Columbta Gnitversiy | in the City of Mew Pork 74 7. “Se } 5 4 LAMONT GEOLOGICAL OBSERVATORY e ee vee NN ie Lela ak a Aldi 0 That Hed 2) DES / Vs f PALISADES, NEW YORK age Td _—=a\ Technical Report on Submarine Geology No. | Sediments of the Atlantic Ocean LAMONT GEOLOGICAL OBSERVATORY oeaiN (Columbia University) Palisades, New York Ea Gl. hy Technical Report Number 1 CU-4-53-N onr266(01)-GEOL, Sediments of the Atlantic Ocean MBLWHOI Libra by 0030110001186 til David B, Ericson This report is a brief summary of the present status of research on deep-sea sediment cores and dredge samples from the Atlantic Ocean brought together at the core laboratory of Lamont Geological Observ- atory (Department of Geology, Columbia University). The research constitutes a part of geological investigations of the earth with the ap- plication of the methods of physics, chemistry, mathematics and en- gineering carried out by Dr. Maurice Ewing, Director of the Observa- tory, and his co-workers, The research reported in this document has been made possible in part through support and sponsorship extended by the U.S. Navy, Office o* Naval Research, Contract No, N onr-266(01). November 1953 ~ ee * See mass ni ee 4 - tes . * ACKNOWLEDGMENTS The writer thanks Dr. Maurice Ewing, Director of Lamont Geo- logical Observatory, for the opportunity to work on the unique collection of bottom samples which is the subject of this report, He is grateful to Dr, Walter Bucher, Department of Geology, Columbia University for valuable advice and encouragement, He is in debt to Bruce C. Heezen, who by combining knowledge of ocean bottom topography with theories of sedimentation, has taken many particularly important cores and dredge samples, Without the loyal help of my assistants GUsta and Janet Wollin this research could not have gone on, They have taken part in all aspects of the work from the construction of core racks to detailed analyses of foraminiferal assemblages and have supplied a multitude of invaluable ideas together with the energy and ingenuity to put them into effect. To others associated with the Lamont Geological Observatory who have aided directly or indirectly in this study the writer gives his thanks, “ait testes be eoesonis ‘geil sate aa ate sci oa WW olan api oft wo Sra of ton-oaso saa eintevneng® estge eae aid to zostano elt ok antigo cnensod < gHal? iw fof ER) “cept to snorarnagot wpadoutl gate va er tcaan © e att at oh ah. sipomiage yout bre outvbs sii bo matiod arene b> egpotwosl weiaidine> v6 oa wena 2 rowel i: ore oki ae Sines lk Da ae coe © advogne Me a ¥x09 sto) owed yautt sto aay ved gon bind A lo teen onc soit i i tow sunk “y sideutsvat Yo oman 9 bottsare vat bas sugitamons aoe oe sud! eg of yimagn bas yet oni din “Avge © — tromad aa fiw 8 batoieonen omeae shed? TABLE OF CONTENTS Acknowledgments Introduction Preparation and Storing of the Cores Prelirninary Investigations Transportation and Deposition of Sediments Turbidity Currents Cores from Puerto Rico Trough Cores from Northwest Atlantic mid-ocean canyon Evidence in cores for turbidity currents in the cable break area Micropaleontology, Stratigraphy, and Pleistocene Climates Recent distribution of planktonic foraminifera Climate determinations by planktonic foraminifera Climatic Optimum Diatoms Kadiolarians Poilen Sediments older than Pleistocene Geochemical Investigation Carbonate analyses Natural radiocarbon (C 4) measurements Ioniuin method Absolute surface area studies Paleotemperature determinations Organic content Chemical and spectographic analyses Physical Measurements Mechanical analyses Density measurements Soun? velocity measurements Petrography Clay minerals Volcanic ash zones Meteoritic dust Rocks Publications Page 12 14 15 16 20 20 Zl 21 21 23 23 23 23 24 24 24 25 Zt 27 27 27 30 30 31 31 31 34 ‘m | isch | & soca an and aia ify ‘ei deeb went ; “sapnoteiot’t wads ‘pble simpentbe® aed bt =“ f * 4 ; j : ; ia ; , Lo faery INTRODUCTION A large collection of deep sea sediment cores has been brought to- gether at the core laboratory of Lamont Geological Observatory, Columbia University. There are over 700 piston cores, 350 trigger-weight cores, and 250 camera cores. The total length of the cores is more than 2400 meters (7870 ft.), individual lengths varying from less than a meter (3 ft. ) to 13 meters (42 ft.). The majority of the cores are raised from a depth of more than 2000 meters (1100 fms.) and some from such a great depth as 7970 meters (4360 fms.), The cores are obtained from all over the Atlantic -- from the northern part of Greenland Sea to south of the Tropic of Capri- corn and from the Eastern Mediterranean to the western part of the Gulf of Mexico. Figure 1 shows the majority of core stations, In addition to the collection of sediment cores there are about 100 dredge samples with a total weight of over 2 tons. The core collection is unique in several aspects. The cores have not been obtained at random during a single cruise. They are the product of 37 cruises* made at frequent intervals over the past six years. Therefore most of the cores have been raised with full benefit of the knowledge of local submarine topography acquired on earlier cruises. Several series of cores have been obtained particularly to test specific theories in regions known through previous coring to be critical. *The greatest number of cruises were carried out by Drs. M. Ewing, J: L. Worzel, and B.C. Heezen and their co-werkers and were supported by ccn- tracts with the Cffice cf Naval Research and the Pureau of Ships, U.S. Navy. Three cruises were sponsored by the Natioral Geographic Society, the Woous Hole Cceanographic Inctitution, and Colurasia University. From 13 cruises carried out by U.S. Navy Hydrographic Office 92 piston cores and 21 trigger- weight and camera cores have been obtained. swe 4 sean thtqudivans f Be Many of the cores are from areas of rough topography. At these core stations the cores obtained were often shcrt, the coring tubes were bent, and sometimes the coring apparatus was lost. The scientific informa- tion, however, from that type of coring is of outstanding value. The collection is