Utah Statewide Archaeological Society Newsletter, Volume 21, Number 1, April 1975

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A~~A£OLw.l M£WSL1;1TE't

s VOLUME 21

APRIL 1975

NO. 1

Utah Archaeolog is distributed quarterly to all DII8JIlbers of the Utah Statewide .lr9,Pat..0].9gS"cal .s.~ci"~7.

A1l. correspondence should be directed to tbe Bditor:

RuJean R. Brunson, 1180 E1g1n Ave., Salt Lake City, Utah 84106.

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NEW5L~TTER UTAH STATEWIDE ARCHAEOLOGICAL SOCIETY

President • • • • • • • • • • • • ••

William Thompson

Vice President • • • • • • • • • • • • • Treasurer

• • • • • • • • • • • • •

•

Deen Caldwell

Shannon Caldwell

Recording Secretary • • • • • • • • • • • Guida Herrick Publications Committee • • • Chairman RuJean R•.. Brunson Rod Chapman Guida Herrick EDITOR'S NOTE We are of material has enabled significant

indebted to Rod Chapman for his energetic gathering for our Newsletter. His diligence in pursuit of material us to print what we consider to be one of the most Newsletters in recent years.

We consider it a rare privilege to be able to print Dr. Lee Clark's papers on his find of a 40,OOO-year-old stone industry on Lake Bonneville's Alpine Beach. This find has important implications for North American pre-history. Dr. Clark is a Salt Lake City dermatologist. This points up the fact that important discoveries about Utah's' pre-history are waiting to be made and the amateur archaeologist CAN make important contributions.

CONTENTS Page 1 Page 6

A 40,OOO-Year-Old Stone Industry on Lake Bonnevillets Alpine Beach The Morphology of Tools on Lake Bonneville's 40,000Year~Dld Alpine Beach

Page 9

Lake Bonneville Stratigraphy

Page 21

Utah Lake Skull Cap

Page 23

Letters

Page 25

Lake Bonneville's Cycles--Climate Clues

Page 27

Chapter News

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A 40,OOO-YEAR~OLD STONE iNDUSTRY ON LAKE BONNEVILLE'S ALpINE BEACH Le~land

L. Clark, M.D.i M.S. Salt Lake City, Utah

, Evidence of man in the New World prior to the Wisconsin gl~ciation has not borne close scrutiny. Sites that may predate the Wisconsin glaoiation, however, continue to be uncovered and appear'to be very old (1).

Such a site is present three miles north-northwest of Lehi, Utah, on the highest shoreline of Lake Bonneville. This shoreline is at an average altitude of about 5,280 and was built by th8J Alpine stage of the lake." This stage has been dated with , a reasonable degree of cer~ainty as follows: CA) Radiocarbon analysis of snail shells gave an average of 40,000+- 2,000 years (2). (B) A second C14 analysis of snail'shells (L-775G) from this location gave an age of 37,000 years. '( C) "Dh230U2~4 snalysis indicated an age of 37,0004-1,500 and 40,000-+-1,500 years (two determinations)(3) ~ The shelf of the beach {figures 1,2) is littered with a variety of stone tools . snd debitage~ The yello~ sand has been stained black with carbon to a depth of 8-12 inohes~ As human debris has accumulated on the shelf, topsoil (promontory soil) ($) has buitl up apace on the surface, which drops away from the lip. This i~ from 1 to 2 feet thick. Its absence on the shelf indicates human habitation at the time th~ l~ke was ,at its all-tim~ high Alpine level. ' The beach is cut at right angles into a flint lens approximstely 120 feet wide and 180 feet long. The long axis of this lens extends north and south. The flint is the center of a tertiary volcanic intrus!on occurring in Tintic quartzite of Cambrian age. Concentric to the flint is hematite, which has weathered to gerusite in exposed areas. The le~s of flint crowns ~ conical knoll. A cliff forms its east flank. The concentric hematite penetrates the lens in micro-and macroscopic veins.

The exposed hematite leached to gerusite and then dissolved completely. This formed two small caves: One at the southern pole of the lens, the other in its southeast flank. Both are in ruins, the anterior chamber having been collapsed in an earthquake. Weathering of fractured surfaces compar~s well with the morainal scarp at the mouth of Litt,le Cottonwood Canyon, 7 miles to the north. This scarp carries a date of 1,000 years or less (5).

The southernmost cave has been excavated to a depth of 4 feet and probably to bedrock. Occasional fires and worked stone indicste definite, if minimal, human use. A constant keening wind and lar~er-than-life rats may have kept utilization to a minimum.

Excavation was carried to what appeared to be bedrock, then abruptly terminated with the sudden appearance of a large, horizontal crack in the east wall.

