as Nos. 2 and 4; forms the sur- face of the hill on which the Sehwemyindin Pagoda has been built, it is apparently a little harder than the other beds ; its thickness being about 20 to 25 feet. g. Olive coloured clay, as before ; thickness about 40 to 50 feet. h. Sandstone, as before; thickness about 15 feet. z. Olive coloured, somewhat more bluish clay, forming a bed of approximately 190 feet in thickness. Strings of hard concretions are very common, covering the slopes in large heaps where the bed crops out. Forming an opinion from the above section, the total thickness of (^13 ) 128 NOETLING: PETROLEUM IN BURMA. the Yenangyoung stage cannot be less than 500 feet, and the chief subdivisions seem to form fairly constant horizons as may be seen along the eastern slope of the range (see Pl. XVID. (2) The lower Miocene beds or Prome stage. Lithological characters —They are the same as already described greyish glauconitic sands alternate with bluish, rather tenacious clays, Paleontological characters.—The uppermost bed of the Prome stage, a very glauconitic sand, which therefore appears dark green, has yielded a very interesting fauna, which I described in part I of this volume of the memoirs. It is unnecessary to repeat here the list of fossils. It is sufficient to say that they furnish evidence of an unmistakably miocene age of the beds in which they are contain- ed and that their character is purely marine. Local subdiviston—-The boundary between the Prome and the Yenangyoung stages is less well defined at Yenangyat than at Yenangyoung. In fact it may be questioned whether the sub- division of the miocene beds answers the natural conditions best. I have laid the boundary between the Prome and Yenangyoung stages above the first oil sand, but below the thick bed of olive coloured clay No. o, thus separating the beds characterised by abundance of gypsum in the argillaceous beds from those without gypsum, the arenaceous beds of which generally contain petroleum. As already stated, this subdivision may perhaps be an artificial one, and it would perhaps be better to consider the whole sequence of beds below the Irawadi series as belonging to one and the same series, but it must be borne in mind that the term “Yenangyoung stage” represents only the upper mio- cene beds which, owing to some characters, chiefly the colour of their sandy beds differ from the lower strata. The Prome stage, as defined, is almost solely known from the deep borings, the insignificant outcrop of the topmost oil sand being too badly exposed to be of any value. | | So far it seems that апу general subdivision is impossible. wells have revealed a sequence of arenaceous and argillaceous beds alternating and succeeding each other, but whether these can be con- ОИ АИ) Тһе ж oo. a 3 " YENANG1 AT. 129 sidered as constant horizons remains more than doubtful. All we may say is, that the upper Prome stage represents a very thick layer of clay which is subdivided by numerous sandy beds in layers of. varying thickness. 1 The upper beds of the Prome stage have been ascertained for a depth of about 1,100 feet from the surface, which after deducting those beds considered as belonging to the Yenangyoung stage allows about 8oo feet thickness for the upper Prome stage. It must, however, be at once added that this by no means represents the total thickness of the stage, which is probably much greater. In fact, it is almost quite certain that the drill is still far away from the base of the Prome stage. | The occurrence of petroleum.—As in the Yenangyoung oil field the petroleum is restricted to arenaceous beds, enclosed between layers of impermeable clay. These sands may: contain oil and water together, but the oil has always been found above the water. . As may be seen from the boring registers the petroliferous sands ~ vary much in thickness, the thickest bed of sand being recorded in well No. 66, with a thickness of 133 feet, but the quantity of oil it. contained was apparently only very small. So far not less than ten distinct petroliferous sands, following each: other in vertical direction, have been recognised, but it seems almost certain that this number by no means represents the total num- `. ber of petroliferous sands contained in the Pegu series. All the pro- — babilities tend to prove that further petroliferous sands will be found in greater depths, but it is quite impossible to. say whether they will be richer or not than those already found. Were it permissible to. draw any inference from the strata already known, the conclusion would be, that the lower oil sands are also very poor, but such a Statement would be premature as only the drill will give the much desired information, The six oil sands hitherto found in the wells are the following :— 1st oil sand.—This is represented by the same bed which crops Out in the Yenangyoung-choung, and from which oil was noticed K ( 175 ) 130 NOETLING: PETROLEUM IN BURMA. oozing out by previous visitors. It is from this bed that the pit wells | chiefly draw their oil. In well No. 3 this bed was found to have been 70 feet in thickness, in well No. r, 45 feet; while its thickness is re- duced to 18 feet in No. 2, 15 feet in No. 5, and it most probably does not contain any oil in No. 6. The sand was throughout of poor quality. 2nd oil sand.—A layer of sand containing oil, varying from 5 feet in thickness in No. 1, to 20 feet in No, 5; the intermediate strata between the rst and 2nd oil sand have an average thickness of 160 feet. It must be mentioned that the oil contained in this sand was under such a pressure that it freely flowed to the surface although in small quantities only. 3rd oil sand.—This petroliferous sand exhibits some peculiar- ities with regard to its thickness, it seems that at well No. 6 this sand attained a thickness of 88 feet containing, however, only gas; to the east, it split up into three different layers, separated by clay partings ; the upper one containing water, the middle one gas, апа the lower one was apparently dry ; in No, 3 it represented a bed of only 5 feet in thickness, separated by a thin argillaceous bed from a dry layer of dark sand of 23 feet in thickness, while at No. 2 the separating layer has disappeared and about 30 feet of dark sand containing a little gas and oil have been observed. It must remain doubtful whether the thin layer of grey sand found in No. t, above the 3rd oil sand should be considered as a part of it or an independent layer. | i It is thus seen that the thickness of these separating clay beds between the 2nd and 3rd oil sand varies, but it may be observed that the ard oil sand is found between 50 and 60 feet below the 2nd oil sand. 4th oil sand.—Like the former this bed seems to be very inconstant with regard to its thickness and its petroliferous qualities. In No. 5, where it has a thickness of 25 feet, it has yielded a small quantity of oil, but in the neighbouring well No. 4, where it is divided by an argillaceous bed, it contained no oil; in No. 2 it swells out to 62 feet,consisting of several well-defined beds containing oil at the top and ( 390.1) hi Rum. ae YENANGYAT. 131 ` water below ; the oil from the lower layer was slightly under pressure which brought the oil to 175 feet from the surface after being found at 509 feet. In No. 5, where it had a thickness of ro feet, it yielded no petroleum. In No. 6 two arenaceous beds of 27 and 45 feet respece tively are separated by a clay parting of 37 feet thickness ; the lower part of which has been stated to form two distinct beds; the upper containing a small quantity of oil, the lower gas and water only. It is most probable that the lower bed represents the 4th oil sand, because it corresponds in level to the 4th oil sand which should be found about 100 feet below the 3rd oil sand. 5th oil sand.—This layer is remarkable for the constancy of its thickness ; hardly exceeding ro feet, it contains oil only in Nos. 3 and 5, While it is dry in No. 1, and contains water in No. 6. Itisremark- ble that the oil occurring in this sand in No. 3 was under heavy pressure, as it flowed over the top of the well although met with at 513 feet depth from the surface. This bed is about 50 feet below the 4th oil sand. 6th oil sand.—This bed reaches a thickness of about 60 feet in No. 6, where it contains a small quantity of water, in No. 5 its thick- ness is 45, while it is reduced to 10 feet in No. 3, and from there it seems again to have increased in thickness towards Nos. 1 and 2. 7th ой sand.—A thin bed of not more than 9 feet in thickness. | hitherto only found in No. 6 well, and probably two thin beds contain- ing gas may represent it in No. 2. Sth oil sand.—This bed has apparently been found in all the wells, it being about 25 to 30 feet. It seems that the thickness of the separating clay bed varies very much, and with it therefore the depth at which it is found below the 7th oil sand. It is smallest in No. 5, but increases quickly towards Nos. 1 and 6. 9th oil sand.—A thin layer of 7 feet found only at Nos. 6, 1 and 2; as it is separated from the following by a very thin clay parting it remains doubtful whether it should not be considered as the top portion of it. 10th oil sand.—A very thick bed, which in No. 6 has a thickness K2 был уг 132 NOETLING: PETROLEUM IN BURMA, of 133 feet, without its lower limit being touched. It has most probably been identified in Nos. 1 and 2, but here the drill did not go so deep as in No. 6; it seems that it contained only a very small quantity of oil. | The occurrence of oil calls for no further remarks, as it has been already mentioned that it seems subject to periodical fluctuations like that of Yenangyoung. The only remarkable feature is the com- paratively high pressure prevailing in some of the oil sands, which in one instance at least has forced up the petroleum from over 500 feet. SECTION 3.—STRATIGRAPHICAL FEATURES. . A.—T he superficial sections. As already stated the ravines, which cut through the hill range at almost right angles, generally afford very good cross sections, but at the present only those in the Yanaung-choung ravine have been examined in detail. From the sections on Pl, XVI, it will be seen that next to the river, the beds of the Irawadi series are exposed along a zone, whose breadth varies very much; it is about 500 to 600 feet in this section. The strata closest to the river bank stand nearly perpendicular, but a little further away, the dip is eastern, but still very high and not below 7o° within the boundaries of the lrawadi series. The dip slowly decreases down to about 40? to 45? at a distance of about 1,200 feet from the river, when rather suddenly it changes to about 7? west. The strata form therefore an unsymmetrical anticlinal fold the eastern side of which is marked by high angles of dip, which however rapidly change from about 90° to 45° towards the apex of the anticlinal, while the western side is characterised by a low and very constant angle of dip. The remarkable topographical features of the Tangyi range are therefore easily explained by its geological structure. The eastern side where we see a mass of rugged low hills with steep eastern slopes, is represented by the steeper side of the fold. On the western side, where the angle of dip is lower, the natural slope is more gentle, and the nature of the ground therefore not so rugged. Б. YENANGYAT, 133 The strike of the strata is nearly due north and south, but it seems ` almost certain, that it changes along the axis of the anticlinal which, instead of running straight, apparently presents an undulating line. Unfortunately I had no time to study this subject in greater detail. It seems to me that the dip of the strata also varies, a matter which might be expected, and it further seems that this results in the forma- _ tion of a dome like structure as at Yenangyoung, but time did not allow following up this matter. It is to be hoped that the deep borings which are soon to be carried out north of the Yanaung- choung ravine will shed light on this question. B.—The sections of the drilled wells. "The number of drilled wells in the Yenangyat oilfield, is very small; when I left the locality at the beginning of 1895 there were only six, while a seventh was just going to be constructed, Out of these six, one, No. 4, did not afford any information on the stratigra- phical features of the Yenangyat oilfield, because it was drilled on the eastern side of the anticline at a place where the western dip was almost go°; the result might have been anticipated. Except a thin bed of clay, the drill recorded nothing but sandstone, most probably the same bed which it never left for the whole depth of the well. It is remarkable that the water found in this well was under high pressure, indicating therefore a head of water, which must be found at a considerable distance towards east, as the low and narrow Taungsin ridge, can hardly be supposed to yield the quantity. ` The five other wells were drilled in an almost straight line run- ning east and west, that is to say, they were placed on a line which would afford a very good cross section through the deeper strata, and from this point of view the records of these few wells are exceedingly valuable, From the records it seems that the series affords the same mono- . tonous sequence as recorded from the Yenangyoung oilfield. The correlation of the strata was however much easier, because, to judge from the great regularity of the superficially exposed strata, a similar constancy might be expected in greater depth. (7479 ) 134 NOETLING: PETROLEUM IN BURMA. In going through the records the first feature noted is the | predominance of argillaceous beds; in fact if we look at the sections on pl. XVII it seems that the sequence consists of an enormous argil- laceous series, here and there parted by thin beds of sandstone. The predominance of the argillaceous beds in greater depth is therefore quite in accordance with the character observed in the series super- ficially exposed. It will be seen further, that the thickness of the various beds is somewhat inconstant, a fact which has been mentioned already (pp. 79 ff.). Although there seems to be a greater regularity in the horizontal extension of the strata than may be observed at Yenan- gyoung, it is certain, that a bed may locally attain a great thickness whilst rapidly thinning out in other directions. On the other hand, we may safely assume that certain beds observed in the bores, are of very limited extent. | The first oil sand affords the best instance of the first case ; it rapidly increases in thickness from well No. 5, towards No. 3, while it ` equally rapidly decreases from No. 1, towards No. 2. | As an instance of the second supposition, the two sandy МЕС! | found іп wells Nos. r, 2, and з between ће first and second oil sands may bequoted. Itis absolutely certain that these two beds have not been found in No. 5, where an uninterrupted bed of clay separates the first and second oil sand. We are therefore bound to suppose that they thin towards west. These instances could be easily increased in number ; it seems for instance quite certain, that the two thick beds of clay, which apparently divide the third oil sand in No. 5, nip out to the west and are replaced by sandy beds, thus forming a thick arenaceous layer which represents the third oil sand in well No. 6. | - „It is a plausible supposition, that when such changes take place in a transverse direction, they would equally probably be met with in a longitudinal direction. The chief beds of the Yenangyoung stage, as superficially exposed, seem to be opposed to such a view, as they are apparently very constant, but it does not necessarily follow that the same applies to the petroliferous beds. However this question ( 180.4) YENANGYAT. 135 must be left undecided for the moment, but to me it seems highly pro- bable, that the petroliferous beds are subject to irregular changes in every direction. For the above mentioned reasons the identification and correlation of each single bed has been a little difficult, although much less so than at Yenangyoung. It will be seen from the sections that the various levels in which one and the same bed was found in the different wells are due to the dip of the strata. The lesson taught by the deep wells might have been a priori deducted from the structural features at the surface: any well situated east of the crest of the anticlinal is sure to be a failure from a commercial point of view, as, even if not too far off, the high dip will cause the petroliferous beds to be found at such a depth that they are practically inaccessible, Boring operations will therefore have to be more or less to the western side of the anticline, but in this case we see that there are almost insurmountable natural difficul- ties in the way of reaching a given petroliferous bed, say the first oil sand, at a given distance west of the crest of the anticlinal. As already stated the ravines on the eastern side of the Tangyi range are very short, the crest of the range being close to the river. A well. ‘sunk at a spot too far west from the crest of the anticline would therefore have to pass through a large thickness of younger strata before reaching a given bed; the length of the ravines being very short, and the eastern slope of the main ridge being very steep; suitable sites for wells would be very difficult to find. The range . would probably have to be crossed and the well drilled on the western Side. Ineither case, a large series of younger strata would have to be - drilled through before the petroliferous sands were reached. Further | test wells should therefore be sunk where streams have eroded longer ravines on the eastern slope than at Yenangyat in order to avoid the unnecessary drilling through the unpetroliferous younger beds. The possibility that wells sunk in more westerly localities will prove unprofitable must, however, not be quite disregarded. lt is quite possi- ble that the petroleum rises towards the highest parts of the anticline at = Yenangyat and that the lower parts of the petroliferous sands contain ( 181 ) 136 NOETLING: PETROLEUM IN BURMA, no oil, but at the same time it must be mentioned that as proved by the deep wells the petroliferous zone has a breadth of not less than 2,200 feet, chiefly on the western side of the anticlinal, and that so far по" thing has shown that its western limit has been touched by well No. 6. SECTION 4.— FUTURE PROSPECTS OF THE YENANGYAT OILFIELD. Unfortunately we are not in so good a position for defining the boundaries of this oilfield, as we were in the Yenangyoung area, but still certain conclusions may be drawn, partly based on actual observations and partly on inference from other localities. For the present it is impossible to define the horizontal extent of this field, because the number of deep borings is small, and those which exist are situated along an almost straight line, running east to west in the Yanaung-ravine. These borings have proved, as might have been anticipated from the structure of the beds, that the eastern boundary of the oilfield coincides with the central axis of the anticlinal ; from this point the petroliferous sand extends for at least half a mile, and probably more, in westerly direction. Much less certain are we with regard to the extent of the oil field in a north and south direction, but, if I am right in my conclusions, the field is very limited along this line. It seems that no oil has been found immediately south of the place where the productive wells are situated, and it is almost certain that the wells dug by the natives in the Yawa and Ok-Khyoung ravine hardly produced any oil at all; of course the experience gained by these shallow wells does not prove much, but as we know that the Yenangyoung oilfield is very limited in either direction it is only just to infer that the same holds good for the Yenangyat oilfield. In this case the area of the Yenangyat oilfield would hardly exceed one mile in length, and if we were to ` suppose that well No. 6 has almost reached the western boundary, the total area-of the Yenangyat oilfield would barely exceed half a square mile. ^ As regards the vertical extent of the oilfield we are even less able to say anything certain about it; but we may assert with safety that fno richer sands are found in greater depth the prospects of the ( 182 ) YENANGYAT, 137 Yenangyat oilfield are very poor ones. The first oil sand has run almost dry, and those tapped by the deep borings have for the present yielded only a small quantity of oil, although this has been produced by flowing wells. The existence of these flowing wells is the only bright and encouraging feature in the otherwise dark prospect of the Yenangyat oilfield, but as a whole they do not prove much about the future prospects. All that the flowing wells show is that in the sand ' from which the oil has been drawn a pressure exists which is suffi- cient to bring the oil in a small stream to the surface. So far as our present experience goes, nothing indicates the existence of a large quantity of oil, certainly not within the sequence of strata, from the surface to 1,100 feet in depth. As it may be doubted whether the small quantity of oil produced by the drilled wells is sufficient to pay the expenses of drilling, it may be safely stated that, unless the next test wells prove the existence of a rich oil sand, the Yenangyat oilfield will have to be abandoned as unpro- fitable within a short time. CHAPTER VI.—THE OCCURRENCE OF PETROLEUM АТ | OTHER LOCALITIES IN UPPER BURMA. À monograph dealing with the occurrence of petroleum in Upper Burma would be incomplete without at least a mention of the other localities in Burma where it is known to occur, although these localities may not have been examined in detail. I do not pretend to say that the following list is exhaustive, in fact I am rather inclin- ed to think that petroleum will eventually be discovered at other localities too, when a thorough exploration of the country has been made. For the present I am able to add the following :— т. Bondoung.—Its geographical position may roughly be defined as about Lat. 22° 30’ Long. 94° 45'. The place where the petroleum oozes out is surrounded by almost impenetrable jungle, which covers the valley of the Patalon-choung, a small feeder of the Chindwin river, . about five marches south of the village of Mingin in the Lower Chind- win district. As far as I have been able to ascertain the petroleum (. 183) 138 NOETLING: PETROLEUM IN BURMA. oozes out from a fissure in the rocks, filling a small tank; the strata apparently form an anticline, and most probably belong to the Prome stage. No use has ever been made of the petroleum of this place, a fact which is easily explained by its isolated occurrence. 2. Yebyu.—Lat. 21? 35' Long. 94? 10. Yebyu is situated in the Pakkoku district, about 20 miles north west The small village of of the village of Pouk. The oil oozes out of several places quite : close to the village on the slope of a hill range, which is apparently formed by an anticlinal arch of strata belonging to the Prome stage. The country is densely covered with jungle and therefore very ill- adapted for geological researches, The villagers have extracted the oil in a few shallow pits, but the production seems always to have been very small. 3. Indin.—Lat. 23? o” Long. 94? то. The village of Indin is situated in the Upper Chindwin district, on the eastern bank of the Myittha stream, a feeder of the Chindwin river. Petroleum is said to have been found east of the village. I have not visited the place myself, and am therefore not in a position to verify this statement which is based on information received in 1889 from the subdivisional officer. | | 4. Yenan village.