i ECESSION OF THE LAST HEET IN NEW ENGLAND ERNST ANTEVS xe N GEOGRAPHICAL. SOCIETY EARCH SERIES NO. IT on ar LAST ICE RECESSION IN NEW ENGLAND AMERICAN GEOGRAPHICAL SOCIETY RESEARCH SERIES NO. II W.L. G. Joerc, Editor THE RECESSION OF THE LAST ICE SHEET IN NEW ENGLAND BY ERNST ANTEVS University of Stockholm WITH A PREFACE AND CONTRIBUTIONS BY J. W. GOLDTHWAIT AMERICAN GEOGRAPHICAL SOCIETY BROADWAY AT IS6TH STREET NEW YORK if (opto) ea) COPYRIGHT, 1922 es THE AMERICAN GEOGRAPHICAL SOCIETY - OF NEW YORK THE CONDE NAST PRESS GREENWICH, CONN. Tig: oOfe LATE mo, Il CONTENTS CHAPTER PREFACE, BY J. W. GOLDTHWAIT INTRODUCTION I VARVE CLAY, AND THE METHOD OF INVESTIGATION II CoNDITIONS IN NEW ENGLAND DURING THE DEPOSI- TION OF THE VARVE CLAY III] DESCRIPTION OF THE SECTIONS AT THE LOCALITIES SEUDIED . IV THe NorMAL CuRVE V THE CONNECTIONS VI ABNORMAL VARVES, AND DISTURBANCES IN THE CLAY VII THe RATE OF RECESSION AND CONDITIONS CON- TROLLING RECESSION VIII THe CiimaTE DuRING THE RECESSION, AND CLI- MATIC PERIODICITY IX THE BEARING OF THESE STUDIES ON PREVIOUS WORK AND ON NEW PROBLEMS EXPLANATION OF THE MAP ILLUSTRATING THE RE- CESSION OF THE LAst ICE SHEET FROM NEw ENG- LAND AND NEw YorK, BY J. W. GOLDTHWAIT . List OF REFERENCES INDEX PAGE 74 89 94 104 108 117 FIG. Pw: LIST OF ILLUSTRATIONS Manner of deposition of varve clay . An exposure of varve clay 3:9. 2000/0.) ).) facing View showing the method of measuring the clay IE HESCS) See OI Came A ON UW AMR O a SANUS NA Na dseay again eon OYes Sample of measurement made in the field and curve constructed from it in the office Maps showing the position of the localities examined in the Connecticut Valley. Scale, 1:160,000 Map showing the position of the localities examined in the Merrimac Valley. Scale, 1:160,000 Curves showing three drainages of ice-ponded lakes into the Connecticut River above the Passumpsic Section at locality 24, southeast of Amherst, Mass. Part of curves at localities 19 and 20, Northampton, Mass. Annual rate of ice retreat in southern Finland, after Sauramo Curve showing drainage during years 5671-5676 recorded at locality a, Catskill, N. Y. i ‘ Part of curves at localities 27 and 28 near enna Mass. . PLATES I-V [Normal curve, covering 4,400 years in 21 sections, VI recording the recession of the edge of the last ice sheet from Hartford, Conn., to St. Johnsbury, Vt. (At bot- tom of Pl. V, curves I-III, three groups of individual curves illustrating connections and correspondences Wwichin each group) ea ee a Aeend Map Illustrating the Recession of the Last Ice Sheet from New England and New York, compiled by J. W. Goldthwait. Scale, 1: 1,250,000 . . . . . 1,000 <100 feet 24 with bottom 31 km. <2F iis 7 to 28 35.8 miles = 189,024 feet | About 1,630 116 feet None with bottom | 57.6 km. 35 m. 24 to 28 16.8 miles = 88,704 feet About 270 328 feet 27,5 km: 100 m. 28 to 29 12.8 miles = 67,584 feet About 350 193 feet None with bottom | 20.8 km. 59 m. 29 to 31 12.4miles = 65,472 feet About 275 238 feet None with bottom | 20.1 km. Gi2\ sole 31 to 40 19.5 miles = 102,960 feet >300 <343 feet 40 with bottom 31.4 km. 220 feet Depth to bottom | 11.6 km. 67) Ml at 60 unknown TIME OF RE- RATE OF 76 ICE RECESSION IN NEW ENGLAND TABLE I—RATE OF RETREAT OF THE ICE BORDER—Continued TIME OF RE-|} RATE OF LOCALITIES DISTANCE TREAT IN |RETREAT A YEARS YEAR 61 to 64 15.5 miles = 81,840 feet 133 615 feet Both with bottom | 25 km. 188 m. 64 to 67 A4Amiles = 21,120 feet <26 >812 feet 67 practically with | 6.4 km. >246 m. bottom 67 to 70 21 miles = 110,880 feet >141 <786 feet Both practically 33-8 km. <240 m. with bottom 70 to 71 14 mile = 2,640 feet 3 880 feet 71 with bottom 0.8 km. 268 m., 70 to 75 6 miles = 31,680 feet 29 1092 feet 75 with bottom 9.7 km. 333 m. 75 to 79 5 miles = 26,400 feet 24 1100 feet Both with bottom 8 km. 335 m. 79 to 86 Irmiles = 58,080 feet About 70 830 feet 86 practically with | 17.7 km. 253 m. bottom RATE OF RECESSION IN THE SOUTHERN ZONE In the southernmost zone, between Hartford and Springfield, the recession was consequently rather fast, amounting to about 243 feet (74 m.) a year. In Massachusetts the rate decreased considerably, averaging between Springfield and Greenfield only 116 feet (35 m.) annually. The recession, however, seems to have varied greatly in speed in different zones and even to have been interrupted by readvances. Between localities 7 and 24 the retreat was less than I00 feet (31 m.:) a year. RATE OF RECESSION 77 PROBABLE OSCILLATIONS OF THE ICE BORDER IN THE AMHERST-NORTHAMPTON REGION In November, 1921, there was, at locality 24, southeast of Amherst, an excellent long vertical section, part of which is shown in Figure 15. The sequence of strata is clear on the left side of the section. The thicknesses are as follows, beginning at the top: 2)4 feet till. 2% feet crumpled clay, about 150 varves. 10 feet excellent clay, varves 4450-4668. 1% feet till. More than 1% feet quicksand. To the right, the whole clay bed is crumbled down to the till. The pressure which folded the clay seems to have come from the west-northwest. The connection between the covering till and the folding of the clay is evident, but the circumstances under which the till was deposited are not clear. Those small rin M4 SO PFE Pp Pp PRE ONE YS SY SUG END UY MY ELIE EVES NY ES TASS BSN NEES US PES IVES BAYES) TONG VSN DREN ESE PRL VUES INGTON, Fic. 15—Section at locality 24, southeast of Amherst, Mass., showing till on top of the varve clay and partial folding of the clay by pressure from the west-northwest. ICE RECESSION IN NEW ENGLAND 8 I™~ “sSOUMOIY) [eNJOe £¢ ‘aleIG oz AjI[eIO] ye SOAICA OY} JO SSOUYIIY} Ul oSvorUT [Roo] oy} BSurmoys “ssepy ‘uUoPdureyVION ‘oz pue OF SalpIPeIo] Je Sa9AIND JO JIeG—9I “Ol (We >7*" 18cm) NAIA | Ay 9" (23cm) Mh RATE OF RECESSION 70 icebergs which were broken off in the glacial lake can hardly have been able to push together a clay bed so thick. That a landslide was the cause is equally improbable, since the ground towards the west rises only 60 feet in the first half-mile, where it reaches the foot of a drumlin whose crest is only 140 feet above the local- ity. The last possible explanation, that the ice edge readvanced, pushed together the clay, and deposited the till cover, also meets some difficulty. The readvance would have occurred about year 4800, i.e. at a time when deposition of clay proceeded undis- turbed at Northampton, 7 miles to the west. Since locality 28, the ice edge at which lay 16.8 miles (27.1 km.) north of the ice edge when at locality 24, was uncovered by the ice before year 5084, the annual recession of the ice from 24 to 28 must have averaged about 328 feet (100 m.). This fact, however, forms no obstacle. Within less than 220 years after the halt at Clare- mont, N. H., the annual recession amounted to 615 feet (188 m.; see p. 76), and in Finland Sauramo (1918, p. 31) found that the rate of retreat was most rapid just after a halt or a slow recession. At locality 20, situated at the northwestern edge cf Northamp- ton, the following section was measured, beginning at the top: 3 feet sand. 2 feet weathered and disturbed varve clay. 1% feet clay, I10 varves, not connected with the normal curve. 13 feet silty clay, homogeneous through disturbance. 4 feet quicksand, slidden at the top, varves 4633 and 4634. Silty clay, sandy at the top, varves 4377-4632. Depth to bottom unknown. Figure 16 shows in one-third actual thickness varves 4560-4634 at this locality and, for the sake of comparison, varves 4560-4642 at locality 19, situated 1% miles to the south. The most interest- ing thing about profile 20 is the increase in thickness of the varves beginning with number 4586. Varve 4587 and those from 4592 upward consist of quicksand. Below number 4586 the layers have about the same thickness as at the other localities in the region but consist of somewhat coarser material. The 80 ICE RECESSION IN NEW ENGLAND greater thickness of the varves can hardly be due to decreasing depth because of sedimentation at the locality, since this lies about 125 feet below the level cf the glacial lake, and since the varves are exceptionally well developed. Shallow-water varves have heterogeneous material and thin and indistinct winter layers, as well as wavy surfaces. Nor is it likely that the reason is drainage, because this ought to have been felt over a large part of the lake, if not over the whole of it. The fact can hardly have been caused by a shorter distance from the locality to the mouth of the eventual Mill River of that time, since this would have discharged into a bay three miles northwest of it, i.e. as far away from here as from localities 19 and 21. So it seems most probable that the zone indicates an approach of the ice border which during year 4635 or somewhat later overrode the clay, crumpling up its upper part. It would have been a local tongue, extending from the northwest, since deposition of clay proceeded at other points in the vicinity. If, however, the lake during years 4586 to 4634 did not stand at its highest level (cf. p. 52), it may be possible that the thick varves were due to some of the other possible reasons mentioned as alternatives. North of Northampton, close to my localities 21 and 22, Emerson (1898, p. 686, and Pl. 18, Fig. 3) in 1880 found in a long railway cut, in the midst of alternating till and sand beds, contorted varve clay. The overlying till was no doubt deposited by the land ice during a marked oscillation of its border. The unusually complete disturbances of the clay at localities 21 and 22 also make it probable that they once or several times were overlapped by the ice. To sum up, there are in the Northampton-Amherst zone different facts which seem to indicate oscillations of the ice edge. If the conditions are correctly explained, the ice border returned to locality 20 during year 4635 or somewhat later, after having left it more than 258 years earlier; it returned to locality 24 about year 4800, or some 350 years after it first left; and to localities 21 and 22 at some other date not known. Furthermore, the RATE OF RECESSION 81 rate of the final ice retreat between localities 24 and 28 amounted to 328 feet (100 m.) a year. Further investigations are needed to reveal the actual conditions. RATE OF RECESSION IN THE MIDDLE ZONE In northern Massachusetts the amount of the annual recession was 193 feet (59 m.). The rate of retreat increased until the ice edge reached the Bellows Falls region, whereupon it decreased again, judging from the halt of the ice edge at Claremont and from results obtained in the Merrimac Valley. When fastest, the recession reached approximately 370 feet (113 m.) a year. In the Merrimac Valley the retreat was a little slower than in the Connecticut, probably because it was situated closer to the sea, where the sky was more clouded. The highest rate was reached a little north of Concord. The subsequent retardation was rather noticeable. OSCILLATIONS IN THE LAKE WINNEPESAUKEE REGION In the Claremont-Lake Winnepesaukee zone the ice edge again halted and readvanced. At locality 41, in the Connecticut Valley, four feet of coarse gravel with several boulders a foot in diameter overlie discordantly a thick deposit of varve sand which represents more than 50 years (see p. 22). The gravel is, no doubt, outwash deposited during a readvance of the ice edge. Around Lake Winnepesaukee till in doubtless its original position frequently overlies varve clay, marking oscillations of the ice border (Upham, 1878, p. 131). A few such localities were visited by Goldthwait and the writer. At Clay Point, 3 miles southwest of Wolfeboro, at the southeastern end of the lake, the varve clay, which according to Upham is at least 15 feet thick, is now covered by talus. The original position of the overlying till is obvious. At Weirs, on the western side of the lake, a third of a mile north of the railroad station, a 30 to 40-foot 82 ICE RECESSION IN NEW ENGLAND section at the bottom of a hill shows the following layers, beginning at the top: 2 feet till, mostly blocks. 