The second cave f~ces east and is completely sh~ltered frdm the north wind. The boulder-choked entrance pr~cludes the passage of a lerge adult. The slope further ~ast of the cave is accessible and has been excavated via two trenches.

These extend 75 feet down the ,~lope and intersect at least 21 habitation and work levels ': ' (Fi~uraa:I~2}, ~xtonding ~p from. the Alpine beach 38 vertical feet.

There is no human detritus below the Alpine beach.

In the upper levels artifacts occur primaiily in association with fires which were all built against the cliff face. This poeitipn would have produced a maximum of r~flected heat,'and the s ~~ ke would conveni8n~i~ cling to the face, sparing the C8V8 inhabitants.

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A 40,OOO-YEAR-OLD,STONE INDuStRY (Continued) All indications are that this same,~ituatlon applies to the lower levels, with fire sites present in most. Excavation has not been e~tended to the cliff base and bedrock at these levels, in line with pTo'duqirig minimal disturbance of the site, consistent with dating it. ' Implement, a~e almost all m~de fro~ the flint at hand. The exception is an occasional hafl)mer's,tone of "layered brown qlJartz1ts. ,'With the e)(ceptionof the grapefruit-sized ahmmerstones, most tools are rather smail and roughlyflake'd by percus" sion, : ;' .' ~ The most characteristic tool is a biface chopper with carefui::'?retouching of 4-6' mill. of: the cutting edge to pr,oduce a bifacially.concave edge. "", There are thousands upon thousands of flakes; Most. are sma~l~and~bf random shape, Most show,no eVidence of striking platforms and ~o w~ll-devel~~ed bulbs of percussion~ Many may have bee~ produced by freeze~thaw spBiling from tHe cliff face~ : A second characteristic is the keep-shaped scraper or planing tool described

by K. Bartlett (6) in the Talchoco focus, 350 miles south on Little C9lorado River~ This, is a pebble with a raised, ,keel-shaped 4Pper' side (fi9ure 3) and a working edge that is often squa~ed (Figure 4), A" third tool i& '~. hand, ax, polyhedral' in form, with a 4plus wasting of one or both poles and at ieast one longitudinal surface, used as a scraper or plane. Other forms are abrader stones, choppers, and large and small scra~ers, Some implements show 3-4 plLis patin'ation,: ; There are no arrow points~ 1},L,arge bifacial points qccur in levels V and 20.

These share crude bifacial flaking. The technique resembles the other bifacial tools. The le~el V point is 'a,larg~_ palmate, bifacial blade (Figure 5). The 20 point has a 3 plus red-brown patina and ,lies in the level just abo~e the Alpine b8ach~ It looks like nothingao much as one of Bartlett1s keel-shaped scrapers that has been stemmed (Figure, p).

No bones occur with

the:~ools.

Th~re

are no

~r1nding

stones or sherds.

The stone industry here ~esembles Bartlett's Talchoco com~l8~ and,'as~she says, the lower Paleolithic of Europe. None of the above findings are'incompatibl~ with the antiquity of the Alpine beach.

REFERENCES

,I

1. ,Virginia Steen-McIntyre, U. S., Geological Survey, Denver, ,Colo.•,; Roald FrY,xwell, Washington State University, Pull,man, Wash.; find Harold E. Malde, U. 'S. Gec:iic)'gical, Survey, Denver, Colo" Unexpectedly Old .8.m!.' of Deposits .§1 Hueys'Uaco Arohaso .. l£9.ical ~,Valesguillo! Me xico, ';Implied ~ ~ Strati graphic and Petrographic Findings! " '" :

Meyor Rubin and Corrine Alexan-d"er , "U. So' Ge~' logical Survey ' Rad10carb"on Dates V II, ',' American .J9_~ Ef. Science Radiocarbon Supplement, .4 (1960): 129-85, 3. Aaron Kaufamn, IITh230u234 Dating of Carbonates' from Lakes Lahontan and Bonnevpie ll (Ph. D. Thesis, Columbia Universi~y, 1964), 249 p.

2.

4.

R. B., iYlo rrison, Denver, Colo., New ',Evidence, on lake Bonneville Stratigl'El phy and Histo'ry from p'j~omontory Po'iht. utl:ll:!, U. ,5. Geological $urvey Profe, ~sional Paper 525-C (Washington, D~ C. : U. S. Government Printing Office, 1965)" p. Cl14.

(Continued)

Pegs 2

USAS NEWSLETTER

APRIL 1975

A rORTY THOUSAND YEAR-OLD STONE INDUSTRY (Cont.)