—The small, in 1889 deserted, village of Yenan, is situated at about Lat. 24? Long. 94? 30' in the Upper Chindwin district, on the right bank of the Yu river, a feeder of the Chindwin. The strata belong to the Prome series or form at this village an anticline, which is cut through by the Yu river. On the top of the anticlinal arch rises a gas well right in the middle of the river while some more wells which’ bring petroleum to the surface are in ` the village itself. The indications are, however, very small and the petroleum has apparently never been gathered by the natives. CHAPTER VIL—RELATION BETWEEN THE OCCURRENCE OF PETROLEUM AND THE MAIN STRUCTURAL LINES OF UPPER BURMA, - It will be seen from the foregoing chapters, that the localities where petroleum is known to occur in Upper Burma spread over a e asd) EAS „ы ҚАРА i DISTRIBUTION. 139 considerable area. The southernmost point is a little south of 19° N. Lat, while the northernmost point is about N. Lat. 24. Within . this area, stretching over five degrees of .latitude, petroleum has been found at about 14 different localities. But it is remarkable to note that excepting the most southern localities opposite Prome and west of Thayetmyo, all the others are west of the 95? of longitude and east of the Arrakan Yoma. If we further keep in mind that these localities are not very far east of the 95th meridian it seems almost certain that the occurrence of petroleum in Upper Burma is restricted to a well defined zone of about 40 miles in breadth, and striking along the eastern side of the Arrakan Yoma for a distance | of not less than 300 miles. I do not wish to insist that petroleum might not be found outside this zone, but there is a greater probability of finding new localities within this zone than outside of it, It remains now to be seen how the petroleum occurs within this well defined area, and whether we are able to discover some sort of a rule which might serve as a guide when further researches are made. It has been shown in preceding chapters, that everywhere in Upper Burma petroleum occurs associated with a certain structural feature of the strata, namely, within anticlinal arches. All the petro- leum localities are situated on the top of anticlinal arches. Further ` researches will therefore have to be made in this direction, that is to say, the chief attention will have to be paid to such parts of the petroliferous zone where the strata form anticlinals, If we enter the occurrences of petroleum on a map of Upper Burma we see at once that they form two well defined lines or belts . which perfectly coincide in their strike with the magnetic bearing of the Arrakan Yoma. The eastern oilline or belt we may call the Yenangyoung anticline, the western one the Minbu anticline. The Yenangyoung anticline.—The Yenangyoung oil belt includes the following localities, beginning south :— 1. Yenangyoung. 2. Singu. ` 3. Yenangyat. 4. Bondoung. ( 185 ) 140 NOETLING: PETROLEUM ІМ BURMA, It begins about 10 miles south of Minlin-doung and runs in a north-westerly direction for about 30 miles towards the village of Kyoukye : from here the anticline turns somewhat towards east and runs in а north-north-westerly direction vz Singu, Yenangyat, Pinchoung, Bondoung to the Chindwin river which it crosses east of the mouth of the Patolon-choung; its further continuation is unknown to me, The total length for which the Yenangyoung anticline has thus been traced amounts to about 180 miles, but it must at once be stated that along this distance hitherto only three localities, 2%2.:-- | | 1. Yenangyoung, 2. Yenangyat, . 3. Bondoung, have been found which yielded petroleum, Whether petroleum will be found at intermediate places remains to be seen, but there are certain indications of the presence of oil which serve as a guide for further research. The Yenangyoung anticlinal begins as a very flat arch south of Minlin-doung, but the dip increases and soon the arch becomes more and more pointed till it has reached its highest develop- ment within the limits of the Yenangyoung oilfield. Further toward north it flattens out up to a few miles north of Kyoukye : from there the arch of the anticline gradually rises, and becomes more pointed till its maximum near Yenangyat has been reached. It again flattens out, till it is scarcely perceptible near the village of Pinchoung, but it is beyond doubt that it rises again towards Bondoung. 1 have not fol- lowed up the Yenangyoung anticline further north than the Pinchoung, -:but even from the little we know, some valuable inferences may be drawn. I have pointed out that there exists a successive change of the angle of the arch of the anticline, which from being very obtuse gradually becomes acute and then again widens out. The result of this change will be that the top of a given bed gradually rises above a fixed level, and equally sinks back to its former level when the anticlinal arch again widens out. The natural result of this is the formation of a series of turtle back sbaped or dome like elevations ( 1567, et Рр МАРГ t DISTRIBUTION. 141 along the axis of the anticline. It is obvious that the presence of such a structure is revealed by the gradual rise and fall of older strata to- wards the surface along the axis of the anticline. The Yenangyoung oilfield affords one ofthe best instances of this kind of structure. So far as it is known at present the petroleum occurs in Burma below these dome like structures. It follows therefore that at such places where along the axis of the anticline only strata of the Irawadi series occur, it would not be advisable to search for petroleum, this substance existing at too great depths for practical exploitation, but that on the other hand, when the older beds as for instance those of the Yenangyoung or Prome stages are found, the probabilities of a successful petroleum find are very great. Within the area of the Yenangyoung anticline such places as Kyoukye or Pinchoung promise very little success, while at others, as Singu or Yenangyat, the geological conditions are more favourable. The Minbu anticline.— Unfortunately I have not been able to study the Minbu anticline sufficiently, to pronounce a definite opinion, and the following remarks must therefore be considered to be more or less speculative. It is very probable that. the Minbu anticline begins near Thayetmyo, where the occurrences of petro- leum at Padouk-bin and Banbyin, may probably belong to the Minbu oil line; it is also quite possible that those opposite Prome belong to the same oil line, but at present there is no proof of it. From Thayetmyo the anticline runs in a north westerly direction towards Minbu, but north of this place its continuity is interrupted on account of the alluvial plain of the Son river intervening. It is very probable that the petroleum springs of Yebyu are situated on the continuation of the Minbu anticline as well as those of Indin and Yenan, but owing to the lack of continvity of observation this must remain problematical for the present, I am also unable to state positively whether similar dome like elevations are formed along the axis of the Minbu anticline and whether it is there that the petroleum occurs. The geological features in the neighbourhood of Minbu render this, (9 ) 142 NOETLING : PETROLEUM IN BURMA. however, very probable and besides there is no reason to suppose that conditions different from those of the Yenangyoung anticline should prevail at the Mínbu anticline, . We may therefore sum up our knowledge of the occurrence of petroleum in Upper Burma as follow : (1) The petroleum occurs in the miocene beds or Prome stage. (2) It has hitherto only been found along the crest of anti- clinal arches. (3) In preference to others, petroleum is found at such places along the above structurallines where the strata form dome-like elevations. (4) The occurrence of petroleum seems to be limited to a zone of about 40 miles in breadth which runs along the east- ern side of the Arrakan Yoma. These facts may serve as a guide when further search for oil is made. If only those localities are examined where at least one of these conditions is fulfilled, much money will be saved which will otherwise be wasted in fruitless search, From the foregoing we see that the occurrence of petroleum in Burma forms no exception from the well known rule of its associa- tion with anticlinal structure. It is superfluous to dwell here on this subject which has been so abiy discussed by Professors Hófer and Orton besides many others. It is sufficient to have shewn that in Burma the occurrence of petroleum conforms to those laws which regulate its occurrence elsewhere. | On the other hand it should be mentioned that the occurrence of petroleum in Burma seems a particularly good illustration of its restriction to dome-like elevation along the axis of anticlinals, a feature to which Professor Orton has already drawn attention.! | 1 Rep.on the Geol. Sur. of Ohio 1888, Vol. VI, 1888, page 99. ( 188 ) | і А F | CHEMICAL COMPOSITION. 143 CHAPTER VIL—CHEMICAL COMPOSITION AND PHYSICAL PROPERTIES. In order to arrive at a fair opinion on the chemical composition and physical properties of the Burmese petroleum it will be the best plan to review shortly all the papers that have dealt with that subject, and by summarising their chief results, we shall see how far the different analyses agree as to the composition of the Burmese _ petroleum. The earliest reference I can find, is Professor Christison's Analysis of Petroleum from Rangoon ;! the chief results of his analysis are as follows :— “ The petroleum of Rangoon, at ordinary temperatures in this country, is a soft solid, of the consistence of lard. Its specific gravity, at the temperature of 60° Fahr. is 880, water being 1,000. At the temperature of 86°, itis of the con- sistence of thin paste, and at 9o? it melts completely, and forms a sluggish liquid which acquires more fluidity as the temperature rises. Hence in the East, during the hot season, when it is dug for, it must be in the fluid state, and consequently entitled toits vulgar name ground oil. It has a powerful naphthous odour, differ- ent from that of most other petroleums.. * * * * * % ж * <“ When six ounces of petroleum were distilled, there was first procured, at a low heat, an ounce of nearly colourless naphtha ; then another ounce of straw yellow naphtha, then at a higher heat, about another ounce, much more yellow, yet still fluid at 60? Fahr ; next a considerable quantity of a yellowish liquid, «which con- creted at 60? into a loose mass, composed of numerous crystalline needles and plates, in a yellow naphthous fluid; and as the distillation went on, this matter be- came more and more solid, but even towards the end was not firmer in consistence thanlard. The residual matter in the retort, when the heat had been raised to ` full redness, was a spongy charcoal. “ The naphtha, when rectified by a second distillation over a lamp and then by a third distillation from me vapour-bath, is limpid and colourless, like sulphuric ether, and its density is 779." Professor Christison called the crystalline mass “ Petroline," the qualities of which he describes in detail, and then adds in an appen- dix, dated December 1834? (the original paper is dated February 1831), that having observed, from an account of Richenbach's dis- covery of paraffine in Buchner's Repertorium, that the properties of ! Chemical examination of the petroleum of Rangoon. "Transactions of the Royal ` Society of Edinburgh, 1836, vol. XIII., page 118 ff. a Transactions of the Royal Society of Edinburgh, 1836, vol. XIII, page 123. ( 189 ) 144 NOETLING : PETROLEUM IN BURMA, paraffine being obviously identical with those of petroline of the Rangoon petroleum, the latter name appeared unnecessary. The appendix Just referred to was apparently the result of a paper “ On the composition of the petroleum of Rangoon,' by William Gregory, published in December 1834, in which the author demonstrates that the properties of petroline and paraffine are identical, but, except this fact, not much further light is thrown on the composition of the Burmese petroleum!, About twenty years later Messrs. Warren de la Rue and Hugo Muller ? published the results of their examination of several tons of Rangoon tar, but it cannot be said that these were particularly satis- factory. According to these authors Burmese petroleum possesses the following qualities :— * At the common temperature this substance has the consistence of goose fat ; it is lighter than water, has usually a greenish brown colour, and possesses а slight odour, peculiar, but not disagreeable ”. The authors found that by submitting it to fractional distillation yielded?— at 212 F. (тооС.) . : 8 5 А 11 per cent. volatile oil. between 230° and 293°F, (110? to 145°C.) . " IO ور‎ Т » 320° to 617°Е. (160° to 325°C.) : Ai: F, heavy oil, at 617° F. 325°C. . B ° ° ° 31 » » э above 617°F. (=325°C.) . . . еі! az » ” ” Asphalte and coke ° ° . . 7 » 5 M The authors then analysed the liquid portions of the distillate and found that Burmese petroleum contained at least the following hydrocarbons :— Benzol - А : = ° Е Es Hç Toluol ° . ° š ° . C, Ha Xylol AS : Ф А : Es Hs Cumol - e ë 4 в E €. Ha 1 An abstract of the papers quoted above is given in Journ. Asi. Soc. Beng., Md Рр. 527. š 2 Proceedings of the Royal Society of London, 1857, vol, VIIL, page 221 ff. š The authors state that the temperature may be raised to 320°F. {= 160°C) without - materially altering this percentage, we may therefore suppose that the next fraction dis- tilled above that temperature. ( 190 ) - gravity of this native petroleum was о" 875 at 29°. CHEMICAL COMPOSITION. 145 In Schaedler's Technologie der Erdóle! another analysis of ' Burmese oil is given, and the name of the analyst as H. Vohl. The Rangoon oil? is here described as follows: “Farbe, grünlich braun; Geruch, eigenartig, nicht unangenehm; Consisteur, von Gànsefett ; spec. gew. 0'885—0'890o." It contains :— Leichte ól : А * Е e ы Е 41740 per cent, Paraffin masse : : = : ° 5 5090 T clan. e as 4'60 » Wasser und gas : Ё А : DM s 2°80 » Verlust . . . . A “ . 3 0'30 m MENOR kame oil contains — Photogen ° . ° ` x Б a 40°70 per cent, Schmieról . ° . e e ° "m € 40°90 ” Paraffin х А А м % . А 6*20 м; Asphalt . ^ 4 . ° - e. š 4°60 " | Verlust . = Е к - А ° Е 7°6o " In 1865 Messrs. Warren and Storer? examined some sainples of petroleum from Burma which they describe as follows :— _ ** Upon examination the petroleum was found to be a thick, greasy matter, not sufficiently liquid to admit of being poured from the can which contained it when the temperature of the air was 25°C., but upon being heated, it flowed readily at 30°—33°, and became perfectly fluid at 38°—40°. The color of the mass was yellowish green. It emitted the odor common to the purer varieties of native petroleum ; though the odor was but slight and in nowise offensive. The specific о 22 When distilled and heated up to 300°C., 30:46 per cent. of volatile product, or naphtha as it is called, were obtained. This naphtha was further examined and contained : Co Hj . . : . Rutylene, distilling from 170” to 176° Д азе ? » » 180! to 184° Са Haz . . . ° Margarylene ,, „o 186° to 193° Cu Hy . с = - Laurylene ,, ,, 200° to 214^ Co Has ° . . 2 Cocinylene ,, » 226° to 234° CH. -+ z e hs Naphthaline. It probably also contains Pelargone С, H,g boiling at about 155°. 2 Technologie der Fette aund Oele vol. II, Techn. d. Fette und Oele der Fossilien 1877, page 108. ? Examination of naphtha obtained from Rangoon Petroleum. Memoirs of the . American Academy of Arts and Science, Cambridge and Boston, 1867, new series, IX, p. 208 ff. | L | | ( 19: ) 146 NOETLING: PETROLEUM IN BURMA. Although it is quite probable that for commercial purposes numerous analyses have been made, no further analyses of petroleum from Burma have been made and published in scientific papers so far as I know, up to 1891 when I sent a series of samples of petroleum which I had collected at various places and depths in the Yenang- young oilfield to the laboratory of the Geological Survey, where they were analysed by my colleague Mr. T. H. Holland. Mr. Holland has published a very elaborate paper on the results of his examina- tion in the Records of the Geological Survey 1 to which I refer the reader. Quite lately Professor Engler? has published the results of his examination of petroleum from Burma which was collected by me at the Yenangyoung, Yenangyat and Minbu oilfield by which further in- teresting details, especially as regards the commercial value of the Burma petroleum, have been elucidated. | It now remains to group the results of these various examinations, which extend over a period of 6o years in such a way as to arrive at as complete a view on the physical and chemical qualities of the Burma petroleum as can be given at the present moment. It must, however, be kept in mind that this abstract does not pretend to be exhaustive, because, notwithstanding the various examinations, very little is known as to the finer constitution of the crude petroleum for reasons which may be explained easily enough. Analyses of this kind require a large quantity of crude petroleum, collected and her- metically sealed at the place of production. It is quite intelligible that owing to the high temperature of central Upper Burma and the length of transport to Europe, a considerable quantity of the more volatile oils must evaporate before it reaches the hands of the analyst, if the above precaution is not taken. Hitherto only small quantities could be collected under these conditions, and even the analysis of ! Records of the Geological Survey of India, 1891, XXIV, page 251 ff. E » p " 1894, XXVII, page 49 fi. ( 192 ) , a е » COLOUR. | 147 those, as far as they have been carried out in Calcutta, have been seriously influenced by the climate.! As regards the locality from which the material for the older analyses was obtained I am certainly not wrong if I maintain that it came from the Yenangyoung oilfield and not from Minbu or Yenan- gyat, for reasons which are obvious. Minbu hardly produces any oil, and the Yenangyat production has upto a recent date been so insigni- ficant that it was consumed locally. Colour.—By transmitted light the crude petroleum shows various shades of brown, changing from dark chestnut to almost black; by reflected light the colour is a dirty dark green. All the examiners of Burma crude oil agree in this respect, and to my knowledge there is no exception as far as the petroleum from Upper Burma is concerned. Perhaps there are different shades of dark brown, at different localities, but they are so imperceptible that they may be overlooked, | Specific Gravity—In the following table I give the figures regarding the specific gravity of the “ Rangoon Oil” as it has been ascertained by previous examiners :— | Name of examiner, Name of locality. Spec.G. Temp. 1830. Prof. Christison Yenangyoung oilfield ‚ 0'880 60°F. H. Vohl о" 885--0'890 1865. Messrs. Warren and Hofer A ` o'875 84°F. 1891. Mr, Holland Kodoung Мо. 1 0'875? 85°F » | » No. 16 0'887 ” » m 'No. 13 0'879 » » Twingon No. 310 0°863 » » Т - Мо. 306 0'865 n » » No. 374 0'872 " » Beme No. 504 0'887 ” » » No. 516 0'892 si 1 Records of the Geological Survey of India, vol. XXIV, page 251. 2 B. Redwood, Cantor Lectures on Petroleum and its Products, 1886, page 16, states that the sp. gr. of oil from Minbyin (Burma) is 0'866. No such place is known to me, but it is very probable that the name of the locality is misspelt. L 2 ( 193 ) 148: NOETLING: PETROLEUM IN BURMA, 1894. Prof. Engler Kodoung No. 26 0:8726 89°F. Twingon No. 62 0°8653 » i5 - Yenangyat No. 15 0'8214 » М " (mixed) o'8r6o ` » ^ Minbu 11002-3 806%. From the above figures, it is quite obvious that the petroleum of the three localities, Minbu, Yenangyoung, Yenangyat, differs consider- ably as regards the specific gravity. The Minbu petroleum is ap- parently the heaviest, its specific gravity being 1002, then follows Yenangyoung with an average of 0:878—0:869, and the lightest oil is apparently that of Yenangyat having a specific gravity of only о” 819. On the other hand we see that the specific gravity of the petro- leum from one and the same petroliferous tract varies considerably. According to Mr. Holland the specific gravity of the petroleum from Yenangyoung varies from 0'863 to 0'892 at 85:5? F. After having ascertained that the petroleum occurs in different beds entirely separated from each other and apparently without any communication, the idea occurred to me to inquire whether the un- questionable differences in the specific gravity, are due to the differ- ence of occurrence, in other words, whether the petroleum from. the: different oil sands is characterised by a different specific gravity. For this purpose I have made a series of observations which require, however, a few words of explanation, All the. observations. were made with petroleum specially drawn from the wells. In manv cases they were repeated because the heavier oils congealed so quickly at the temperature of the. oil (72?) that in one instance, that of well No. 135, I noticed the specific gravity change within a few minutes from 32°B. to 38°B,, simply from the hydrocarbons of low melting point becoming solid at the above temperature. With regard ‚to the drilled wells another matter makes ob- servation on the spot extremely difficult; the oil is pumped up, it is therefore so saturated with air and gas,that the bubbles which form on the surface, after the oil is freshly taken from the well, are a very serious obstacle to exact observation, and if in order to avoid this. X 104; ) SPECIFIC GRAVITY, 49 the oil is left standing е some time, the temperature changes, so that this forms a new source of error. ` Î have arranged these observations into four tables according | to the cláss of depth to which each well belongs, the drilled wells are Ee in a separate table :— UM | L— Wells below 151 feet іп depth. | a ЕГІН Sm [^ жайы; | 8 үш 87 257 0'0210 20917 87 235 2070120 079228 89 19 079395 09511 88. ‚22 | 0'9210 0'9322 86 19. 979205 09499 AVERAGE — j| — 09147 0'9209 /1— Wells from 151 to 200 feet in depth. Depthin | ` Temp. of Density feet. —— oil °F. em. eo Spec. G. Viet у 155 86 1б 0'9589 | | 0°9695 156 ^ . 88 | 16 09589 0'970t i ror 86 22°5 о0180 079284 165 87 | 16 | 09589. 0:9697 3 OO 87 165 0.9556. 0:9664 "yi 88 ` 26 | 0'8974 . 0'9086 185 87 6 . 09589 079697 188 | 87 ` 23 079150 070258 189 - |. 89 O27 5 08750 . 08874 3492 3 | | Ss un | 1б 070580 Ein 0:9689: poc UENIT MU [ "jeg авза ожо des ж | саз 09655 — 09763 " 200 : i | 89 4 31 98695 | 08811 AVERAGE | 0'9279 | 070465 : б A M $n ы yir Де, i je e "o W A CAMPER: HEN EN ы hs Hrs айақ” АТЫНАН 70% АЛТ ё — m 150 NOETLING: PETROLEUM IN BURMA. ]11.— Wells from 200 to 250 feet. 307 205 89 305 08721 0°8837 G118 205 90 31 0:8695 0'8815 208 206 87 30 0'8750 0:8858 707 210 88 23 070150 679262 16 224 86 18 070459 079563 255 229 92 305 08721 0:8949 273 233 89 31 0'8695 o'8811 442 258 90 28 0'8860 o'8g8o 91 240 go 28'5 08833 08953 227 241 80 31 08695 0'8811 170 242 90 3I 0'8695 0'8815 121 242 88 28 о:886о 0'8972 619 244 88 I9'5 0°9364 0:9476 11 246 87 | 215 0'9240 0'9348 23 246 | 86 215 0'9240 0'9344 107 248 88 35 08484 08596 65 250 85 dE о8605 08705 AVERAGE | 08891 0'9011 IV.--Wells from 251 to 300 feet. Serial avr | up rT 280 251 |. go 20 0:8805 met 469 251 90 26 08974 070094 115 255 | 87 33 о'8588 | 0:8696 ——-— J ———"nFn E yU NI "UA aa Tu 7 SPECIFIC GRAVITY. 151 — Wells from 251 to 300 feet—contd. Spec. С. Rai Us 08774 0'8886 0:8588 0:8700 0:8833 08953 0'8695 0'8815 o8641 7 08753 0'8641 08761 0'8641 0:8745 09333 (09421 y o'gogo 079202. o'gogo 0'9182 о8605 08810 0°8641 -0'8753 | 0'9271 070371 | 0'8974 0'9098 08833 0'8957 0:8641 08733 08605 0:8811 08805. o'8921 -0'8805 0'8921 0.8641 08761 08695 08810 : AVERAGE | | 0876 о8921 — ( 197 ) COME" ER | Mas " LE ^ | | Я V A y r " A e uno m P. RAR 29: d ALS N MV I r y 152 NOETLING: PETROLEUM IN BURMA. V.