4-8 feet silty and sandy disturbed clay. Varves 1% to 4 inches (1 to to cm.) thick. Varve limits difficult to distinguish. 3—4 feet stratified sand. 14-3 feet disturbed varve clay. Thick varve clay with several disturbed zones and here and there morainic material. The clay consists of sand or silt and of thick, greasy clay layers, but the varve limits, in many cases, cannot be determined. At the bottom of the section the varves are sandy and 6 to 8 inches (15 to 20 cm.) thick, probably indicating inconsiderable depth to the base of the deposit. The covering till may have been deposited by the land ice, judging from Upham’s statement that on the top of the hill, the sides of which show till at the surface, a well 27 feet deep encountered only varve clay. The consistency of the clay seems also to show that it was deposited off a practically stationary ice edge. The sand bed may mark a readvance almost to the spot. After a short renewed retreat the ice overrode the clay and deposited the till cover. This halt is not registered in the normal curve, because I did not succeed in getting varve series so long that they bridged it and could be connected with profiles north of the zone. In the Connecticut Valley the Bellows Falls lake was filled up with sediments probably about 300 years before the ice uncovered localities 61 to 63 north of the zone of retardation. Not even localities 41 and 43 can be connected with those south of them. Nor is the halt recorded in the Merrimac Valley. The lake at Concord also was filled up with sediments too early, though certainly 75 years later than the Bellows Falls lake. As the ice retired and began to uncover the outlet of the Winnepesaukee basin, the drainage area, tributary to the Merrimac, became very large, and the volume of water passing through very considerable. The increase of the current was followed by increase of the critical depth of clay sedimentation in the course of the current. At points swept by the current sand was deposited RATE OF RECESSION 83 even in deep water, and so the varves at closely situated localities in the middle of the lake sometimes differ greatly in thickness. At locality 52 deposition of sand started during year 6232 at a water depth of about 75 feet, and at locality 57 during year 6308 at a depth of about 100 feet. After the critical depth of clay sedimentation had been reached at a given point the lake there was filled up with sand and silt in a few decades (cf. pp. 25-28). My attempts to bridge the gap in the Hudson and Mo- hawk Valleys were also without result, in the former because the clays did not offer any exposures and in the latter on account of the general absence of clays. How many varves are lacking in the normal curve cannot, of course, be stated, but their number in view of the facts known seems to amount to 200 or 300. If this estimate is correct, the retardation and the readvance should represent at least 400 years. RATE OF RECESSION IN NORTHERN ZONE As soon as the recession from this line had started it seems to have become quite rapid, since between localities 61 and 64, i.e. during the first 100 or 200 years, it averaged 615 feet (188 m.) a year. Between White River and Hanover it reached over 812 feet (246 m.). After a slight decrease it increased again and reached, between localities 75 and 79, 1,100 feet (335 m.) a year, the fastest rate observed in New England. Then the speed diminished again, amounting, between localities 79 and 86, to about 830 feet (253 m.) a year. When the ice edge had retired beyond St. Johnsbury it probably halted and readvanced. Since I hope to be able soon to collect more material regarding the conditions in this region, at this time it may merely be stated that the ice border seems to have readvanced to St. Johnsbury in the Passumpsic Valley and to the junction with the Pas- sumpsic in the Connecticut Valley. The final retreat of the ice from locality 85 occurred about 280 years after it uncovered locality 86, a mile to the west. The halt seems to correspond to the one registered by moraines at Bethlehem and Littleton, 84 ICE RECESSION IN NEW ENGLAND 15 miles (24 km.) east of here, which have been mapped by Goldthwait (1916). As for the length of time represented by the halt, 280 years may be a minimum figure. . RATE OF RETREAT AND TYPE OF CLAY Difference in thickness between varves is usually due to varia- tion of the coarse summer layers, the winter layers being almost equally thick from year to year. Accordingly, thin varves con- tain a greater percentage of fine material than do thick ones. The thickness of the varves, the amount of sedimentation, is a measure of the amount of melting. Since slow recession and halt of the ice border, as observed by De Geer long ago, are usually recorded by thinner and more greasy varves than is fast recession, it is evident that the retardations were character- ized by little melting, in other words, by low temperature (cf. p. 86). Thus the clay gives an idea of the rate of the retreat and of the climatic conditions, especially in regions which, like Fenno-Scandia, are built up of hard, coarse Archean rocks (see also Sauramo, 1918, p. 37). This rule, however, can be applied only with the greatest caution to districts occupied by both hard and soft rocks. A soft, fine-grained slate or schist evidently gave rise to a fatter clay than did a hard, coarse-grained granite, regardless of the amount of melting. There occur, therefore, in New England clays deposited during rapid recession consisting exclusively of such fine material that the varve limits cannot be distinguished. Another reason why the thickness and texture of the varves cannot be used as indicators of the ice retreat in New England is the fact that, in the small lakes which occupied the valleys, thick and thin varves often only mean large or small drainage area. It is particularly significant that during an annual reces- sion of more than 1,000 feet (300 m.) comparatively thin and fat clay varves were deposited in the Connecticut Valley at Woodsville, while at locality 63, 50 miles farther from the ice front but below important tributaries, the same varves are silty and three to four times as thick. RATE OF RECESSION 85 When the details of the ice retreat are known, it will be possi- ble to discriminate between peculiarities dependent upon the character of the mother rock and those due to the rate of reces- sion or to the climate. CONDITIONS CONTROLLING RECESSION The factors causing and influencing the disappearance of the ice sheets were many and different: temperature, precipitation in form of snow and in form of warm rains, topographic condi- tions, conditions favoring discharge of icebergs, etc. The ice itself moved forward, and the retreat of the ice edge was the excess of the melting over the advance. The combinations of the factors were complicated and changing, and so in many cases they cannot yet be analyzed; but detailed and exact chronological studies promise to shed light upon these funda- mental questions. TEMPERATURE The importance of the summer temperature is probably best shown by De Geer’s studies in Sweden (1912, 1912a, 1914). The most significant evidence is perhaps the great difference in the rate of the recession of the ice on the Swedish west coast and that in the Baltic region. In western Sweden the ice edge stood practically still for one or two thousand years, while it receded at great speed in the eastern part of the country. De Geer’s explanation is that on the west coast the air was very foggy and the temperature low and constant, while in the Baltic region the sky was clear and warm and sunny days were frequent. The intensely dense fog along the Gulf Stream in the Arctic is well known. On Bear Island, halfway between Norway and Spitsbergen, the writer from the beginning of August to the middle of October in 1916 saw the sun in all for but a few hours. The summer temperature on this island is, on the average, a few degrees above the freezing point and exceedingly even. In other Arctic regions, as Spitsbergen, the insolation on bright 86 ICE RECESSION IN NEW ENGLAND days can be very high, causing the glaciers to melt considerably and the rivers to swell strongly (see also Hann, 1911). The nourishment of the ice sheet, which, as Hobbs (1911, p. 287; I911a, 1915) points out, largely occurs in such a way that the snow, fallen during a relative calm, is by violent anticyclonic surface air currents swept from all central portions of the ice sheet and deposited near and about the margins of the ice shield, may perhaps have become greater in western Sweden, but that does not explain the rapid recession in the Baltic region. Nor can the discharge of bergs from the ice front explain the different rate of retreat. In the present Baltic area, as well as in the surrounding lowlands, which were submerged below the Baltic of that time, calving doubtless played an important rdle, particularly where the waters were deep and wide and the lifting power and wave action was great. But since the supply of ice in these regions was greater than in the supramarine parts of eastern Sweden, the recession was almost as fast in these latter. The important part played by sunshine as compared with that of rain is evident, for the Swedish west coast, in late glacial time, had doubtless much more rain than had the Baltic district. Rains in Arctic regions are also usually cold and sparse. Indication of the great importance of temperature seems also to be found in the thicknesses of the varves, which varied greatly from year to year. If the recession had been mainly determined by conditions of precipitation, it is to be expected that the recession and the clay sedimentation should have been prac- tically the same from year to year and should have undergone only slow variation. Variations of temperature seem also usually to be the causes of the long and marked fluctuations in the rate of recession, which themselves, to be sure, can be readily explained by changes in precipitation, since in Sweden and Finland the thicknesses of the varves are found as a rule to stand in good relation to the rate of retreat and the thin varves deposited during halts indi- cate inconsiderable melting (cf. p. 84). RATE OF RECESSION 87 TOPOGRAPHY The influence of topography was important. The direction of ‘striae and the position of recessional moraines indicate the fact, and detailed mapping of the ice front by means of the