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DEPARTMENT OF THE INTERIOR UNITED STATES GEOLOGICAL SURVEY

PREPARED IN COOPERATION WITH THE COMMONWEALTH OF MASSACHUSETTS DEPARTMENT OF PUBLIC WORKS AND THE STATE OF CONNECTICUT GEOLOGICAL AND NATURAL HISTORY SURVEY ft

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GEOLOGIC QUADRANGLE PREPARED IN COOPERATION WITH SURFFC1AL GEOLOGY THE COMMONWEALT HOF MASSACHUSETTS DEPARTMENT OF PUBLIC WORKS AND ASHLEY FALLS QUADRANGLE, MASS.-CONN. DEPARTMENT OF THE INTERIOR GQ-936 UNITED STATES GEOLOGICAL SURVEY THE STAT EOF CONNECTICUT GEOLOGICAL AND NATURAL HISTORY SURVEY OJGfl III 73° 15' (GREAT BARRINGTON) 5 42 'O~'3O'' INTRODUCTION The next recorded ice-front position is in the Konkapot Val- EXPLANATION The main topographic elements of the Ashley Falls quad- ley about 2 miles north of the Massachusetts border and just rangle include parts of the Berkshire Hills on the east and the south of Konkapot crossroads. Here a small ice block lay at A layer of windblown sitt and sand, locally mixed with frost-disturbed Ilousatonic Valley and the Taconic Mountains on the wyst. the head of a kame terrace, kame (Qcd3), outwash (Qo), and rock fragments, covers part of the surficial deposits but is not shown Many of the valleys and ridges appear to be controlled by the stream-terrace (Qsta) sequence which extends uninterruptedly structure and lithology of the bedrock, although glaciation has from an elevation of about 700 feet above sea level in a broad modified the landscape. Features associated with giaciatiun in- arc to the Housatonic Valley. Textures of this sequence of de­ Qal clude drumlinoid hills, a large delta, kames and kame terraces, posits decrease in size down valley from coarse gravel to sand, and lake-floor deposits. There is no evidence in this quadran- and collapsed and uneven bedding gives way to uncoilapsed Alluvium gle for more than one glaciation; this glaciation, on the basis of and even budding. The downstream edge grades to a sandy, Yellowish-brown, ycllutvish-Tcd. dark'brown, and dark-gray-brmtm gravel, regional evidence, is probably late Wisconsinan in age. Dur- silty composite stream terrace in the Housatonic Valley, which «64 sand, »»//, ami cltty-irizc material. Moderately to well sorted. Moder­ ing deglaciation, wastage of stagnant ice proceeded generally in turn is graded to the Great Falls bedrock threshold near ately to well Klrati/icd. Occurs in siualca awl in flood plains and low terrace* which arc imtndnted every few decades. Typically 10-12 ft from south to north, and glacial melt water was temporarily Falls Village, Conn. This relationship implies that during or above stream level in the Hmtsatovic Valley. Thiclmess typically 75 ft. impounded in the Blackberry and Housatonic River valleys. before the deposition of this sequence, the main Housatonic Generally derived from strcam-tcrracv deposits, lacustrine deposits, and Features that formed in late glacial and (or) Holoccne time Valley was drained of lake water, and stream-terrace deposits till. Scored by meander scars and swales, and locally mantled 6?y or­ include stream-terrace deposits, alluvial-fan deposits, land- formed more or less concomitantly with the outwash deposits 4100C0 F-TET ganic deposits. Underlain by Pleistocene lacustrine deposits in the (MAS5.J Hoitsaiovic Valley n-nd locally in the Konkapol Valley. Soil develop­ slide debris, and talus. of the sequence. ment is minor QUATERNARY HISTORY As stated above, stream-terrace deposits were laid down in the Housatonic Valley while stagnant ice features formed in During at least the final episode of ice movement, glacial ice the tributary valleys. Some of these Housatonic deposits are Of crossed the ridges and valleys in a southeasterly direction, as complex. Their lower sections locally are lacustrine in origin, shown by striae and grooves whose orientations range from and the surface material, mostly sand, is derived from glacio- S.25"E. to S.til°E. This southeasterly direction of ice move­ Alluvial-fan deposits Swamp deposits fluvial material of various ages from the tributary valleys and Gray to gray-brown, snbronndcd to angular, sttnd, Black and brown-hlack silt, clay-size material, and ment is also indicated by the orientation of a few drumlinoid from the upper Housatonic Valley in the Great Barrington and gravel, and boulders, poorly stratified and poorly pent, moderately well sorted avd well to poorly strat­ hills and the distribution of erratics from unique bedrock Stockbridge areas. Subsequently, theso deposits were trenched sorted, in gently sloping fans graded to strea:-.