not a finished series. A campcign of coring has been tentatively planned for the coming year. The research on the cores has led to several conclusions, prev- iously published and summarized in this report, regarding the processes of sedimentation, the sediments themselves, Recent and Pleistocene stratigraphy, submarine erosion and the combined effect on ocean bottom topography. The importance of the nature of the sea bottom in relation to the transmission and reflection of sound which has significant Naval applications has also been shown. It is hoped that the research on the present collection of cores and new material will also add to the knowledge of the structure of ocean basins, the origin of continents, the chronology of Pleistocene climatic changes, diagenesis, and the origin of petroleum, The results of this research will of course influence the concepts on sedimentation applied by geologists working in continental areas, aida il ste0k jae cy push al sib bel Las reibaptatiso toe ad: i hb to agus + 1 clot orem igtaw ily: ia eel bested ) ee wits ah wong, vepatrieetaisan levavon oY bel ‘noe S709) co a0. We dobcrdong ee qotionoget togor ibd wee pel aitnintels et Sat shows ete vavrniaull ane i ications Hehehe antiege ae oll: : Seaidenen is als fo, a ieora Sy iobleee bin at tenn: won rie @ bas wks. ye mokioull a. tenn nies, ade icy doraonen ett acy Samos i. te eto OUHE, ott oe gh im saoqisads seinen aes ws iii Py. Bey mele od watnanino te ite econ me ” ws lanes wt owstoniog to nase nit ben ay 0 dageotten elt soeauttick atone Fasnoniaae> st Zz = Ww oO w Oo. : = O Sm rE EF 2 :. Sees i et tae 4 2 F oF Spas 3 at oO Sree to) Ea 3 ac fo) Zz PREPARATION AND STORING OF THE CORES As soon as the cores arrive at the laboratory they are unpacked, extruded, split, photographed, labelled, sampled, and stored, From all the cores samples are taken for preliminary rmhicroscopic investigation, and from some cores samples are taken for density determinations, sound velocity measurements, he determinations, paleo-temperature determin- ations by the oxygen isotope method, CaCO3 determinations, and other chemical analyses. For the preliminary microscopic investigation 8 gm samples are taken from a quarter section of each core at 10 cm intervals down to 50 cm. Below 50 cm, samples are taken wherever there are changes in type of sediment. In cores of uniform lithology samples below 50 cm. are taken every 50 cm. The sampies are dried, weighed, and washed on a 74 micren sieve. The fractions retained on the sieve are dried, weighed, and the percentage ci matevial coarser than 74 microns is calculated. The coarse fractions so obtained are examined and then stored in vials for future research work. Halves of the piston cores which are 21/2 in. in diameter are stored in rectangular 8 ft. -long metal trays. The quarter sections from which the first sampling is made are stored in cardboard boxes. In order to preserve a part of the cores in the original condition, quar- ters of the piston cores are stored in glass tubes. Formaldehyde is then dropped into the tubes to prevent moulding and the tubes are sealed with rubber stoppers. ya of ome dabecition te Sal Ay ac arg & jah Oh lava a woke yep igs as We 20 The trigger-weight and camera cores (short gravity cores 1 1/4'* in diameter) having been split and sampled are stored in the plas- tic liners in which they were raised from the ocean bottom, PRELIMINARY INVESTIGATICNS A general description of each core is made shortly after split- ting, while it remains moist. This is in the form cf a core log on which lithological charges are noted. A preliminary microscopic investigation is made of all the washed coarse-fraction sediment samples obtained in the way already described. The samples are examined for foraminifera and other or- ganic remains, Where possible climatic changes are inferred from the vertical sequence of foraminiferal assemblages, and these changes are plotted on the core log. An estimate of the relative abundance of mineral particles to organic remains is made as well as a rough description of the mineral species present. Further study of any particular core de- pends upon the information yielded by these preliminary examinations. The main purpose of the preliminary investigations is to obtain a maximum of information with a minimum delay. The results are rapidly given to the expedition leaders so that various points which seem to be promising can be further explored by more intensive coring in certain areas. The value of this method is well illustrated in case of the rela- tionships of submarine topography and sediment type. Preliminary in- Ewe wha tind i sino sidiwden seat 4a ume fee kationrok te: jai sr ae at a Babak « ob oresn nistubrned Yak ie yond WoW T ANvaeeg watvoge Wasi A>kdW etutom oHdisA” fot OR 8. vestigation of 2 cores from the Bermuda pedestal revealed tertiary sedi- ment. Ona subsequent cruise a number of cores were taken from the same general area and outcrops of other tertiary stages were found, (Ericson, Ewing, Heezen, 1952) Da The probable importance of turbidity currents as transporter |“ = of sediment into deep water was first indicated by a study of the relation- : hy — ship between sediment type and thaoaneiplty in the Hudson submarine can- yons region (Ericson, Ewing, Heezen, 1951). After a few cores indicated the probability that sands and gravel were limited to the canyon floor on / the continental rise and that normal clays were found in the inter canyon areas, about 30 cores were taken at topographic locations selected so as to confirm or refute the prediction. These cores not only confirmed the predicted occurrence but of 20 cores, taken on the same cruise in order to determine the possible existence of a delta, 18 contained sands thus confirming this additional prediction, The criginal puzpose of most core studies was the determination of a Pleistocene stretigraphy in marine sediments beneath deep water where it was supposed that only slow deposition occursed without inter- ference by erosion, slumping or periods of rapid deposition. The studies have demonstrated that while there are