— Wells over 300 feet. age care р їп T ky cd өріс, Gy Spar, 5 at 249 3o3 9o 29 | 08805: о8925 167 303 86 33 0'8588 0:8692 359 312 91 285 |“ 08833 0'8957 AVERAGE ї 0'8742 0:8858 | Oo: РІЛ шй 18 337 89 34 0:8556 0'8652 II 395 88 29 0'8805 0:8917 47 353 87 29 0:8805 08013 20 220 88 30 0'8750 0'8862 6 345 86 34 0:8536 0'8640 46 356 85 26 0'8974 0'9074 I 727 88 30 08750 o'8862 22 317 8o 205 08774 o'88go 53 365 89 35 0'8484 о'8боо 23 422 87 10(?) 1(?) 1(?)* AVERAGE (No. 23 EXCEPTED) . o'8712 0'8823 Looking through these tables we observe that the specific gravity of the petroleum of such a small area as the Yenangyoung oilfield | * The specific gravity of this oil could not be ascertained at the temperature of 87° _ which it showed. When coming out from the well, it was a semisolid of the consistency of butter. | bi 198%.) “ SPECIFIC GRAVITY. I53 oscillates within very wide limits. Even if we disregard for a mo- ` ment the semisolid oil obtained from Kodoung well No. 23, in which the hydrometer stuck, we see that the specific gravity varies with- ` in the limits :— o'g722 (88°F.) =0'9834 and (6o°F.) 0°8484 (89 °F.) =0'8600 and (60°F.) the former being observed in pit well No. 691, the latter in the Kodoung well No. 53. The Yenangyoung petroleum belongs therefore to the very heavy oils, a fact which has already been noticed by pre- vious observers. But the figures seem to demonstrate, that within the area of the Yenangyoung oilfield the heaviest liquid petroleum hitherto known has been found. The heaviest petroleum mentioned by B. Redwood comes from Barbadoes, and has a specific gravity of 0'957, which is considerably exceeded by several samples of the Yenangyoung oil. | | М” тау be mentioned, that the examination of these various qualities of petroleum have shown that the Yenangyoung oil forms no exception to Hófer's rule’, The lighter coloured the oil, the smaller its specific gravity. The oils of low specific gravity, exhibit in transmitted light a fine dark reddish colour, which changes into dark brown in heavier oils, and is almost perfectly black in the heaviest varieties. Among these 72 samples of oil, examined with regard to their specific gravity, we find that— | 7 7 or 9'8°/, have a sp. gr. . below 16?B. 6or 85 „ » m: above 2 16°B. but below 20?B. I2 Or 17'0 ,, " ” ” . 209В. n 25°B. 21 -OF 20°S , 5 ҚС » а БЫН; ^ 3o°B. 25 Or 35'1 5, » » » . 30°B 3 35 B. These figures seem to demonstrate, that notwithstanding the high specific gravity of some varieties of the petroleum, the very heavy oils are decidedly in the minority. Oil having a specific gravity between 0° 8750 and o: 8484, takes the largest share, but is 1 Das Erdol (Petroleum) und seine Verwandten, Braunschweig, 1888, page 29, ( 199 ) 154 NOETLING: PETROLEUM IN BURMA. closely followed by oil with a specific gravity from o' 0032 to о" 8750. | Turning to the specific gravity of petroleum derived from dif- ferent depths, the figures apparently prove that the oil becomes lighter with depth, as seen from the following table. The average specific gravity of oil drawn from the ` Ist oil sand (wells below 151 feet) is , 0'9147=0"9209 at 60° Е. 2nd „ 5 » from 151 to 200 ,, . 0'9279 — 0*9465 3rd „ „ a » 201t0250 „. œ 0'8891 =0"9011 6 5 251to300 ,, . . 0'8766- o'8921 c тоге than 300 ,, 4 0:8742 = 0:8858 d ,Kodoung wells ,, š 0'8712 =0'8823 Grand average of Yenangyoung oil . e 0'8917=0'9171 However, in going through each of the tables, we find that there are wide differences in the specific gravity of oil which apparently comes from one and the same geological horizon. The explanation is easy; in the pit wells the oil from the upper bed is not shut off when the well is deepened, but is allowed to filter into the well, where it mixes with the lighter oil of the deeper sand and the result is that the oil from the deeper pit wells is in many cases a mixture of oil coming from various sands, but still we can see that, whatever may be the origin of the very heavy oils in the deeper wells, petro- leum of lighter specific gravity predominates in them. In conclusion I may be allowed to say afew words on the prac- tical importance of the specific gravity of the oil. Since immemorial times the petroleum from Burma has been sold by weight; the standard being 1oo viss, equal to 365lbs. The production of the deep wells is, however, ascertained in a different way ; the oil is conducted into large iron tanks, the contents of which are daily gauged by a measuring rod, and thus the volume, expressed in | gallons, attained. The weight is obtained in the usual way, but it is of course quite clear that according to the specific gravity the most varying figures will be obtained. A certain average specific gravity will of course do for all practical purposes, but even that requires а ` certain amount of correction. Let us for instance assume the average specific gravity to be o 8917 at the y oe temperature ( 200 ) ООРТ ТҮР a >..." „ “АЕ LP ^ 215 1 SPECIFIC GRAVITY, 155 of 88?F., which the petroleum has when coming out from. the well, When this petroleum is storedin the iron tanks, the tropical sun heats itto a temperature of 100?F. and more, The oil expands, its specific gravity changes, and instead of being 0'8917 it will be 0'8869 at the temperature of 100%F.; in other words it will be lighter, and when the gauge shows that 16,000 gallons are in a tank, this quantity converted at the specific gravity of 0'8917 would give 89,170 lbs, while it actually weighs only 88,6golbs., that is to say under the above supposition, there would be a loss of 48olbs. on every 10,000 gallons owing to the expansion of oil under the influence of heat. Owing to the custom above alluded to, the quantity of the pe- troleum produced by the oilfields in Burma is recorded in Burmese viss. At the average temperature of the oil when coming fresh out of the well, and at the specific gravity of 0'8g17, one barrel of 42 gallons of crude oil would weigh 374'5lbs, As, however, owing tothe high temperature of the oil under the influence of the sun the specific gravity is smaller, say 0'8869, one barrel of crude oil will weigh 372'4lbs. For the purpose of comparison it is therefore quite correct to assume that тоо Burmese viss are 1 barrel of 42 ` gallons; and to convert Burmese viss into barrels, the last two figures must be struck off when the production is given in viss; for instance, 100,000 viss = 1,000 barrels, the error being 2°/, in . excess. Volatility —No special observations have been made with regard to the volatility of the Burma petroleum, but experience has _ proved that under the influence of high temperature, crude pe- troleum rapidly decreases in volume, Tank-flats which received their full load at Yenangyoung, show a considerable loss when arriving at Rangoon. pr When the petroleum is left to itself in the natural springs at Minbu, it gradually gets more viscous till it resembles asphalt. The high specific gravity of the Minbu petroleum may perhaps be accounted for by evaporation of the lighter oils. ( 20r: ) 156 NOETLING: PETROLEUM IN BURMA. Flashing Point and Boiling Point.—The following are the de. | terminations of the flashing point of the crude petroleum which have | been made :— Dr 1 Kodoung well No. 1 from feet depth . 60°F, (Holland) ж » » 0 16 FE 5» . 68°Е. - 3 » » » 19 » 359 » » ° 43^ B. э). 4 Beme s رر وو 100 „ 504 وو‎ Xm ka y » Mr. Holland states that owing to the difficulty in determining the flashing point of an oil which gives off inflammable vapour at a temperature much below that of the laboratory the flashing point of oils which flash below 73°F. was not determined except in two instances.! Professor Engler has ascertained the boiling point of several samples of crude petroleum with the following results— I Yenangyat well No. 15from feet depth boils at . 267°F, 2 » mixed sample » . 248—257F. з Kodoung well No. 26 from feet depth boils,,, . 275°—284°F. 4 Twingon » No. Gee " A BD iy: ben BOT 5 Minbu (natural spring) Š ¿A 572°F. Consistency and Melting point-—As regards the consistency, the Burma petroleum has been quite rightly termed a viscous oil. This quality is most probably due to its large percentage of paraffine wax. According to Messrs. Warren and Storer it represents a greasy matter, which Christison compares with lard, Warren-de la Rue and Hugo Müller with goose fat, at the temperature of 25°C. (=67°F.), I can fully confirm these statements ; during the winter months when the temperature of the air at Yenangyoung sinks to about 54°F, the petroleum which collects in earthen pots or small pools congeals and forms a greasy matter of the consistency of lard or goose fat. But when with the rising sun the temperature rises, it becomes liquid and flows readily enough at about 86?F. | This quality isa serious impediment to its being conducted by pipes over long distances, and if found in Europe or under a lower average temperature than that of Yenangyoung, transporting by pipe- lines would be out of the question. During the winter months the 1 Rec. Geol. Surv. Ind,, XXIV, p. 254 (1891). Р (2023) CHEMICAL COMPOSITION, 157 fios lines cool to such a degree, that if oil remains therein during the night, it congeals and so effectually TM the pipe that hours may lapse before it runs again. Lately Professor Engler has determined the melting point of several samples of petroleum from Upper Burma. According to him,— 1 Yenangyat well No. 15 melts at Š ° ; 78'8°Е. 2 » (mixed sample) ,, Ў . ° ° . 8rs"F. з Kodoung well No. 26 , ñ N : . -878'%F, 4 Twingon » No. 62 ,, ” ° . . 878 F, It would be rash to form a conclusion from these few data, but we may safely say that at a temperature below 75°F. the Burma petroleum becomes solid and forms a greasy matter like lard. The above figures seem also to indicate that the higher the specific gravity the higher is the melting point; however, with regard to this further observations are required. Chemical composition.—As already stated there still remains much to be done in this direction, because no detailed analysis has been made as yet. We shall therefore have chiefly to deal with the chemical composition from a commercial point of view. The only elementary analysis of Burma petroleum which I could find has been made by H. Sainte Claire Deville,! According to this - author * Huile de Birmanie (Rangoon)" of a specific gravity of '875 at 8274? F. consists of— . E. ° - i x x 3 м 838 H е 7 . . . . . . 12*7 O ° е ° . . . 35 100. According to Messrs. De la Rue and Miller ? the following members of the Benzol series have been found in the crude petroleum of Burma— Benzol . А . . : , En He Toluol . . ° . ° ° Cu Hg Xylol ° . . . ° . Cic H 10 Cumol К ° = ñ 4 ° Cis Hia 1, Comptes rendus, 1869, page 50o. 2. Proceedings of the Royal Society of London, vol. ҮШІ, page 225. ( 203 ) 158 NOETLING: PETROLEUM IN BURMA. In the table opposite those of the analyses of petroleum from Burma which could be compared are given ; for the last four I have. to thank Mr. W. Fox, Secretary to the Petroleum Association, ` London. Mr. Holland's analyses which have been carried out on a different principle could not be compared with them, but it seems that Mr. Holland generally obtained a much smaller percentage of illuminating oil than any other analysis. These analyses prove that the petroleum from Upper Burma contains from about 50 to 60 °/, illuminating oil; Professor Engler mentions however that specially constructed lamps would be re- quired, if a bright flame without smoke were desired. The percentage of lubricating oil is somewhat smaller, being about 50 °/, inclusive of paraffine wax, if we except the Minbu oil, which probably does not exhibit its original composition. The per- centage of paraffine wax ranges, according to Mr. Fox, from about 6 °/,to 14 ?/,. The approximate average of Burma petroleum would therefore be Illumigeting ol" и. Бре Lubricating oil А ° ° . ° до ° Paraffine wax ° ° . 4 ° 10 °/, It is unquestionable that the lighter oil from Yenangyat affords a larger quantity of illuminating oil, than the heavier oil from Yenan- gyoung. ( 204 ) = е ане š E > - аў P. Kr ра а Li ir mn Pe’ ~ — 22 uu 3 С Fe = 794 1% e m e a Das 3 е m - e 7 E. 2 . EN». РУ E M 159 CHEMICAL QUALITIES, "1,99 pa р = £ É ~ 4 ç t ` š ` * | ` | Py - Š F Р, « ° E | EEE posa. bow. "o A Sie ABO UMOR DUE S УЗ WI DUO M 5 [2.11 lar ["/,96.S Г "leo ( bi 4 хем әпшелед T of 9 “0.8? ch 09.08 “6.82 rd МІНЕ š ¿ES i сор 03 pue /,08 | °/,6¢ PJ ve (7,6% (| 906шо4 |" По Suneəouqnq ; ç ¿00€ NS °88© [885 1/96 [P/,b.6p ^[oc | Ost worg ° o BuneuruniI “ге ес | "IUS |< "hab >= | \ ww ees PER Pog: | 9.12 "3e [OSI MOS ° “ 5034317 ` j pir ge a x ier I VAR ¬ “iio ‚ эпо e o ti figa Ale r 3e Ms wooduey |uooBšueu А | | “Suns HO | ; oe}. |, IN Li MUN e yu s u» TW i а СР n n 160 NOETLING : PETROLEUM IN BURMA. PART III. ECONOMIC IMPORTANCE OF THE OILFIELDS OF BURMA, NOTE. vn otherwise stated all the quantities are expressed in Burmese viss. | I viss=3'65lbs. avoirdupois. 100 vissz 36 5lbs. oil of the specific gravity. 872= 1 barrel of 42 Imp. gall. To change viss into barrels strike off the last two figures. CHAPTER L.—THE YENANGYOUNG OILFIELD. SECTION I.— THE COMMUNITY OF THE TWINZAYOS AND THEIR | HISTORY, It is one of the peculiar features of the petroleum industry of Burma, that the right of exploitation of the famous Yenangyoung oilfield has from earliest times been in the hands of a corporation, It is difficult to say how the corporation acquired this right, whether by virtue ofa special grant by one of the former Burmese kings, or because its members were the first settlers, in this part ofthe country, who won the oil. However this may be, itis certain that the Twin- zayo community existed as far back as 1797. If we look up Captain Cox's description (see page 11) we find the following note referring to. the people who extracted the oil :— \ “The property of these wells is in the owners of the soil, natives of the country, and descends to the heirs generally as a kind of hereditament with which it is said the Government never interferes, and which no distress will induce them to alienate. One family perhaps will possess four or five wells. I heard of none who had more, the generality have less; they are sunk by, and wrought for, the proprietors.” | ( 206 ) ч, : à‏ کک HNIC THE TWINZA COMMUNITY. LUE Although Captain Cox does not use the term twinzayo, we may "conclude from the above description, that in 1797 a certain number | of families enjoyed a joint interest in the oil-wells, which were their property ; unfortunately Captain Cox does not give the number of families, but supposing there were 24 of them, each of which did not own more than 5 wells, the probable number of wells could hardly have exceeded 100, an estimate which agrees so well with my estimate of 130 wells (see page 178) that I can hardly understand how Captain Cox arrived at the number of 520 wells. Mr. Crawfurd also men- tions the twinzayo, but a more explicit reference to the twinzayos is made in Captain Yule's book, although he does not use the term twinzayo, but in a few short but clear sentences he defines the chief rights and customs of the community. He says:— | * The wells are private property, the ground they occupy being owned by 23 families, inhabitants of Yenangyoung, and the representatives, it is believed, of those who first discovered and worked the petroleum. They do not allow any stranger to dig a well, and although a respectable owner stated that they bad no written grant or confirmation of their exclusive privilege, yet it is upheld by the local Burmese authorities, and apparently they have sufficient influence to prevent. any welis being dug by interlopers in the vicinity of their groups or clusters of wells. The 23 proprietors constitute a kind of corporate body as regards their joint interest in the land, but possess individual property in their own wells, When once a well has been dug, no one else is allowed to dig within 30 cubits of it. No proprietor is allowed to sell or mortgage his well to any one not.a pro- prietor. They mortgage among themselves. Formerly they intermarried among themselves only.” ! In none of the subsequent descriptions of the Yenangyoung oil. field are the twinzayos mentioned, and except the legendary refer- ence to 24 families, the descendants of the myothugyi who con- structed the tank (see above, page 2), the two passages quoted represent the whole of our knowledge of the community of twinzayos during the past ages. It is only quite lately that the subject had to be taken up in con- nection with delimitation of the native oillands, and the following ( 20% ) M I62 ' NOETLING: PETROLEUM IN BURMA. chief rites and customs of the twinzayo community have been ascertained :— | . There are 24 families which enjoy the joint right to dig for oil in a certain not well defined area close to the villages of Beme and Twingon. They are called the yoya-families and every member . of them was entitled to dig for oil. A well owner must necessarily belong to one of these families; no outsider could therefore own à well. | | 2. The head of one of these families is called the twinzayo, and enjoyed the following privileges. . When a member of his family wanted to dig a well, he had to apply for the site to him. In re- turn for the grant of a site, the well owner (twinza) paid a small monthly rent, according to the quantity of oil derived from the well, to the twinzayo. He was, as well as other members of the family, exempted from the so called eight royal services, that is to say, he had not to do forced services or to pay any taxes. 3. The yoyas are divided into male and female yoyas, there being 18 of the former and 6 of the latter. Title and rights of a yoya descend strictly in primogeniture, the male yoya being solely in the male, the female yoya in the female line. The yoya could not be sold to an outsider, but if any twinzayo had no direct descen- dants, he could, with the consent of the other twinzayos, sell the yoya to a distant member of his family. It is known that at least four yoyas were purchased by junior members of Mr family, the elder branch having no direct heirs. 4. Among their number the twinzayos elected a head man called twinggimin, who settled disputes, and in later years gave the final permission for digging a well, for which permission he received a small fee. 5. The following customs were observed as regards the wells :— (2) No well was to be nearer than 3o cubits (= 48 feet) to a other already in existence. (^) No well was to be sold or mortgaged to an outsider, but | ( 208 ) kaq a. x m A | Қ | CONDITIONS OF TENURE, | 163 the owner could dispose of the oil obtained therefrom-in any way he pleased. 6. The members of the Yoya families formerly BAER exclu- sively amongst themselves. Such were their chief customs as they were described to me by several twinzayos, and corroborative evidence of the truth of these statements will be found in the two passages quoted above, but these rules have lately been much infringed upon. Even at the time when the members of the Mission to Ava visited Yenangyoung, com- plaints about this were made. Later on the customary distance between the wells was no longer observed and the wells were sold and mortgaged to outsiders. : A radical change took place when, about 1852, King Mindon Min perceiving the traffic in petroleum would prove a good means of filling his exchequer, declared the petroleum a royal mono- poly. Petroleum could therefore no longer be disposed of at the liberty of the producer but had to be sold at a fixed rate to the farmer who rented the output from the king. The Burmese King thus derived a very handsome revenue from the oil fields, which amounted to about R600,000 per annum between 1873 and 1881, but fell to about half the amount later on. Much interesting light is thrown on the transactions between the twinzayos, the Burmese King and | the farmer who rented the output of the oil fields by the letter quoted above (page 27). This letter is in fact the only document we possess regarding these transactions. It is quite intelligible that from the time when the right of dis- posal of the petroleum no longer rested with the producers, the other customs which had hitherto been strictly adhered to were infringed upon. A-good many outsiders now possess wells, who in former days could not have been able to own them. As it was, however, necessary that some kind of settlement should be arrived at, and the vested rights of the twinzayos be protected, a certain area near the villages of Twingon and Beme was reserved, after a prolonged ( 209 ) M 2 164 NOETLING: PETROLEUM IN BURMA, inquiry, and the well sites therein contained could be disposed of only by permission ОҒ a twinzayo. The wells, however, could be sold to any outsider, as well as the oil; not only have the rights of the Burmese diggers thus been protected, but a magnificent present has been made to them considering the limited extension of the Yenan- gyoung oilfield. | SECTION II. — THE CONSTRUCTION OF THE PIT WELL. Construction of the pitewells.—There can hardly be anything more striking, than to read the accounts written about a hundred years ago, describing the operation of digging a pit well, while watching the native miner of the present day digging a weil. There is not the slightest difference in the method of a hundred years ago and the present one, and Captain Cox's description could as well have been written in our days. | | Having selected a place, a square hole, the sides of which are about 63 to 51 feet, is dug; the walls are lined with a wooden casing, which consists of rough split wooden staves, notched at. either end to secure a safe jointing. Four of these staves, which answer in length to the length of the sides of the wells, form a square frame, These frames begin at the mouth of the well, and their number gra- dually increases as the well advances in depth by new ones being added at the lower end of the casing. It is estimated that for every 80 cubits (about 148 feet, the cubit being 22 inches) 1,200 staves are required, that is to say, 300 to each side; the average height of each frame therefore being about 5 to 6 inches; the = thickness is hardly more than 2 inches, but being well jointed the frame has sufficient rigidity to withstand the pressure of the sides, although it is common enough that, when the wood is allowed to get old and rotten without being renewed, the casing gives way and the well caves in. At present the price is Rio for roo pieces, It is hardly intelligible how an observer, otherwise so correct as Captain ( 210- ) CONSTRUCTION OF PIT WELLS. | 165 Cox, could have been deceived about the construction of the wooden casing as to state that the frames are added at the top, “ the whole regularly sinking" as the depth of the well increases. A short reflection would have shown that the friction between casing and rock must be so great that nothing whatever could force down the casing without its being broken. The tools used for digging are simple enough; they chiefly consist of a peculiar instrument called tayuwen, that is to say, a chisel shaped iron shoe fixed to a heavy . club shaped wooden handle. The iron shoe is round, slightly tapered and ends in a double pointed edge. The handle which fits into a hole at the upper end of the bit is club shaped and deeply notched about 6 inches from the upper end, The miner grasps the tayuwen at about half its length with both hands, the upper notched end resting against his shoulder and by put- ting the whole of his own weight in, drives the pointed edge into the ground loosening it and breaking off small lumps, which are after- wards removed by the hands, filled into a basket, and hauledup. |t is of course clear that the tayuwen can only be used in the softest strata, but as not unfrequently streaks of hard sandstone are met with, it remained a problem to me how the miners break through these beds, being deprived of the use of blasting power. During my recent visit I had a chance of seeing how the diggers managed to get through these hard beds, and I must confess it pays great cre- dit to the ingenuity of the Burmese well diggers. A prismatic lump of iron weighing about 1 so lbs. (40 viss) pierced at the upper end to allow a rope to pass, is suspended on a beam laid across the mouth of the well. The горе is then cut and the iron falls down striking the bottom of the well with such energy as to produce a consi- derable hole in the hard rock. As the fall of the iron is so directed that it gradually strikes every point of the bottom, the hard bed is eventually smashed, not however without great loss of time and trouble, as can be well imagined, for every time the weight has fallen down a man is obliged to go down and fasten the weight to the rope that it may be hauled up again. | IGI ) 166 NOETLING: PETROLEUM IN BURMA. Wages paid to the miners-—There seems to have been a - traditional scale of depth, in force since the last century, according to which the miners were paid, although the amount paid seems to have varied, and certainly has considerably increased since the annexation. The scale runs as follows :— (1) there isa fixed rate for the first 80 cubits (147 feet) of Rios to R120; (2) the next 10 cubits (18 feet) cost R35 to R45 ; (3) the next 10 cubits (18 feet) cost R55 to R60 ; (4) after the well has reached a depth of more than 100 ` cubits (183 feet) further digging is paid per cubit ; the general arrangement being that for 4 cubits of depth a fixed progressive price is allowed, ranging from R6-8-0 to R12; (5) after the well has reached the depth of 132 cubits (242 feet) another special arrangement comes into force of which I cannot say how farit is in general use; each miner receives Rio à month till the wellis finished, whether he is engaged in actual digging or prevented from doing so by circumstances outside his power; but when digging every man has to go down the well 20 times every day. 4 These data can be arranged in the following progressive scale :— Amount paid per cubit of 19 inches. Жо аф. А76 0. From oto Socubits А г 3 O чо le Q sn Be fo^ 7; 4 ЗИТ гө » 90 to OO ,, E 5.8 40: tau o" о GT LOOKS TED: vj а : 6-.8 0 PEDES O азоо 1202, ^. 