clays reveal it still better, as researches in Sweden have shown. The rate of flow of the ice was rapid in valleys and basins, while it was checked on highlands. In the marginal zone the distal parts of the valleys were filled with protruding ice lobes, though dis- charging of icebergs counterbalanced their formation. As the ice edge withdrew, the lobes gradually disappeared, and, when the ice front reached the northern, proximal end of the valley, it had become concave. The flow of the ice, though now slower, was yet more rapid than in the higher neighboring parts, but it was more than counterbalanced by calving. PRECIPITATION A valuation of the influence of precipitation, or nourishment of the ice, is particularly difficult, since this had much the same effects as the temperature and may have co-operated with it in the great advances, readvances, and recessions. For certain local readvances of the ice, not due to topographic conditions, precipitation may have played the leading part, since this is likely to show greater differences between near-by regions, topo- graphically similar, than does the temperature. The ice lobes southwest of Lake Superior may be taken as examples. There seems to be one known case of a halt in the retreat in Fenno-Scandia chiefly determined by increased precipitation, namely that at the Inner Salpausselk4 in southern Finland. While the ice edge halted for 183 years at this morainic line (Sauramo, 1918, pp. 35, 38, 43, 44), which in some districts, is divided into a series of moraines, a clay consisting almost ex- clusively of fine material was deposited, as usual during halts. In contradiction to the rule, however, the varves marking the halt are considerably thicker than those deposited during the 88 ICE RECESSION IN NEW ENGLAND previous retreat, which was rather slow. Sauramo does not give an explanation of the case. It seems evident that the lack of coarse material indicates absence of strong currents of the ice water. In other words, there was at no time in the summer rapid melting. Warm sunny days must have been few or none, and the temperature very even. On the other hand, the melting must have lasted for several months, since the sedimentation was great. The fact that the ice edge on the whole did not withdraw under these circumstances seems to prove that the nourishment of the ice was much greater than usual. This is an interesting case of equilibrium between a great supply of ice and considera- ble melting at low temperature. The clay probably does not indicate short summers and long winters, as supposed by Briick- ner (1921, p. 57; cf. our p. 3). CHAPTER VIII THE CLIMATE DURING THE RECESSION, AND CLIMATIC PERIODICITY THE CLIMATE DURING THE DISAPPEARANCE OF THE ICE The climate during the disappearance of the ice in New Eng- land has been touched upon in the preceding pages. Since, as explained there, the summer temperature seems to have been the chief factor in the melting of the ice, the rate of retreat gives an idea of the temperature. And since the rate of recession varied considerably in the different zones (see pp. 74-84), the temperature also may have undergone great fluctuations. The climate was not arctic, for the melting of the ice, in many zones, was quite rapid. Since, however, a vast amount of heat was used in the melting of the ice and heating of the cold ice water, the temperature remained comparatively low in a belt off the ice front. This arctic to subarctic zone shifted northward as the ice front withdrew. It doubtless accommodated an arctic and subarctic fauna and flora, about which, however, very little is yet known. Although relicts of these northern plants and ani- mals still survive on the highest summits in New England, only a few occurrences in the varve clays seem to have been reported. In the varve clay at Northampton, Mass., particularly at my locality 23, Emerson (1898, p. 718) found remains of the following plants: Viola palustris L., Vaccinium oxycoccus L., Vaccinium uliginosum L., Rhododendron lapponicum Wahl., Arctostaphylos alpina Spr., Arctostaphylos uva ursi Spr., Oxyria digyna Campd., Salix cutlerti Tuck., and Lycopodium selago L. Of these, Salix cutlert and Vaccinium oxycoccus are very abundant. The plants indicate an arctic to subarctic climate. They were deposited when the ice border uncovered northernmost Massachusetts. They must have grown in this region or still closer to the ice edge, since any transportation must have been southward. I am 90 ICE RECESSION IN-NEW ENGLAND informed by Mr. R. W. Sayles that in varve clay taken by him at locality 78, about 10 feet above the till, Dr. E. C. Jeffrey found microscopic fragments of coniferous wood. In Sweden the rate of the ice retreat from the south coast of Blekinge (56°N.) to Ragunda (63°N.) in Norrland (450 miles, or 720 km., in 4,000 years) averaged about 600 feet (180 m.) a year (De Geer, 1912, 1915). In the southern part, from Blekinge to the Fenno-Scandian moraines (150 miles, or 240 km., in 2,000 years), the annual recession amounted to 400 feet (120 m.), and in the northern part, from the moraines up to Ragunda (280 miles, or 450 km., in 1,500 years) to 1,000 feet (300 m.). The morainic belt represents two halts and slow intervening recession for together nearly 700 years (Sauramo, 1918, p. 23). In New England, between Hartford, Conn., and St. Johnsbury, Vt. (185 miles, or 298 km., in 4,100 years), a zone lying closer to the periphery of the last ice sheet than does Sweden, the annual recession averaged about 240 feet (75 m.), i. e. less than one-half of that in Sweden. Assuming that during the ice retreat the supply of ice was the same in Sweden and New England and that the rate of recession reflects the temperature to the same extent in both regions, it must have been considerably warmer in Sweden when the ice disappeared there. Accordingly, the knowledge of the late glacial climate in Sweden cannot be directly applied to New England. As far as this is based on the immigra- tion of the flora, it should be noted that this migration occurred on a narrow front across the Danish islands, which from time to time connected Sweden with the continent (Antevs, 1922), while the migration northward in New England occurred on abroad front. In southern Sweden the land uncovered from the vanishing ice was first taken possession of by an arctic to subartic flora with Dryas octopetala as its most typical constituent. Even before the disappearance of this flora, birch (Betula odorata and Betula verrucosa) and pine (Pinus silvestris) were more or -less abun- dant (von Post, 1916). The temperature may have corresponded to that now prevailing in northern Scandinavia (Andersson and Birger, 1912, p. 130). Alder (Alnus glutinosa), elm (Ulmus CLIMATE DURING RECESSION QI montana), linden (Tilia europaea), and hazel (Corylus avellana) immigrated almost immediately after the extinction of the arctic flora and occurred in the whole of southern Sweden in early post-glacial time, that is to say about 2,000 years after the release of the ice (von Post, 1916). At the present time alder and elm occur to beyond the 65th parallel of latitude, and linden and hazel in the coast region up to the 63rd parallel, or central Norrland. In northern Sweden the land was from the beginning occupied by a temperate pine flora, essentially similar to the pre- sent vegetation of the region (von Post, 1911, p.20). Thus the amelioration of the climate, in late glacial time, became more and more noticeable. Towards the end of the epoch the arctic belt, which had previously followed the retiring ice edge, had ceased to exist. THE VARVE STUDIES As A KEy TO CLIMATIC PERIODICITY The clay studies, when they shall have been carried out in detail, will increase our knowledge of climatic periodicity. They furnish perhaps the best material known for the study of long periods and one of the best for that of short ones. Since the disappearance of the ice was due to climatic reasons, the perio- dicity in climate is recorded by the annual amount of ice melting, the rate of recession of the ice edge—recession, halt, and re- advance—and the amount of sedimentation (cf. pp. 85-88). The short periods, that is to say those up to a few decades in length, are best illustrated by the amount of sedimentation, by the varve graphs. The long cycles are shown by the rate of recession. Study of the climatic periods is one of my chief purposes in measuring so great a number of sections and working out the normal curve. For the elimination of local, non-climatic features, material from different lakes is necessary. Therefore at present only parts of the normal curve are fit for the analysis of periods; other parts may be perfectly good but should be controlled. For the analysis of long periods, more detailed studies of the rate of ice retreat are necessary. While time has not permitted 92 ICE RECESSION IN NEW ENGLAND an analysis of the graphs for the recognition of short periods, and the study of long cycles cannot be made without more data, some problems and con- ditions may be pointed out in order to encourage the collecting of more material. RECOGNIZABLE CYCLES The period of 11 years, or the sun-spot cycle, together with its multiples, seems to play a promi- nent réle in the clay sedimentation. In the growth of trees the same cycles are predominant, as Douglass (1919, p. 99) hasshown. He has determined periods of 11 + 2 (5 to 6), II, 2 X II (21 to 24), 3 X 11 G2 to 35), and 3 X 3 X 11 Goo ie aes) years, as well as of 2 years. The lines of recession as drawn on Plate VI do not pretend to give an accurate picture of the vary- ing rate of ice retreat; for that a much more detailed study is necessary. It is likely that the rate varied a good deal more than the map suggests. In the Berkshires, Taylor (1903) has mapped a series of recessional moraines, the most conspicuous of which are reproduced on Plate VI. As Taylor points out, they must represent short periodical halts in the ice retreat. Because of their wide spac- ing they cannot be winter moraines, i.e. moraines pushed together by a slight readvance of the ice edge during the winter after a summer of consider- able recession, but record periods of some length. On the map an attempt has been made to connect two moraines with two positions of the ice edge. Unfortunately, these latter are not accurately fixed. Assuming that the connections are correct, Taylor’s morainic line No. 2 should correspond to the ice edge position 4800, and his line No. 11 to that of 5300. Accordingly, there should be nine Y 17—Annual rate of ice retreat in meters in southern Finland, after Sauramo (1018, Pl. 3). Fic. CLIMATE DURING RECESSION 93 periods marked by moraines in 500 years, which gives the cycles an average length of 55 years. This is exactly five sun-spot cycles. At the present time no period of 55 years seems to be known. If we assume that the nine periods represent 600 years instead of 500, the length of the cycles would be 67 years, that is to say two of Briickner’s 35-year periods. Determination of the length of the period—i.e. the time of recession and halt—by clay measurements would be of very great value. In the clay graphs there are no particularly thin varves which could be supposed to record