many areas where such undisturbed sedimentation occurs there are probably as many areas where it does not eccur. Therefore in order to obtain cores suitable for study of Pleisto- cene chronology cores must be taken from areas which seem promising in the light of the analyses of cores from previous cruises. Aerie wine 3 bore gone owoat eaitnibong ” ses _nebtanicossieb ds Bow psibee oes veonn ll naoq tiny Bi gio ode otaw om dianand atmacn boy exited. oh heneaits wan enrnorel ' notte dt paneanion Iria hs soot “ai amaie otters av ‘ton Aneh Mh oxaty anane adi: a6. yidudong on8 wyet | eatin to owls 202 dation Aores 2 nino ot a oon 3 Ny AN Quick studies cf a great number of cores make possible the gathering of material for a more detailed study of a specific problem. The relationship of deep-sea areas and the neighboring continental areas in selected regions can be studied in detail by a comparison of the sedi- ments of both areas. The general horizontal and vertical distribution of a few selected species of foraminifera within a great number of cores com- bined with data on the ec ology of these planktonic animals gives the key to the lithogenetic interpretation of older foraminiferal sediments which is needed for every kind of continental survey in areas of sedimentary rocks, Since generalized assumptions on the bottom sediments of the Atlantic Ocean based on incomplete data play a big role in numerous world-wide geologic problems, it is important to obtain more data as rapidly as possible to test these assumptions. A practical example has been furnished by the study of the cable break area south of Newfoundland (Heezen and Ewing, 1952; Ericson, Heezen and Ewing, 1953), ~~ J a 10. TRANSPORTATION AND DEPOSITION OF SEDIMENTS Turbidity currents. It has been found that beds as much as 10 feet thick of fairly well sorted sand are of frequent occurrence in sediments at abyssal depths hundreds of miles from the continents. Evidence in the cores indicates that these sands have been laid down in water of essen- tially the same depth as that which now covers them, Characteristic minerals and organic remains in the sands point to the continental shelf and slope as the sources from which the sands have been derived. The fact that sands and even gravels are found in the bed of canyons, but neither on the sides nor the divides, indicates that these coarse clastic sediments have been transported along the canyon beds by some kind of gravity induced flow. Transportation by turbidity currents seems to account for all the observed facts. This evidence for transportation of large volumes of sediment by turbidity currents through the canyons gives strong support to the theory that the canyons themselves have been eroded by turbidity currents, Cores from Puerto Rico Trough, Since the flow of turbidity currents is determined by bottom topography, it is becoming more and more possible to predict the nature of the sediment in a given area from a knowledge of the bottom topography. One of the first of many examples for testing this theory was a series of cores taken in and about the Puerto Rico Trough. The result was a complete confirmation. Two cores, about 25 miles apart, were taken on the flat floor of the trough at 7970 m, (4360 fms.) depth. Both 1l, contain a top layer about 15 cm, thick of "red'' érbrown clay. The aver- age hanes carbonate content of this layer is 0.5 per cent. Below this normal top there are in both cores three graded layers, one of which is about 200 cm, thick, The uppermost part of this graded layer is composed of clay-size particles, and is distinctly grayer than the normal top, but it is in its carbonate content of more than 36 per cent that it differs from a "typical" deep-water sediment. Downward in this layer there is a very gradual increase in particle size until near the base it becomes well sorted calcareous sand largely composed of the tests of planktonic and benthic foraminifera, small pteropods, and alcyonarian spicules. The carbonate content near the base is 74 per cent. The very shallow-water origin of some of the material is shown by occasional par- ticles of Halimeda. | The shorter one of these two cores ends at 280 cm. still in well- sorted material of shallow-water origin. The longer one at 295 cm, re- enters normal clay of abyssal facies and a carbonate content of 0.3 per cent, thereby disposing of the theory that these layers of shallow-water material are evidence of a recent and sudden subsidence of the floor of the Puerto Rico Trough. Two cores taken on the northern side of the trough contain only red clay, although the thicknesses penetrated are 185 cm. and 290 cm. Another core from the top of the ridge north of the trough is of "deep- water'' facies throughout its length of 260 cm. in spite of the fact that the depth here is 5,011 m. (2740 fms.), that is, 2900 m. (1600 fms.) shallow- er than the bottom of the trough. 4 ih ARE ene iia a i eh (7 ( 12. Cores from Northwest Atlantic mid-ocean canyon, Cores taken in and nearby Northwest Atlantic mid-ocean canyon have given more evi- dence of the important role the turbidity currents play in the topographic evolution of the deep-sea basins (Ewing, Heezen, Ericson, Northrop, Dorman, 1953). In one of two cores from the canyon bed the upper 123-cm. sec- tion is composed of clay and silty clay in part as graded layers. This overlies 2 1/2 meters of well-sorted fine sand, In the other canyon bed core only 2 meters of core were recovered, consisting mostly of graded beds of silt size. There is clear evidence that about 2 meters of sand were lost from the bottom of the core. A third core from the nearly flat western bank, 90 m. (50 fms. ) above the canyon bed, contains numerous graded layers which show that fully three-quarters of the 4.6 meters total thickness was deposited by turbidity currents. Fine sand makes up only 3 per cent of the total thickness. It is inferred that the sediment deposited on the canyon banks was carried in the highest part of the turbidity currents. Evidence in cores for turbidity currents in the cable break area. In ''The American Journal of Science", December 