1.2. Вака T Approximately. » 120 to 132 ,, . 12 оа | afterwards by special а As after repeated inquiries I always recelved the same figures, I believe that the above scale of progressive wages fairly repre- sents the actual amount paid to the diggers in 1890. The statements seem tobe the more reliable as they a are the same as givento me in 1888. k IA ) AA 4 - ^ MODE OF EXTRACTION. 167 The system is simple and ingenious, and it seems to me to have been based on along experience of the condition of the strata to be pierced. The fixed rate for the first 80 cubits seems certainly to ` indicate that the oil bearing sand was originally found at that depth and that only afterwards when the uppermost bed was exhausted did it become necessary to adopt a progressive scale, because it was not quite certain at what depth oilbearing sand would be met with again. No detailed information about the wages paid for digging will be found in any of the earlier accounts, than that of Captain Cox. According to his statements the progressive scale per cubit was paid after the first fixed 80 cubits had been gone through without oil being found. The . amount of 300 ticals paid for the first 80 cubits and 30 to 5o ticals per cubit seems so enormous that I hardly feel inclined to consider it as correct. There is a general agreement in the Burmese statements that the prices for digging have only quite lately risen, and that in former times the construction of a well was much cheaper, In my opinion itis not likely that a century ago the prices should have been more than three times of their present amount, it being generally agreed that they are now higher than in former times. Machinery used for hauling up the ой, etc.—lf anything has changed since the тоо years, it is not the machinery which is used for letting down the diggers to the bottom of the well and hauling up the oil after the well has been finished. “The machinery used in drawing up the rubbish and afterwards the oil from the well is an axle, cross- ing the centre of the well, resting on two rude forked stanchions, with a revolving barrel on its centre, like the nave of a wheel in which is a score for receiving the draw rope. ” ‘Thus runs the description of Captain Cox: “A rude windlass, mounted on the trunk of a tree laid across two forked stems is all the machinery used." With these words, about 60 years later, Yule describes the arrangements for hauling up the oil. Now, one should think that it is quite impossible to make a mistake in describing such a simple machinery, but strange tosay such a mistake has really occurred from Captain Cox down to (7243 ) 168 NOETLING: PETROLEUM IN BURMA, Dr. Romanis; everyone who gives a description of the machinery invariably states that the cross beam rests on “two ” forked stan- ‘chions : the woodcuts in Captain Yule's Mission to Ava, page 20, and Dr. Romanis's sketch, both represent two forked uprights. Now there were never two forked uprights, only one of this shape the second one was a simple post into which the cross beam was pegged, The reason for this arrangement is quite intelligible ; if there were two forked uprights the axle laid across them was liable to revolve. The friction between axle and supports not being sufficient to withstand the heavy strain of pulling up a man, the cross beam had therefore to be made immovable, and this was easily done by pegging it on one of the uprights. It is hardly necessary to describe here the machinery in detail, but for the sake of completeness it may be done. Two posts, one of which is naturally forked, are placed at either side of the well; a rude cross beam is laid across these stanchions in such a way that one end of it rests in the fork, while the other end is pegged on the second one. By this arrangement the necessary rigidity is obtained. Two smaller forked branches, serving as supports of a revolving cylinder, are pegged in the middle of the cross beam. The revolving cylinder is made of hard wood, axle and cylinder being made out of one piece ; ascore for guiding the rope is cut in its centre, When hauling up the oil a leather rope is used to which an ordinary earthen pot is fastened; this 1з lowered down and is hauled up, when filled by two coolies running down an incline. It seems that formerly “Jackered wicker baskets" were used, but they seem to have been superseded for a long time by earthen pots. These pots are of pecu- liar make, they are ball shaped, with rather a narrow opening at the top, the edge of which forms a kind of neck round which the sling of the rope is fastened. The pots vary in size, containing from 10 to 14 viss, even 16 viss, The same pots are used for carting the oil down to the river.! | The lowering of diggers is rather ingenious. For this purpose a strong rope, which ends i two slings, is used, the digger sits on | ' Lately these timehonoured pots began to be replaced by the prosaic but less fragile kerosine oil tin. | 214 ) WELL DIGGING. 169 these two slings by passing his legs through them, the knot being over his left shouider; to prevent shifting a thin rope runs down from the knot across the breast underneath the right shoulder _ to the back, where it is fastened to the right sling; a second rope is fastened round the hips. Ata given signal the coolies holding the other end of the rope gradually lower the digger into the well; the work of hauling him up again is facilitated by an inclined plane which the coolies run down, thus pulling him up more by their weight than by their physical strength; in lowering the weight of the digger assists the coolies coming up the incline. This arrangement neces- sitates of course a gangway to each well, which must be so situated as to facilitate the work as much as possible. There are often as many as II coolies used to haul up a single man, to whose weight of course that of the rope must be added. Any one unacquainted with the oilfields will be rather puzzled when approaching a well in construction to see the diggers lying around the well with their eyes closed or even tied up (fig. 9.) ('215 ) 170 ‚NOETLING: PETROLEUM IN BURMA, The solution is very simple; as the time of staying down in the well is very limited on account of the fumes, the digger would not have time, coming from the bright glare of the day, to get his eyes accustomed to the darkness in the well before he was going to be hauled up again. By having his eyes previously closed he is enabled to see when down in the well.! Before going down the digger puts a quaint cap made of palm leaves on his head to protect it against stones, etc., falling down | (rom the walls. The following are observations of the time taken to lower and haul up a man and his actual staying down. Of course the first depends much on the depth of the well, the second on the quantity of gas developed, the temperature, and last, not least, on the = physical strength of the digger. General rules can therefore not be established and it is sufficient to give the observations taken at a well of normal conditions. Well No. 71. Depth 220 feet (146 cubits). Time in seconds. ari Useful ti Observation, Descent, Period below. Ascent, Total. SE ES in per cent, Ist 43" 27" 80” 150” 18 ond . 45! 22” 105” 162" 13°5 3rd қ š 39" 18" 124" T" A JO qth . 39" 27" 127" 193" 14 Schu 27" аз” 148” 108” 116 6th ; 36" 23" 134” 193” 118 ы . 31 22" 150" 203" 10 Tu n н 5 "à 30" 36” r76” 242” TAS This table is instructive In several ways—firstly it shows that the total time required for lowering a digger and hauling him up 1 Within the last two years; the Bermans have hit upon an ingenious method of throwing reflected sun light by means of a small mirror into the well, in order to facilitate the work. I do not exactly know how the Burmans made this invention so to speak, nor when they first used it, but I know for a certain that in 1888 this reflector was unknown to the diggers. 6.216 ] | ` VALUE OF WELLS. 171 ` gradually increases, chiefly in consequence of the increased time required to haul the diggers up. We may put down this fact to the fatigue of the coolies, as the observations were taken about 1} hours before the day's work was stopped. But the most remarkable fea- ture is the exceedingly small percentage of useful time, namely such time as the man stays down in the well engaged in digging. It varies from 18 per cent. to Io per cent. of the total time, an exceedingly poor result; it may be that sometimes the percent- age of useful time is higher, but we may fairly assume that it is never more than 25 per cent, of the total. Of course this applies solely to wells which have reached the oil bearing strata ; in higher parts where the diggers are not troubled from want of breathing air a man may stay down for hours. But,taken as a whole, it is evi- dent that the process of deepening a well once it has reached the oil- bearing sand isa tedious process, accompanied by much waste of time. I never heard of any accidents resulting from choking, although the diggers sometimes come up apparently much exhausted and streaming with perspiration. | Approximate value of a well of average depth.—The data above will enable us to arrive at an idea as to the cost of a well of average depth under normal conditions. "This calculation will be found useful as a check to statements of the natives about the amount of money invested in the wells, and furthermore it will serve asa basis for the estimate of the capital value of the native oil fields. 7% А calculation of the probable cost of a well 120 cubits = 180 feet, and 150 cubits = 225 feet, will be quite sufficient. I. Estimate of cost of a well 120 cubits = 180 feet in depth : Ж (а) Wages for digging— 80 cubits at the rate of š " 4 қ 200 ` IO cubits at the rate of . . . . 4 45 Io cubits at the rate of . - ° ° ° 6o ло cubits at R7-9-o рег cubit . : 75 10 cubits at Rio per cubit . . - ‚оо TorAL 400 ( 217 ) 172 NOETLING: PETROLEUM IN BURMA. E (2) Timbering— : 1,800 wooden staves at the rate of R10 per 100 4 180 (с) Machinery, ropes, etc., say . . ° . Te 30 GRAND ToTAL . 610 2. Estimate of cost of a well 150 cubits — 225 feet in depth: (а) Wages for digging— 80 cubits for . а . . . : ° 120 Io cubits for . А . 5 : А ° 45 IO cubits for : 5 : А : . 60 Io cubits at R7-8-0 рег cubit . . . 75 Io cubits at Rio per cubit . ы ° . 100 10 cubits at R 12 per cubit š . " ° 120 20 cubits under special arrangement, say R20 per cubit 4 š : К Й Й : 400 . TOTAL -^ 2626 (5) Timbering— Say 2,400 wooden staves at Еторег 100 . 4 - 240 (c) Machinery, ropes, and other accessories А . ° 30 = GRAND ToTAL . 1,190 Rn... We may therefore assume that an estimate of R1,200 for a well | up to 250 feet will be very near to the mark. SECTION Ill. —THE NUMBER OF WELLS IN THE NATIVE RESERVE. A. Period previous to 1888.—1f we look through the earlier ac- counts about the oilfields we notice a remarkable uncertainty about the number of pit-wells in the Yenangyoung oilfield. This might of course be expected as none of the previous visitors had time enough to go through the tedious task of counting the wells one by one. This was only achieved by the survey, during the years (+ ат V | ет? rM < ay Do 9% A NUMBER OF WELLS, 2173 1890 and 1891, and | am therefore in the position to check with some accuracy the statements of my predecessors. It is clear that the highest number of wells ever in existence must have been recorded by this survey, because in addition to new wells there were all the old wells which must have been seen by previous visitors, and I do not think that a well of, say, about roo feet in depth can disappear without leaving any trace of its existence behind. It is true some of the old wells have been perfectly filled . up again, but by various signs (soil soaked with oil, etc.) it is easy to see that a well once existed where there is now only a shallow hole. Now if we know, approximately even, the age of each well, we shall be able to fix with some amount of confidence the possible number of wells at à certain period in the past. It is, however, difficult to say how far the statements about the age of the well are correct, and to provide for a possible mistake I have allowed a fair margin of age for each well, dividing the wells accord- ing to their age in six classes, namely, — ° (a) wells of 5 years of age and less, (4) wells of то years of age and less, (c) wells of 20 years of age and less, (d) wells of 35 years of age and less, (e) wells of 50 years of age and less, (f) more than 50 years of age. This classification should answer for all purposes. The first class will show all wells dug since the annexation, and after deducting the ` mumber of wells in the first two classes we should have the number of wells existing during the period to which the letter of the Burmese Minister refers; the deduction of the first three classes should show the number of wells at Captain Strover's time; and the four Grst classes being deducted we should find the number of wells in existence at the time when Captain Yule visited the oil-fields. . The following table will show the number of wells in each ( 219 ) 174 NOETLING : PETROLEUM IN BURMA. class for the Yenangyoung field as a whole and for the Twingon and Beme tract separately :— Table showing the approximate age of the pit wells in the Yenangyoung oil field, Age of well. Less than 5 years Less than 10 viis Less than 20 years Less than 35 years Less than 5o years More than 50 years According to At the end of 1890 Іп 1888 . : juges а In T8270. uU. In 1855 . ‚уз Previous {о 1855 this table there were— ------------------1--------------,----------- Twingón, ^ 478 . 360 ° 330 А 168 . 152 . 143 NUMBER OF WELLS, Twingón. Bemé, TOTAL. 118 12 130 30 6 36 162 31 193 16 5 21 | 9 3 12 143 . 107 250 Bemé, TOTAL REMARKS., 164 642 Including wells under | construction. 152 512 146 476 IIS 283 110 262 е 107 250 It must of course be understood that these figures do not pretend to express the correct number of wells in the year referred to, but that they must only be taken approximately. Now the following (ew pa" NUMBER OF WELLS. 175 table will show the number of wells as estimated by different visitors in the years referred to— | Table showing the number of wells as estimated at different times, Year. - Name, dapi of REMARKS, 1795 . » - . | Colonel Symes , : 500 1797 « . > . | Captain Cox 3 А 520 1826 . x . + | Mr. Crawfurd ^ : 200 38539 © , 4 А . | Captain McLeod , 5 1бо Productive , wells mess. . Р : Dr. Oldham . à А 200 Bee 1855 . ` . . | Captain Yule ; 4 130 Ditto. | 673. қ à . | Captain Strover . В 150 1874 ` Ў ы „| Dr. Friedláender . 4 450 1879-81 . Ше . | Burmese estimate . і 226 1886 . i М . | Sir Charles Bernard К 343 EMG . . l Dr. Romanis a : 260 Ditto, With the help of these figures given above we see that Colonel Symes' as well as Captain Cox's estimates must be wrong, although their concordance seems to speak for their correctness. But we know that in the beginning of 1891 there existed 642 wells altogether. We further know with absolute certainly that 130 of these wells were dug within the last five years, and we further know that at least 120 wells (the so called Royal wells) cannot be older than 30 years. It is even stated that they are not older than 17 years. We know therefore for a certain of 250 wells which are not older than 30 years; most likely, however, not older than 17 years. We would therefore arrive at a number of 392 wells at the utmost on or about the year 1860, that is to say, in round figures 110 wells less than the estimate of about 70 years ago. We would, therefore, (eee) 176 NOETLING : PETROLEUM IN BURMA, be obliged to suppose not only that no new wells were dug during this long time, but that at least 110 wells had disappeared without leaving a trace behind, suppositions which are more than absurd. Both estimates must therefore be considered as highly exaggerated. As regards the next statements from Mr. Crawfurd downwards it is difficult to say whether the figures given represent the total of wells or productive wells only. It may, however, be considered : that the figures given by Captain Yule, Dr. Oldham, Captain Strover, and Dr. Romanis represent only the number of productive | wells, as their calculations about the quantity of the production is based on the stated number of wells. As it is, however, very unlikely that there were no unproductive or abandoned wells in existence in those days the total number of wells must have been larger. We shall, therefore, have to find out the probable total for the respective years to be able to compare the figures. Now in 1888 the ratio between productive and unproductive wells was 53°4 to 46:5, and I do not think it is unfair if we suppose that the same ratio existed in 1855, as it is only quite lately that it has shifted more in favour of the productive wells, ` Under this supposition the following table will show the pro- ЪаЪ humber of productive and unproductive wells in the year mentioned :— —— — ———— Number of un- Number of pros : Year. Name, | pls codo pore ToTAL. 1855 - . .| Dr. Oldham . А . 200 174 374 1855 ë . . | Captain Yule А . 130 113 243 1873 - + SI Captain Strover | s 150 130 280 1886 Dr. Romanis ° . 200 174 374 Now let us compare these figures with those theoretically ob- tained. I estimated that there were about 230 to 262 wells in 1855. From the above table we see that if Captain Yule's statement of the ` 4^5 222 7 NUMBER OF WELLS, 177 number is amended a possible number of 243 wells existed in 1855. ' This figure agrees so well with my estimate that if we suppose that there were 250 wells, productive and unproductive, we will be very near the mark. Dr. Oldham's estimate of 200 productive wells, _ which would give a calculated total of 374 wells, is undoubtedly too high; because if we add to this number the number of Royal wells and wells dug since 1885 we get a total of 624 which would mean thatsince 1855 till 1885 no new wells, except the Royal wells, were constructed, As we know, however, that during this period at least 120 new wells were dug, and if we add this number to the above 624; we geta total of 744 wells supposed to be in existence in 1890. As there are, however, only 632 we see that Dr. Oldham must have overestimated the number of productive wells. Now having arrived at the conclusion that in 1855 there were _ hardly more than 250 wells in existence we may fairly assume that the number of 200 as given by Mr. Crawfurd represents the total of wells, which were 107 productive and 93 unproductive wells, and supposing further that the same rate of progress existed during the period 1797 to 1826 as from 1826 to 1855, the probable number of wells at Captain Cox's time was something like 130, of which 70 were productive and 60 unproductive wells. | The number of 280 wells arrived at by taking Captain Strover's statement of 150 productive wells as basis for the calculation agrees so well with the figure arrived at by theoretical speculation that we may take it as accurate as possible. | | Dr. Friedlánder's statement of 450 wells made only a year later seems hardly to harmonise withit. We shall, however, see that the apparent disparity is the evidence of the correctness of this state- ment, and on the other hand strongly supports the statement of the natives that the so called Royal wells were dug between 1873 and 1874. | If we suppose that Captain Strover's figure applies to the number of wells previous to the construction of the Royal wells, and if we further suppose that Dr. Friedlànder visited the oilfields after their N ( 223 ) \ 178 NOETLING : PETROLEUM IN BURMA. construction, and if we add to their number (120) that of total num- ber according to Captain Strover, namely 270, we receive 390, say 400 wells, a figure which is pretty close to that given by Dr. Fried- lander, | The next estimates, that is to say, those of the Burmese Minister (336 wells), of Sir Charles Bernard (343 wells), and Dr. Romanis (374 wells) are undoubtedly too low, because I ascertained at the time of my first visit the existence of the old numbering of the wells which may partly be seen still, according to which there were at ` least 538 wells. It has been stated that the numbering was done immediately after the annexation; however it may be, whether it was done in Burmese times or later, the figure of 538 wells agrees so well with the number of 512 wells, theoretically supposed to be in existence in 1885, that the two statements referring to the number of wells in 1886 must be below the mark, which applies probably also to the statement for 1879-81. The number given by me in 1888 is also a little too low, as I confess that I must hàve overlooked some of the abandoned wells, The following table will show the probable number of wells in existence in the years referred to, those figures which are calculated being marked by*:— Table showing the probable number of productive and unpro- ductive pit wells in the Yenangyoung oilfield during different periods. Number of Number of | + Year. productive unproductive о мәле 1 795-97 . . . E e ° e 70" 60* 1826 RE Cat U Ta EDEN 107* 93* 1 855 ° ° . ° ° ө ° 1 30 11 3* 1873 > ° А А ° . " < 150 . 130% 1 874 ° ° . ° ° ° . 2 14 . 186% 1885 š . x А ° "me c 245 289* š OMM MPO TREE E EE Lo ELE DIO „сезде gt Ч 1 " - NUMBER OF WELLS. | 179 B.