these halts. It would perhaps be hasty to conclude from this that the pauses were due to increased ice supply rather than to lower temperature and decreased melting. In Sauramo’s (1918, Pl. 3) diagram of the ice retreat in southern Finland, based on a very detailed study, the fluctuations of the rate are striking (Fig. 17). Leaving out of consideration the part —650 to +0, which represents the Fenno-Scandian moraines, the Outer and, the Inner Salpausselka (cf. p. 87), the ice edge halted or receded slowly on four occasions, at —1225, —1050, —880, and —-725. According to Sauramo’s (1918, PI. 4) graphs, the varves are practically normal during the years —1225 to —1221. They are uniformly thin during parts of the halt —1085 to —1035, particularly during —1062 to —1051I. The varves —900 to —872, i.e. those for the whole halt, are especially at Sauramo’s locality 19 thin and uniform. The halt —725 is not distinguishable in the curves. This halt is marked by a chain of transverse eskers (see Sauramo, 1918, Pl. 1). The average length of the periods is 167 years, or five times the Briickner cycle. The facts seem to indicate that the halts were primarily, but not exclusively, due to low temperature. The climate during the ice retreat also underwent changes of longer amplitude. The length of the period recorded by the readvances at Amherst and Claremont is about 1,700, and that by those at Claremont and Inwood about 800 years. One-third to one-fourth of the periods were occupied by readvances of the ice edge. CHAPTER IX THE BEARING OF THESE STUDIES ON PREVIOUS WORK AND ON NEW PROBLEMS PREVIOUS KNOWLEDGE OF THE ICE RETREAT The map compiled by Goldthwait (Pl. VI) illustrates the retreat of the last ice sheet in the Northeastern States. It shows the general direction of the ice flow as based on striae, drumlins, and boulder trains and the outermost limit marked by the terminal moraines; it shows interruptions of the ice retreat as recorded by recessional moraines and other phenomena; it indicates the late glacial marine submergence of the coast region north of Boston and the rate of recession of the ice front as worked out by the clay studies. The ice flow, seen on the map, is, so far as can be judged, that which prevailed during the time of the ice retreat. The center of the ice lobe covering the Northeastern States followed the great topographical lines, the Champlain-Hudson lowland and the Green Mountains, which trend north and south, and flowed directly southward across Vermont. In southern New England, where the relief is less marked and where the ice flow was strong in the valleys but weak in the lee of the highlands, subordinate lobes were developed in the Hudson and Connecticut Valleys. East of the Connecticut River the ice movement diverged toward the southeast. West of the lower Connecticut the motion was somewhat westerly. In the lower and central Hudson region the ice spread strongly toward both sides. During the ice recession the Hudson lobe retired more slowly than the Connecticut lobe and deployed. It invaded western Connecticut and Massachusetts, crossing the earlier direction of the ice flow. The ice front in the Berkshires, as revealed by Taylor’s (1903) studies of the recessional moraines, had a BEARING OF THESE STUDIES 95 northeast-southwest direction. In the Catskill Mountains and northwest of them the trend of the ice edge was northwest- southeast, as shown by T. C. Chamberlin’s and Rich’s studies of moraines and striae. Hence the whole mountain group was covered by a large lobe the eastern edge of which transgressed the border of Connecticut and Massachusetts. When the ice edge had left the Catskill Mountains, the lobe vanished rap- idly, so that at Cohoes the ice front had an almost east-west direction. The ice crossed the Adirondack Mountains in a south- southwest direction, but it was so thin and the movement was so slow that the relative lack of ice south of them caused the lobes on either side to join and cross each other in the Mohawk Valley. In western New York the ice motion was largely determined by the Ontario basin and to some extent by the topography of the Finger Lakes district. CONFIRMATIONS THROUGH THE VARVE STUDIES The geochronological studies confirm the little which was known about the rate of the ice retreat (see pp. 74-84).. Where Emerson at Northampton, Mass., had indications of a halt and readvance, there the clays furnish independent evidence of the same thing. In the same zone as the till-covered varve clays on Lake Winnepesaukee, which Upham described, evidences for a halt are also found on the Connecticut at Claremont. Fifteen miles west of the recessional moraines which Goldthwait mapped at Bethlehem, on the northwestern slope of the White Moun- tains, a readvance is recorded in the clays. In zones where no indications of halts have been found the recession proves to have been more or less rapid. It is the same thing with the trend of the ice edge. The ice front, fixed by connections between Cohoes, N. Y., and Concord, N. H., runs at right angles to the general direction of the ice flow. Likewise the simultaneous uncovering of the site of Hud- 96 ICE RECESSION IN NEW ENGLAND son, N. Y., and the northern border of Massachusetts where this crosses the Connecticut River agrees with the trend of Taylor’s recessional moraines in the Berkshire Hills and with the general direction of the ice movement there. THEIR CONTRIBUTION TO THE PROBLEM OF THE GLACIAL CORRELATION OF THE GREAT LAKES REGION AND NEw ENGLAND One of the great problems in the Quaternary geology of North America is the correlation of the ice retreat in New England with that of the Great Lakes region. Through the detailed studies of Leverett and Taylor the conditions in the last-mentioned area are well known. Morainic lines marking successive ice fronts are mapped and correlated from the Dakotas eastward to western New York. But the correlatives of these moraines in eastern New York and New England are unknown. A comparison of the ice retreat in the two regions, at the first glance, suggests more differences than correspondences. The disagreement, however, is more ostensible than real, and may essentially be due to the different topographic conditions. Most conspicuous is the great abundance of stadial moraines in the Great Lakes region and the practical absence of them in New England. The basins now occupied by the Great Lakes brought about the development of big ice lobes which easily pushed for- ward and, favored by the flatness of the land, built continuous though often weak moraines, while in hilly New England the ice probably readvanced shorter distances and could not pile up any coherent ridges. Some of the faint moraines in the lake region might perhaps rather be ridges of ground moraine than moraines accumulated along the ice front. Whether all the differences between the two regions are due to topographic conditions or not is difficult to tell. It seems possible that there was disagreement also in other respects, most likely in ice supply. It is practically sure, however, that the retreat in both districts was determined primarily by an amelioration of climate and that temperature played the chief rdle also for the readvances. BEARING OF THESE STUDIES 97 Therefore it is highly probable that readvances in the one region were matched by readvances in the other, and periods of recession in the one by those in the other, even if there were some differ- ences in details. The first halt and readvance of the ice in New England north of Hartford, Conn., was in central Massachusetts. In the Hudson Valley this zone comes just south of Kingston, which was uncovered about year 4900 (PI. VI). From Kingston the ice edge, as just mentioned, formed a bow towards the northwest, and so the moraines in the Catskills and northwest of them almost surely record the zone of readvance. Between Utica and Syracuse, as seen on the map, there was a wide re-entrant in the ice sheet, while in the lowland of the Finger Lakes pro- truded a big lobe. Accordingly this readvance seems to be traceable the whole distance from Massachusetts to the western side of the Finger Lakes. In the Erie and adjacent basins glacial Lake Arkona existed during a pause after a recession of the ice front (Taylor, 1915, Pp. 375). The ice barrier is not exactly located; but it stood in about the same position as for Lake Warren, i.e. at the Niagara Falls moraine. Lake Arkona was followed by Lake Whittlesey, which was caused by a marked readvance of the ice (Taylor, 1915, pp. 376 and 384). This ice front is marked by the Port Huron morainic system, which parallels the northeastern and northern coast of the southern peninsula of Michigan 5 to 4o miles inland (Taylor, 1915, Pl. 32), and by the Alden moraine south of Buffalo (Pl. VI). The moraines have been followed from Wisconsin entirely across the Great Lakes region to the Genesee River in western New York. All facts indicate a general and great change in climate which surely ought to have its correla- tive in eastern New York and New England. The Alden moraine points toward the moraines south of the Finger Lakes, which in their turn ought to have their correlatives in the Great Lakes region. Hence it is exceedingly likely that the Port Huron-Alden moraine, the Finger Lakes moraine, and the overridden clays at Northampton, Mass., correspond to each other. 98 ICE RECESSION IN NEW ENGLAND un ii TM Fic. 18—Curve showing drainage during years 5671-5676 recorded at locality a Catskill, N. Y. It probably marks the first escape eastward, through the Mohawk, of the waters of the Great Lakes which occurred during the Lake Wayne stage. Observe the great thickness of the varves after the drainage. Scale, % actual thick- ness. BEARING OF THESE STUDIES 99 About 900 years after the readvance at Amherst, or during years 5671-5676, there occurred a great drainage into glacial Lake Albany. Figure 18 and curve 14 (PI. III) show it at Catskill, 65 miles below the then mouth of the Mohawk at Schenectady. It is registered at other localities up to Albany, but the zone is disturbed. It is the only drainage of importance into Lake Albany for more than 600 years during the ice retreat in the central and upper Hudson region. It records the sudden escape of a large quantity of water, which must have rushed across an abundance of easily eroded material. At the time of the drainage the ice edge stood somewhat south of Cohoes; and west of the Hudson, in all probability, it trended slightly north of west. The ice border may accordingly have left the highland south of the Mohawk River and the varves may record the drainage of a lake through the Mohawk Valley after the small waters, dammed in this valley, had escaped. These seem to have been too small and to have drained out through channels too short to allow them to pick up much material (see Fairchild, 1912). The glacial lake in the Finger Lakes district discharged into the Mohawk waters and accordingly indirectly into Lake Albany (Fairchild, 1909, Pl. 37; 1912, Pl. 15). So it seems most likely that the drainage varves mark the first escape of the vast waters of the Great Lakes region which occurred during the stage known as Lake Wayne, the successor of Lake Whittlesey (Taylor, 