1952, Heezen and Ewing concluded that the breaking of all submarine telegraph cables in sequence from north to south following the Grand Banks earthquake of 1929 could be explained satisfactorily only by supposing that a turbidity current generated in the epicentral area flowed southward, breaking the cables as it reached them. 13, In the same issue of "The American Journal of Science" Kuenen discussed the magnitude involved. From the volume and density of turbid water necessary to account for the high velocity indicated by the timing of the cable breaks, he calculated a thickness of between 40 and 100 cm. for the graded layer of relatively coarse sediment which Heezen and Ewing assumed would have been deposited over a wide area south of the cable breaks, Since the appearance of these papers a series of cores have been taken across the southern part of the area affected by the supposed Grand Banks turbidity current in hope of confirming the predicted layer of sand which should overly more "normal" sediments. Three of these contain a layer of graded silt and muddy sand overlying foraminiferal clay of abyssal facies, Recent deposition of the graded layers is indicated by absence of abyssal sediment overlying them. The thicknesses of the layers are 2070 and 130 cm. A fourth core which is from the center of the cable break area is composed of 30 cm. of gravel and very coarse-grained sand. Therefore, it is concluded that the independent evidence afforded by the cable breaks together with the evidence from the cores confirming the presence of the sand layers add up to proof of the reality of turbidity currents as powerful agents of erosion, transportation, and deposition of sediment. ine tides os to woe sane obhy 5 ty eee Weave iy Tena i i hevdeh eae “wane Bade phyodte gihylanite taocnihyon, kpwwrci hs ic ve toch ak a ae i Bp fx 14. MICROPALEONTOLOGY, STRATIGRAPHY, AND PLEISTOCENE CLIMATES For the micropaleontological analyses the best species of pelagic foraminifera for a stratigraphical correlation were selected. These were found to be; Globorotalia menardii, G. men, var. tumida, G, men, var. flexuosa, G. pencticulata puncticulata, G, puncticuiata hirsuta, G. truncatulinoides, G. scitula; Globigerina inflata, G. bulloides, G. pachy- G. conglobatus; Globigerinella aequilateralis, Orbuiina universa, Pullen- iatina obliquloculata, Sphaeroidinella dehiscens. It has been found that foraminifera other than those listed, and radiolaria, pteropods, and coccoliths are so far not suitable for a quick micropaleontological analysis of the cores. It is evident that any faunal characteristic which marks a thin layer of sediment in such a way that it can be recognized in a number of adjacent cores may be of use in comparing rates of deposition from place to place. Furthermore, if the layer is not too old, a single radio-carbon date may be used to give absolute rates of deposition in a widely scattered suite of cores. With this object the coiling directions of several species of Globorotalia were studied in dees. It was found that layers only a few centimeters thick are marked by abrupt changes in ratio of right coiling 1. Bolli, H., The direction of coiling in the evolution of some Globoro- taliidae, Cushman Found, Foram. Res., Vol. 1, parts 3-4, pp. 82-89, 1950. Aah oivabrotaakads gen . ne te os at naden-viber « ota * tite oat ton “ vor oa Mt orenn soit 5. to left coiling individuals of the widely distributed planktonic species, Globorotalia truncatulinoides, The effectiveness of this method of recog- nizing isochronous layers in groups of cores is shown by figures 2, 4-B and 5-B, Recent distribution of planktonic foraminifera. With Dr. K. K. Wang, Brooklyn College, work on charts showing present distribution of planktonic foraminifera in the North Atlantic is in progress. It is hoped to have the charts ready for publication in the near future. Knowledge of the present distribution of these species is essen- tial to correct interpretation of the vertical faunal changes in long cores in terms of water temperature and oceanic circulation. In order to be quite certain that the material described is truly Recent it is necessary to use top samples which have been relatively un- disturbed by the coring tube and which have not been permitted to become mixed in transportation to the laboratory. To this end it is customary to take short gravity cores in plastic liners by means of a corer attached to the trigger weight which releases the large piston corer. In description of the Recent fauna the tops of these short cores are used in preference to the tops of the piston cores. Tentatively, two of the conclusions of the work on present distri- bution of planktonic foraminifera are: 1, It is generally true that planktonic foraminifera are tempera- ture indicators. But precautions should be taken when a species is widely distributed, and the area involved is of such great extent as' the Atlantic Ocean. For instance, Globigerinoides ruber is generally considered as a as wan ve , en pew ss by agiautesdose dearest fick seme nye Taal Shope slaps A i) ‘i B aaaee ite m sen te tow ae foo wrbhewntt ii i ey raion va sinosinaty ) Figs 2 - CORRELATION BY COILING DIRECTION of Globorotalia truncatulinoides A18)9-39 R5-54 3470 meters 3295 meters West East 27.7 Km WUHAN e Left << (15 miles) “i 175 meters Left 50/50 Right ) 50 ee ed yp: 1 meter ih 50 Se na _2 meters Location; 220 km or 120 miles SSW of Hierro, Canary Islands, and 400 km or 215 miles WNW of Oro River, Rio de Oro. From the correlation: it is obvious that the upper 180 cm section of A1l80-39 is the time equivalent of the upper 100 cm in R5-54, In other words, the rate of depo- sition at A180-30 has been 1. 