—Frow 1888 to the beginning of 1895. When I first ` examined the Yenangyoung oilfield in 1888 no map of this area was in existence, in fact we may say that this tract was almost a terra incognita. “To arrive under such circumstances at a fairly correct idea regarding the number of wells, proved a difficult 2 task. І was obliged to prepare а тар first, which was бопе by pacing and measuring the angles with the compass and to enter on this map the position of the wells. To increase the difficulties under which my work was carried out was the unsettled state of the country, I may therefore have overlooked some wells, but on the whole I think the number given is fairly cofrect. - During the year 1890-91 a thorough survey of the Yenangyoung oilfield was undertaken, during which the greatest care was taken to ascertain the number of wells in existence, and the locations of those which had been abandoned and were eventually filled up. The wells were carefully numbered and their positions accurately fixed, Generally we may divide the wells into two classes, productive and unproductive, and although the former are those of economic value, the study of the latter is not without interest, inasmuch as it reveals some features of the evolution the petroliferous tract has taken. The productive wells require no further definition, but a short explanation is necessary as to what I regard as unproductive wells. The foremost among the latter class are of course such wells as once yielded petroleum, the supply of which has run so short that they have been abandoned. By want of care the casing broke down and the walls sliding, eventually funnel shaped holes were formed, which in many cases have been entirely filled up again, The second in importance are wells under construction, vzz., wells which have not reached the petroliferous sand, but which are energetically deepened. Such wells are apt to become a most important factor in the future, although not productive at the time. The third class are well sites, ze, places which have been selected for the future location of a well. The owner of sueh a well N 2 ( 225 ) 180 | NOETLING : PETROLEUM IN BURMA. site may not. avail himself for the moment of his privilege, but at апу time he has the right to dig a well at the spot selected, and for this ‘reason the well sites were also recorded. They may or may not become an important factor in future with regard to the production. The following table will show the number of wells for the years 1888, 1891, 1895, 1895, but it must be remarked that no record was kept in 1888 of well sites or wells under construction :— | 1888. 1891. 1893. | 1895. Productive wells `. ° ° А 8 . 281 377 406 519 . E Abandoned wells lise 5 А 245 235 234 239 ou 5% Wells under construction ° ° . ves 32 23 151 E Well sites . қ ° ` š . u. 133 114 281 TOTAL А 526 777 777 1,190 . It will be convenient to deal with each class of wells separately and to examine the changes it has undergone during the period from 1888 to 1895. | | A.—Productive Wells. | In 1888 I recorded 281 productive wells, and although I may have overlooked some abandoned wells, I am quite certain that the above figure represents the actual number in that year. Since that time the number of productive wells has been steadily on the increase ; but it seems that the number increased by leaps and bounds rather than by gradualprogress. This is easily explained, as between 1888 and 189r the native well diggers were allowed to go on digging new wells,while in 1891 the construction of new wells was pro- hibited, pending the settlement of the rights of the Twinzayo Corpo- ration, and only those wells which were actually under construction in that year were allowed to be finished. Owing to the complicated nature of the rights in the native oilfields the period of settlement 2326-41) DEPTH OF PIT WELLS, 181 was a prolonged one, and during its duration only such new productive wells could be added as had been under construction at its commence- ment, This explains the very small increase of 29 productive wells during the period 1891—93. At the end of 1893 a satisfactory settlement of the rights of the twinzayos having been achieved the construction of fresh wells was again permitted, and the natives availed themselves of their privileges in such an energetic manner, that between the last half of 1893 and January 1895, 113 new productive wells had been constructed. So far this seems to indicate a very prosperous state of the native oilfields at present, but we shall see that far from being so, this very increase of the number of the productive wells is an indication of the setting in of the decline of the native petroleum industry. The pit wells may be examined in two ways, viz. :— (1) with regard to their depth, (2) with regard to their production, both sides will give us full information as to the state of the native oilfields, 'and if thoroughly gone into, some conclusions may be drawn which have been further elaborated in the section dealing with the future prospects of the oilfields in Upper Burma. (a) Depth of the pit wells. „It is a general belief among the native well diggers that a well sunk in one of the ravines which intersect the oil tract of Twingon reaches the petroliferous sand within the same depth as a well constructed on the plateau. On the face of it this seems highly absurd, as one would feel inclined to think that a well in one of the ravines being so much nearer to the petroliferous sand must strike it sooner than one on the top of the plateau. It is, however, a fact that such is really the case, and may be ex- plained. Observing that the Twingon tract is situated on the arch of an anticline, and that the area was mostly intersected by longitudinal ravines, 7.e., such running parallel. to the strike of the strata, the ` curious phenomenon seems to be easily explained by the natural dip of the strata, ' (` 227 ) 182 ^ PNOETLING: PETROLEUM IN BURMA. I have adopted this view in my former two papers, but I must €onfess that it never fully satisfied me, as there were many cases which seemed to be opposed to this view. In the geological descrip- tion I have, however, demonstrated the existence of three successive oilsands, and the restriction of the two upper ones to a very limited area, The wells in the ravines, therefore, most probably did not touch the ıst and 2nd oilsand at all, or if they did, they were not oil- bearing, and the diggers had to go deeper till they reached the level of the 3rd sand. It must therefore be supposed that two wells of the same depth, one being situated on the plateau, the other in the ravine, draw their oil from two different oilsands, following each other in vertical position. Of course the natural dip of the strata must not be entirely disregarded, as itis almost certain that a well situated farther from the centre of the anticline will traverse the , strata diagonally, and thus reach a given horizon at a greater depth than if constructed on the axis of the anticlinal. The greatest depth I recorded in well No. 411 was 317 feet from the surface, It seems almost certain that this represents the maxi- mum depth to which the Burmese well digger is able to go. The noxious gases at that depth render any length of stay in wells without artificial ventilation impossible; but even if the Burmans were to resort to this, the crude way in which they would certainly carry it out would prove most ineffective. Besides the long time which lapses in hauling up a man from that depth by the usual Burmese method, is so considerable that it would prove very expen- sive to deepen a well of over 300 feet only a couple of feet. As the return is also very uncertain very few wells have reached a depth beyond 300 feet, and we may take it almost for granted that 320 feet is the limit to which the Burmans can go with their method of digging. | The practical importance of this fact is obvious, and conclusions which may be drawn from it have been already dealt with in a previous section. | I found it convenient to divide the wells into five classes, accord- ing to the depth which they have attained, —such a division would be ( 228 ) | т ы. — ы» X oU , ` Cu ñm OBRA sd p o 1 DEPTH OF WELLS. m? perfect if we were able to refer all the wells to a common level, a task which is, however, almost impossible, unless the most careful levelling were resorted to. As the case stands, a well which is situated in a ravine-and which is, say, 200 feet in depth is classified in that class, ` although it ought to be included in the same class with a deeper well, when the latter is situated on the plateau. I have, however, found that such a correction would not materially alter the results, and that for all practical purposes the classification, as suggested in my former papers, is quite sufficient. The classes were— | I Class, all wells below 151 feet in depth. II » wells from 151 to 200 feet in depth. IH » » » 20110250 » » IV » دو » » 300 2510 » وو‎ V n „ morethan 300 у » » According to this classification the following numbers of produc- tive wells were registered in :—- A Class. Depth. 1888. 1891. | 1893. 1895. I , Below 151 feet 5 » . ° 33 59 36 86 П .| From 151 to 200 feet. А ° | 67 97 86 127 HI „| From 201 to 250 feet. . š : 143 187 187 192 A IV ‚| From 251 to 300 feet, қ . he 35 33 07 105 V .|Моге than 300 feet „ | ВЕ 3 | 1 etn 9 TOTAL . 281 | 577 | 406 519 AA — 0 22 ———— Three features are very striking ; the large increase of the shal- . lower wells, namely, such of 200 feet and under since 1888, and the equally large, if not larger increase of the deeper wells and the re- markable constancy of the medium depth wells. | In 1888 the shallower wells (I and II Class) aggregated 100, a figure which increased considerably in 189r, but fell off againin 1893 when no more fresh wells were sunk, and the existing ones gradually deepened. In January 1895 the shallow wells reached the unpre- | ( 229 ) 184 NOETLING : PETROLEUM IN BURMA. cedented number of 213, that is to say, an increase.of over 100 per cent., as compared with 1888. The reason of this enormous increase is easily explained ; after 1893 the new part of the Twingon reserves, namely, its south-western corner which hitherto contained only a few wells, was rapidly exploited, because some rich wells were found in this part, which drew their oil from the 1st oil sand. Nearly all x the new wells, to the number of 107, which have been constructed | between the end of 1893 and January 1895, are situated in this - part, and as the 1st and 2nd oil sand have not shown signs of exhaus- tion, they stillbelong to the shallow wells, If we deduct the number of these newly constructed wells, from the total, we obtain 106, that is to say, a figure which very nearly corresponds with the number of the shallow wells in 1893, viz., 126. We may therefore suppose that the number of shallow wells in the older part of the oilfield has re- mained almost the same, showing a small decrease which will pre- sently be explained. In other words we may deduce from the above figures the fact, that no fresh wells have been constructed in the older parts of the oilfields, which obtained their supply of oil from the first or second oil sand. The next very striking feature is the enormous increase of the deeper wells since 1888, in that year 38 were recorded alto- gether, in January 1895 there were 114, or an increase of 200 per cent, This also can be easily explained, a pit well is generally deepened when it begins to fall off in production; there was no particular need of increasing the depth previous to 1891 when the same quantity could be attained by increasing the number of wells. | When no fresh wells were allowed to be constructed, the falling off of the production of the individual wells immediately necessitated steps to be taken to secure their former production. The steps naturally resulted in an increased depth, and we see towards the beginning of 1893 the number of the deeper wells almost trebled since that year, when the construction of fresh wells not only kept ( 230 ) | | RUM DEPTH OF WELLS, - EE up, but considerably increased the production, the necessity of deepening the older wells was less pressing, and we see, that since 1893 their number has only been increased by 17. The steadiness of the number of middle class wells, vzz., those between 200 and 250 feet, on which as we shall presently see, the production chiefly depends, is remarkable. The only increase is recorded between 1888 and 1891, when 44 were added to their number, These wells, which derive their supply from the 3rd oil sand remain therefore for a longer time productive without the necessity of being increased in depth, and whatever number is taken off by the wells becoming deeper is added by the same number of shallow wells advancing to the middle class stage. In discussing the shallow wells I stated that they showed a small decrease of 20 in 1895 as compared with 1893; now if we add this number to the total of the III and IV class wells, we ` obtain the number of 304 or nearly exactly the same figure to which the sum of the III, IV and V class wells amounts in 1895, vzz., y 306, or, in Other words, the depth of the wells has been only slightly P increased since 1893, no necessity having arisen for doing so. 2. Production of the pit wells.—In my two previous papers I | classified the productive wells into six classes according to the | quantity of petroleum each well yielded per day. This same clas- sification will be again followed as it has been proved the most convenient form to examine the pit-wells from this point of view. The wells are, therefore, divided into— | Ist class wells yielding less than 21 viss per day, ` ) | | ME ot ne ОИЕ kaso... э, 14 за y з 5 »2:5:f0/100 ss Cath: os. š e ; А 5 . -IOI to 150 sth . A к SUN ME . 151 to 300 oth. , o i tee -more than 300 ( 23: ) 186 NOETLING: PETROLEUM IN BURMA. The following table will show the number of each class of wells _ аз recorded in the years stated :— е Class, Daily Production, 1888. nr 3895. 1895. 1 | Wells yielding less than 20 viss . r 128 166 142 192 2 A „ from21 to 5oviss . ° 54 94 110 140 3 A 5 » БІ to roo viss , . 52 | 76 85 103 j 4 Ж » » 101 to 150 viss . ° 27 24 33 54 5 » » »IS51to200vis . - 17 17 31 28 б Ж , more than 300 viss . . 3 ee. 5 2 TOTAL A 281 377 406 519 (a) Wells of the rst class.—From the above figures it will be seen that in every year in which the observations were taken those wells which yielded 20 viss and less per diem are far in the majority. The percentage of the total number was in ЖТТ AA 1891 . 4 - - ° ° қ $ : и AL 1893 . : А - 5 ; . - SEC e 1895 . ° ° . - ° ° ° . . . eee It cannot be considered as a very promising sign that the poor wells form such a large part of the total number, which amounted to nearly one half in 1888 and has never been less than one-third. The percentage seems to be steadily on the decrease up to 1893, but since then an increase has again been noted. (6) Wells of the and and 3rd class—A steady increase is re- corded in wells of the 2nd class, inasmuch as they have increased in number from 54 in 1888 to 140 in 1895; it will, however, also be noted that the chief increase took place from 1888 to 1893 when their number more than doubled. The same applies to the wells of the 3rd class showing also an increase of nearly 100°/, in 189 ( 232 ) қ YIELD OF WELLS, ` 187 against 1888, The percentage of the middle class wells was as fol- lows, in | 1888 . . š ° . ` Ірге MER Е S i i РЧ I 891 ° ° “ . . ° ° ° ° ° ° 45 lo 1893 Ы .. . = ° . ° . . . ә 48°], 1 89 Ee * š 4 ° ° ә ° ° ° . 467 o Although we notice a certain increase since 1888, the percentage has kept very steadily a little below one-half of the total for the last four years. If we consider the wells of the first three classes together we notice that notonly do they form the vast majority of the productive wells, but that their percentage keeps remarkably steady, being 82°/,, 89 °/_, 82°/., 83?/,, in the years referred to. If we were to judge the prospects of the oilfield from these wells it could not be asserted that they ` were very promising ones, when the overwhelming чау о of the wells yields less than a barrel a day. Wells of the gtk, sth and 6th class.—There is also an increase in number since 1888, particularly noticeable in the wells of the 4th class, which have exactly doubled, but on the whole their percentage has not much changed, being in no case more than 18 ?/,. . We may therefore conclude that roughly 2 out of every 5 wells, constructed according to the Burmese method, will yield less than 20 viss per day, 2 between 20 and 100 viss and only 1 more than roo viss. It therefore fully bears out the conclusions I arrived _ at with regard to the production of the pit wells in my first paper. In my former papers I found it useful to give in а separate table the total daily production of each class of wells. I think, however, that such a table is superfluous, as it conveys no other ideas beyond those already deduced from the number of the wells in each class, Each class being established on the base of a certain fixed position, it is clear that the aggregate production chiefly depends on the num- ber of wells contained in each class, and if we were to multiply those with the average for each class, we should arrive ata fairly correct idea ‚as to the daily production of each class, ( 233 ) 188 > ` NOETLING: PETROLEUM IN BURMA. Much more important is the relation between depth and produce | tion, that is to say to investigate the aggregate daily production of the wells belonging to the same class of depth. Such an examination will convey a very good idea as to which of the oil bearing sands chiefly contributes towards the supply of petroleum. The following table will show the aggregate daily production of each of the five classes of wells as they were arranged on page 183 :— Class, Depth, 1888, 1891, 1893. 1895. I | Less than 150 feet . . ° ° 984 1,384 1,132 2,795 H | From 151 to 200 feet . i А ‚| 2511 3,407 3,003 6,272 ; HI | From 201 to 250 feet . ° ° .| 9,255 | 10,497 | 13,203 | 11,825 IV | From 251 to 300 feet | . . ‚| 2,754 2,557 9,110 8,064 V | Моге than Зоо feet . ° А " 365 70 T 745 ToTAL .) 15,869 | 17,915 | 26,538 | 29,701 Two features are the most striking in the above table, the preponderance of the production of the III class wells and the marked increase in the production of the shallower wells in 1895, while that of the deeper ones shows a slight, though noticeable, decrease, As before it will be useful to consider the different classes by them- selves. | (a) Zand II class wells.—In 1888 the aggregate production of these wells amounted to 3,495 viss or 23°/, of the total, there was a slight rise in 1891, and a distinct decrease in 1893, while in 1895 the production rose to 9,067 viss equal to 35°/, of the total production, that is to say, within about 13 years the production had тоге. than doubled, and almost trebled as compared with 1888. As explained this is chiefly due to the exploitation of the south- «western corner of the Twingon oilfield, which had hitherto been scarcely worked, and where the 1st and 2nd sand still contained a good quantity of oil. If it had not been for this the production would most (225453 Era e e а а 3 YIELD OF WELLS. . 189 | probably have Жы; as will be seen by the examination of the other figures, because notwithstanding the enornious rise of over 1009/, in the production of this class of wells the increase of the total production has only been 3,163 viss or about 18 °/,. If we assume that the wells of the first two classes in the older part of the field yielded the same quantity in 1895 as in 1893, we find that the increase in this class is 4,842 viss, which represents very nearly the output of the 107 new wells. | (6) 11 class wells.—The wells of this class chiefly drain the 4rd oil sand, and since regular observations were made, they have proved to be the chief supporters of the petroleum production. Their shares were, in 1888 ° ° ° ° • ° ° ° j ° 58'3 o 1891 . . ° ° . - . s 58757 1893 . ° ә ° ° ° ° ө [] 497 vis 1895 . . . $c rs SIS fs We see therefore that, notwithstanding the preponderance of the ІП class wells as regards the absolute number, their share in the рго- duction has been slowly but steadily on the decrease since 1888, and the balance has shifted more in favour of the other wells. In 1893 _ the deeper wells had to supply the deficit, in 1895 the difference was nearly equally divided by the shallower and deeper wells. Now if we keep in mind that with the exception of a few, the III class wells are situated in the older part of the oil fields, this is by no means a favourable indication for the future. In fact we may assume that within the area of the native reserve the 3rd oil sand begins to show sigus of exhaustion, and the wells draining it begin to fall off in | production. (e) JV and V class wells.—Much remains to be said stank these wells : in former years up to 1891 their contribution towards the total production was small, being 19:6 °/, in 1888 and 14 °/, in 1891 ; after 1801, for reasons already explained, their share suddenly rose to the extent of 34'3 Yo but since that time it has again slightly fallen off to 29°7°/, chiefly on account of the recently constructed shallow wells - which fully supplied the production without the necessity of deepen- | ( 235 ) 190 NOETLING : PETROLEUM IN BURMA. ing the wells. We may, however, expect a rise after the production of the shallow wells has declined, a possibility which, in my opinion, - is to happen very shortly if the exploitation of the 1st and 2nd oil | | sand in the smallarea of the south western corner of the Twingon reserve goes on at the same rate as it has been doing during the last year. | | More instructive even than the aggregate production of each class of wells is the investigation of the average production of the indivi- dual well in each class, as shown in the following table, The average production of a well in each class amounted to in Burmese viss: — Crass, 1888, 1891. 1893. 1895. I А . ° А ERIS ° 266 |. 255 | 314 325 М d “ & e Ц š 272 351 36'0 493 ЖИЛ STT uy CLIE UMEN 647 561 706 6r5 IV A - š A š : Š 897 "pr 940 | 768 мі; жолы ту . ші d 120'6 70 ase 827 GENERAL AvERAGE 4 56:6 475- 656 572 Тһе most striking feature of this table is the remarkable change in the general average, from 1888 to 1891 there was a distinct decline which was followed by a rapid rise in 1893, the average for 1893 is in fact the largest average yield ever noted, and it is certainly no mere coincidence that such a high average was obtained, at the same time when impossibility of digging fresh wells had led to the deepening of the existing wells, and by this increase of depth new parts of the oil sand were opened which yielded a good supply of petroleum, Since 1893 a distinct falling off has again set in amounting to 8'4 viss per well. This seems small enough, but let us ( 236 ) YIELD OF WELLS. 201014 realise how much it actually means; there are 519 productive wells, which if the average for 1893 were kept up would produce 1,21,788 viss per mensem more, or instead of an average turn out of 7°9 lakhs of viss there would be a production of о lakhs of viss. The decline in the average yield of 1895 can certainly be attributed to a decline in the yield of the deeper wells which is by no means balanced by a corresponding rise in the yield of the shallow wells. In fact it may almost be considered as certain that if that rise had not happened and if the shallow wells had retained the average production recorded during the years 1888, 1891 and 1893, viZ., 349, 30'7 and 34'6 respectively, instead of rising to the average of 42'5 viss, the present rise in the production would not have happened at all, but instead of it, we should probably have seen a decrease in the production. That such a rise in the average production of the shallow wells has taken place, is as already pointed out solely due to the exploitation of the ist and 2nd oil sand in a part of the Twingon Reserve by means of a number of recently constructed wells. | (B) Unproductive wells. (1) Abandoned wells.