1913, p. 306; 1915, p. 386). This supposition is strongly supported by the fact that the varves above the drainage layer are much thicker than those beneath, the first twenty being two and a half times as thick. This shows that the new tributary to Lake Albany brought more material than was supplied by the glacial rivers discharging into the lake and by all other tributaries together. Subsequent to this time of ice retreat the ice front readvanced and closed the outlet at Syracuse (Taylor, 1915, pp. 392 and 398). The resulting stage in the Great Lakes region, Lake Warren, reached from the Finger Lakes district to the Huron basin and discharged westward. The eastern barrier of the lake is probably marked by the Niagara Falls moraine. This marked readvance 100 ICE RECESSION IN NEW ENGLAND of the ice very likely corresponded to the readvance at Claremont and Lake Winnepesaukee, N. H., which occurred about years 6200 to 6500. When the ice edge again withdrew, the outlet of the Great Lakes was shifted for the second time to the Mohawk Valley, and Lake Lundy came into existence (Taylor, 1913, p. 309; 1915, p. 399 and 406 and PI. 19; Fairchild, 1909, Pl. 40). The exact position of the ice barrier of the lake is not known, but it was between the Niagara escarpment and the present shore of Lake Ontario. The beaches of the lake have only moderate strength and indicate a transition stage. As the ice retired and lower outlets were uncovered, the waters fell, so that those over Lake Ontario became separated from those in the Erie basin. In the Ontario basin the transition stages to Lake Iroquois under- went a number of changes of level caused by slight retreats and readvances of the ice front (Taylor, 1913, p. 310; 1915, p. 444). Finally the waters fell, owing to the opening of a lower outlet at Rome, and Lake Iroquois was established. This lake endured for a relatively long time. When the ice front had receded to the northern side of the Adirondacks, Lake Iroquois emptied into Lake Champlain, and the Rome outlet was abandoned (Peet, 1904, p. 660). The lake level sank as the ice withdrew, and finally the sea, entering the submerged St. Lawrence Valley, changed the glacial lake into a marine gulf. Before the marine stage could come into existence the ice had receded beyond the St. Lawrence River. The transition stages preceding Lake Iroquois and the lake itself, therefore, must correspond to the ice recession in northern New England and southeastern Canada. The pre-Iroquois oscillations of the ice border may correspond to the repeated readvances of the ice, which, as a reconnaissance study of the clays seems to show, occurred in the zone between St. Johnsbury and the Canadian frontier. PROBLEMS To BE STUDIED This memoir only treats the main features of the recession of the last ice sheet in New England, while the details and a great BEARING OF THESE STUDIES IOI many questions connected with these researches remain to be studied. Some of these problems may be pointed out. On account of the great depth of the varve sediments the bot- tom layer was reached practically only in the northern part of the Connecticut Valley. It is, therefore, to be hoped that any opportunity to measure the lowest strata be used. Series with bottom varves are necessary for the determination of the exact rate of recession. If a sufficient number of sections with bottom can be secured, the position of the ice front for every winter can be mapped. Such a study has been carried out by De Geer (1912, Pl. 2; 1912a, p. 464) of the Stockholm district. Detailed determination of the rate of recession probably yields the best material known for studying the long climatic periods, i.e. periods from a few decades to hundreds or thousands of years. The zones of readvance of the ice should be studied in detail. The extent and number of oscillations, time involved, and the rate of retreat before and after the readvances are questions of great importance for the understanding of the causes. Stadial moraines should be sought and mapped particularly in these zones. Determination of the length of time of the periods recorded by the stadial moraines which Taylor (1903) mapped in the Berk- shires should be of great climatological interest (cf. p. 92). Clay measurements in other lakes and valleys are very valua- ble for elimination from the normal curve of local, non-climatic features. The history of the lakes presents interesting problems. A detailed study of their water levels is being made by Goldthwait. This will throw light upon the extension of the lakes (cf. p. 9), the sedimentation, the tilting of the land, the changes of level of the lakes due to lowering or raising of their outlets (cf. pp. 8, 51), and so forth. Determination of the minimum duration of the lakes by counting the varves will give an idea of the rate of the warping of the land. The measured profiles represent a vast amount of material for the study of sedimentation. Part of this is given in the descrip- ICE RECESSION IN NEW ENGLAND ; i i | i ] j i i | i | | | i | | | ii] ; 1 | i | i ! | i : ; j nice i i i | | j i : | | tied MRM Te 102 me Fic. 19—Part of curves at localities 27 and 28, near Greenfield, Mass., situated only 600 yards apart. The thick varves, at locality 28, consist of coarse sand, often in lenses. Some varves at locality 27 are also sandy. The elevation of the localities is about the same. The current may have swept over locality 28, but this does not seem to be a satisfactory explanation. Scale, % actual thickness. BEARING OF THESE STUDIES 103 tion of the sections (Ch. III). A closer treatment requires better knowledge of the surfaces of the lakes than we have now. Prob- lems are: the spreading of the sediments in the lakes, 1. e. the decreasing in thickness of the varves and in coarseness of the material outward from the mouth of the glacial river; sedimen- tation and depth of water (cf. Fig. 19 and pp. 51, 69, 82); sedi- mentation and size of the drainage area; fluctuations in the sedi- mentation during the summer, as recorded in thick silty varves; the mechanical and chemical character of the sediments— studied in Sweden by Odén. Drainages of lakes ponded by ice or by glacial deposits consti- tute a subject of interest for detailed study (cf. p. 69). So also do changes in the size of the drainage areas of the lakes, as the ice receded, and their relation to the sedimentation. Driven southward by the ice, plants and animals re-immigrated to the newly exposed land. Hardy species followed closely the receding ice edge, and others came as fast as conditions he- came favorable for them. Remains of the earliest flora are pre- served in the varve clays, and a stratigraphical study of them should be of both botanical and climatological interest. By meas- uring the varve series in which the plant remains occur and identifying these varves with the normal curve, the position of the ice edge, when the plants were embedded, can be fixed. Sandegren’s (1915) study of the post-glacial flora and climate at Ragunda in northern Sweden, as recorded by the plant remains in the varve silts, is a standard work because of its accuracy. Of considerable interest are quantitative and stratigraphic studies of plant pollen in the clays, like those carried out in Sweden by L. von Post and others. The physiographic development and the geologic factors, such as erosion by rivers and by the sea, weathering, etc., can be studied under new conditions when the actual length of time since the release from the ice shall have become known. Knowing that southern New England was uncovered about 5,000 years earlier than the northern part, comparative studies can be made. The question of local glaciers in the Adirondacks, Catskills, and White Mountains, after the departure of the ice sheet, might be settled by studies of the clays. EXPLANATION OF THE MAP ILLUSTRATING THE RECESSION OF THE LAST ICE SHEED FROM NEW ENGLAND AND NEW YORK By J. W. GoLpTHwalIt On this map (PI. VI) have been assembled those observations of glaciation and of glacial recession which, so far as known to the compiler, appear trustworthy and useful as a background for plotting Dr. Antevs’ data. It is fully realized that no com- plete and accurate map of the glaciation of this region can be made without much further field work. New York State, in the western Adirondacks and west and southwest of the Catskills especially, awaits fuller study. Unpublished work by Woodworth and by Alden in Massachusetts and by Rich in the Catskill region will doubtless make some correlations much clearer and more certain than those possible to show at this time. The chief sources of information used are as follows. The titles of the publications referred to will be found, under the author’s name and the year, in the List of References (pp. 108-114). Direction of ice flow, as shown by striae and boulder dispersion In New Hampshire: C. H. Hitchcock (1878), J. W. Goldthwait and F. H. Foster (unpublished data on boulder dispersion). In Vermont: C. H. Hitchcock (1861) and scattered observations in more recent reports of the State Geologist by various investigators. In Massachusetts: E. Hitchcock (1841), B. K. Emerson (1898), and drumlin axes shown on topographic quadrangles of the U. S. Geological Survey. In Rhode Island: N. S. Shaler (1889); also drumlin axes. In Connecticut: W. W. Mather (1843), B. K. Emerson (1898), H. E. Gregory (1906), F. Ward (1920). In New York: T. C. Chamberlin (1883), W. W. Mather (1843), J. F. Kemp and R. Ruedemann (1910), I. H. Ogilvie (1902), H. P. Cushing EXPLANATION OF MAP — 105 1907, 1916), A. P. Brigham (1895), R. S. Tarr (1909), J. M. Clarke (1911), W. J. Miller (1909, 1910, 1914, 1916), H. L. Fairchild (1907), J. B. Woodworth (1901, 1905), J. L. Rich (1906, 1914, 1915), C. E. Gor- don (1911), J. H. Stoller (1911, 1916), H. J. Alling (1916), R. D. Salisbury and others (1902). In New Jersey: R. D. Salisbury and others (1902, Pl. 8; and 1908), J. V. Lewis and H. B. Kiimmel (1915). In Pennsylvania: H. C. Lewis (1884). Because of lack of detailed information it generally has not been possible to discriminate between striae made at different stages of ice recession; hence, in compiling lines of flow, a con- servative attitude has been kept toward the delineation of minor lobes. In the Connecticut, Hudson, and Catskill regions these seem to have been more strongly accentuated than the map indicates, resembling perhaps the more thoroughly studied lobe of the Finger Lakes region. The very wide spread of the Mt. Ascutney boulder train is the best evidence of this. The flow of the ice appears to have been due southward, however, over the entire eastern uplands of Vermont, so that it is a mis- take to regard the southward movement of ice down the Con- necticut Valley as due in any sense to the presence of that valley. Terminal moraines In Massachusetts: J. B. Woodworth (1897). In New York: J. B. Woodworth (1901), M. L. Fuller (1905, 1914). In New Jersey and Pennsylvania: same references as under former heading. Recessional moraines In Maine: F. J. Katz and A. Keith (1917). In New Hampshire: J. W. Goldthwait (1916, and unpublished data). In Massachusetts and Rhode Island: J. B. Woodworth (1896, 1897), F. B. Taylor (1903), W. O. Crosby (1899). In New York: T. C. Chamberlin (1883), F. Leverett (1915), R. S. Tarr (1909), H. L. Fairchild (1907), A. P. Brigham (1898), J. L. Rich (1906, 1914, 1915), F. B. Taylor (1913), C. E. Peet (1904), F. Carney (1909). 