8 times as fast as that at R5-54. Both sections are composed of uniform foraminiferal lutite, quite without any silt or sand layers, Thus there is no obvious évidence of turbidity current deposi- tion which might explain the difference in rates of deposition. Evidently the difference in rate is not a consequence of relative distance from the source of terrigenous sediment because the more rapid deposition has taken place at that station which is more remote from the African coast. . There is no evidence for greater productivity of lime secreting organisms at A180-39, Not only is the CaCO 3 content of the two sections very nearly the same, but foram tests ectually make up a larger fraction of the sediment in R5-54 where deposition has been slower. That the more rapid deposition has taken place at the deeper station suggests that turbid water flowing along the ocean floor has been channeled by local topography. Whether the greater density of the water so flowing is due to the turbidity itself, or to higher salinity, lower temperature, or a combination of all three is a question. Whatever the cause, a low velocity is indicated by absence of well sorted layers, and tairly continuous flow, by the lack of distortion in the coiling curve of A180-39 as sompared with that of R-54, 4he importance of this process of transportation and deposition as a possible ex- planation for the extraordinarily smooth and nearly level plains of sediment known to fill many depressions in the North Atlantic basin needs no emphasis. ; : a agit mie) to AOITOG MVC OMI vat HOTT A tAMHOD ae HO i Skah a ute . et aman secisleninicnleanaiale at ilies A avenge ahi vite is lira GL p74 argent OTs Se ona f j le ou ari 8 eee ah eee Ms Hi sett Sere i % eee abel youre eressilt to ‘vee anne G31 ve cof OG ord ab of yweVhd ox te Www olin S15 «0.08 OF ‘eoate toltows cro O81 veqyy oett tarts etrtinde ty et i oniielerses gy Digvmtuan ‘atee ott alvnwer eee ae be OH ci coro O01 sampqr edt Yo pmoled iy ween et ta Feed wie Soresky oe wnad wih bette tio mn oh Gonetanapenes evetittege ive beneqenen wen wane yathh “aoe o meine seni Om et celle nad'T “04a =e yin iit np png swomngherns ‘her cone - saiettegiirl nti pp ery 4 On 16, warm water indicator and not to be present in typical cold water samples. Yet it occurs commonly in the same area where Globigerina pachyderma is found abundantly, and Globigerina pachyderma is generally accepted as a cold water indicator, 2. From plotting of the data and drawing of a generalized dis- tribution chart a definite pattern results, showing that the distribution is closely related to the warm and cold currents in the Atlantic Ocean. Recent distribution of Globorotalia menardii in the North Atlantic and the Caribbean as known from 400 widely scattered cores indicates that the clockwise current system of the North Atlantic is a more important factor in the distribution of the species than temperature alone. To check the correspondence between the foraminiferal tests in the top layer of sediment and the animals actually living in the waters above, 210 plankton tows were made during a recent cruise, Data from the plankton samples will make a valuable supplement to the study of the core tops, Ina study submitted as thesis for the degree of Master of Arts to Columbia University, Mr, Julian Kane made a preliminary survey of the distribution of planktonic foraminifera from top core samples, Climate determinations by planktonic foraminifera, With the probability of establishing a standard section of Pleistocene sediments about 350 climatic curves have been drawn based on the proportion of the number of warm-water to cold-water foraminifera in samples from about 350 cores, Cores with evidence of turbidity currents, erosion, slumping, and re-worked older sediments are not suited for these determinations, . ae r z ‘ oes ; é * F : : A 5 - ~ 5 ea S og e 3 a? 2s 5 5 . ‘ Y 5 ot 56 s , : 5 . mE, . . = Be © : oe ™ i 5 i : S > . "i Be : Ps = - + ° , - oan oF J "4 ta a : : e ou + 3 - eae 0 « me 4 . “ av oo oats M He a5 =e ° : A a e 3 5 . - on 3 Pe 2 - ree as re 7 a4 i : = - . i f ie a Bee ay 5 4 s -! ‘. a 17. The most important warm-water foraminifera are considered to be Globorotalia menardii, Globorotalia menardii var. flexuosa, Pullen- iatina obliquiloculata, and Sphaeroidinella dehiscens,. The most important cold-water foraminifera are considered to be Globorotalia scitula, Globigerina inflata, Globigerina bulloides, and Globigerina pachyderma, Figure 3 shows an example of a climatic curve, The core, A172-6, is from the crest of an eastern extension of the Beata Ridge in the Caribbean (14°59'N, 68°51'W), The length of the core is 9.35 m, and it is raised from a depth of 4160 m, (2275 fms,). The core is com- posed of uniform foraminiferal lutite and gives evidence of continuous normal deposition. This core and five others taken along a NW-SE profile from Hispaniola to a point north of Aruba show satisfactory correlation of climatic zones as deduced from the planktonic foraminifera, All pass through a zone of cool-water species corresponding to the Wisconsin glacial stage and into a zone containing a warm-water assemblage char- acterized by an abundance of Globorotalia menardii flexuosa (Koch), Evidently this corresponds to the Sangamon interglacial stage, Core Al172-6 alone is long enough to penetrate the Sangamon and enter a lower zone of cool-water species equivalent to the Illinoian glacial stage, Figures 4-A and B and 5-A and B show the correlation of the climatic curves as well as the correlation by coiling direction of Globoro- talia truncatulinoides, The four cores, Al180-72, A180-73, A180-74, A180-76, are taken near the equator about half way between Africa and South America, The ‘i pilato: bost sola ol 2 2 bosbienne nes arattaisoaeet \ sve bles an ee et e102 oil to id pe ‘est? d witeone: me on onsddiead ohne oa 4 wet assy ait 2 nie ve Spel 8 reve? heuied we a C etait te sonabive wove bate wittel Us volliabasata) evn bana 2 be ‘ tone mewn 6 han odat oe iy we Der oko tat noisicngatl & ies sibs pean sttstnsndotD io moaned on ye peer $4 | 00 ogee sbavtgesint aomepas 2 alt ot ob monet te oiely eins ew * ots bate alyangs 82 os ghettos Qt Aaah mite! ef cnode e oye havnt, sskoaidig watt as trslovings gokoaqe Tatoo Loos ws tl to anaes ods sate, a bie An’ bra B bare At sonigt'D | sane ene atittion i Gnidahstto9 veh ee itow ea sowed ta ve RO RCo RE Inte as iH | obingélus adit oe aroun era0eta. ET+OBEA ll doata: peUKD gek ott oe motnoms me bind oie meeinied: germ wet sents ba ond * Fig. 3 Core Al72-6 (14°59'N, 68°51'W; Depth 4160 m or 2275 fms) Warm Cold Warm Cold Top 20.9°C 21, 6° 1 meter 2 b—>| 14, 6° 3 9.3 4 P < The climatic curve based on the pro- portion of the number of warm-water to cold-water foraminifera is checked with 4 paleotemperature determinations by the oxygen isotope method. 