-ter- ified. Occui's on alluviu?n, stream-terrace deposits, sources within or immediately north of the quadrangle. One about 20 feet. Stream-terrace deposits on minor streams are race deposits and alluvium. Occurs as mttck as 20 water-laid iee-co7ttucl deposits, till, and lacustrine source of erratics is June Mountain where the garnet schist ft above stream level. Materials derived frcm till deposits. Thickness from less than lflto more than composed of gravel and, locally, boulder gravel and have been and local bedrock (schist, gneiss, and quartzite) 4fl; measured thickness averages slightly marc than fades of the Walloomsac Formation of Ordovician age crops incised 10 to 20 feet. aft. Locally contains small pcbblvs out northeast of Sheffield Center in the Ashley Falls and Great Barrington qimdranglos. Large crraLics of Ihu June Mountain Modern flood-plain alluvium (Qal), mostly silt and fine sand, facics tie in a crude fan-shaped area southeast of their source was deposited in the Housatonic Valley after trenching of the Qst. outcrops. East of Smith Hollow, blocks lie on both sides of the stream-terrace deposits. Alluviation is a continuing process, road in a well-defined train. Blue-quartz gneiss, another lo- as major floods every few decades inundate the flood-plain alluvium, reaching or barely exceeding the level of the stream­ cally unique erratic source, occurs on Brush Hill. Southeast Qst of this outcrop area are scattered boulders of gneiss which terrace deposits. As suggested by profile A-A\ net accumula­ 3 have been traced across the Konkapot .River south of Mill Riv- tion is minor, and downcutting is limited by the bedrock thresh- er IN. M. Ratcliffe, written commun., IMS). old at Falls Village, Conn. Along smaller streams, recent al­ Outwash deposits luviation is minimal and is mostly confined to reworking of the Qst* Ught-yclloivish-brown gravel, pebble Till-fabric determinations support in part these data on ice stream-terrace deposits during major floods. sand, and sand, moderately well movement. Two till-fabric determinations, at points Cand D sorted and stratified, generally not on the map, suggest ice movement from the north-northwest Organic deposits have developed in postglacial time in poorly showing channel fillings or collapse drained areas, resulting in widespread but thin deposits of peat structures. Clasts subrowuled to and from the west-northwest, respectively. At two other Qst, rounded. Occur as broad terrace points, A and B, till fabrics are oriented generally north and mixed with silt and clay-size material. Postglacial solution in which viergcs upstream with ice­ carbonate rocks, such as on the west slope of Benton Hill, has ; east-northeast, respectively. The latter two apparently anom­ • :Qed;1 J Stream-terrace deposits contact deposits (Qcd -,} in the Kon­ formed sinks and solution-enlarged joints. Solution has also Lighl-gra-y-brown, dark-yeiloioish­ kapot area, and which merges alous orientations may have been the result of mass move- downstream with stream-terrace produced sinks and disappearing and reappearing streams in brojtm, reddish-brown, liaht-aray, Delta deposits Lake-floor deposits ment on the till slopes. Thus, it appears that ice flow, at least Water-laid ice-contact deposits or ^olive-gray sand and silt, in deposits (Qst3). Typically 20-30 the area north of Brewer Branch Road. and ice-channel deposits Yellowish-brown pebble sand, sand, ft thick and 20-30 ft above present Gray to gray-brown clay, silt, and during the last phase of active movement, was in a general ;ilaces containing pebbles, gravel, sand, moderately xoell sorted, southeasterly direction, which agrees with indications of ice Mass movement formed talus sheets on Toms Hill, small Light-ycUoidsh-brown or yelluvntsh- mill boulders. Moderately well (f nd gravel of mixed sizes. Topset streams beds mostly gravel, moderately well poorly to well stratified, occurring movement