106 ICE RECESSION IN’ NEW ENGLAND Only a few of the more distinct lines of recession among those described in southern New England are shown. The “New- ington moraine” of Katz and Keith is shown only in Maine be- cause that part of it which lies in New Hampshire and Massa- chusetts seems to the compiler to consist of a series of local recessional wash plains and morainal embankments whose ice contacts lie in parallel lines which trend perpendicular to the striae. (The local moraines shown on Pl. VI in New Hampshire in the same axis are not a part of the “Newington moraine”.) The lines of moraine in western New York are mapped in some- what contradictory fashion by different investigators, making it difficult to select material consistently; but in the main these follow the courses determined by Leverett and Taylor. Tsobases These are drawn only for southeastern New Hampshire and the adjacent part of Massachusetts, and are based upon detailed observations and measurements by the compiler. Tarr’s 50-foot beaches on Cape Ann are taken as the marine limit at that point. The absence of confirmatory evidence from the Salem-Boston district is puzzling: and the correct course of the isobases in Massachusetts is not known. Studies of the deformed water planes in the Merrimac, Connecticut, and Contoocook Valleys are in progress, but do not yet justify extension of the isobases farther inland than here shown. The probability that the “marine limits” at different localities are not even approxi- mately contemporaneous makes a fuller construction of isobases unwise. Positions of receding ice edge These lines, plotted by Dr. Antevs after data collected by him at the localities shown, give, so far as the facts warrant, the distances uncovered by the receding ice edge each century in the valleys where observations are numerous. Three positions only are plotted in the Hudson Valley, to show how the recession EXPLANATION OF MAP 107 there corresponds with that in New England. Dotted lines indi- cate the probable correlation of Antevs’ ice border lines with Taylor’s recessional moraines in the Berkshires and Rich’s moraines in the Catskills, Peet’s Glens Falls moraine south of Lake George, and the Great Lakes moraines as mapped by Taylor and Leverett. LIST OF REFERENCES ALLING, H. L. (1916). Glacial lakes and other glacial features of the central Adirondacks. Bull. Geol. Soc. of America, Vol. 27, 1916, pp. 645-672. ANDERSSON, GUNNAR, AND BIRGER, SELIM (1912). Den norrlandska florans geografiska férdelning och invandringshistoria. Norrlindskt Handbibliotek No. 5, 1912. Upsala. ANTEVS, ERNST (1915). Landisens recession i nordéstra Skane. Geol. Foren. Férhandl., Vol. 37, 1915, PP. 353-366. Stockholm. ANTEVS, ERNST (1922). On the late-glacial and post-glacial history of the Baltic. Geogr. Review, Vol. 12, No. 4, Oct. 1922. BARRELL, JOSEPH (1915). Factors in movements of the strand line and their results in the Pleistocene and post-Pleistocene. Amer. Journ. of Sci., Ser. 4, Vol. 40, 1915, pp. I-22. BIRGER, SELIM (1912). See ANDERSSON, GUNNAR (I9QI2). BRIGHAM, A. P. (1895). Drift bowlders between the Mohawk and Susquehanna Rivers. Amer. Journ. of Sci., Ser. 3, Vol. 49, 1895, pp. 218-228. BRIGHAM, A. P. (1898). Topography and glacial deposits of Mohawk Valley. Bull. Geol. Soc. of America, Vol. 9, 1898, pp. 183-210. BRUCKNER, EDUARD (1890). Klimaschwankungen seit 1700 nebst Bemerkungen iiber die Klimaschwankungen der Diluvialzeit. Geogr. Abhandl. herausg. von A. Penck, Vol. 4, 1890, No. 2. Vienna. BRUCKNER, EDUARD (1921). Geochronologische Untersuchungen iiber die Dauer der Postglazialzeit in Schweden, in Finnland und in Nord- amerika. Zettschr. fiir Gletscherkunde, Vol. 12, 1921, DD. 39-57. CARLZON-CALDENIUS, CARL (1913). Inlandisens recession mellan Bispgarden och Stugun i Indalsdlvens dalgang i Jamtland. Geol. Foren. Férhandl., Vol. 35, 1913, pp. 311-328 and 348-360. Stockholm. CARNEY, FRANK (1909). The Pleistocene geology of the Moravia quad- rangle, New York. Bull. Scientific Laboratory of Denison Univ., Vol. 14, 1909, PP. 335-442. CHAMBERLIN, T. C. (1883). Terminal moraine of the Second Glacial Epoch. 3rd Ann. Rept. U. S. Geol. Survey, for 1881-82, pp. 291-402. Washington, D. C. 1883. CLARKE, J. M. (1911). Seventh Report of the Director of the Science Division, New York State Museum Bull. No. 149, 19gII. Crossy, W. O. (1899). Geological history of the Nashua valley during the Tertiary and Quaternary periods. Technology Quarterly, Vol. 13, 1890, p. 322. Massachusetts Institute of Technology. Boston. LIST OF REFERENCES 109 CUSHING, H. P. (1907). Geology of the Long Lake quadrangle. New York State Museum Bull. No. 115, 1907. CusHING, H. P. (1916). Geology of the vicinity of Ogdensburg. New York State Museum Bull. No. ror, 1916. CUSHING, H. P.; FAIRCHILD, H. L.; RUEDEMANN, RUDOLF; AND SMYTH, C. H., Jr. (1910). Geology of the Thousand Islands region. New York State Museum Bull. No. 145, 1910. Dana, J. D. (1870). On the geology of the New Haven region, with special reference to the origin of some of its topographical features. Trans. Connecticut Acad. of Arts and Sci., Vol. 2, Part I, 1870, pp. 45-112. New Haven. De GEER, GERARD (1882). Om en postglaciai sinkning i s6dra och mallersta Sverige. Geol. Féren. Férhandl., Vol. 6, 1882, pp. 149-162; reference on p. 159. Stockholm. De GEER, GERARD (1884). Om modjligheten af att inf6ra en kronologi f6r istiden. Geol. Foren. Forhandl., Vol. 7, 1884, p. 3. Stockholm. De GEER, GERARD (1885). Om istidens kronologi. Geol. Féren. Forhandl., Vol. 7, 1885, Dp. 512-513. Stockholm. De GEER, GERARD (1912). A geochronology of the last 12,000 years. Compte Rendu Congrés Géol. Internatl. ad Stockholm, 1910, pp. 241-253. Stockholm, 1912. Dr GEER, GERARD (1912a). Geochronologie der letzten 12,000 Jahre. Geol. Rundschau, Vol. 3, 1912, Dp. 457-471. Leipzig. De GEER, GERARD (1914). Om naturhistoriska kartor 6ver den baltiska dalen. Pop.-Naturvet. Revy, 1914, pp. 189-200. Stockholm. De GEER, GERARD (1921). Correlation of late glacial clay varves in North America with the Swedish time scale. Geol. Féren. Forhandl., Vol. 43, 1921, pp. 70-73. Stockholm. De GEER, GERARD (1921a). Nordamerikas kvartargeologi belyst av den svenska tidskalan, Geol. Foren. Férhandl., Vol. 43, 1921, Dp. 497-499. Stockholm. DILter, J. S. (1898). The geology of Westfield and vicinity, in EMERSON, B. K. (1898), pp. 654-656. Douc ass, A. E. (1919). Climatic cycles and tere oty. Carnegie Instn. Publ. No. 289, Washington, D. C., 1919. EMERSON, B. K. (1887). The Connecticut Lake of the Champlain period, north of Holyoke. Amer. Journ. of Sct., Ser. 3, Vol. 34, 1887, Pp. 404. EMERSON, B. K. (1898). Geology of Old Hampshire County, Mass., comprising Franklin, Hampshire, and Hampden Counties, U. S. Geol. Survey Monograph 29, 1898. EMERSON, B. K. (1898a). Holyoke Folio. U.S. Geol. Survey Geologic Atlas, Folio No. 50, 1898. 110 ICE RECESSION IN NEW ENGLAND FAIRCHILD, H. L. (1907). Drumlins of central western New York. New York State Museum Bull. No. IIT, 1907. FAIRCHILD, H. L. (1909). Glacial waters in central New York. New York State Museum Bull. No. 127, 1909. FAIRCHILD, H. L. (1910). See CUSHING, H. P., and others (1910). FAIRCHILD, H. L. (1912). The glacial waters in the Black and Mohawk valleys. New York State Museum Bull. No. 160, 1912. FAIRCHILD, H. L. (1914). Pleistocene marine submergence of the Connec- ticut and Hudson valleys. Bull. Geol. Soc. of America, Vol. 25, 1914, pp. 63 and 219-242. FAIRCHILD, H. L. (1919). Post-glacial uplift of southern New England. Bull. Geol. Soc. of America, Vol. 30, 1919, DP. 597-036. FULLER, M. L. (1905). Geology of Fishers Island, New York. Bull. Geol. Soc. Amer., Vol. 16, 1905-06, pp. 367-390. FULLER, M. L. (1914). The geology of Long Island, New York. U.S. Geol. Survey Professional Paper 82, 1914. GOLDTHWAIT, J. W. (1916). Glaciation in the White Mountains of New Hampshire. Bull. Geol. Soc. of America, Vol. 27, 1916, pp. 263-— 294. GorRDON, C. E. (1911). Geology of the Poughkeepsie quadrangle. New York State Museum Bull. No. 148, 1911. Grecory, H. E. (1906). Glacial geology, in Manual of the geology of Connecticut, Connecticut State Geol. and Nat. Hist. Survey Bull. 6, DPD. 223-259, 1906. HaGer, K. D. (1861). See Hitchcock, EpwArD, and others (1861). HANN, JULIUS (1911). Klima der gemassigten Zonen und der Polar- zonen, 7x Handbuch der Klimatologie, Vol. 3, Part 2. Stuttgart, I9Ir. HitcuHcock, C. H. (1861). See HircHcocK, EDWARD, and others (1861). Hitcucock, C. H. (1878). Atlas accompanying the report on the geology of New Hampshire. New York, 1878. HITCHCOCK, EDWARD (1841). Final report on the geology of Massachu- setts, Vol. 2, pp. 350-422. Ambherst, 1841. HiTcHcock, EDWARD; HITCHCOCK, EDWARD, Jr.; HAGer A. D.; AND Hitcucock, C. H. (1861). Report on the geology of Vermont, descrip- tive, theoretical, economical, and scenographical. 2 vols., Claremont, IN. EF, 1861. HITCHCOCK, EDWARD, JR. (1861). See HircHcocK, EDWARD, and others (1861). Hosss, W. H. (1911). Characteristics of existing glaciers. New York, IQIl. Hosss, W. H. (19t1a). The Pleistocene glaciation of North America viewed in the light of our knowledge of existing continental glaciers. Bull. Amer. Geogr. Soc., Vol. 43, 1911, Dp. 641-659. LIST OF REFERENCES Ill Hosss, W. H. (1915). The réle of the glacial anticyclone in the air cir- culation of the globe. Proc. Amer. Philos. Soc., Vol. 54, 1915, pp. 185— 225. Philadelphia. HUNTINGTON, ELLSWORTH (1914). The climatic factor as illustrated in arid America. Carnegie Insin. Publ. 192. Washington, D. C., 1914. Katz, F. J., AND KeiTH, A. (1917). The Newington moraine, Maine, New Hampshire, and Massachusetts. U. S. Geol. Survey Professional Paper 1086, 1917. Keita, A. (1917). See Katz, F. J. (1917). Kemp, J. F., AND RUEDEMANN, RUDOLF (1910). Geology of the Elizabeth- town and Port Henry quadrangles. New York State Museum Bull. No. 138, 1910. KINDLE, E. M. (1913a). See TAYLOor, F. B. (1ro13a). Kwapp, G. N. (1902). See SALISBURY, R. D., and others (1902). KGMMEL, H. B. (1902, 1902a, 1915). See Salisbury, R. D., and others (1902 and 1902a) and Lewis, J. V. (1915). LEVERETT, FRANK, AND TAYLOR, F. B. (1915). The Pleistocene of Indiana and Michigan and the history of the Great Lakes. U.S. Geol. Survey Monograph 53, 1915. Lewis, H. C. (1884). Report on the terminal moraine in Pennsylvania and western New York. 2nd Geol. Survey of Pennsylvania, Rept. of Progress Z, 1884. Lewis, J. V., AND KUMMEL, H. B. (1915). The geology of New Jersey. Geol. Survey of New Jersey Bull. 14, 1915. LIDEN, RAGNAR (1911). Om isafsmdltningen och den postglaciala land- hdjningen i Angermanland. Geol. Féren. Férhandl., Vol. 33, 1911, pp. 271-280. Stockholm. LIDEN, RAGNAR (1913). Geokronologiska studier 6fver det finiglaciala skedet i Angermanland. Sveriges Geol. Undersékning, Ser. Ca, No. 9, 1913. Stockholm. LOUGHLIN, G. F. (1905). The clays and clay industry of Connecticut. Connecticut State Geol. and Nat. Hist. Survey Bull. 4, 1905. MaTHErR, W. W. (1843). Geology of the First Geological District, in Geology of New York, Part 1, pp. 158-228. Albany, 1843. Miter, W. J. (1909). Geology of the Remsen quadrangle. New York State Museum Bull. No. 126, 1909. MiLier, W. J. (1910). Geology of the Port Leyden quadrangle, Lewis County, N. Y. New York State Museum Bull. No. 135, 1910. MILLER, W. J. (1914). Geology of the North Creek quadrangle, Warren County, New York. New York State Museum Bull. No. 170, 1914. Miter, W. J. (1916). Geology of the Lake Pleasant quadrangle, Hamil- ton County, New York. New York State Museum Bull. No. 182, 1916. Miter, W. J. (1916a). Geology of the Blue Mountain, New York, quad- rangle. New York State Museum Bull. No. 192, 1916. 