5 5. 50 "Terrien ee vi eating eA 6 tr o- @- -O-8~0- 9-6-4. 5, ° ee eee ae a ‘ % f i bi + + z - 6 t © ! x t aah dite i Seeiientiieticientetiieesae te > cilia 9 si tbr: Ct Cold -@-— 0-9— 7 o~ ~o-@ C) eo O_5 9 -0-e-8— © —O_«¢ | | | ©-8-9-0-0-@_9- — =_ o~» SS @-9-8—@- 0 -0e-6-°-0o_ AQ ~~ e y+ 4. 90 A180-72 00°35 1/2'N, 21° 47'wW A180-73 00°10'N - 23°00!'w 3749 m ~- 2050 fms 3841 m - 2100 fms Correlation by climatic curves Left Right 100% 100% Top—————-—— a, | ' | ! 1 meter | | ! | / | | ‘ ® oO» g — \e ge —s-—e 9 4180-72 00°35 1/2'*N, 21°47*W 3841 m - 2100 fms | i ig | : ie A180-73 00°10!N, 23°00'W 3749 m - 2050 fms Correlation by coiling direction er als | o. Globorotalia truncatulincides ee eee eee LLCS) vik P bi el y ; 1e Vey ANT) Aa | Fig. 5-A Warm Cold Warm Cold Top 6 Top. XN Oi ~o \ ° \ ° | ° b é | 1 i 1 meter \ mete é 4 ° | . r) \ » 2 ° t si » 2 « 2 6 ! ° 1 r j cs] j 2 \ 6 \ . 1) A e 3 t) 3 / é | ‘i ° ‘ 9 d, ‘ 4 4 4 AN ga / a t Ai80..76 4 00940'S, 22 G2!w vs 3E1Z m - 192) fms * L p 4. 80 A 180-74 00°03'S, 24710'w 3329 m - 1820 fms Correlation by climatic curves Right Left Right 100% 100% 100% = asin Ss . I~. — a2 > —6: i iO _— 9— \ Ww ee =p 2. eek: te yti oitiaios elt borptincs yileh eetoo ¢ ob Gavel eotetategmet fT A eogetdaroee icles a auobeint nit ni jasenrel Betsege ons crest horeiiak sermttas an | : vd aneticcicneast ‘odmtin ' eobiis bas € {a0 ow 8960 anny Ye dyson ett 4 on ‘ fe 8 rs f hy ks $ 6 0, « ees on or. 7) ‘ a g 5 : Soa che Fay eee Santa dag Tenth, aes | we enable no} 93 Baan haietosinnt 2:89’ te sigue eit vk Withciy jan ob Hatter Gate conte vovlincind fh eaves niabstas to emipaytiiicn wat « om vies on a reat avid tei edaninay 3H fe: a ‘Guwhaota duildatua of ated biwoste tan + Se! Bye aaa eRe 2) OOo a stodouk onnit at ey Alle Althoneth oo {ess cogs | otto dretas a ala wail" i ies ane i brateste 25. and analysis of four dredge samples off the coast of Africa, The purpose of the study was to gain knowledge of the conditions and processes in- volved in the formation of petroleum deposits, Ina letter to Mr. Bi C. Heezen, Dr. Smith came to the following generalizations: 1, The continental shelf sample had more carbonate carbon and less organic carbon than any of the three slope samples, 2. The amount of extractable organic matter increased with in- creasing water depth, 3. The percentage of hydrocarbons in the extracted organic matter decreased with increasing water depth, 4, As a consequence, the total hydrocarbon content of each of the four samples is just about the same, 5. Paraffin-naphthene and aromatic hydrocarbons were present in all four samples, Chemical and spectographic analyses. A complete series of chemical and spectographic analyses has been made by Dr. G, E,. Hutch- inson, Yale University, on samples from three cores taken in the western part of the Atlantic Ocean, Some of the results have been submitted to the Committee on the Chemical Composition of Sediments. About 40 samples from different cores were sent to Dr, W, W. Moorehouse, University of Toronto, On these samples Mr. Bradshaw has . made spectographic determinations of nickel, chromium, cobalt, vanad- ium and boron. California Research Corporation is making a spectographic » yeeineoanrity oi lhe. cntiniieinnith Instn in ng 6 gt iw ‘wth om fires ot ow aren aren eens samen Oe suet eben shades earns at foal aid pat E " 26, analysis, with special emphasis on titanium, on the top samples from about 350 cores, Quarters of 56 cores from the Gulf of Mexico are being studied in detail at the Field Research Laboratories, Magnolia Petrolaum Com- pany, Dallas, Texas, OH ir) Non ‘ Poy 27. PHYSICAL MEASUREMENTS Mechanical analyses, Numerous mechanical analyses have been made with the aim of obtaining more exact information on the grain size distribution of the sediments, These analyses have given more informa- tion on the graded nature of the deep-sea sands deposited by turbidity currents, The plans are to make more mechanical analyses, Furthermore, 34 samples of silt and sand are being analyzed by Dr. Wilbur Valentine, Brooklyn College, Density measurements, Density measurements of 65 samples taken from 1] different cores have been made, In spite of the fact that the densities changed at different depths of the cores and from core to core there was no sign of a distinct relationship between location, depths, and lithological composition of these cores, In order to give an idea of the density of the sediments in ques- tion it is mentioned here only the highest value of 2, 14 at 130 cm, (dark gray lutite) in a core from 1280 m, (700 fms.) depth, and the lowest value 1, 32 at the top of a core (brownish lutite with worm burrows and foram- inifera) from 4700 m, (2570 fms.) depth, It seems possible that if more samples were measured several relationships could be detected, Sound velocity measurements. In order to find out if the sound velocity through cores could be determined with an ultrasonic pulser 5 tests have recently been made. The velocity determinations were made by the section of seismology at the Lamont Geological Observatory on the basis of the core analyses made at the core laboratory, These are the . toad oxndl sneqiona Leilewbise ereamennntely, al, esie ebete of? ab aoktnnespind: Pees. once. arnt Hie rae hen n ioe sams i ei us oven newty eee dnaylane. seat: atinoenitnae odin de aia | | yaitiiend yd boligegoh. ebnne Way vals okt he swrearhenn bobarg. va ot a8 pia icia et re ‘tee et OTR. santa ont ve: bowled vetoed ate it bene hae, ie te galqmage. i proms webyesne tat. Fe: & treamat mae ne yiiewalt, penacous “bod ll ol eres ‘tess. tent: orf to. ation ak eho, ceed, ave eae. tens od efsereh mn ae tree dm, kewgannl csi f eens oF ote paar bra. aotee Gl ty. ee ee eeutaee oa Sap Poe ae piehted: oh ueiaath 2. be sats ont on “eee, aeee? ho noidheoges re onunp nt Aen ce Ya. yiheeeb, ath it pak ae. owty ae: inbeue, ee a AteES oftio GEE ts. bt & te, evtes tacteit et, vine: ered, banetiase ute ent eewel ond bay. chek, (poe OE ee SL eee) qe. Gat (oatterdk, qtiato: bes awossyd: gone. ire ote, detmesd) ones 626 gok amt tae dasceh, Ceanit OTLEE or, OOTP comeh laartosataty — eqition Rewne. adit bi tee Ratt ot akeun ae ‘dcemaionn een ae beri iereves beseecer, ueew, eelqeies, enor tb belt ehticend aoone # teeters oieeertin es ify. hoeskan as wh Blea aortme davon Shnka ation eeekiars oh winotas Ay yelnm eaod yiameons, overt .” 