throughout the Berkshire Hills and Taconic Moun­ landslides on Rattlesnake Hill, and scattered talus blocks (un­ brown cobble gravel, pebble gravel, sorted and well to nonslratified. in very small outcrops in stream, mapped) on the slopes of Canaan Mountain. Most of this ma­ and pebble sand, viodcratcty to Oer-H-rs tw varrow to nridc.flal to to poorly sorted, and not well strat­ tains of Massachusetts. ified. Foreset beds mostly sand, banks or south of the East Canaan terial appears to be stabilized, and hence it probably was de- poorly sorted and stratified; eon- gnitly sloping and, in part, gently delta at the surface; extensive be­ Evidence of glacial scour and erosion is minimal on the pres- tains collapse stntctures, r.hnmwl rolling terraces. Typically 20-25 •moderately well sorted and strat­ posited during the waning phases of glaciation. fillings, kettles, depressions, and ified, with channel fillings. Fore­ low flood-plain deposits and sent topographic surface, However, the valley fill in the Hou­ fl above present streams and as stream-terrace deposits (noit shown satonic Valley includes glacial-lake deposits to depths of 242 ECONOMIC GEOLOGY bodies of flow till, ntirf, rarely, much as 60 ft thick. Derived from set beds dip generally to the cast. finely divided organic material. till, outwash deposits, and alluvial- Larger fragments subrounded to on map) of the Housatonic and feet; no wells along the river reach bedrock (R. L, Melvin, The gravel and sand resources of the quadrangle can be con- Clasts sttbrounded to rounded. As fan deposits. Subject to rare rounded. Occur as a large flat- Blackberry Valleys. Derived from written commun., 1968; Norviteh and Lamb, 19(i(j, p. 29). This veniently separated into several groups according to origin and much as about ISO ft thick and ISO floods. Soil development as much topped delta avd kame delta de­ rock flour from iitclt-water thick valley fill suggests that the Housatonic Valley may have location. Delta deposits (Qd) near East Canaan consist of an ft above present streams. Derived a.i.Afl. Muvtlcd locally by swavip rived from stagnant ice in the streams, and deposited in local or from mcll-watcr streums flowing Squabble Brook valley. About ISO widespread temporary ice-dammed been overdeepened by ice movement before the valley was estimated 47 million cubic yards of sand and 5 million cubic % deposits, some extensive. Under- from stagnant ice adjacent to lain in Hoiusatonic Valley 6jy sand, ft above present strcamn and more lakes filled with glacial-lake sediments. yards of gravel. Much of the gravel has been removed in the or within the deposits. Soil devel- gravel, and clay deposits as much than ISO ft thick. Foreset beds Qlu, lake-floor deposits, undifferen­ Deposition of till (Qt) was fairly continuous over most of the southern and eastern part of the deposit, primarily from the •2 opment: 3-4 ft of oxidation as ISO fl thick. overlie thick laevstrinc deposits. tiatcd topset beds, but additional large supplies of gravel may occur Qcdj, kames and kame terraces as- Topsct beds commonly removed by Ql], lake-floor deposits associated area, except at higher elevations, on steep slopes, and on sum- 5 Qst4, on the upper Konkapot drain­ sociated with stagnant ice south of quarryhif). Oxidised to about 3-4 with delta deposits (Qd) mits of some lower hills. Maximum till thickness, as indicated in the northern part. The deposit contains about 5 percent silt, • age postdating the Mill Fiver knmc ft. Foreset-topset interface at Konknpot and with onlnmsh de­ deposits by well data, is as much as 50 feet. Most of the exposed till is but the quality of gravel is otherwise high, consisting of more posits (Qo) about 883 ft- above sea level sandy, noninduratcd, and similar to the upper, younger till of than 70 percent quartzite fragments. Pebble lithology of se­ Qst j, in part derived from the Kon­ Qcd2> kames and kame terraces as­ kapot IvttmC'Ovtwash sequence nnd southern New England. However, Taylor (1910, p. 752) found lected surficial deposits of possible economic value is summa­ sociated with stag-mint ice in the in part from sources upstream in evidence of a lower, indurated drift in the gorge of the Housa- rized in the explanation and presented in more detail in table 1. Mill River