112 ICE RECESSION IN NEW ENGLAND ODEN, SVEN (1918). Automatisch registrierbare Methode zur mechan- ischen Bodenanalyse. Bull. Geol. Inst. Upsala, Vol. 16, pp. 15-64, 1918. Opén, SVEN (1919). Uber die Vorbehandlung der Bodenproben zur -mechanischen Analyse. Bull. Geol. Inst. Upsala, Vol. 16, pp. 125-134, IQIQ. ODEN, SVEN, AND REUTERSKIOLD, A. (1919a). Zur Kenntnis des An- cylustons. Bull. Geol. Inst. Upsala, Vol. 16, pp. 135-158, I9QI9Q. ODEN, SVEN (1920). Die automatisch registrierende Apparatur zur mechanischen Bodenanalyse und einige damit ausgefiihrte agro- geologische Untersuchungen. Internail. Mitt. fiir Bodenkunde, 1920, pp. 301-342. Berlin. OciLviz, I. H. (i902). Glacial phenomena in the Adirondacks and Champlain valley. Journ. of Geol., Vol. 10, 1902, pp. 397-412. PEET, C. E. (1902, 1902a). See SALISBURY, R. D., and others, (1902, 1902a). PEET, C. E. (1904). Glacial and post-glacial history of the Hudson and Champlain valleys. Journ. of Geol., Vol. 12, 1904, pp. 415-469 and 617-6061. VON Post, LENNART (1911). En exakt geologisk tiderdkning. Pop.- Naturvet. Revy, I911, pp. 11-20. Stockholm. VON Post, LENNART (1916). Om skogstradpollen i syd svenska torvmos- sef6ljder. Geol. Féren. Férhandl., Vol. 38, 1916, Dp. 384-394. Stock- holm. REUTERSKIOLD, A. (1919a). See ODEN, SVEN (191Qa). RicuH, J. L. (1906). Local glaciation in the Catskill Mountains. Journ. of Geol., Vol. 14, 1906, pp. 113-121. RicuH, J. L. (1914). Divergent ice-flow on the plateau northeast of the Catskill Mountains as revealed by ice-molded topography. Bull. Geol. Soc. of America, Vol. 25, 1914, pp. 68-70. RicuH, J. L. (1915). Notes on the physiography and glacial geology of the northern Catskill Mountains. Amer. Journ. of Sci., Ser. 4, Vol. 39, IQI5, Dp. 137-1686. RUEDEMANN, RUDOLF (1910, I9g10a). See Kemp, J. F. (1910), and CUSHING, H. P. (1910). SALISBURY, R. D., Ktimet, H. B., PEET, C. E., AND KNApp, G. N. (1902). The glacial geology of New Jersey. Final Report of the Geol- ogical Survey of New Jersey, Vol. 5, 1902. SALISBURY, R. D., Ktimmet, H. B., anp PEET, C. E. (1902a). New York City Folio. U.S. Geol. Survey Geologic Atlas, Folio No. 83, 1902. SALISBURY, R. D. (1908). Quaternary System, Passaic Folio, N. J.-N. Y., U.S. Geol. Survey Geologic Atlas, Folio No. 157, 1908, D. 14. SANDEGREN, R. (1915). Ragundatraktens postglaciala utvecklings- historia enligt den subfossila florans vittnesbérd. Sveriges Geol. Undersékning, Ser. Ca, No. 12, 1915. Stockholm. SS eee LIST OF REFERENCES 113 SAURAMO, Matti (1918). Geochronologische Studien iiber die spat- glaziale Zeit in Siidfinnland. Bull. Comm. Géol. de Finlande No. 50, 1918; also Fennia, Vol. 41, No. 1, pp. 1-44, Helsingfors, 1918. Sayles, R. W. (1919). Seasonal deposition in aqueo-glacial sediments. Memoirs Museum of Comp. Zodél., Vol. 47, No. 1. Cambridge, Mass., IQIQ. SAyLes, R. W. (1922). The dilemma of the paleoclimatologists. Amer. Journ. of Sci., Ser. 5, Vol. 3, 1922, pp. 456-473. SHALER, N. S. (1889). The conditions of erosion beneath deep glaciers, based upon a study of the boulder train from Iron Hill, Cumberland, R. I. Bull. Museum of Comp. Zoél., Vol. 16, 1889, pp. 185-225. Cam- bridge, Mass. SMITH, ALFRED (1832). On the water courses and the alluvial and rock formations of the Connecticut River valley. Amer. Journ. of Sct. and Arts, Vol. 22, 1832, pp. 205-231. SmyTH, C. H., Jr. (1910). See CusHinG, H. P., and others (1910). STOLLER, J. H. (i911). Glacial geology of the Schenectady quadrangle. New York State Museum Bull. No. 154, 1911. STOLLER, J. H. (1916). Glacial geology of the Saratoga quadrangle. New York State Museum Bull. No. 183, 1916. Tarr, R. S. (1903). Post-glacial and inter-glacial changes of level at Cape Ann, Mass., with a note on the elevated beaches by J. B. Wood- worth. Bull. Museum of Comp. Zodél., Vol. 42, 1903, pp. 181-196. Cambridge, Mass. TarRR, R. S. (1909). Watkins Glen-Catatonk Folio. U.S. Geol. Survey Geologic Atlas, Folio No. 169, 1909. TAyLor, F. B. (1894). The limit of postglacial submergence in the high- lands east of Georgian Bay. Amer. Geologist, Vol. 14, 1894, pp. 273-289. TayLor, F. B. (1903). The correlation and reconstruction of recessional ice borders in Berkshire County, Mass. Journ. of Geol., Vol. 11, 1903, PP. 323-364. TayLor, F. B. (1913). The glacial and postglacial lakes of the Great Lakes region. Ann. Rept. Smithsonian Instn. for 1912, pp. 291-327. TaYLor, F. B., AND KINDLE, E. M. (1913a). Niagara Folio. U. S. Geol. Survey Geologic Atlas, Folio No. 190, 1913. TaAYLor, F. B. (1915). See LEVERETT, FRANK, AND TAYLOR, F. B. (1915). UPHAM, WARREN (1878). Modified drift, in C. H. Hitchcock: Geology of New Hampshire. Concord, N. H., 1878. UPHAM, WARREN (1888). The geology of Carver and Scott Counties, in The Geology of Minnesota, Final Report, Vol. 2, pp. 102-147, Geol. and Nat. Hist. Survey of Minn. 1888. WARD, FREEMAN (1920). The Quaternary geology of the New Haven region, Connecticut. Connecticut State Geol. and Nat. Hist. Survey Bull. 29, 1920. 114 -ICE RECESSION IN NEW ENGLAND WoopwortH, J. B. (1896). The retreat of the ice-sheet in the Narragan- sett Bay region. Amer. Geologist, Vol. 18, 1896, pp. 150-168. WoopwortTH, J. B. (1897). Some glacial wash-plains of southern New England. Bull. Essex Inst., Vol. 29, 1897. Salem, Mass. WoopwortTH, J. B. (1901). Pleistocene geology of portions of Nassau County and Borough of Queens, New York State Museum Bull. No. 48, I9Ol. WoopwortH, J. B. (1903). See TARR, R. S. (1903). WoopwortTH, J. B. (1905). Pleistocene geology of Mooers quadrangle. New York State Museum Bull. No. 83, 1905. WoopwortH, J. B. (1905a). Ancient water levels of the Champlain and Hudson valleys, New York State Museum Bull. No. 84, 1905. 4h eee wy nee if INDEX Adirondack Mountains, 95, 100, 103, I04 Agassiz, Louis, vii Albany, N. Y., 46, 99 Albany, glacial Lake, 99 Alden, Mr., 104 Alden moraine, 97 American Geographical Society, xii, xiii; photostat copies of the normal curve, 48 Amherst, Mass., 53, 66, 93; clay pits, 18; section showing till and partially folded clay (diagr.), 77 Amherst-Northampton region, oscilla- tions of ice border, 77 Ann, Care, 106 Arkona, glacial Lake, 97 Arthur Kill, 7 Ascutneyville, Vt., bluff, 28 Ashuelot River, 19 Baltic region, 8, 85, 86 Bear Island, 85 Bellows Falls, Vt., lake, 82; localities studied near, 20, 21, 22 Berkshires, 92, 94, 96, 107 Bethlehem, N. H., 83, 95 Bibliography, 108 Blackmount station, N. H., 31 Blekinge, 90 Boscawen, N. H., railroad cut, 27 Boston, 9, 94 Bottom varves, IOI Boulder dispersion, sources of informa- tion, 104 Bow Junction, N. H., 23 Boyce station, N. H., 25 Bradford, Vt., bluff, 30 Brattleboro, Vt., brickyard, 19 Briickner, Eduard, 88, 93 Buffalo, N. Y., 97 Calving, 86, 87 Canterbury station, N. H., clay pit, 27 Catskill, N. Y., 46; drainage curve, 98 (diagr.), 99 Catskill Mountains, 95, 97, 103, 104, 107 Chamberlin, T. C., 95 Champlain, Lake, roo Charlestown, N. H., river bluffs, 21, 22 Charter Oak Park, near Hartford, Conn., 11 Chicopee, Mass., brickyard clay pits, 13, 14 Chronology, normal curve and absolute time, 48 Claremont, N. H., 47, 74, 79, 81, 93, 95; 100; localities studied near, 22, 28 Claremont Junction, N. H., clay pit, 23 Clay, disturbances in, 72; type of clay and rate of retreat, 84. See also Varves Clay Brook, N. H., bluff, 30— Clay Point, near Wolfeboro, N.H., 81 Climate, during recession, 89; Sweden and New England, 90 Climatic periodicity, 91 Coeymans, N. Y., 46 Cohoes, N. Y., 46, 95, 99 Concord, N. H., 95; abnormal varves, 69; lake, 82; localities studied near, 236 2A 25. 20527) Conicut station, Vt., ravine, 31 Connecticut River, junction with Passumpsic River, 34, 35, OI, 66; oxbow, 17 Connecticut Valley, correspondences of varve curves with Merrimac and Hudson Valleys, 67; localities studied, 11, 28; maps showing localities studied, 37—44 Connections, 64 Correspondences, 67 Coxsackie, N. Y., 46 Crowfoot Brook, 14 Curves. See Normal curve, Varve curves Cycles, climatic, 92 De Geer, Gerard, viii, 3, 84, 101; Hudson Valley ice recession, 46; New Eng- land and Sweden ice retreat, 48; temperature studies, 85; time scale, xi, 4; Wells River, Vt., and Woodsville, N. H., 32 Disturbances in the clay, 72 Douglass, A. E., 92 118 Drainage varves, 69 Drainages, 70; three drainages into the Connecticut River above its junc- tion with the Passumpsic, 70, 7I East Putney, Vt., railroad cut, 20 East Ryegate, Vi., ravine and blufis, 34 East Windsor Hill, Conn., 13 Easthampton, Mass., 16 Emerson, B. K., 3, 9, 37, 51, 80, 89, 95 Erie, Lake, basin, 97, 100 Fairchild, H. L., 9 Fauna, 89 Fenno-Scandia, 9, 49, 84, 87, 90, 93 Finger Lakes district, 95, 97, 99 Finland, 79, 86, 87; rate of ice retreat, 92 (diagr.), 93 Fisher’s Island, 8 Flora, 103; Northampton varve clay, 89; Sweden, 90 : Forest Park, near Springfield, Mass., 13 Fort Hill station, N. H., railroad cut, 19 Franklin, N. H., clay pit, 27 Genesee River, 97 Glacial lakes. See Lakes Glacial rivers, I, 9 Glacial theory, vii Glaciers, local, 103 Glens Falls, 107 Goldthwait, J. W., xii, 9, 81, 84, 95, IOI; explanation of map (Pl. VI), 104; map of ice retreat, 94; Preface, Vii Great Lakes region, correlation of ice retreat with that of New England, 95; first escape of waters, 98, 99; moraines, I07 Greenfield, Mass., brickyards, 18; part oi curves (diagr.), 102; reliability of varves, 54 Grout station, Vt., localities studied near, 20 Hackensack, N. J., 7, 8 Hadley, Mass., 17 Hampshire Brick Co., I5 Hanover, N. H., 83; localities studied near, 29, 30; thick drainage varve, 70 Hartford, Conn., brickyards, II, 12, 13; reliability of varves, 49; varve number, 49 ICE RECESSION IN NEW ENGLAND Haverhill station, N. H., studied near, 30, 31 Hinsdale, N. H., 55 Hitchcock, C. H., 9, 37, 45 Hitchcock, Edward, vii, 3 Hobbs, W. H., 86 Holyoke, Mass., brickyards, 14, 15 Holycke Brick Co., 14 Holyoke Range, 52, 66 Hookset, N. H., 23 Hudson, N. Y., 46, 96 Hudson River, elevation of lower district, 9 Hudson Valley, 55, 83, 99, 106; cor- respondences with Connecticut and Merrimac Valleys, 67; localities used, 46 Huron, Lake, basin, 99 ravines Ice border, oscillations, 77, 81; rate of Tetreat, 75 Ice flow, direction, sources of informa- tion, 104 Inwood, Vt., 93; localities studied, 35, 36 Iroquois, Lake, 100 Isobases, 106 Jackson, C. T.., vii Jefirey, E. C., 90 Keene, N. H., brickyard, 19 Kingston, N. Y., 97 Lake sediments, 9 Lakes, formation of ice front, 9; glacial lakes outlines in Connecticut and Merrimac Valleys (maps), 37-45; problems, 101; White Mountains, TESTE Late glacial time, definition,xi Leverett, Frank, 96, 107 Lidén, Ragnar, viii, xi; Wells River and Woodsville samples, 32 Little Sugar River, bluff, 22 Littleton, N. H., 83 Localities studied, 11 Long Island, 8 Long Island Sound, 8 Loughlin, G. L., 9, 37 Lundy, Lake, 100 Lynch Brickyard, 14 INDEX Map illustrating the recession, opp. 120; explanation, 104 Marine clays, 3 Mascoma River, 20, 58 Mather, W. W., vii Mathews, E. B., xii Measuring clay layers (ill.), opp. 5 Merrimac Valley, 82; correspondences of varve curves with Connecticut and Hudson Valleys, 67; localities studied, 23; map of localities studied, 45; reliability of varves, 56 Middletown, Conn., 52 Mink Brook, N. H., 29 Mohawk River, 46 Mohawk Valley, 83, 95, 99, 100 Montague City, Mass., brickyards, 18, I9 Moraines, Berkshires, 92; Great Lakes region, 96; sources of information, 105 Narrows, the, 7 National Research Council, xii Nevel’s Brickyard, 12 New England, abundance and quality of material, 65; conditions during deposition of the varve clay, 7; southern, higher elevation in late glacial time, 7 New Haven, Conn., 7, 8 New York (city), 7 New York (state), 95, 96 Newbury, Vt., clay pits, 31 Newington moraine, 106 Niagara Falls, 97, 99 Normal curve, opp. 120; absolute time and, 48; method of construction, 47; symbols explained, 48 North Charlestown, N. H., 22 Northampton, Mass., 66, 95; brick- yards, 16, 17; flora in varve clay, 89; part of curves (diagr.) 