—The remarkable feature in connection with “the unproductive wells is the apparent constancy in the number of abandoned wells, which as will be seen from the table‘on page 180 has undergone very slight changes only. This may be explained thus: during the years 1891 to 1893 some of the better preserved abandoned wells were repaired and deepened, thus changing them ` into productive wells while others which could no longer be kept up fellin disuse. This fact has been recorded in several instances, but it would be useless to mention each case in detail, but for reasons already explained, I fear that there will be a considerable increase in the ber of ui wells, within the next few years, | | | The proportion оа productive and ies wells may be ( 237 ) 192 ` NOETLING: PETROLEUM IN BURMA. roughly expressed in the following manner; for every two abandoned wells there were :— | | 2 productive ones in 1888. 3 ” 3 in 1891. 4 » » in 1893. 5 » ” іп 1805. More accurately expressed the figures stand as follows :— 53: 47 in 1888. 61: 39 in 189r. 63: 37 in 1893. 65: 35 in 1895. It is therefore evident that the proportion is a fairly constant one which has during the last years slightly changed in favour of the Ў productive wells. Тһе proportion is of some importance, as it offers means for estimating the number of wells during the former years and thus checking the statements regarding the number of the wells in the Yenangyoung oilfield made by former visitors (see above, page 178). | 2. Wells under construction.—In former years when the demand for petroleum was not so large, the number of wells under construc- tion was apparently a small one, and probably new ones were only constructed when the old ones had fallen in disuse. Unfortunately the figures for 1891 and 1893 cannot be considered as proof because, as I have already pointed out, the construction of fresh wells was stopped during those years, and only those which were already in progress were permitted to go on. It is, however, reasonable to sup- pose that it never attained anything like the number at the beginning of 1895, víz., 151 ; if the progress had been going on at anything like this rate during former years the abandoned wells ought to exist in thousands instead of in hundreds. We may therefore safely sup- pose that the present enormous number of wells. under construction ` is something unusual, and that the next years will see a decided decrease. | 3. Well sites, — The existence of the well sites is solely due to the recent settlement of the native reserves, which has made (һе well ( 238 ) UNPRODUCTIVE WELLS. 22-193 : site a marketable commodity. Informer times there was no such competition for securing the best places as now exists; when a man desired to dig a well there was ample, room for it, and he had not to secure a place for a well years before he was in a position to begin to dig it. Now a well site is worth about R50 and readily sold for this price to any applicant by the twinzayos. But as not every buyer is in the position to pay at once the expense of constructing several wells, he secures perhaps a dozen well sites, while he actually constructs only one well. Of course the number of well sites within the reserves is limited, as it depends on the area of the reserves; it was found convenient to allot two square chains to every well site, and the area of both the Twingon and Beme reserves contains 450 acres, hence the theoretically possible number of wells amounts to 2,250; of these 1,190 are already in existence, thus allowing space for 1,060 more well sites ; in ether words, more than half the allotted area has been disposed of. Owing to the physical con- | stitution of the ground it will, however, be extremely difficult, if not impossible, to divide the remaining area in such a way that 1,060 additional wells could be conveniently located, in fact it is more probable that the actual number will be far below that figure; however, if the remaining land were to be sold at the present rate of, say, 200 well sites a year, it would be disposed of in less than five years. | We may now sum up our review of the changes the pit wells have undergone during the last seven years in a few words. There has been a great increase in the number of productive wells, their depth, and their production since 1888. Although this seems to indicate a very prosperous state of the native oil fields such view is a deceptive one, because the increase of production has solely been the result of the construction of a number of fresh wells in a hitherto hardly exploited part of the reserves, while, on the other hand, those wells situated in th e older parts of the field, which formerly chiefly supplied the production, show a distinct decline in yield notwithstanding their increased depth. | 0 | ( 239 ) 104 NOETLING: PETROLEUM IN BURMA. SECTION IV.—THE PRODUCTION OF THE PIT WELLS. A.—Period previous to 1886. The question of the quantity of petroleum produced by the Bur- mese oil fields has of course at tracted the attention of the visitors ` since the earliest times. There is hardly any account in which the authority does not attempt to estimate the production by a more or less sagacious method. The general mode adopted is to multiply the number of productive wells by the average yield per well. Fair results could certainly be obtained in this manner if the actual ` average yield per well was known with accuracy ; any erroneous statement must natural be of great influence as regards the esti- mated production. Now as far as my experience goes, it is ex- tremely difficult to obtain an accurate estimate of the average yield per well by relying only on native information; the data thus re- ceived vary so much that their value is more than problematical. The following table will show the figures stated to express the average yield per well since Captain Cox's time :— Table showing the estimated daily average yield per well. Average Year. Name. daily yield in viss. 1707 ° ° ° Captain Cox " ° . e vo. . 3o0 1890, ls . | Mr. Crawfurd : > : UE. E Ek 235 1838. . - . | Captain McLeod . Е - А ^ X ls 56 1855 ¿e - ‚ | Dr. Oldham А : . . ° р 180 1855 > . | Dr. Oldham, different estimate 7 ьо . ee Теш ° e . . 220 1855 + ° . | Captain Yule ) 4 Beme . SE RIT NT E 5 40 1873 + Š . Captain Strover . ° “wik. ° . 100 1879-81 А `. | Burmese Minister , KE ae Жы e ° 50 PRODUCTION OF PIT WELLS, ER The figures in this table differ so widely that it is not difficult to see that some must be erroneous. Unfortunately there are no means of checking them, all what I can do isto express my personal opinion, I believe that Captain Cox and Mr. Crawfurd’s estimates are too ` high, while it is quite certain that Captain McLeod's estimate is much too low. As regards the estimates of the members of the Mission to Ava, I believe that Dr. Oldham's first estimáte is too high, while his second is probably a little too low. It is further beyond any doubt that the average of 200 viss per well in Twingon, as esti- mated by Captain Yule, is too high, while his estimate for Beme is equally too low. Captain Strover’s estimate seems fairly correct, while that of the Burmese Minister seems apparently too low. It seems perfectly clear that estimates regarding the monthly pro- - duction will still more widely differ, not only on account of the estimat- ed average production per well, but chiefly because the number of productive wells greatly varies according to the different observers, as already pointed out on page 175. Now the following table will show the monthly production of the Yenangyoung oil field, as estimated at different times :-- Table showing the monthly production of the Yenangyoung oil field during the period 1795 to 1896. Year. Reference, Monthly production in viss (2) lbs. 3°65. 1795 . Colonel Symes . 5 Е : A . 4,635,900 1797 . Captain Cox - š қ ° . . 4,745,000 1826 . Mr. Crawfurd - . 4 e š . 1,464,000 1835 . Captain Hannay . . А . . . 4,743,000 1838 . Captain McLeod . ° - : . >, 117,120 E" 1855 . Dr. Oldham : ° ° - e а 600,000 1855 j Do. different estimate ` . 4 > $75,000 1855 . Captain Yule A А ° - - e 596,000 1873 . Captain Strover . - . : . . 500,000 1879—81. Burmese Minister А - 4 A . 400,000 1886 . Пт, Romanis > 2 a . ° e 600,000 1886 . Sir Charles Bernard | : : 4 ə 500,000 If we assume all these figures to be correct, the production must have largely fallen off since the end of the last century, but we will at 02 | ( 245 ) 196 NOETLING : PETROLEUM IN BURMA. once see that the large output of 4'7 millions of viss per mensem, is based on erroneous suppositions, On page 178 I pointed out that the number of wells at the end of the last century was pro- bably not more than 130, of which 7o were productive wells. Suppos- ing there were 100 and Captain Cox's estimate of 300 viss per day to be correct, the approximate monthly output would not be more than 9 lakhs of viss. But I think that even this reduced estimate is much too high, as I doubt whether there was such a large consumption of crude oil in the last century as to absorb a monthly output of 9 lakhs of viss, considering that during the last five years the local consumption (including India and Shan States) of crude oil amounted to not more than 1 lakh of viss. If we assume that before the influx of American oil the local consumption amounted to 3 or 4 lakhs of viss per mensem it is not easy to see what could have become of the surplus of 5 to 6 lakhs of viss. But even supposing the estimate of 9 lakhs per month to be correct, we can at once dispose of the state- ments of Mr. Crawfurd and Captain Hannay as being too high, and that of Captain McLeod as being undoubtedly too low. We now come to the estimates of the members oí Yule's Mission to Ava. They furnish three estimates ranging from 3? lakhs of viss up to 9 lakhs of viss per mensem. It remains to examine which of the three statements is to be considered as the most reliable, Dr. Oldham arrives at the lower estimate judging from the number of carts engaged in the oil trade, and by supposing the average load of each cart to be 100 viss. I will not argue about the number of cart- loads, supposed to be 150 per day, but the estimate of 100 viss per cart- load is undoubtedly much below the mark. Each cart now carries 12 pots, containing at least 12 viss of oil, that is to say,12 x 12— 144, say 150 viss. We know, that in the oil fields nearly everything has remained in the same condition as it was a hundred years ago, and it is quite fair to suppose that the quantity of oil carried by one cart is the same now as it was in 1855. Dr. Oldham's second estimate (C 242 1) PRODUCTION OF PIT WELLS I97 must therefore be raised by half of its amount, if it is to come near the truth, and this will give an annual production of 57'5 lakhs of viss or 562,500 viss per mensem. It is then beyond doubt that Dr. "Oldham's second estimate is too low. . On the-other hand, in his first estimate he assumes the daily aver- age production per well to be 180 viss. I dare say that this is rather too high an average, and I therefore think his final result to be too high. | Major Phayre arrives at his estimate in rather а remarkable way. . He assumes the average yield per well in the Beme oil field to be 40 viss -per day, in the Twingon area to be 230 viss. From all I know the estimate for Beme is undoubtedly too low, that of Twingon too high, but the two mistakes have apparently compensated each other and so Major Phayre's estimate of 5'96 lakhs of viss per month is very near the mark as it agrees well with the amount arrived at by correct- ing Dr. Oldham's second estimate. If we therefore suppose that the monthly output in 1855 amounted to about 6 lakhs of viss, we shall certainly rather be above than below the mark, | Not much can be said about other estimates. Captain Strover very likely gives the actual output during the year referred to. During the following years the production must have fallen off because, as we shall presently see by estimates arrived at by a different method, the statement of the Burmese Minister as to the output of 4 lakhs of viss which dwindled down to about 33 lakhs of viss is corroborated. B.—Period 1886 to the end of 1894. _ Since the annexation of Upper Burma, careful records have been kept of the monthly production; of course they were interrupted in 1886 when owing to the disturbed state of the country, all work at the oil fields was stopped, and we find therefore that for this year the amount of production is only returned for seven months, Another pause happened in April 1887, but ever since the work has been ( 243.) 198 NOETLING : PETROLEUM IN BURMA. steadily going on, as will be shown by the figures of the following table :— Table showing the monthly. production of the Fenangyoung native reserves from 1886 to 1894 in viss at 3°65 105. 1887. 1888, ر ا س 1893. | 1894. 1889. 1890. 1891, 1892. um ——— |—— J əəə——ə January „у, ee 588,520 | 489,380 | 503,240 | 557,430 | 403,150 | 521,755 | 697,210 | 755,300 February <+ + e 516,470 | 416,150 | 518,570 | 501,800 | 454,570 | 395,880 693,585 665,050 March "aere өө 369,820 | 488,550 | 537,770 | 569,180 | 571,100 | 352,520 | 838,530 | 804,283 April . . + | 407,060 ee 520,700 | §28,870 | 550,270 | 77,090 | 234,215 | 769,970 735,100 May . : 532,120 | 601,390 | 539,750 | 540,900 | 533,260 | 608,600 | 505,630 | 629,510 | 836,700 june . 4 . | 462,510 | 586,260 | 530,290 | 551,040 | 608,130 928,290 551,640 | 766,500 | 801,350 July .. E . | 370,520 | 522,050 | 534,170 | 525,130 | 661,210 | 712,330 | 723,050 | 816,490 | 822,800 August А „ | 657,090 | 494,650 | 535,070 | 542,960 | 579,450 | 572,635 | 811,315 | 802,750 | 811,180 September , . | 422,660 | 494,720 | 523,730 | 532,210 | 627,960 570,650 816,405 | 724,920 | 790,540 October : : a 502,910 | 516,000 | 548,770 | 608,500 | 631,200 | 725,185 | 634,940 | 813,360 November . E od 503,740 | 519,260 | 539,500 | 567,500 638,960 725, 695 793,000 | 778,120 December . „ | 506,130 | 470,670 | 512,360 | 539,690 | 387,740 | 635,221 | 718,750 | 750,490 | 844,880 ب ا تاا | LL———————— т‏ | || TOTAL • |3,418,090 |5,651,200 [6,125,410 | 6,408,650| 6,761,430} 6,803,796| 7,082,040|8,017,805|9,459,563 — | — Average per month | 488,415 | 513,745 —— ff — — |— . %— |——- اا‎ 510,450 | 534,054 | 563,452 | 566,983 | 590,170 | 743,158 | 788,297 Although this table explains itself a few words may be said regard- ing the extraordinary low production in April 1891. This is solely due to the disorganisation of the oil trade which immediately followed the termination of the agreement made in March 1886 between the native well owners and the Burma Oil Company; the natives refused to sell their produce expecting to obtain a higher price for it, but as by that time the Burma Oil Company was independent of the supply from the native wells, the opposition soon broke down as the well owners found no buyers for their oil, and in the following month work was resumed in the ordinary way. We may observe from the figures in this table that the average ( 244 ) \ Ta / THE DRILLED WELLS. 199 monthly output has been steadily increasing since 1886 ; it amounted Ine i 1886 to е а ° . . 488 lakhs of viss. 1887 ,, . А - ° T 5'13 m. M | 1888 ,, " ° ° . e 5'10 A Y wl 1889 ,, ат, „МЫЗ ч PREND 1890 و > 5:63 ° . ^ . : وو‎ » 1891 » ° . . . ” 5:66 » » » 1892 T А ` a . y 5'90 ” о” 1803 1) . ° . . . 743 » » р 1894 " . . ° ° ° 7:88 » » The increase was very slow up to the end of 1892, but during the following year a sudden rise took place, increasing the production by 14 lakhs of viss. As we know that in that year the number of productive wells had not much increased we must attribute this rise chiefly to the deepening of the wells which were thus rendered more profitable. A small rise, amounting to a little less than 1 lakh of viss, was noticed in 1894, but this can be attributed with great certainty to the new wells dug between 1893 and 1894. SECTION V.—THE DRILLED WELLS. Although boring for oil in Upper Burma was started.as early as 1887, it cannot be said that during the following year the progress of operations had been either rapid or extensive. Kodoung, between the Twingon and Beme area, had been selected for the operations, and up to end of 1888 only two borings were made, one of which hardly yielded any oil. Matters seemed very little encouraging, but the Burma Oil Company, which had undertaken the borings held on, and eventually success awarded their exertions, The year 1889 marks an epoch in the history of the Yenan- gyoung oil field, because it is in this year that the number of borings at Kodoung quickly increased. In the following year the Burma oil syndicate started boring operations south of the Beme tract, in blocks 1 S.and 2 S., they were, however, not awarded the success they deserved, none of the holes produced even a trace of petroleum, although considerabie quantities ( 245 ) 200 NOETLING: PETROLEUM IN BURMA. . of gas emanated from the borings situated close to the Beme tract. The syndicate eventually gave up the operations, tools and plant were sold, and this chapter in the history of the Yenangyoung oil field may be considered as closed. The Burma Oil Company had in the meantime not been idle, and the land north of the T wingon area was tested where some oil was found in blocks 1 and 2 N. | p I may here mention that two systems of drilling were used in the construction of bore holes. The Burma Oil Company first used the rod, but eventually changed for rope drilling, The bores of the Burma oil syndicate were throughout drilled with the rod. Without going further into the details of the two systems, it may be interesting to say a few words as to which system apparently proved more ad- vantageous in the Yenangyoung oil field. There is no doubt that the cable system has the great advantage of quickness, which is tke more apparent the deeper the boreis. On the other hand the rod system has the advantage of rigidity and weight, which enables it to force its way when the cable fails to do so. It seems that when strata like the clay (e p. 94) which caves very badly, have to be repeatedly drilled through, the cable system works quicker and is therefore more economical up to a depth of about 4oo feet from the surface. ` Deeper holes have only been drilled under the greatest difficulties with the cable, while the rod by sheer weight forced its way in a comparatively short time through the caving masses found between 800 and 1,100 feet, However the case may be, the ducis of the personal equation must not be entirely disregarded and a workman accustomed to drill with the rope, might fail with the rod, because he looks at the latter as a very inferior system, Mutatis mutandis the same holds good for a driller who only knows the rod drilling system. « Without deciding the question which system would be the most economical for Burma, I may offer one caution, which will apply to either case, and this is, that the first rig intended for test boring only should be as light as possible, Access to those localities ( 246 ) ee wea (X. 7“ ES drm +, В. y w ч ” ٤ ғ, б Е " ý . í THE DRILLED WELLS, 201 which will have to be tested in future, is extremely difficult, if not altogether impossible, for heavy machinery. There are no roads worth speaking of, except such as may be passed by mules, and even such parts as are comparatively close to the river, like the northern continuation of the Yenangyoung anticline, are so abso- lutely destitute of water that the question of water supply for the boiler would involve either enormous expense, or would: „Cripple the experiment before it has actually been started. ` Number and depth of drilled wells — Although the. first drilled well was not commenced earlier than 1887, there is already, some difficulty in ascertaining the total number of wells drilled. Some of them were dry holes, therefore,abandoned, and no further traces can be discovered of their location ; there are at least five of these wells, to which has been recently added a sixth one, the location of which however is known and the boring record is preserved. Of the others the location and boring record of the pioneer well, so to speak, is known to me, although it is entirely abandoned now; I gave this well the distinguishing letter A ; two more wells were drilled, if I am not mistaken in 1888, both of which have been aban- doned ; another couple of dry holes were drilled in 1880, their location is unknown, as well as the record of the strata met with ; another well was drilled inside one of the pit wells (Government well No. 131) ; it hardly yielded any oil and the piping was with- drawn and boring register unknown. Well No. 64 yielded no oil, luckily its position and boring register, which is extremely valuable from a geological point of view, have been preserved ; but the rig has been removed and another No. 64 has been just finished west of well No, 21 ; I numbered it No. 64A, The Minlindoung wells drilled by the Burma oil syndicate, 1890 to 1892, in blocks S. 1 and S. 2 south of Beme have been abandoned, and their traces will be entirely obliterated after another rainy season. There are therefore at least 14 drilled wells which have entirely disappeared, and if of the majority the boring record and location is known, some of them have left no traces behind. As there ( 247 ) 202 NOETLING: PETROLEUM IN BURMA. аге at present (February 1895) 67 wells in working order, the total number of drilled wells cannot therefore have been less than 80. These 80 wells are distributed over the area of the Yenangyoung oil field in the following manner :— 7o were drilled at the central part of the field, Kodoung. 2 (No. 44 and 45) were drilled in blocks N. 1 and N. 2, north of the Twingon reserve. 1 (No. 68) was drilled west of the Twingon reserve, 7 (Nos. I to VII) were drilled in block S. 1 and S. 2, and south ofthe Beme reserve. The greatest depth reached was 1,011 feet from the surface ; this bore has, however, been abandoned as it yielded no oil. But by far the majority of wells have only reached a depth of between 400 and 400 feet from the surface; they are therefore comparatively shallow wells. | 2. Production of the drilled wells.