village area tht Hoiisatonic Valley beyond the Qic, ice-chaniicl deposits associated qnnilranglc boundary tonic River about 8 miles north of Sheffield in the Stockbridge, Water-laid ice-contact (Qcd) deposits occur mostly in the with the Mill River kames Mass., quadrangle. Future deep excavations in the Ashley Konkapot drainage and include a broad kame terrace south of Qst3. deposited in association with Qcd,, kames associated toith stag- stagnant ice bodies in the Mill Falls area may reveal that tho older indurated drift occurs Konkapot crossroads and the kames at Mill River. Together nant ice whose molt water formed Kii'cr nrva here too, as it does in many areas in southern New England. these units contain an estimated 7 million cubic yards of sand the East Canaan delta (Qd) Qst,.)« the Blackberry and Whiting Wastage of the ice in the Konkapol and Blackberry Valleys and about 2 million cubic yards of gravel. Again, much of the Valleys, slightly postdating the occurred in several stages, as recorded by a series of stagnant desirable gravel in the upper part of the deposits has been re- Eu.it Canaan delta ice features. Melting of the ice in the Housatonic Valley took moved. The percentage of silt is probably 5 "percent or less, place without forming stagnant ice features on the valley sides, and the quality of gravel is fairly high; quartzite averages or if these features wore formed they wore eroded or buried about 50 percent of the pebble and cobble fraction, and the car- Qt by lake sediments and alluvium. bonate rock percentage is very low. Perhaps the first area free of ice was in tho southeast cor- Till Outwash deposits (Qo) occur in a broad fan which topograph­ Gray and gray-brown mixtures of clay-size particles, silt, sand, gravel, ner of the quadrangle in the Blackberry Valley. Subsequently, ically extends from the Konkapot kame terrace into the main and boulders, angular to subronnded, nonsorlcd to poorly sorted, con­ melt water flowed into this part of the valley from the upper valley of the Housatonic River. This outwash has an estimated taining small bodies of stratified material but viostly not macroacopicallv Blackberry drainage, from the Whiting River, and from ice as- 17 million cubic yards of sand and about 2 million cubic yards stratified. Occurs as thin to thick sheets,as much as SO ft thick, and sociated with the large kame delta in the lowland southeast of probably much thicker. Derived from bedrock and surficial materials of gravel. Here, too, much of the gravel has been removed at and deposited directly by glacial ice that moved in a generally southeast Rattlesnake Hill [the East Canaan delta). This melt water was the pits, and exploitation is restricted by the water table and direction, as indicated by orientation of striae, drumlinoid hills, and to impounded and locally formed a lake whose highest shoreline conflicts with other land use, such as agriculture. Quality of n lesser extent, by distribution of erratic boulders was slightly more than 883 feet above sea level, which is the the gravel is high, quartzite averaging nearly 70 percent and elevation of the topset-foreset interface in the East Canaan silt composition about 2 percent. kame delta. The direction of melt-water flow, at least during Stream-terrace deposits (Qst) arc very extensive; the surface the later phase of construction of this kame delta was toward material consists mostly of sand or silty sand. Gravel repre­ outcrop or area of closely the east, as indicated by the dip of the foteset bedding. The sents less than 10 percent of the deposit and consists mostly western limit of this lake is unknown, but probably was in the spaced outcrops of small pebbles. Stream-terrace deposits have been used only }, exposures of June Mountain schist Housatonic Valley or near the mouth of the Blackberry River. where quality requirements are low, or where quantity and b, exposures of Brush Hill gneiss No corresponding delta or shore features occur in the Housa- transport distance are cost factors. Moreover, much of the w, deeply weathered bedrock tonic Valley to the south or southwest, as indicated by recon- best agricultural land and many settlements arc on stream­ naissance studies in that area and by tracing the contours of terrace deposits. the