78; reliability of varves, 53. See also Amherst- _ Northampton region Northboro station, N. H., clay pit, 30 Northeastern States, previous knowl- edge of ice retreat, 94 Odén, Sven, 103 Ontario, Lake, 100 Ontario, Lake, basin, 95 119 Oscillations of ice border, Ambherst- Northampton region, 77; Lake Winnepesaukee region, 81 Oxbow of Connecticut River, 17 Park Brickyard, It Passumpsic, Vt., slide, 36 Passumpsic River, junction with Con- necticut River, 34, 35, 61, 66 Passumpsic Valley, 66, 83 Pecowsic Brook, 13 Peetu Cai ato7 Pemproke, N. H., 23 Penacook station, N. H., 26 Periodicity, climatic, 91 Peripheral land, rising of, 8 Plants, pollen in clays, 103. See also Flora Podunk River, 12 Port Huron morainic system, 97 Post, Lennart von, 103 Post-glacial time, definition, xi Precipitation, 85, 86, 87 Previous knowledge of ice retreat, 94 Problems to be studied, 100 Putney, Vt., brickyard, 19 Ragunda, xi, 90; flora and climate, 103 Rainfall, 85, 86, 87 Rate of recession, 74, 90 Recession, conditions controlling, 85; previous knowiedge, 94; rate, 74, 90; rate in middle zone, 81; rate in northern zone, 83; rate in southern zone, 76; rate of retreat and type of clay, 84 References, 108 Rich ewes O5 LOA £07 Rome, N. Y., 100 St. Johnsbury, Vt., 83, 100; slide near, 36 St. Lawrence Valley, 100 Salpausselka, 87, 93 Sandegren, R., 103 Sauramo, Maiti, 79, 88, 92, 93 Sayles, R. W., xii, xiii, 90 Schenectady, N. Y., 99 Sedimentation problems, IoI, 103 Sediments, 9 Simon Lake, Quebec, varve clay (ill.), Opp. 4 120 Smith. Alfred, 3 South Hadley, Mass., 15 South Hadley Falls, Mass., 14 South Windsor, Conn., 12 Spitsbergen, 85 Springfield, Mass., brickyards, 13; reliability of varves, 49 Stockholm, ror Stockport, N. Y., 46 Stony Brook, South Hadley, Mass., 15 Stoughton’s Brook, 13 Striae, sources of information, 104 Sugar Ball Bluff, N. H., 25 Sugar River, 28 Suncook, N. H., 23 Suncook River, late glacial, 57 Superior, Lake, 87 Sverige Amerika Stiftelsen, xii Sweden, flora, 90; ice retreat, xi; ice retreat as compared with New England, 48; rate of ice retreat, 90; temperature, 85, 86 Syracuse, N. Y., 97, 99 DLatr. R.S:, 106 Taylor, F. B., 3, 92, 95, 96, 107 Temperature, 85, 80. See also Climate Topography, influence on rate of recession, 87 Turners Falls, Mass., brickyard, 19 Upham, Warren, 3, 81, 82, 95 Utica, N. Y., 97 Varve clay, formation, I; manner of deposition (ill.), 2; method of investigation, 3 Varve curves, agreement from widely separated localities, 67; examples illustrating agreement, 65 ICE RECESSION IN NEW ENGLAND Varve studies, bearing on previous work, 94; confirmations, 95; contri- bution to the problem of glacial correlation of: Great Lakes region and New England, 96; future problems, 100 Varves, abnormal, 69; abnormally thick, 69; bottom, 101; connections, 64; definition, xi, 3; drainage varves, 69; exposure of varve clay (ill.), OPD. 4; measuring, 4, opp. 5 (ill.); New England, character, 65; relia- bility of those measured, discussion by groups, 49; thickness, meaning of, 72; value for study, 64 Walker Brook, 28 Warren, Lake, 97, 99 Wayne, Lake, 98, 99 Weirs, N. H., 81 Wells River, Vt., De Geer’s locality, 32; localities studied near, 31 Westboro, N. H., localities studied near, 29 Westfield, Mass., brickyard clay pits, 15, 16 Westminster station, Vt., slide and bluff near, 21 White Mountains, 95, 103; ice-ponded lakes, 71, 7 White River, 58, 68, 83 White River Junction, Vt., ravine, 29 Whittlesey, Lake, 97, 99 Willimansett, Mass., 14 Wilson, Conn., 12 Windsor, Vt., bluff near, 28 Winnepesaukee, Lake, 95, 100; oscilla- tions of the ice border in the region, 81 Wolfeboro, N. H., 81 Voodsville, N. H., 10, 84; De Geer’s locality, 32; localities studied near. 30, 31, 32; 33, 34> reliability oat varves, 59, 60 Woodworth, J. B., 9, 104 (‘QIOL ‘EML}IO ‘FOI Alomayy DppuDD fo KarAng *70aH ‘Qoqon© ‘AJuNoD surwmeysiury :uOs[iAA “A “WW JO [ ‘Iq wos ‘uorssturtod Aq ‘poonpoidey) Weg AP[D IY} UT ‘o9aqanG ‘eyxey] wouS :APPPIOT “[OMOI} YOIG pue opeds & YIM poyOOUIS SI ATO JY} S9ATCA JY} SULIMSvIUT V1IOJog “AP[D VAIVA JO oINSOdxs UY—z~ ‘DIY RNa 2 . g art TT z A IN TREE Aaa ae = 8 na ‘i ‘ae Fic. 3—View showing the method of measuring the clay lavers on a strip of paper. Locality 67, Hanover, N.H. oc Amer. Geo ] \ att in ire 2/717 3) MASS. HN SRL Rr HN PT | spol [1 AAs Aa alae A name bol A Eee ame a hu i f nt HAA 002@V Sertes V2: 17, Pl. T. A 1 CONN! | iS 1 BR oS |. ui ald ae Antevs-Recesston af Last Ice Sheet in New. ul Amer. Geogr. Suc. Research Sertes N® 11, PLT. CONN 3 9 + [3 ribi =p] BE IE I -I-H-11-|3|-|4|-|5. Hy! Vi LATIN, 8 i mE. 0 ‘pol | | co ; \] Bava 7 i ++ |3 5-43-114114.8} IB: 4 | 8 5 ina MA 7 || | € en | 6}-)5|-|133|=1 [255 T 440} 4 4) 4%) 470) 3 |ASS. i7iz32|-i+= (lia) Winn d CONN) 2-72-3-3-5-6-6 =~ |7h2121213}315{6) 3324576, | i) aol (ejztitstte/)\o|- Perey 2 =) [343 710} 4n8;8) Fla 5) MASS. t g Bi CONN. 16|-|5|-|3| -|234) 3f2|-|5|-|6 zt |2\-15|- 15 y 6 MASS. Woy} (8 t8t9) T+ |4]9¢57oner C3) syne: dB) 1o4i0|-|14]-¢8 5)3]-|I0)-I4)-48 Tl ail St NN tsl-lia z : 3 H oh ae [70 80 i {1 ee \ to) _| | i i WL 14) - 13) - [1 WW} =|12}=|12] 13} ~ [14 52218 }18 I} 12 2418] -|18) lytp742418|— [16] -415) ryt=14 fs} |15} - 118) ~|16} | 12415)- |15} “|! 7 \] Ty AF si-[eh-f8 1 (2418) |18} tT Bl8- Hl lel 46) | \ ei s = MASS. MASS. é 2 7 3} /}3 3 a ena eee —— cases ey oe aoe - 2 2 4 ‘ a Nn iia Blea iia érececnod a Be ¥ oN CSht (2ar TS oe ae ipa y — AY ea ; " Nt at : * er at ete wae Se pone a 5 ane rains re Sena acne rend Amer. Geogr. Soc. Research Serres N? 11, Plil 247247 (22 [T iii mit i 8 MASS: MT nddindkace: An Mass and at || N= MASS | 1:|27+ (2\62/8) | z (hcihiinasceediantinedndl AUNT Dadharree ee anar“nnadh Gaia Pee eo bd _tmer. Geogr Soc Research Series N& M4, PI Antevs-Recession af Last Ica Sheet in New: a 8 SS 4te)- |\6}- |1a)- LO fist i6}8}13 13 ;20;201244 17177415} 16718 j15719:24 24} 22) 0 tg - (a) -|15\- 13415} -|16)- oy a S 5 LN 9 MASS. Sty A [6jazitzaiz4'ze25) fg) - 21/22] 2] lea) faa) - aeiseieiS) HH |Sye-|9)- !\ lal - fa) al fj ja {1 640 10 MASS. ai [2t)-|19)-|19|-|19]-| ery 7sahsjey2Ha isa} sizul THK yateste 7) ape z | ‘11 MASS. 12 MASS. ! cp 1 Ll ze toy tae { f \3! bs if = NII YS Ah a z 3 ial | / at 40) i | Wat . - a SM 22th) i ~ Amer. Geogr Soc.Research Serves N211. Pll 40 (\4 90 | 56 59) : = 4 ) > S oS oO ST OS) a SS a a DP Fd - | | | 5600: 13 |N.|H. | 23) | | Amer: Geogr Soc Research Serves NOM, PLT | | {iit 4 fella =fi]=1)j}-Iy) al HH | = = = 3%" (Bem) = => Sa 3A" (Bem Es 3 IE S = : z —~ 3 t wi 8 r S rz = H =) F =e _— = SASE: = . mo | = a = J a 3 S Ss 4 . 5 SSA a + i i £ BS zi N 3 = § = Zz i 3 > aa 5 =a rr) = S401 S40) = . aie = — ~ ee er oS : a 7 . D orws ol hed eh d Si A ge St am ‘ | aen ee “ ~hy EO siete Te - : sa 2 rand oh ieee i y mt . ~~ shee « Amer. Geogr. Soc. Research Sertes N21, PllV Anters. Recession ot Last Ice Sheet inNewEngland 16\VT.} N.H. Amer: Geogr Soc. Kesearch Sertes NOMPLIV- 5s 6 16 |VT., NJ H. 4 a - -s-I5-| 497 53)| | TH [54 16) -|54]- 155} |565- [55] - | a7 tr Ht |5} Hal 1s} [s5)-|56]- 39 -la Me ‘ileal Wl AI po T at etl ee 35) j Nis) lo) 13 jsi}- FS |Se 738 1314p \ I 16 |VT., Ne HK slate s | jL tio z0 i 50 90 si) | | | E SREPy conan 23 ae loeb ar eL 3} hed 48 58) titled aol lad leap | siz cele 2 + =e = Ze yi = %I {31)-|31]~|31]- |(3)7) 1020 209 =i —————s x Cars = : e ava lel\ | Vis AE elo (A ff 1BVT. NH g g [ 3 3 | LU Td fal b-ball i) 41 1614 (6 + { ga ' 1 (61|- |(60 | =H: \6i ut ia 18) VT. N. H. rs 5 } a és py 5 i = 0 710 720) fl g rm = mat Nh o . 4 i ano , ae 7 aie 2 : 7 “t ‘ - _ eS Cr ra “ei zi 5 yi, TV ; j A \ ‘ > ra va He + SE ge; 4! 5 Asaf dane —eim- | 4 a | : 7 j of 1 —. 1 ' “ 2 ‘eee a 6 | oe i | Nit SG IRANe CANNMNOD yr il Al hd uh Hi wifi ANAte i vy) 1 ba it 1 li Ay me el SAVANNA “aaa eee : fern i = 7400 —— 7202 = —— Tm — 7202 asi = sem) —— 2A" (63cm) a z (Gem) ‘8 “ (20cm) —6° (15cm) E ‘ & & 3 zag 8 =e # ) Mabalrsrss} liek 2 p) Letty (3: pty IE fro}- | (83) = : Es Ed a + Fi z Fi = x : ab : eE $ EI Ee] =e = i : : FE Fi = +3 Zz EI B24 (6em) 6 1 ps2'(6em) a = | : : >| = oO 5 iE 5 = 2 si & 3 == E t 6804 + 5 = = ‘a I 7105 7105, ‘N05 $ z Ht 3 7 4600 Ta 5 + = o wil w + z if = t 3 = i a + i a a = = x= 2 2] 28 Bans = ° N tt 3 = | | —— 3" (9em) 24 n —<— 75m Localit: 1 | Locatit “3I31 Antevs Recession of Last Ice Sheet tnWewBngland ies Arete 10 tantra o—- shares ASOF ie ee tal nites -_ — a tn & ao oO} t “ es Sew Ps Ca een PN er seo tn © CDA ted seit A Vin. 4 ; :: 7 *} oy * gh! aeter= — — i amr aan een Ne ee eee sare ap = “ ° genes Anite EAA YE oP » ~~ ieee ‘ e bX OV! sl j Anters-Recesston afLast Ice Sheet in NewEngtand MAP ILLUSTRATING THE RECESSION OF THE LAST ICE SHEET FROM NEW ENGLAND AND NEW YORK 3 Compiled by J.W. GOLDTHWAILT Scale 1:1,250,000 10 20 30 cy 0 40 50 Miles i 0 10 20 90 40 50 60 70 #0Km Woropersh wn i i« re a ny Copa Ta 22, ly The Amerie Geographical Society OP NeWFOTR Schena, Ig Cohoes; a 9 Albany 4 37 xf Localit hich section YW Generalized lines of direction of gag. /OCalittes at which clay sections ice flow. based on known striae fA ; drumtins, and boulder trans “ke Moraine loops, marking slender AA Boulder trains i 20011 moraines! southern limit of glaciation) 3 Varn in th BE tecessionat moraines, inctuaing SE Moe sllmengence in the recesstonal tce borders tn the GO Terksnives TIS Positions of ice edge tor every 100 years as determined bv-E Antexs 36 were measured by B.Anters lobes at the tce border wasanie Conjectural correlation af re 3299 “cattered morames Merrimac region ee peoLye tn the Merrimac regior ‘ j a napyolomm _ atorsiturdi Nae hh ella ie in 0 salts 8 tha ERNE Ve Pees ton i plana, iy ak nme woe 4-41-44 whabs Saeed Feaet ae ae tt Fiahionretsnseerenel ==) SS ee aaa ena Saat eeeees INSTITUTION LIBRARIES ae 9088 01240 070 Later sheep ee So ee Pi rs oe eres eet Spare rer pean e sar ne EIS ol erararee 55 Da} PEP Sree ice cen Pea ope ens epee bar Farts org eery) saw oars Peer eres! 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