—As this is the most import- ant feature, I tried to secure as much reliable information as possible in this matter, but unfortunately those things which are of import- ance to the scientific observer are not always of the same interest to the practical man. His sole aim isa high production, and to get this as quick as possible his chief interest ; but still features in the production have been ascertained which are worth mentioning. The highest daily production of one well hitherto observed, was 13,000 viss or nearly 130 barrels of 42 gallons. This may be a large yield for Burma, but it is insignificant with that observed at the wells of Baku or the United States. It has also been observed that the yield of a freshly drilled well is very considerable during the first few days, it then generally falls rapidly off for a short time and eventually settles down to a certain quantity, which it keeps for years. The remarkable feature is that some wells, although they have steadily produced oil for at least six years, have shown no signs of exhaustion yet. The following table will show the monthly production of the drilled wells in the Yenangyoung oil field :— B. ( 248 ) 203 PRODUCTION OF DRILLED WELLS. =. hm 9: с1С'бор1 | 6/2004%1 | obs'£16'z1 | ooS'oLg'9 | ogo'iZo'& | o£1'Lzb об$\тў 1у101, rn | E 662%1/4 6zg'gzS ofS #26 oof ‘6SS 08389 o1Z'£€1 n s : ы 1ә94шә2әа Se E glS‘o6L't egt аға оё1'©©/ өзе ог2 486 o69'cV1 006% : : B 19QUISAON | eV £'c£of1 LgL'£96 ozz'go£'1 ooS'gıg ogr'glb. 090'93 090'S E š ç ° 24000 ` Я vS6'9ogi't | t£o'b££'1 | 0564914 005 Log | овоше o6b'oz Fe eon б^ deudas 1bo'L£S'1 -06b'S18'1 о42:652 062'298 ogS'6oS 060'98 bes k ; 5 ° 3sn3ny | 1 (тібейа | 19€'1 181 oz6'99£'1 | 019/806 og ‘og 0Lg'9 .. XT cett RU saa | TAS 8166%0 9616'1 o££'9£9'1 og£'SS9 олі ооо‘ - 028€ x ч : ° Өш | TES, EY 120628 69g'E1S'1 005 'zEL'1 o££'60L o098'LSz 060'1Z 098% : 1 ۳ е Керү ` 2 Es | 3 Б -6rg'Soo'I Sz6'gob'1 006'1to'1 065'69S 002262 01961 025% E i dy «M £ 2660111 0080204 оо 460 010'8 o£€'ozz 00S'S 0006 s x , та PEN 6 9So'r66. ogz'ezg 006'829 оба ос o£9'101 oog'S 0Z9'9 ° $ > ee З p Ë ‘ele'6z0'1 obL‘ggS 000'988 059°0L oL1'g11 oor — ogS'I O ЕЕ S I T “7681 "£691 72681 ‘1691 '0581 '6881 78881 А, ae E : 204 NOETLING: PETROLEUM IN BURMA, The chief interest of the above statement rests in the, comparative- | ly speaking, large increase of the production within a few years. During the year 1888, the insignificant quantity of 415 barrels only was produced ; in the same year the pit wells yielded 61,254 barrels, that is to say, over 147 times the quantity ; it cannot be said tbat this was a very encouraging start, after the large expectations, although it must not be forgotten, that there were only two, at most three, drilled wells in 1888, but unfortunately these were constructed in the poorer region of the field. However, undaunted by this disappointment, the company went on, and the production at first rose slowly, but with the increased number of wells, quicker, till in 1891 with 68,705 barrels, it has not only reacked the production of the pit wells, but eu it by a trifle, the latter being 68,037 barrels. From that time the drilled wells had the upper hand, because from 1891 to 1892 the production rose from 68,705 to 129,135 barrels, that is to say, an increase of about 88 per cent. The next two years show again only a slight increase, 1894 closing with a production of, 154,695 barrels, that is to say, exactly 14 times the production of the pit wells which amounted to 94,595 barrels during the same year. It is certainly by no means a bad progress that within seven years the production of the drilled wells has increased to such an extent, that from being „iz of the production of the pit wells at the end of the first year, it amounts to 13 times that production at the end of the seventh year, although this same production has more than doubled during the same period. If anything can prove the superiority of the drilled wells over the dug pit wells, these figures should do so. It may perhaps be argued that the drilled wells have been constructed in a richer region of the ` oil tract, but so far as my experience goes, this is by no means the case, if anything, the Twingon area is decidedly the richer portion of the two, the 1st and 2nd sand being petroliferous, while they are is at Kodoung ( 250 ) YENANGYAT OIL FIELD. 205 E d | SECTION 6. SUMMARY OF THE PRODUCTION OF THE К E Pt E YENANGYOUNG OIL FIELD. -— bt. 4% . In the ойо table is given the production of me Yenangyoung ) oil feld for the last n nine years :— E be | | ` Production in viss. e ) 1886 y TM E MM t - 3,418,000 868777. 4 . °. . . 5,651,200 1888 » ° - d ° E 6,167,000 КТА A ДЫ SER 6396985 09 ·- 1890 I nie); +o . e >e 10,432,510 м 1891 è Š ES aa Me. + 13,674,296 қ I 892 . = s . жаттан. I 9,995,58o E 1893 . . . ° . . 23,624,174 түу 9. б 1894 . z + DN А N E within nine years the production has risen from 34,180 barrels 240 290 barrels, that is to say, an increase of nearly 800 per cent. similar increase were to be expected during the next nine years tters would look more promising, but as I have pointed out pre- usly (page 123) it is more than doubtful whether a similar rise may expected, A comparison of the production of Upper Burma ` with that of other countries will be paipoar till the Yenangyat { E o; il field has been discussed. ew ; d E ONE r 4” М CHAPTER 11.—THE YENANGYAT OILFIELD. SECTION L--THE PIT WELLS. A.—Period previous to 1667. As already mentioned (see page 124) the surface indications of the istence of an oil bearing sand near the hamlet of Yenangyat were 22 noticed by previous visitors, as Mr. Crawfurd апа Dr. Oldham, but E itis almost certain that no exploitation of this part took place until a E very recent period ; there were certainly no wells in existence when _ the members of the Mission to Ava visited Yenangyat in 1855, and the y T statement that the first wells were constructed in 1864 is highly pros 4 m _bable, AA it seems quite likely that they are even younger. ( 251 ) 2o6 NOETLING : PETROLEUM IN BURMA. According to Burmese statements these were constructed in the Burmese years : — 1216% to 1222 .. ¿ А 5 E 30 wells. 1221 to 1225 А . . . ° BO A 1226 to 1230 А + ° - 29. a 1233 ° . . € ° . ° 5 ” 1235 to 1239 . . ° 5 . ° 29. у; TOTAL (168 77,5 The first authentic information about the Yenangyat oil field has _ been given in Captain Strover's report, who states that in 1873 there were so wells at Yenangyat. Unfortunately he does not say whether this number includes the unproductive wells, or not. In the following year Dr. Friedlánder visited the Yenangyat oil field, and he gives the number of wells as 70. Dr. Friedlánder's statements are, however, very unreliable, and not much value can be attached to his figures. Ifthe data supplied by the natives are correct, then there must have been at least 139 wells in existence in 1873, the Burmese year 1233—1234 corresponding to A.D. 1873. lt is therefore probable that Captain Strover's, as well Dr. Fried- lànder's statements, refer to the productive wells only. No information has been obtained regarding the production, which to judge from our present experience can never have been large. B.— Period 1887 to 1694. My first visit to the Yenangyat oil field took place in June 1891, when a survey was arranged, and the wells carefully counted, Records of the monthly production have, however, been kept, although in a somewhat careless way, since the beginning of 1887. The wells, of which there are altogether 138, are situated in three different valleys, north of the village of Yenangyat. Among them there are — Productive wells Е ° 5 8 А 18 Unproductive wells . . . . e 120 * The Burmese year 1216 corresponds to A.D. 1864. { аса”) PIT WELLS. 207 3 К A Productive wells.— The productive wells have never attained ds a ny depth worth speaking, there are in the— | I class, below 150 feet ene gel . . 14 wells II ,, from 150 to 200 feet . . BAR, y a M which has not changed since. With regard totheir з E these belonged to the— 1 class yielding less than 21 viss . . 12 wells. LOA РА from 21 to 50 viss x x pe al daily production of 213 viss, while those of the second class Bice! only 76 viss. As it has been proved by the deep borings at all the productive wells draw their oil from one and the same oliferous sand, no importance need be attached to the above m never produced oil, a statement which I fully believe. There however no wells under construction, nor is there a struggle for v A sites observable. In fact the Yenangyat oil field gives the im- ` ( 253 ) PETROLEUM IN BURMA. . . NOETLING 208 098521 000%01 085'6 ozS'11 os¿'g 086'6 oto'ot oo1'g ob£“o1 000'6 ob£'o1 056'g Og9'o1 009'01 ogb*o1 008'01 ozg'or 009'6 OgI'II oot ‘or OZO'11 000'01 oor‘or oo£'6 Olz'1I 006'6 "Рб81 £691 oo£'£z1 OOI © I oot'6 003'11 000'6 oor‘ol oog'or oog'oIT oog'o1 oog*ot OOofOI 000'01 000'01 “2681 000'b11 006'S01 000'01 003'8 005'01 ooo'g ooZ'o01 oo£'g ooS'o1 oo£*6 ooS'11 oo£'6 000'21. 000°6 003'11 000'6 000'9 000'6 0029 ooo'6 о00%6 000'6 002'g ooZ'g 003 'g 00/'8g 1681 x *o6gt 001<01 005% 005% ооо ooS'6 . oog'g oo$ ‘6 00S ‘6 oog'6 0056 000'g 000% ooS'Z "6881 00101 00S'Z 000'L 009'Z 000'g ooS*g ooo'6 0056 ooS'6 о056 0056 00S'6 000'11 "8881 010906 008 000'9 000° 0106 ooS‘or 000'11 ooo'rt 000%91 “2881 IVLOL ° КЕР 55276 | ° a9quaAoN E 1940320 ° aəquiə)dəç . › ysnsny . . £m[ . ° eunf . . Кер ерни ° ° yore 4. Axreniqoy ° * £ienuef “#бў1 0; LOGI savak 241 4of pray 110 ¿váduvuo A 241 uz spam pd 241 Jo uorponpotg E «- br n. ч DRILLED WELLS. 79 SECTION Il.—THE DRILLED WELLS. ince the summer of 1891 a few wells have been drilled in the | gyat oil field, but it cannot be said that they have proved a cess. However, we must reserve our judgment regarding the im- rt ar nce E the Yenangyat oil field, till a few more test. wells have E the AS ravine. Of these 6 are productive ; one ot yield oil and was abandoned. The wells are generally much ере! than those of Yenangyoung, without however the object of i good ] production having been attained, ` ie Like the pit wells, the drilled wells are very poor, even much e so pe the ia I have no nd Bea ug x eon 196 de 168 gallons. If compared with the wells of the angyoung oil field, Where a well yielding 500 gallons is considered зе a poor well, the above production must appear very insigni- i vid | 1893. 1894. | 7 а x s, . E S = Ы 1 E es 54,053 r NC i Es ° . ә е е . ° . . TM Э Я 45,476 EDS ME. . . . . . . ... 44,363 za Carried over “ ps 143,892 | PA (> 255 ) 210 NOETLING : PETROLEUM IN BURMA. А МЕЛЕ, - 1893. 1894. Brought forward - wee 143,892 | April e ° . ° e ° ° . ° ke 27,229 44,099 қ May . 5 "i ° ° ° ç А š " .| 720,108 | 65,045 June . . . - ° ° ° ° > 4 «| 25,858 61,886 Jay RI AM ie boa CN August. " PY UR А NS. . ° - e | 21,350 59,500 September ` Е ° ` ° . e ° “| 25,989 59,170 October. : . А ° ° ° ° А “| 35726 60,511 November . : Е ? Е ‚ è : . ‚| 37,396 58,663 December . . ° ° > e e . . “| 51,880 63,196 TOTAL „| 281,927 674,085 This table does not call for any special remarks, except that, com- paratively speaking, the large increase of the production within one year is solely due to the increased number of wells. CHAPTER II].—THE;PETROLEUM PRODUCTION OF BURMA. Having in the previous chapters discussed the production of the two oil fields which were exploited in Burma, up to the beginning of 1895 as well as the means by which this production is obtained, there remains only to consider Burma generally as an oil producing country. I refrain from expressing my views for the period previ- ous to 1878-79, as the data available are more or less unreliable. . We are, however, able to check the statements regarding the production since 1878-79, from the returns of the import of crude oil into Burma during the financial year 1878-79 to 1885-86. There A 246.) | ; 3 * PRODUCTION. 211 being only one highway by which the oil could be transported to Burma, namely the Irawadi, the figures about the quantity of the - imported oil may be considered accurate, provided the records were properly kept. We also know that previous tothe influx of kerosine oil from America, about one third of the total production of Burmese oil was consumed in the country and are, therefore, justified in estimating with tolerable accuracy the total production from the amount of imported oil. Table showing the production of the otl-fields of Burma. FiNANCIAL YEAR, Viss. ; REMARKS, — FT. 1878-79 . .| 1,916,769 | Estimated: the year being one of political disturbance it is rather doubtful whether these figures even ap- proximately represent the actual output; it is more likely that they are,below the mark. 1879-80 . “| 3,724,128 Estimated. The estimate is based on the statement of a late Burmese minister, that about 15'6 lakhs of viss : or 3275 per cent. of the annual production were consumed in Upper Burma; the rest was exported to Lower Burma. The import of crude oil was registered at Thayetmyo, and this quantity was accordingly estimated at 67'5 per cent. of the total production, The production of Yenangyat 1880-81 . .| 4,434,865 is estimated at viss 100,000. 4 1881-82 , „| 3,416,234 Estimated, see note above. The import has, however, | decreased, and it only amounts to 61'5 per cent. of the total production. It is supposed that during 1882-83 . „| 4,221,630 these three years the proportion between con- | sumption in Upper Burma and export into Lower Burma did not change. Production of Yenangyat 1885.84 . «| 3,930,528 as before. 5% 1884-55 , ‚| 4,577,556 Estimated, if however the same proportion of con- | sumption and import (38:5 : 61:5) were used for the calculation of the production, the result 62 and 63 lakhs of viss per annum would apparently be too high. The ratio of imported oil must therefore be necessarily higher, and it is supposed that it is the same as in 1886-87, namely, 872 per cent. of the total production; this may be too much, and the actual production is therefore rather higher than the estimate, Production of Yenangyat as- 1885-86 , ‚| 4,528,667 before. P2 ( 257 ) 212 NOETLING : PETROLEUM IN BURMA. The above figures seem to prove that there was no great fluctu- ation in the production of oil previous to 1886, the production seems to have sometimes fallen, sometimes risen, but it has apparently never exceeded 45,000 barrels per year. In the following table the production is given for the calendar years 1886 to 1894— Barrels. 1886 . : e - x А 34,180 1887 . 5 5 Š : - 57,412 1888 , ë . ° ° : 62,721 1889 . " a ° - А 69,408 1890 ° ° ° . ° ° 105,384 1891 | . А ° - ° 137,882 1892 4 А - . . 2 201,188 1803. 4 . . : ° ° 240,141 1894 . . SN AE 257,290 As already stated the nam figures mark an enormous rate of progress within these few years, but what are after all 2 57,290 barrels compared with the production of Baku or America? For comparison I give below the figures of the production of the two most important centres, as far as I have been able to obtain them. Тһе figures for America are extracted from Stawill's 1 valua- ble book, and those for Baku from Erdmann's? interesting paper :— America,* Baku,* 188б^ а гк ee 28,064,841 17,857,142 ИТВ REED 19,642,857 / TC NNI os 27,612,025 22,797,738 1889 . 3 . : г - 35,163,513 24,285,714 ЗЕБ КА, ЧА 45,822,672 28,928,521 iSo ads ‘ - š 54,291,980 Unknown, Woe RM HTML ERES 50,509,136 2? 1893 à . . 4 . 48,412,606 “ke ee ) Mineral resources of the United States, 1893, p. 8. 2 Das. Kaukasische Erdól, Zeitschr. fiir Naturwissensch. Ap., LXV, 1892, * Production in barrels 42 imp. gallons. ( 258 ) Toer ` VALUE, 213 We see that in the face of the above figures the production of . Burma of a little over a quarter million of barrels is very insignificant. Even Galicia and Roumania exceed Burma in quantity; according to Hófer, the production of Galicia amounted to 571,538 barrels as far back as 1886, of Roumania 269,230 barrels іп 1881.2 The present production of Burma about equals that of Canada in 1886, the latter being on the fifth or sixth rank as a petroleum produc- ing country, and so far asis known to me Burma exceeds only a few countries, where the production of petroleum is of very minor import- ance. So far the dreams cherished by some, have not been realized as regards the petroleum prodaction of Upper Burma, although the most important field has been thoroughly tested. Whether the future will bring a change remains to be seen, but I believe this to be highly doubtful. CHAPTER IV.—THE COST PRICE AND THE TRADE VALUE OF THE BURMESE PETROLEUM. The trade value of the Burmese petroleum seems to have under- gone various fluctuations at different times. If Colonel Symes' state- ment is correct the value of the oil must have been trifling near the end + ofthe last century, as 200 or 300 pots were sold for one tical= R 1-4-0. I am inclined, however, to think that he must have been misinformed, because Captain Cox states that 100 viss were sold for 11 tical, say Ri-1o-o. As 200 or 300 pots contain at the lowest estimate, 2,000 or 3,000 viss, 100 viss would have been sold for less than r anna, which is so trifling a sum that it would have been entirely insufficient to pay for labour alone. For this reason I think Colonel Symes' state- ment to be erroneous and Captain Cox' figure nearer the truth. There is no further information about the value ofthe petro- leum till 1835, when Captain Hannay estimates its value at about R3 per 100 viss. In 1855 Captain Yule stated that the ordinary price of the article 1 Hófer, Erdól, p. 152. 3 Ibid. ( 259 ) / ` 214 NOETLING : PETROLEUM IN BURMA. used to be one tical per roo viss, but that lately, in | consequence of the demand from Rangoon, it had risen; at the price given of 155. per ton, the price of 100 viss must have been something like R1-8, This estimate agrees very well with Captain Yule's states ment of the value of the oil imported into Lower Burma in 1855, stated to be R21,972, which answers to a rate of about R1-4-0 per IOO VISS. The year following the visit of the members of the Mission to Ava marks a new epoch in the history of the Yenangyoung oil field ; the extraction of oil was declared a Royal monopoly. Hitherto the well owners enjoyed the full benefit of the sale of their oil, but from this time on they were bound to make it over to the king at the fixed rate of R1-8-o per 100 viss. We are luckily in the position to fix the introduction of the monopoly system very accurately. It did not exist in 1855 when Captain Yule visited the oil fields, but in a foot note, he says ‘ petroleum which has acquired a great additional value in consequence of the demand for the English market has recently been added to the Royal monopolies.” As the narrative of the Mission to Ava was published in 1858 we must assume that the monopoly was introduced in 1856 or 1857. This supposi- tion agrees perfectly with the native statement that in 1218 or 1219 of the Burmese era the king forced the well owners to sell him all their oil at the fixed rate of Е1-8-о per 100 viss. It is hardly a mere accident that the introduction of the petro- leum monopoly nearly coincides with the occupation of Lower Burma; we may even say it was a consequence of it. With the annexation of Lower Burma the demand for petroleum increased owing to the establishment of a larger export and with the increased demand the selling price naturally rose. The king quickly perceiving the advan- tage he would derive if the whole of the oil trade were in his hands, declared the oil to be one of the articles which, like rubies, were Royal property and could only be sold by the king ór persons author- ized by him. Whether there was a formal agreement with the well owners or not, is difficult to say. A Burman remarked philoso- '( 260 ) VALUE OF TRADE. ` | 215 phically, when I enquired about this subject that in those days they had simply to do what the king told them, and there was no remon- -strating against his orders. With the monopoly the price of the oil rose considerably, I cannot ascertain whether at once to its later figure oronly gradually ; from 1879 to 1891 the price was R25 per 100 viss brought up the river and R15 per 100 viss brought down the river. Afterwards the price for upcountry oil rose to R25, that for Lower Burma fell to R7 per 100 viss, but it subsequently recovered and till April 1891 the ordinary selling price of crude oil delivered at the river bank was R15. The local Government having given back the right of free sale to the native well owners the price of the crude oil dropped at once owing to the competition of the oil from the drilled wells and in May 1891 it sold for R2-12-0 per roo viss delivered at the river bank. The cost price of the oil is very low, and it seems that it has not changed for a good many years, but unfortunately no information may be obtained about this subject from previous accounts about the oilfields. Captain Cox states that four labourers were required to haul up the oil and that they received one sixth of the value of the oil drawn at the rate of r$ ticals per roo viss. This would roughly amount to 4 annas per 100 viss ; cart hire seems to have been paid separately, as Captain Cox states that the value of the oil is in- creased to three eighths of its value at the oilfields, the price at the river bank being 2 ticals (R 2-8-0). Should this be correct, the actual cost price per.roo viss was originally low, but was consider- _ ably increased by the cost of cart hire, which was something like 15 annas per IOO viss. In later years the actual cost price, including cart hire, was re- duced to 8 annas per 100 viss. It was supposed, that the man who carted the oil down to the river, had to provide also the labour of hauling up the oil. This was generally done by members of his family, and he received 8 annas for every 100 viss of oil, under the obligation, however, that he was to cart the oil down to the river, ӘБ Y) 216 NOETLING : PETROLEUM IN BURMA, CHAPTER V.—THE PETROLEUM TRADE. The subject treated of in this chapter cannot unfortunately be dealt with in so exhaustive a manner, as might be desirable, owing to the rather scanty information available. . It seems that up to the time of the annexation of Lower Burma in 1853, the bulk of the production of oil was consumed locally, that is to say, it was used for illuminating purposes to a small extent, but chiefly for preservation of the timber of boats, houses and monasteries. Small quantities may have been brought over to India ; it is, however, quite certain, that a considerable quantity found its way through the Shan States into Western China. It is very diffi- cult to arrive at a correct idea about the quantity thus consumed, At present the local consumption, including export to India, is some- thing like a lakh of viss per mensem; in 1879 it amounted to about 1} lakhs. If we assume that in former years the local consumption amounted to double this quantity, or 3 lakhs of viss per mensem, I believe we are very near a correct estimate. | | After the occupation of Lower Burma there seems to have been a considerable export of crude petroleum to England. Captain Yule states, page 20: “There is now a considerable export of the article ` from Rangoon to England and one of the Rangoon houses had a | European agent residing on the spot.” According to the same authority lbs. 6,679,140 = viss 1,830,000 passed the custom house at Thayetmyo from Ist February to ıst November 1855 on their way to. Rangoon. This would answer to an average monthly export of 228,750 viss; in round figures 23 lakhs of viss per month. Assum- ing that this quantity represented half the total production we arrive | at an estimated monthly production of 43 lakhs of viss, that is, pretty close to the same amount which 1 supposed to be the production in 1855. No more data are available concerning the import of crude oil into Lower Burma till 1880-81, although it is quite certain that - all this time considerable quantities of crude oil were exported пеш Rangoon to Europe. | (^ 202. ): PETROLEUM TRADE. 217 An enterprising firm, Messrs. Finlay, Fleming & Co., started a refinery at Rangoon, but it seems that up to 1886 the concern ` was not very profitable, owing most probably to the high price of the crude oil. After the annexation of Upper Burma a limited liability company under the name of the “Burma Oil Company” with a capital of £120,000 was formed which took over the stock and plant of the refinery, and owing to the lower rates at which the crude oil could now be obtained from the native well owners, business prospered. This state of things prevailed until March 1891, when the five years' contract, which the firm had entered into with the native well ` owners, came to an end, and the latter, apparently tempted by the . high price the petroleum had hitherto commanded (see page 215), refused to enter into a new contract on the previous terms. | In the meantime the Burma Oil Company had energetically pushed on the drilling of wells at Kodoung in the central part of the Yenangyoung oilfield, and having succeeded in turning out a larger quantity of oil than was required to supply the refinery in Rangoon, was in the lucky position of being independent of the supply from the native wells, The native well owners stubbornly refused to come to terms with the Company, hoping that they would now receive the R25 for which 100 viss of oil had hitherto been sold. But to their intense surprise the price of oil fell on the 1st of April 1891 to R2-12 per 100 viss, and they were subsequently only too glad, when another Company, the Yenangyoung Petroleum Company, Limited, offered to take the whole of their production at R4 per roo viss. .Any- body, however, who knew of the conditions of the production, could foretell with certainty, that this new undertaking could not possibly prosper, and after a life of hardly a year it failed, and matters Stand now exactly as in April 1891, if not worse, for the native well Owners, (263 ) .218 NOETLING : PETROLEUM IN BURMA. Т have now to deal with the various branches of the petroleum traffic, víz., local consumption, import into Lower Burma and export from Rangoon. SECTION 1.