topographic maps adjacent to the Ashley Falls quadrangle. Till has been used for road fill in rare instances, and at one If the western limit of this small lake had been blocked in the locality (near Canaan Valley) was used with weathered bed- lower Blackberry Valley, a spillway may have operated Artificial fill rock for dam fill. The abundance of sand and gravel generally afc,enr6mm/c rock tailings; af«, embankment; through the prominent notch on the northwest end of Canaan precludes use of till except for special purposes, such as sealing af,,furnace slan Mountain. The eastern, southern, and northern boundaries of pond basins or dams. this lake wore formed by topographic barriers. Probably by Clay resources are not now exploited, although potential use coincidence, deltas formed in the Stockbridge quadrangle at is high. Surface exposures along tho Konkapot River north- about the same level as the East Canaan lake (fig. 1). How- Contact east of Clayton were used in the past, and bedded clays occur Dashed where approximately located ever, there is no persuasive evidence at present that the East in the stroambank south of Konkapot crossroads. Well and Canaan lake was related to the lake in the Stockbridge area. auger data show that the thick, extensive clay of the Housa- Later a long narrow lake (the Falls Village lake) filled the tonic Valley occurs noar the surface in the Sheffield area; this Housatonic Valley (fig. 1) as shown by the distribution of lake- Strike and dip of foreset bedding Strialion or groove Summit of well-formed drumlin or drumlinoid hill, Spillway for glacial melt Avater or is also suggested by occurrence of clay at a pottery pit just smoothed and streamlined by glacial motion temporary glacial lake floor deposits in wells. The hypothetical outline of the maxi- north of the quadrangle boundary in Sheffield Town. in delta Point of observation at tip of arrow mum extent of these take sediments is projected on the as- Most drumlinoid features arc probably rock-cored. Peat is widespread, but quality is low, and tho recoverable Shaft indicates direction of ice flow sumed tilt rate in this area (about 5 feet per mile). The hypo- amount is generally small. However, it would be valuable lo­ thetical outline of the sediments is outside the known distribu- cally for agricultural purposes, and excavation of the peat beds tion of lacustrine sediments indicated by well records {fig. 1). would provide certain benefits of land reclamation, such as the it The minimum height of this lake was controlled by the bedrock creation of recreation ponds. Landslide Talus threshold in the Housatonic River valley at Great Falls near Falls Village, Conn., presently about 630 feet above sea level TABLE 1. Pebble Uthtyloyy of selected surficial deposits (in percent) (see profile A-A'). This minimum level of the lake is about 30 Di-ltn deposits (Qd) y.-.y.-.-.y feet above the maximum level of the nearby Lime Rock gla- Luculily (121 (13) (14) U5> (16) (171 (18) (19) Areas of erratics from Karst features (K) and areas of extensive cial lake (fig. 1), and about 140 feet below the maximum level QunrUitc n "O M 71 liK unique point sources joint solution features (S) in carbonate bedrock of the East Canaan glacial lake. Therefore, two lake phases oftntbtenti. 1 7 (I (i •1 b, Brush Hill gneiss; j, June Mountain schist existed in the Ashley Fails quadrangle, the relatively exten­ conglomerate sive Falls Village lake, somewhat higher than the Lime Rock Carbonate rock •I 5 i; 4 p (i K 7 ii a glacial lake, and the East Canaan lake, about 140 feet higher Gneiss 5 I) 1 0 i Inferred shorelin e of temporary East than the Falls Village lake level. Schist G 12 IK 11 is Canaan glacial lake Qtuirb o 2 After the lake waters in the East Canaan area drained, grav- Miscellaneous • 1 el, sand, and boulders (Qst]) were deposited in the upper o r, (, 0 u Blackberry and Whiting Valleys. The source of the deposits Tim on '. * " • '." was probably from melt water in the headwaters of the Locality (2) (4) (51 (7) (81 {ID streams beyond the quadrangle boundary. Qunrizilu 21 74 27 1 31 28 Clay-she Silt Sanrl Gravel Boulders Sandstone, 0 (I 5 5 0 e lTuilerinl During or possibly somewhat after tho construction of the conjrlmncrntv East Canaan delta, a body of stagnant