References (Continued) Origin of the Present ~ountains and Basins, Utah Geological and ~ineralogical Survey affiliated with the College of ~ines and Miheral'IndUstries, BUlletin 69 (Salt Lake City, Utah: University of Utah, November 1964), p. 43.

5,

6.

K. Bartlett, "A Primitive Stone Industry of the I!.ittle Colorado Valley, Arizona," American Antiguity, (Menasha), B (1943): 266-BB.

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MORPHOLOGY OF STONE TOOLS ON

LAKE BONNEVILLE'S 40,000-YEAR-oLD ALPINE BEACH

By Lea1and L. Clark, M.D" Salt Lake City, utah

m.s.

In 1974 a flint quarry and industry were found on Lake Bonneville's 40,000-yearold A1pin~ Beach~ 3 ~i1es north-northwest of Lehi, Utah (1, 2, '3).

The beach is at an altitude of about 5,280 feet (4). The quarry exploits a 180-foot north-south ~ ridge of tartiary, grey, igneous flint and oolitic hematite intrusive in tintic ' quartzite (5). A 75 -by-45-foo~ mou~d of flint talusfd.~ris, and debitage lies at the eastern bose of the flint rldge, its long axis running , horth-south. It has accumulated to a vertical depth of 38 feet on the beach~ which slopes north to south on a 25 degree angle. The lower pole is at an altitude of about 5,280 feet, the upper at about 5,318 feet. Twenty-one major habitatioH and work levels intervene (1).

The beach matrix "is an admixture of bright ye11ow£and, produced by weathering and wave erosion of the quartzite, itself a cambrian beach (5), and fine brown clay~ Proportions of the latter vary from 5 to 60 percent. The upper 8.12 inches of this matrix are 3-4 plus oarbon stained. No integral car~on has been found on the mound-covered beach or in the adjacent overburden, possibly because of the age of these layers. , . . ", - . , ' A 20-foot north-south trench at the mound's lower pole (1) has produced a ' variety of artifacts, all in or on the beach matrix.

The most sp~ciali~ed are primarily unifacia11y worked flakes (Fig. 1). The striking platforms are shown here vent to the peroussion bulb (lower figures), except for number 112, where it appears in the central figure. These tools have Leval10is-Mousterian affinities not incompatible with current archaeological theory.

Chard feels, on the basis of current Siberian finds, that a Leva110is industry could have been introduced in this area about 40,000 years ago (¢).

One crude point produced in this fashion has a tang 1 5/16 inches in width (Fig. 1, #92). A ,notched abrade~ stone sugg~sts use to smooth shafts of that diameter (Fig. 2, #105). Large abrader stones of coarsely grained hematite have broad smooth convex surfaces, suggesting use as fleshing stones in hide cleaning (Fig. 2, #109). Two parallel incisions on one of these suggest the Sharpening of a split bone weapon or a maker's mark (8) (Fig. 2 #109A).

Wave-rounded pebbles 1!-4 inches in diameter served as hammer stones. Large tabular chunks of flint were beaten into spheroids 2-6 inches in diameter. More ovoid forms were split to serve as hand axes and used without further retouching , Fig. 3).

As noted previously, there may be an association with the Ta1choco complex, 350 miles south of here on the Little Colorado River. Utilized flakes often show a squared cutting edge (Fig 2, #143). There is functional use of cortical stone (Fig. 1, #127 and #112). Tools are often formed from flat-sided material. Unlike Talchoco there is random 1-4 plus patination on some specimens. The tools at Lehi are more advanced and done with more conviction than those on the Little Colorado~ References 1.

Proceedings of the Utah Academy of Sciences, Arts and Letters, 52, part 1 (1975) : 44.

(Continu9d) APRIL 1975 P8g0' 6" .-' " USAS NEWSLETTER

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2.

THE IYlORPHOLOGY OF STONE TOOLS (Contintued) References (Cont.)

Meyer Rubin and Corrine Alexandsr, "U.S. Geological Survey Radiocarbon Datos American Journal of Science Radiocarbon Supplement 2 (1960): 129-85.

V~"

3.

Aaron KaUfman,IITh230U234 Dating of Carbonates from Lake Lahontan end Lake Bonneville ' (Ph~ D~ thesis, Columbia University, 1964), 240 p.

4.

R. B. Morrison, Denver, .Colo., New Evidenoe on Lake Bonn eville Stratigraphy and

His t ory ~ rom Souther . P r omo~t or Point Utah.U. S. Geological Survey Profoes10ns1 Paper 525-C Washington , D. C.: U. S. P r in~9ing' Office, 1965) p. C1l4.

Origin of th e Present Mountain s and Basins, Utah Geological and Mineralogical Survey affiliat ed with the Coll ege of lYlines and Mineral IIndustrise, Bulletin 69 (Salt Lake City, Utah: University of Utah, November 1964). .