28, data from the testing; The velocity through brown, slightly muddy, fine quartz sand from a depth of 2840 fms, (5190 m.) was 5400 ft/sec, (1650 m/sec. ), One core section from 350 fms, (600 m,) contains green medium sand, slightly muddy, poorly sorted, with shells of foraminifera and other calcareous debris making up about half of the sediment, the remain- der and finer fraction being mostly quartz; through this type of sediment the velocity was 5300 ft/sec, (1615 m/sec.), The velocity through gray,rather muddy, poorly sorted, very fine sand, mostly quartz, was 5250 ft/sec. (1600 m/sec. ); the core was from a depth of 735 fms, (1435 m.). Through light chocolate brown lutite, very uniform, with a med- ian particle diameter of 1 1/2 microns from a depth of 2900 fms. (5310 m,) the velocity of sound was 4920 ft/sec. (1500 m/sec.). The last core section which was tested contained uniform dark gray lutite. This sediment has a larger calcium carbonate content and greater median particle diameter than the chocolate brown lutite (also called "red clay") mentioned above, The density of this core section was 1,31, and water content: 57% by weight and 74, 8% by volume, The core was from a depth of 2610 fms, (4700 m.). The velocity of sound through this last tested core section was 4670 ft/sec, (1425 m/sec.) The frequency of the ultrasonic pulses was about 65, 000-200, 000 cps. The accuracy of these preliminary measurements is about 5%, The data are important for the understanding of the transmission and reflection of sound, Perhaps these sound velocities are also typical . bas oration ie tio 2 tt bovnee vison xb =a donee ‘ibang ath ate ai! ae awit anon soa eace aw eter = “eitey jhowtas witoe af Neate roillanyorg ‘As poered waleaisy od ee gee 4 cf does les anes won Wah vse puis wstteup stisoan sbaan ) aa PER) a oe ? te. arya & en > oBeere 2 hw r middie row steel wood gsbebowode t aba dguond? doe C22R) ceo 0908 Ya Ateeb a mio emovaing S\4 2 he gogensatb sisting, Ae aft — seo 0603 200 Sao % wate 4 | Mews eectliny bomkedines fede a3 any abate ww sitoos ais twat ad's : Bea tcieta sesmedens scntales vogeel « ant + sanenibes ous wsitol h ik) stud wrod oteleosds ad aud) eo pant aA of snag oe ‘toc . wrnads ane wenohey ya UE OT tro tighew ye OTe - Sates vedaw baw Mt, ayon 6 Heres Be whioet oe ext wi ‘, att eli yond bitte % inwicanin wh may i om a0 808-000 a seeds quay ne | lle ahd to cia ne it taode ane satiate easniechlon smaatt “ hacinitann ott _ aigeiosanst site voit 2 vets said a saree es spt owe 29. of a specific stratigraphical interval, The plans are that an ultrasonic pulser will be installed on the research vessel which belongs to the Observatory and the velocity of sound should be measured through all the cores that are obtained, | |" {benbedde ot Sadt unos odd Its & 30. PETROGRA PHY Clay minerals, The clay mineralogy of three cores ds being stucied by Dr, Maurice C, Powers, the Johns Hopkins University, Bal- timore, Top and bottom samples of two of the cores (location: 37°01 1/2! N. 74°27 3/4'W and 36°08'N, 68°55'W) have been analyzed, Ina letter to the laboratory Dr, Powers came to the following conclusions: "All of the samples contain the same type and amount of clay minerals, There may be just a slight trace of kaolinite present, but the dominant minerals are an illite and a chlorite-like material, The chlor- ite-like mineral may be forming from a montmorillonoid or a degraded illite or chlorite. I have been able to definitely establish that the chlorite- like mineral becomes stable to higher temperatures as distance from shore is increased, The increase in thermal stability with distance from shore is almost certainly due to a more perfect organization and growth of the chlorite crystal, I may summarize by saying that the sample con- sists of clay-size quartz particles (less than 10%), illite (about 30%), and a "swelling" chlorite mineral (60%),." A series of photographs of samples from nine cores has been made at the Electron Microscope Laboratory, Columbia University. Mr, Abdullah Sayyeb of the Department of Geology, Indiana Uni- versity, is studying a series of samples from five cores by means of com- plete mineralogical analyses of the clays and sands, Series of samples from six cores are being studied by Mr, M, N, Hill, Department of Geodesy and Geophysics, Cambridge University, Eng- land, He is investigating the physical properties of deep sea clays, 31, Volcanic ash zones, A series of samples of volcanic material from deep sea cores is being studied by Professor Erik Norin, Mineral- ogiska Institutet, Uppsala, Sweden, Meteoritic dust, About 50 meteoritic spherules have been found in the cores, Several were studied by Dr, J. D. Buddhue, Institute of Meteoritics, University of New Mexico, These have been described in the monograph ''Meteoritic Dust", J, D, Buddhue, The University of New Mexico Press, 1950, Rocks. A collection of several hundredweights of boulders dredged from depths approaching 4575 m, over the Mid-Atlantic Ridge has been analyzed by Dr. S, J, Shand, Columbia University. Some of these boulders are of limestone and the large proportion consists of eruptive rocks referable to the groups holocrystalline gabbroic rocks, basalts (pillow lavas) with and without olivine, and serpentines, The knowledge of composition of the Mid-Atlantic Ridge has been derived hitherto from the islands and island groups which are scattered at long intervals along its course, On these islands the dominant rock is basalt, According to? Dr. Shand the collection confirms the predominance of basalt and makes at least two notable