ice remained in the vi- CurliimuU' ruck 0 i r> 9 20 cinity of Mill River at a relatively high level, creating a sandy lunuous rock IS la is o I) Textures kame complex (Qcd;,), including a small side-hill esker (Qic). finuiss z\ ii 17 0 2 Although no large exposures of deltaic bedding were observed Schist 88 t M •111 ;u 19 • 2 Quartz (t c> 2 54 0 in the generally slumped exposures of tho Mill River deposits, V.i o 0 H A Till-fabric locality Pebble-count locality the deposits appear to consist of abou t "> feet of horizontally Pebble-count dtttn given in table 1 bedded medium gravel overlying several tens of feet of medi- WaloHtikl icc-cnntncl deposits (Qcd I um sand, similar to the composition of the East Canaan delta. Lucalily 111 (3! (9) (10) (26) j,d,30+ .8 QiiarUitu 42 GO Part of this kame complex may have been built into a local 31 71 65 1.2 pond. Stagnant ice in the Mill River area also produced valley- Sandstone, I! 0 0 4 Mb.* i train sediments at relatively high levels on the Konkapot River Stnitttrraphy of aurficial material , Well or test boring Auger hole or test pit Carbonate rack 0 1 2 n o TIlirkncKS shoion infect, d, clay; og, organic deposits; Stratigraphy shown to 30 ft- or refusal. Open circle Stratigraphy shown to about 2-h fl and its tributaries: these are mapped as stream-terrace depos- {tenuous rock 10 S 0 2 its (Qst ). o $t, silt; t, sand; pi, pebble mind; pci, pebble-cobble salid: indicates well or boring log containing lacustrine dc- 2 flntlii 8 m 2 16 11 PS, prhhlc gravel; eg, cobble gravel; g, grnvel of mixed positH .Schist :>(; v> M R 15 xizes; I, till , Quarts 2 4 0 0 IS v 1 MiswHiineuus 4 0 2 2 73-3O1 73'10F 0 X ­ Outu-iish (Qo) ami slream-Lurrnee (Qst,l deposits

Lucality (6) 12D (22) (231 (24) (25) L Construction materials pit V i ~- • •V'H > H*T! Qunrlxite S3 51 81 1(7 57 Hachurcs indicate a complex of pits Sum 1st i me, i; 2 0 8 f/ conglomerate • ii|ii^ Carbonate rock 0 $ 2 0 0 :t (i 0 I If) 12 li 8 10 4 2' 15' Schist 12 13 12 11 21 Quart?. B 3 I) Miscellaneous o 2 8 'iiiS«=»:.v::sJH::;:*«ft:*-s#,(SOUTH CANAAN) ^ A V KNOWLB0GM ENTS G3G7 IV NE 'Base by U.S. Geological Survey, 1958 Geology mapped by G. W. Holmes in 1962, 1963, The authors are indebted to the Connecticut Department of 10,000-fool grids based on Massachusetts coordinate system, and 1968 and by W. S. Newman in 1968; Highways for some of the resource data; to Nicholas M. Rat­ mainland zone, and Connecticut coordinate system assisted by J. S. Atherton in 1962, and by cliffe and H. Kobcrt Burger, U.S. Geological Survey, for data 1000-meter Universal Transverse Mercator grid ticks, L. 0. Smith, Jr. and John Leftw'rch. Jr. in 1968. on bedrock, boulder trains, glacial striae, and karat features; zone 18, shown in blug data on bedrock outcrops, boulder trains, and to Robert L. Melvin, U.S. Geological Survey, for subsur­ glacial striae, and karst features were face information. {Contours deleted from ponded areas provided by N. M. Ratcliffe and H. R. Burger QUADHANGI.E LOCATION II EKKRENCfiS CITKD CONTOUR INTERVAL 10 FEET Norviteh, R. F., and Lamb, M. E. S., 1966, Housatonic River OATUM IS MEAN SEA LEVEL basin: U.S. Geol. Survey Massachusetts Basic-Data Rept. 9, Ground-Water Ser., 40 p. Taylor, F. B., 1910, Richmond and Great Barrinyton boulder trains: Geol. Soc. America Bull., v. 21, p. 747-752. A 800' -1

EXPLANATION 750' pets

ta ft; Minimum lake level controlled by 2 Falls Village, Conn.,rock threshold HOUSATONIC RIVER of the Lime Rock lake Qst 3 Qal 6K>' ­ 1 42"00' »•.« Lime Rock lake shoreline In Qo, offset " 7 1500 ft E. Gradient of the 60O1 • In Qal, offset Housatonic River 1500 ft E. In Qal, offset Probable extent of lake-floor 640&ft NE. deposits of the Falls Village hike .0:'.» 550' - In Qal, offset In Qst , offset 3100 flW. Terrace levels projected 3 2200 ft E. to line A-A' 50O1 ­ High-level delta

Lake-floor deposits 450' ­ Well containing lake-flour deposits FIGURE 1.—Sketch map Blunting regional relations of lacustrine depuxtlit. 400' 400' N1EHIUH— CEULOI.ICA1. 5UBVCT. WASHINGTON, D.C. — VERTICAL EXAGGERATION X20 PROFILE A-A' HOUSATONIC SURFICIAL GEOLOGIC MAP OF THE ASHLEY FALLS QUADRANGLE, MASSACHUSETTS-CONNECTICUT By G. William Holmes and Walter S. Newman i 1971 For sale by U.S. Geological Survey, price S1.00 f .,' u \