—THE LOCAL CONSUMPTION OF CRUDE OIL. As already pointed out it is very difficult to form an opinion about the quantity of the local consumption previous to the annex- ation of Upper Burma. For the three years following the annex- ation we may form an estimate by deducting the oil exported into Lower Burma, from the total production, the quantity of both being known, the balance showing the probable local consumption, The figures thus obtained are, however, not as correct as one might wish because this quantity represents the offtake of a local contractor who having made an agreement with the Burma Oil Company, had Secured the monopoly of supplying the whole of Burma and India with crude oil, The crude oil subsequently imported into Lower Burma and exported to India is included in the figures representing the import of crude oil into Lower Burma. The consumption of crude oil in Upper Burma, including oil exported to China, must therefore be smaller than represented by the following table. In computing these figures I assumed that for the period 1880-81 to 1885-36 one third of the total production was consumed locally, basing this assumption on the statement of the Burmese Minister above referred to (page 27). For the years 1886-87 to 1890-91 the actuals being known the figures will represent the offtake of the local contractor, which includes oil subsequently imported to Lower Burma, part of which was exported to India. From the rst of April 1891, up to the present date, no accu- rate figures can be given, because the native well owners have ` obtained the right of free sale, the local consumption is supplied by countless channels, through which the oil finds its way from the producer to consumer, ( 264 ) E N атақ Ж 3 T "Nm LE "TES | «PAM у ау Pu m » i ае ul q.” f di E N 52), | © F 20 ^ 4 E ү қ 7 М , e 4 "29 n e; ' rS d K PETROLEUM TRADE. 219 E n Table showing the estimated local ERS of crude oil from E, | 1880-81 to 1890-91. FINANCIAL YEAR. Viss of 3°65 lbs. |. ` 1880-81 : : a 4 У . . 1,508,831 1881-82 A A ERE o _ 1882-83 ET ° . . ° . 1,686,707 mt? 1885-84 AO : Í 2 А + 1,594,003 NEM - 1884-85 . ° ° . : ‘ А 762,695 ES 1885-86 ест ГЫРА лды УЛ РУТ Bw 1886-87 OC AH EMI CS cene" ` е Вт ^ CAM ` 1887-88 E WENT Qu cado nan Et. | 1888-89 |. d . ` 4 E ° 248,76o "E 1889-90 . БЕЛҮ. 42. 4475» . 1,742,662 SE 1890-91 . 4 : > š А Ç . 2,503.278 ` From the above figures we may assume that up to 1885 the local Е was something like 1 lakh of viss per month; during ` the years following the annexation, it fell off greatly, being a Bie more than half a lakh of viss. If we consider that the oil is 4 к used for industrial, not for illuminating purposes, we under- E ` stand that during the years of unrest which followed the annexation, | г the local consumption must necessarily decrease. From 1887 the Ж above figures show strange fluctuations which cannot easily be ex- | plained. It is, however, certain that with the return of order in | 3 Upper Burma, the local consumption greatly increased, and it is | ` certainly not far from the mark, if we estimate it at present between | 23 —3 lakhs of viss per mensem. Sscrion 2, -IMPORT OF CRUDE OIL FROM ee INTO LOWER BURMA. E The oil fields at present exploited i in Upper Burma being situated | = оп the banks of the Irawadi, there is only one way by which the E petroleum can be transported to Lower Burma and thence to М Europe, which is at the same time the shortest апа cheapest, vi2., the E river itself. Accurate statistics of the quantity carried down the 50% А ` river would thus be of double value ; if compared with the figures | 2 "I Retepresentiug the cuim of Ure from Se it would a Dr 2 | | PY i же d 220 NOETLING: PETROLEUM IN BURMA. a very fair estimate to be made as to the quantity of petroleum, consumed in the country in addition to that quantity of crude oil which has been consumed locally. The latter quantity could easily be obtained by deducting the quantity of oil imported into Lower Burma from the total production. i The foliowing table will show the import of crude oil into Lower Burma for the period 1880-81 to 1888-89, as registered in the custom house at Thayetmyo; unfortunately since 1889 the import traffic was | no longer registered at Thayetmyo, the figures for 1889-90 and 1890-91 are therefore estimates only, which are probably too low in the former and too high in the latter year ; since 189o, the petroleum imported into Lower Burma was again registered at Thayetmyo, and the years following 1891 give therefore the actuals again, Up to 1888-89 the custom house returns show the quantities in maunds at 82'28 lbs., from 1891-92 in gallons. I give the actual figures as obtained from the Custom-house authorities which I have converted into viss— چ ج 0 E‏ | | ) 266 ( | FINANCIAL YEAR, S IA а. Құм” 1880-81 129,801 2,926,034 1881-82 90,473 2,039,484 1882-83 112,451 2,534,923 . 1883-84 105,868 2,386,525 1884-85 169,230 3,814,861 1885-86 167,583 3,773,225 1886-87 138,372 4,246,369 1887-88 189,197 4,264,967 1888-89 274,352 6,184,570 1889-90 No record. 5,499,598* 1890-91 No record, 9,074,343® Gallons. 1891-92 3,587,419 8,541,500 1892-93 5,360,119 12,762,200 1893-94 7,331,483 17,455,900 PETROLEUM TRADE. | 221 If Captain Yule’s statement regarding the quantity of petroleum imported into Lower Burma is correct, there seems to be hardly an increase noticeable up to 1884. The import into Lower Burma would therefore have remained stationary for a considerable number of years, special fluctuations of course always excluded. This view is in some way supported by the returns for the period 1880 to 1884 which show only small fluctuations. From 1884 the import rose steadily, till in 1889 it had treble the quantity of 1882, or within seven years an increase of about 300 per cent. inthe quantity of petroleum transported to Lower Burma took place. Since that year the import has steadily risen, but during the last two years it jumped to the unprecedented height of 17,455,900 viss, that is to say, an increase of 600 per cent., as compared with 1880-81 is noted. | SECTION 3.—EXPORT OF PETROLEUM AND ITS PRODUCTS FROM RANGOON. | * Rangoon oil" has been known a good many years and has obtained a high reputation as a lubricant throughout the world, and it appears that the demand for it was always greater than the supply. The following table will show the export of mineral oil, including crude oil, refined petroleum, and paraffine wax, obtained as a waste- product in refining the crude oil. As all the petroleum destined for export (except such small quantities as go overland to China), has to pass Rangoon, the subjoined table will show the total foreign trade in petroleum from Burma. Table showing the export of Burmese an and other products derived therefrom, from Rangoon, during the period 1680-81 to B TODA -94. ExPORT OF MINERAL! ExPORT OF PARAFFINE OIL (CRUDE AND FINANCIAL YEAR, REFINED). Gallons at lbs, 8'83. | Cwts. 1880-81 . . . e ° . 217,625 Nil. - 1881-82 . . е 4 ° 237,440 13 1882-83 . IRET 4 ^ T 363,490 Nil. ( 267 ) 222 NOETLING : PETROLEUM IN BURMA. EXPORT OF MINERAL E xP OIL (CRUDE AND ORT OF PARAFFINE WAX, FINANCIAL YEAR, REFINED). Gallons at Ibs. 8:83. Cwt. 1883-84 . . А . . . > ° 355,529 | Ni. 1884-85 o.. o 2 қ А etree tise 495,763 321 1885-86 . i . . А ы . - 547,200 | 3,825 1886-87 . . - Š . ° А “ 492,269 4,339 1887-88 . А . ° ° . e А 626,216 5,757 1888-89 . ° " : AEN A ICI. [155 8x0 6,038 1889-90 . > - See А » e| <> 088,307 7,920 1890-91 + e : ° ° . . А 828,429 8,485 1891-92 | . А . А > A - 1,189,098 13,635 TEDR-0% s. + : А З : VM 1,335,506 21,278 1893-94 + ° А : е : 4 Е 1,522,981 28,858 This table shows that foreign traffic in petroleum has steadily increased, having risen from a little over 5,000 barrels in 1880-81 to 22,250 barrels in 1889-90, that is to say, an increase of over 300 per cent, during nine years, If we consider that during the same period the import of crude oil into Lower Burma had risen only about тоо! per cent. it follows that there must have been an increasing demand for Rangoon oil, etc., which had to be complied with at the expense of local consumption, a fact that will be further proved by the next table. During late years the export still rose, and the latest returns for 1893-94 with 38,166 barrels show an increase of 626 per cent. over those of 1880-81. Although in themselves highly satisfactory, those figures prove, however, how really insignificant the foreign trade in Burmese petroleum is: as compared with that of America ` or Baku. There 15 no doubt that the export is still capable of . expansion, but even if it double, the quantity of, say, 80,000 barrels . . would have not the slightest effect on the petroleum market of the world. The only effect would perhaps be, to lower its own selling 3s 44 v ) | price. Unless much richer fields are discovered, of which, however, | Qm is hardly any probability, the trade in Rangoon oil will remain | E its present modest, though profitable, position. = Ап interesting feature in the above table is the enormous E. increase of the export of paraffine wax during the period 1884-85 to a p. 1893-94 probably due to more improved methods of manufacture, The figures show some further interesting facts regarding the E trade of Burma. As the total production of crude oil is BE as wellas pe imports of the same into Lower Батша, апа the E way, і it is easy to ediculate the proportion these RAUS of the tup form to the total production, These figures will be found in the a following table, in per cents. of the total production of crude oil, "uf Total export : Import of Export of of mineral oil FiNANCIAL YEAR, crude oil into mineral oil and paraffine Lower Burma, | from Rangoon. | wax from | Rangoon, қ 1880-81 AER қ te ° ә 5 67`5** 11'8* 11:8** E ESSI-82 . - EM : > : 61:5* ОА XO SN | ў 1882-85 . > ° | А : - - 61'5* 20:8* 20'8* T БЕРЕ M russa a ЧАҢЫ ЛЫСЫ 2r5* 21°5** ES: ш oM o oso ғғ” 261* | rs ENS. 2.2... -- жг | ag 23. EC 1886-87 М» š а 2 ° А i 852 229 265 i E 1887.88 С . ° ° ° ° . 75'0 i} 26:7 29:8 | о аты» : MEAN à Ay A А 961 269 \ 298 | E 9 . .. . М е А e 75:0* 307 240 | 890-91 ШЕ” - Po at DERIT ç 4 90'5*** 106 224 5 ME СОХ руд ТАИС АШ 180 207 К Ж 1892-93 I . . . 2 | ° `. . 594 1470 18: o | ph. 1893-94 . . = а | а. . ° . 702 14° I 18: I * Estimate, ** No export of Paraline wax. *** Probably too Passen — 08 2 | | ( 269 ) Y ae ^ E O A S š PETROLEUM TRADE, | 223 224 NOETLING : PETROLEUM IN BURMA, As regards the proportion which the import of crude oil into Lower Burma bears to the total production, we see that it has undergone the greatest fluctuations. From 96 per cent. in 1888-89 it has fallen to as low 54'3 per cent,; that is to say, while in the former year nearly - the whole of the output was imported into Lower Burma, in the latter only a trifle over half of the production went to Rangoon. Since that time it has again risen, but amounts to less than three quarters ` of the total production. It is very difficult to explain these fluctua- tions ; in former years the balance not exported to Lower Burma was certainly consumed locally, that is to say, it was shipped up the river or carted inland and used for the various purposes to which the natives apply the crude oil. | At present the balance not shipped to Rangoon, by no means represents the local consumption, a certain quantity always re- mains in the storage tanks. During the last two calendar years the local consumption was more than 9 per cent. for 1893, and 6 per cent. for 1894, Of the total production ; but even if we add another 10 per cent. to the local consumption, and allow то per cent. for leakage | and what is by no means an unimportant factor in this hot climate, evaporation during the transport to Rangoon, the large deficiency in - some of the figures cannot be explained. Another remarkable feature is demonstrated by the figures re- presenting the ex port of mineral oil and its products from Rangoon. It is unquestionable that the proportion, which the exported oil forms of the total production, has been steadily rising till 1889-90, when it amounted to a trifle over one third of the total, Since that year it has been rapidly falling, till during the last two years it amounted to not more than r5 per cent. Itis evident that there must be an explanation for this remarkable decline, and in order to find this out, I computed the following table which shows the pro- portion the exported oil and its products bear tothe quantity of oil imported into Lower Burma is expressed in percentages. C 270 ) uw 22000 PETROLEUM TRADE, `: "225 марра س ا‎ «nte ———— oM. Export of Export of mineral oil Palance . mineral oil | and paraffine | Probably repres ë 5: 4 ағы senting local om Ra goon. | E | consumption, 180 ЕТ, . . A y . 281 28:1* š š * š ; 346 346% A 4 im : 366 4 36'0* 5 2 қ е 4 arı 326 | 684 лс ИТТЕН ger | 31 | бә ° . . . . 280. gri — -68'9 Dust E 355. 397 боз U A JA 28 0 31'0 боо ^ А : ^ ° No record. i : « . А . No record. . a . . 331 81 619 L4. SS ДАР PS ME 25'0 300 | 700 В š : Reeds К.т 207 , 258 742 e * No export of paraffine wax. > The table proves clearly that only a small percentage of the al quantity of crude oil is again exported from Rangoon, in any chiefly in the shape of Шы ашаа oil. This view is strongly sup- m when we examine the import of foreign mineral oil into | o 10 226 NOETLING: PETROLEUM IN BURMA. | Burma. This was imported to the following extent during the years noted :— FINANCIAL YEAR, | Gallons. 1890401. . = . e “ . 2,230,955 1801-02 . E - . 5 ° 2,453,108 1892-03 + ° з “ ° - 3,082,795 8058-04 vo. Mh RE O PES ES 2% These figures prove that up to 1892-93 the import of foreign ol steadily increased, but in 1893-94 it fell to the extent of almost 50 per cent. It is probably safe to assert, that this decrease is due to the increased local consumption of refined Burmese oil We know that in 1893-94, 7'2 per cent., say, 75 per cent. of the imported oil or about 53 millions of gallons, must have been consumed locally. If we suppose that from 40 per cent. to 50 per cent, of this quantity! has been converted into illuminating oil, the above would represent about 23 to 23 millions of gallons of illuminating oil, which represents about the figure by which the foreign oil imports have diminished, 1 See above, page 158: ( 272 ) SERRE SOUTHERN GROUP OF MUD-VOLCANOES, MINBU, IN 1889, LOOKING EAST. GEOLOGICAL SURVEY OF INDIA. DE Noetling. Memoirs, Vol:AXVILPt.2. PLL. Y Noetling. A — N33b N23a у NES Tali Diar т 5 Lit} Printed at the Geol. Surv. Office Jhan tandra Lith SOUTHERN GROUP: OF MUD-VOLCANOES, MINBU, IN 1889, LOOKING NORTH. "LSV3 9NIM007'688! М NANIN “SIONVITOA-ONAN 40 dnONO9 NYSHLNOS E MN Wd ZAS ПА XZ IPA OWN | : | TT VIANI 40 AHAWAS 79791907099 4. "prj apu) чеч деу RA FRAN ` 1SV3 9NIMOOT “5681 NI NENIN ÍSIONVITOA-ONAN 40 dnONH9 NYSHLNOS “040 “Aung Joan эца 1? PAULA oN (юс 1 , 1 I 1 $ 4 .. o N цат Pupueu) vey r ey 4i PISIS CONJQOÓH Tee EUER Ра 5 5 ә r A e, Memoirs, Vol:X XVII.Pt.2.P].IV. . 2 do SEC GS Burn EEE MS at the Geol. Surv. Office. “44 DE Noetling. Қа) Dhan Chandra Lith. GEOLOGICAL SURVEY OE TN DITA: yes SOUTHERN GROUP OF MUD-VOLCANOES, MINBU, IN 1889, LOOKING NORTH. Memoirs Vol: N XVII PU 2 PI IV. Printed al the Geol. Surv. П E 3 ы 2 г? e zu 201 i = “A ZZ Mu L Dale ° IN DIA. GEOLOGICAL SURVEY 0F PLV. 2 irs, Vol. XX VILPL. Memo Printed at the Geol. Surv. Office. Kali Dhan Chandra Li MUD-STREAM ON М? 5 MUD-VOLCANO. $ x Š > : E £ 8 = E E Ж - >< Ў E ч % 1 o Q > E < ж 2 O + E 3 "ч о "NC - m e > ° ^ = , ы L) т ol: < z 2 z ü о 5 < S ы - к Š - ° TA. ° { 2 J = IH : E | ° 8 ° A E E | A ¿ = š Е z < "а ы Ç e "ONVITOA- ANA S ¿N NO NMWV3%31S-GnNMW “091350 Amg TD эч! Te payag ‘HHT sapuwq) usu rey 4 ж ж.» E Im me Bu Ж. *"3NIAVY 3N38 3H1 NI GNW 3AISNALNI 40 SNI3A ' `9UJO "AMS oon әчү 12 Paqui] “UT PAPUPYD ueuq UP - ' * < ` y X \ ^ m PET "HIA Id g Vd IIAXX TOA лошәр | p `Эшцәоқ i k TM '"FIGNI ЯО AFAUNS TFOIS9O0' TOSS ` | | hr жа Kali Dhan Chandra Lith. nl | 5 | ІШ. N | [А l if ШІ | ШҮ m! jl | ч) \\ GEOLOGICAL SURVEY ОЁ INDIA. Memoirs, Vol: XXVII. Pt.2 PIIX. | 1 Ғы J J E KM A YENANGYOUNG OIL FIELD, VIEW OF THE EASTERN SLOPE OF THE AYATPOYO. ^ ny p IT Um Memoirs, Vol. XXVII. Pt.2. PIX. Printed at the Geol. Surv. Office. GEOLOGICAL SURVEY OF INDIA. DE Noetling- Memoirs;Vol. X XVII. Pt.2. PIX. Kali Dhan Chandra Lith Printed at the Geol: Surv, Office, YENANGYAT OILFIELD. VIEW OF THE EASTERN SLOPE OF THE TAUNGSIN RANGE NEAR YENANGYAT. GEOLOGICAL.SURVEY OF INDIA. | ` Mem. Vol XXVII Pt.IL PI.11. 36% ЕГУ 47. e Ф RD Y fus, Me С | NS Wh RN DI) | Ж = $ a = i M > 1 | 6 : : ER LA 7 / IN GE Ы | 15 o NGT > 2) l ES | KODOUNG YENANGYOUNG OILFIELD. Scale 8-1 Mile — = Fe ara ¥ Š we. Section XI | vnm B am vn 300. 400. High water level i] «100, 300, | 236. 5 i B 200... E | Sen level 100, E CES „200, LTE E мо. Section XE. 2 ТШ | High wotee Laval 4100; ТІ 100 ma, Nen lave E E тоо. 300 High wnlar lavet 100, E 00 Sea level ae 400. ооо High wate Neeti кише Section XVI. Section Vf. „son * 100), 300. whe High water level тоо g, Section. XVII. Г E 100, 7 Ea ДИ Sca level | 300. | ^ 26- | x гоо. н Section VIL мет Dm E (ao His š LL hah water larn ІНЕ duces Hk кезегіне. 100, 2 m T o, „Sen level e ES 5 | puc E зоо = Highwaler- level -200 100 s Seu -level NOITN ES A { E . тоо š 4 | С KO-DOUNG TRACT. | p ЕС | Бр 5 | КОА 2 " . 106 ” 1 „200 l 1 INDEX |” e не ТТТ E win | i E SEM Shale: e Clay ӘБ — a 2- RES [аве Section X Jo 3% oil rand. EA бала, dig. e ESSERE Sand, quero Ao oil sand- Do and, pelroliferous. PEE sand Seale 16 = 1 mile. ELE 400 300 High water level E оо Seu Leet 100, High water level 200) 7 LT 7 E 5554 iE SB ТАТЫ TU ШОН тнг Е | GEOLOGICAL SURVEY OF INDIA. й ң Mem, Vol: XX VIL.Pt.2.PL ХШ. south West. North-East. a 4 ЯЯ “7--.- Sea level » West. AN? 20. N? 47. Sect. XIX. 1050gall. 2100 gall. TE ie Hitt БЕЙ Sea level + North-North - West. 3 South -South - East. №011. №041. N221. IK 1000 gall. 2100gall. 1050 gall. < g Y m Eie s Е Sea level: North -West. { South -East. N218 N222. 812 (243. 958. N227, N226. Sect. XXI N° 66. 19. N? 11. 50 7 А 1. 250gaLL. 4200 gall. c z С н: 196 gall. 1000900. 756 gall. 4200gall. 500 gall. 4200galL 840 gal 52509 9 1 EEE Sand, dig БЕЗ Sand, aguderous. Exa Sand, petrolderous. EN Yonangyoung stage. WW Shales. LA Clay oli sand. 52) h...4* ou sand. i Clay. һ.5% ol sand. od “© ош xay. d.2 4 oil sand. e. Clog- f--3* ог А, ; Scale 16=1 mile. VA ^ ^^ А è x 4 P i £ А š 2 а , Р 1 he del бары” pA, dE А E > E. ы ы Ж” š M z у un cct AU X PRAE, AE EN MS < = = " жалы €x a АЕ "Ar Lyco бүр T MT ЖА c —— zc +e қ. — тт ы yw T 2 рые = T Ё, 2 > - Р 5 ; à ы É 4 А ¥ за — yo жж... 2 2а š 5 7 $c сыға ыма E Man, EF ° Du. “SM F , = a 4 : Š P ы = ; ` , X - - " 4 ск ' š -— . Y : А ` ` E x - ` x 3 * ` / N. | J a 4 il "t 5 - , | I > < i" E ‘ 1 x 2 | © . ^ i I s ы А f К P e Blocks 1S ------------- елесте Б Сурау ла Зай -------- № GEOLOGICAL SURVEY OF INDIA. | ^ | Memoirs, Vol: XXVIIEPU2.PI. XIV. Blooks IN 4 2N (beused Lo the Burma ОП Company) 000000002222. Twingon Native Reserve __ Ате» chiefly occupied by pit wells, Nusinye Twingon west villi Aungbanyo „Leased to the Burma Oil Company —_ — TA bes pet m Arew leased to the Sir Lepel Griffin Syndicate Aven chiefly occupied by drilled wells Beme Native- Reserve ; ! : c Blocks 15 & 29 N96 953 Ne»4 N°25 H E Area chiefly Bauen by pit wells 5 SSS а аа = š 1 Neve =p Southern branch of the Beman Cheung Beme villa E - —— c NE LONGITUDINAL SECTION OF THE YENANGYOUNG OIL FIELD FROM THE PIN-CHOUNG TO MINLINDOUNG. None 8- 1 mite Kyunbodoung The Yonangyoung. oilfield Scale 16 = {mile Pinchoung zz // СУУ 2222 >= SECTION N° 7 FROM KYUNBODOUNG TO THE PINCHOUNG. ~ Twingon Native Reserve: E Ares chiefly occupied by pit welle---- е 5 5 LE > SSS SSE Š < (IO ASSESSES SSS ` | RESERVE) im e “тен. chiefly oceupied hy pit мез... Twinfo eastern village | EN ай <: SECTION N2 5. ALONG THE AUNGBAN-RAVINE (SOUTHERN SIDE OF THE TWINGON RESERVE) Twingen western villuge Pagoda Memoirs, Vol: XXVII. Pt. 2.P1.XV. ШЕЛІ _ ІЛЕ ^ e кат” аж жейін g. š AA AV - —— | GEOLOGICAL SURVEY ОҒ INDIA. Memoirs, Vol: XXVII. Pt. 2.PL.XV.- ИИИ Вето ¡Native Reserve -. Ares chiefly occupied by pit wells Beme-yilluge <= < = ==> = = МЕ AS — SE SEEN DW NEON xe NST SECTION N° 4 ALONG THE NORTHERN BRANCH OF THE BEME CHOUNG (KHUNNHITSEYO) Mounfounggyawtheyo Thitchobinye == SE Ss < SES SS EE SER X= t SO SECTION М9 3. ALONG THE SOUTHERN BRANCH OF THE BEME-CHOUNG (TOUNGLE - YO) Minlmdoung Tounznigale Yedwenampyo SS SAN’ A SECTION N° 2. ACROSS MINLIN-DOUNG AND YEDWINAINGYO. Weat КЪР ЭА Ж кк ne W; Ko S e : Boat. Nulandaung Singu - choung A CROSS-SECTION OF THE YENANGOUNG-ANTICLINE AT SINGU. Scale 16 inches = [ mile + рте мех ios RAR: “ee j a s RAP, Ihe “м/м Memoirs, Vol:XXVII.Pt. 2.P1.XVI. -- = کے == - == 4 re 7 “ AS 7) EEL ate pagoda Minbu (Eur opean quarters) Iraw adi | ü im. PERA South GEOLOGICAL SURVEY 0F INDIA. Memoirs, Vol:XXVII.Pt. 2.P1. XVI. “CROSS SECTION OF THE YENANGYOUNG ANTICLINE AT YENANGYAT SOUTHERN SIDE OF THE YANAUNG CHOUNG RAVINE Scale 16 inches- I Mile East Trawadi CROSS SECTION OF THE YENANGYOUNG ANTICLINE AT YENANGYAT . East NORTHERN SIDE OF THE YANAUNG CHOUNG RAVINE Seale 16 inches = 1 Mile Ж Z 3 ж E wet 225 Ly My rawa б WU ¿ Z Г SECTION N° 1 FROM KYAUKTAN- VILLAGE, ALONG THE SABWET CHOUNG TO MINBU Seale 16 inches = 1 Mile Sckkate pagoda Minbu (European quarters) ^ Irawndi LONGITUDINAL SECTION THROUGH THE SOUTHERN GROUP OF MUD VOLCANOES NEAR MINBU AT THE BEGINNING OF 1891. Scale. [- 40 feet South. N° = TE ¿ P є ¿ i ! s * 1 ж > ' ' % `. ү f 4 ` = - " 23 es N E er [4 ht? Ри А ` “ ъ de ‚Ж x i š А ' [ ——M——— a WAP amm ovn Memoirs, Vol: XXVII Pt.2. PL XVII. East + 600 + 500 + £00 + 186 300 + £00 500 + 700 * 800 OILFIED GEOLOGICAL SURVEY OF INDIA. 1 қ Memoirs, Vol: XXVIILPL2 РІ.ХУІ. 4 Signal. post Shave Милат Pagoda East . soo - 500 * 400 - 200 Highwater -lexel 240 E Р Ў - Z š = 200 ^ 100 0 Sea-level = 100 + 200 NS E * 200 TU. (9) - 500 * 600 "У ой Sand. * 700 ШЙ SECTION OF THE BORE HOLES IN THE YANAUNG CHOUNG RAVINE, YENANGYAT OILFIED Scale 16-1 Mile | Calcutta 4 O S. 1 itho., ` la. -Ii Photo А Z > 3 ⁄ 0 n I^ Md vel CHE у / f 07 , j d / қ o, RÓS : Z P YES Yo OID INGLE, Z YA Reg. GEOLOGICAL SURVEY OF INDIA. Noetling. 2. Memoirs, Vol. XXVII, P: 1) SW. SIZ Бы 1 FIELD ШЕ i 2000 = 1 Mile. Men 2 1000 idena & lppmpelcunus ёггюнчийіенія) топ antilopinum & decrotherium perimense) one C Seale 4 Inches 509 RY Map of the ° acrnlotones with numerous Jonnil болга. > > - Mo 4 “ оо Conglomerate 5-4 Brown clay & Sanditons with Selenite. ~~ иди" racelheN unt — - — Grey yy (Lane Sf tile TER llore Ed (Zone ¡Zane W YENANGYAUNG OIL SS ES NS ENS |! Photo-Léthy., 8. I. O , Calcutta Reg aê, Du , God. Sur.-July 96-485. 4 . E E = К 5 Е 4 Ж 7 А 2 S A ) کد‎ m x ] vr А ' 52 E . > Ç 4 ( ¿ А бас NUNT. “4 Г А. ks ^ RC IMP) NR Aa РТУ жм ER E mos > 1 te B É ^ Ah мы "e. i ы % 4 М 7 ` 7 55 ` Е T 2 : + pasts я = ret 2 E . 5 М k ` "à. - CE қ Es i қ | те, b ю Fi H A М. pwe š aem 297 < 4 д $ АА б г с қ Y a ë = 4 - & “ aan 4 e Mn E 2 е”? "EE: 5; pi 2 ОАР AN RT аңы RES M pu neo و ےہ‎ en SMITHSONIAN INSTITU L T 3 9088 01311 6074 zn ==) —