additions to the record, namely an abundance of serpentine and a mylonitized gabbro. (For detailed descrip- tion and analyses see ''Rocks of the Mid-Atlantic Ridge" by S. J. Shand, Jour, Geol. vol, 57, pp. 89-92, 1949; and ''Age of a Mid-Atlantic Ridge Basalt Boulder", D, R, Carr and J. L. Kulp, Geol, Soc. Am, Bull., vol, 64, pp. 253-254, 1953.) ite oie atau ‘. j ne aed sian pabiwaiis alles seston 68 Sods tity oltitenota: bis astride wis Sniiot we HE A aw “ee YPN y GHEE Ghar asewys y “thd Nestea Cl ovod eeedl! oan dell to vitiinowia® 0 yoo Ho Re Geri att ae & a Peal skies oat dager ee mies ce anand whan ie stalliuad’ Eo elhne dis ho wedtyaoo & vege : eR RS ushsaibldis arisqab eet WERRTE se el es Phemest searwiet? adowies Grae wa el vd Boones as ’ Ie eine eciinieiy ee) cal Nae amend! Yo otis siohieod sone greoteleey- weet: Ce | waded epee “ibd OH obdingia hort ailoon » y hh eT eoutineos ee pie cai ee pie bie mlbw (navies wottig) poeieas: od Bak oQhh CBE A to lglg to oghe need Je bkawiion. seawdi ener hele? bee whanke aes coed ob Wh obec ies Hoax venedinat std uanesit asad O° "Sexes ett yaols when : . "MOND eins ait ong old “a eee WOES OTES Od imede orl + wit gent | fame kevgasy ot ‘oe eile Waele ‘eblton tome visi a asia hea 3 ad nee bulla h 4 de cady, we win Bet ia hia ibdelbesiseboile ‘Pan HE Ryd ghee Saath DA ody ord WALOR” oae rowebens sind ogbill obteairh Mbiiid: Oba eae hae oes ate vty re ‘alia ‘woot 326 Dr, H. H, Hess, Princeton University, has analyzed "black sand" leached out of limestone which was obtained in cores from south of Bermuda. Ina letter to the laboratory Dr, Hess describes it as '' Perov- skite, Fi-garnet (melanite), black magnetic opaque material probably titaniferous magnetite and nearly opaque rounded grains of deep red brown color which probably are rutile," From the 200 fms, (366 m,) seamount east of the Atlantis Sea- mount (34°08! Ny, 30° 14! W) there was dredged about half a ton of flat calcareous rocks composed primarily of foraminifera, pteropods and bryozoa, The rocks are quite well cemented and appear on underwater photographs to be eroded, rounded fragments of the formation which un- doubtedly underlies the truncated top of the mount, At present the temper- ature at the surface in this area is about 22°C and the temperature near 200 fathoms is about 12° C, Dr, C. Emiliani, the University of Chicago, has made paleotem- perature determinations by the oxygen isotope method on a sample of these rocks, The benthonic foraminifera gave a temperature of 16, 840.5°C, A radiocarbon «cy age determination was made on a sample of the rocks by Dr. J, L. Kulp, Lamont Geological Observatory. It was found to be 12, 000+900 years, The age of the rock, 12,0004900 years according to Kulp, agrees reasonably well with that of the Two Creeks or Allergd phase, which Libby! found to have an average age of 11,400+4350 years, At that time 1, Willard F, Libby, Radiocarbon Dating, U. of Chicago Press, 1952, Pe 88, 2 Te a ‘ hs eee Pie AC ‘ m0 On ro eS Re cae eu a ¥ Dae ate Hin PANS ae Ny te KOU, Be ecilr m1 5 te + any, si SH was SING. PAS ‘ Eee 33, of warmer climate sea level ought to have been somewhat higher than it became shortly afterward when the ice sheets re-advanced, Such a lower- ing of sea level following deposition could very well account for the cemen- tation of the rock and subsequent fragmentation by surf, The temperature, 16, 8°, offers no serious objection to this interpretation, Final ui oy ey _ phanianba owe ssonda age 34, PUBLICATIONS Ericson, D,B., M, Ewing and B, C, Heezen, Deep-sea sands and;sub- marine canyons, Bulletin of the Geological Society of America, vol. 62, pp. 961-965, 1951. Ericson, D, B., M, Ewing and B, C, Heezen, Turbidity currents and sediments in North Atlantic, Bulletin of the American Associa- tion of Petroleum Geologists, vol, 36, pp. 489-511, 1952, Ericson, D. B., North Atlantic deep-sea sediments and submarine can- yons, Transactions of the New York Academy of Sciences, pp. 50-53, Dec., 1952, Kulp, J. L., H. L, Volchok, H, D. Holland and D, B,. Ericson, Thick source alpha activity of North Atlantic cores, Journal of Marine Research, XI, pp. 19-27, 1952, Ewing, M., B. C, Heezen, D. B. Ericson, J. Northrop and J, Dorman, Exploration of the Northwest Atlantic mid-ocean canyon, Bulletin of the Geological Society of America, vol, 64, pp. 865-868, July 1953, Ericson, D, B,, Deep-sea cores and currents in the Pleistocene North Atlantic; will be delivered at the meeting of the Geological Society of America, November 10, 1953, Ericson, D, B,, B. C. Heezen and M, Ewing, Further evidence for tur- bidity currents from the 1929 Grand Banks earthquake; will be presented by Ericson at the meeting of American Association for the Advancement of Science in Boston, December 30, 1953, Ericson, D, B., Correlation by coiling direction of Globorotalia trunca- tulinoides; submitted for publication. MENT PA fal , ONT ANTE, | Me edun Has ebrae son-qnot eee ol) att hina jualin Me ee oi teaih bo Yisisot Laatpodast onto aera convene mere bua steoriws yithidawT etowooHt 60 ‘ye des ale iM at n -GiooeaA asotroms off fy eitoline wohhead) & dacolt ad. stasmbow fee shL2-286 yg ek tow sau haha it mimetorre’ Yo cate ene omitenidiva brs edonihien qem- nent alten hn doh (ll a iq eoutstse ho eshaniaitn due veil sult to ameent enog, Avid’ .aonsiss A 0 boo Haoiloht a \doeloto¥ ot Pe av} . stineM Yo Isaxwel, vote abhanlid dieolt to tl Psegr aoTOR See aed dX dowaseat puree ok Bers qondinol ot pene Pang s200H 2 rae Sitelina roves ne9o0-biar otaeltA tapwiliaelt edd Yo (888+308 .cg hd dow .waltsecA to pole lasigetosd uit bo | ditto saocoteintt edt ak eimwnte> bee oytos aee-goad ee a ne ytsise? Lasinotoo® sft la paitvont ont de hesevited od Miw ;phaehh tte! 01 sadwevelt ‘ahivadennsiaaliait | <4ut 70) sonebive rodire% .goiwa \M bre moneol .D 2 ,.4 2 een 6d tive jotsupdixas edned haor O56! ott? cen atnorgns yabht tat molainoscA eevitomA lo paitesm oft te qoenked yt batneestq | | 201 ,0€ rodmoved wrotadd a eonel We tnomapenrbA ott aii ; ogoagst sileiotodolD to aoltoutih yuiltes a sndtnbeleiaty a Mt oe e sookia vida x0 botahendne cw ghbemihest ae