5.

6.

C. S. Chard, "The Old World Roots: Review a~d Spec'ulations," Anthropological Papers (Fairbanksl ~n1varsit~ of Alaska), 40, no. 2 (196~).

7.

K. Bartlett, "A Primitive stone Industry of the Little Colorado Valley, Arizona," American Antiquity (Menasha), 8 (1943) 1266-88,

8.

Dr. Philip C! ¡ Hammond, personal communication.

My sincere thanks to Mrs. Alica Feurer for her technical assistance, Ms. Christine Gilmore, the artist, and Mr. Kenneth Clark, owner of the Lahi property.

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GEOLOGICAL SURVEY PROFESSIONAL PAPER 525-C " , Survey Research 1965 Scientific notes and summriries of invs~tig~~tons by members of the Conservation; Geologic,and Water Resources Divisions in Geology, hydrology, and related fie1ds~ Printed"by the United states Government Printing Office, Washington .I . 1965.

NEW EVIDENCE ON LAKE BONNEVILLE STRATIGRAPHY AND HISTORY FROM SOUTHERN PROMONTORY PO,INT, UTAH 8y R; B. Morrison, Denver, Colo.

A9st ract~-- Pluvia1~lake

history revealed by study of new exposures on PromonPoint, Utah, is summarized as follows: Two 1acustra1 episodes which preceded Lake 80nnevil+e are correlated with the Kansan and Illinoian Glaciations, r9spectively~ At least four lake cycles occurred 1n early Lake Bonneville (Alpine) time, which is correlated with the Bull Lake Glaciation. In Lake Bonneville time, correlated with the Pinedale Glaciation, there four lake cycles: two high (earlier) ones recorded by the Bonneville Formation and tWD lower ones by the Draper Formation. Several of the main interlacustral episodes of marked lake recessIon or: desiccation ar-s ' inelr1<ea"ln~~the' deposits by soil profiles;. the newly na-IR9.d--P:romontory Soil., 'iQPiu~.EI.t;iQ.Q-J;I:l.e ..Alpine and Bonneville Fqrmations, is particularly well developed. to~y

The sequences of pluvial-lake deposits of the Great Basin surpass all other types of continental deposits--a1luvial, colluvial, colian, and even 91acial-- in the completeness and sensitivity of their records of Quaternary climatic changes.

The most comple~e records are ' those of late Pleistocene Lake Bonneville and of its neighbor to the west, Lake Lahontan. The history of the lakes can best be deciphered by ~etailed stratigraphic studies in areas of exceptional exposure. Many more large-scale fluctuations of the lakes are now recognized than were known a few years ago. F'ine subdivision of the stratigraphic record and correlation of the thin strat .. igraphio record and correlation of the thin stratigraphic units through their entire altitude range are necessary. to recognize mo~e fluctuations and to determine the maximums and minimums of the various oscillations in lake level. However, in most argesirexposures are not adequate for detailed subdivision of the record and for correlation of thin units. This problem of making reliable correlations has confounded J to some degree, every attempt to unravel the history of Lake Bonneville by intensive stratigraphic study. Every stratigraphic worker has wished for eXposures more continuous than thOSE! provided by the accidents of natural erosion or by small artificial openings such as road cuts and ordinary gravel pits.

These hopes were largely fulfilled during 1955-57 when two huge gravel pits were fJxcaveted for the Southern Pacific Co. on . Promontory Point, Box Elder County, Utah (Fig • .1), to provide fill for completion of the railroad causeway across Great Salt Lake. Exposures in these pits were studied intensively during the summers of 1962 and 1963. The larger gravel pit is in Little Valley, on the western slope of the Promontory Range, five miles·""from the southern end of~PrGroontory Point. It is 1.8 miles long, and along much of its length it is about 0.3 miles wide and extends more than 50 feet below the. original lend surface. The other pit, in a velley two miles to the south, is considerably smaller~ but its lowest exp6sures are at an al~ tituds about 200 feat lower than those in the Little . Valley pit lor within 60 feet of the altitude of Great Salt Lake in June 1951--1~200 feet--that is shown on recent topographic 'quadl'Elngle maps). The.se pits pr.ovide exposures of deposits of Lake Bonneville and other Q"uaternary sedime:nts and soils over a total vertical _

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LAKE BONNEVILLE

STRATIGo~APHY- ... Morrison

range of 900 feet (to within 120 feet of the ~levation of the highsst elevation of the h:i.9hsst shorl?lille); moreover, they are unrivaled for their oontinuity and their completeness of ,¢tratigraphic detElil. Both valleys provided excellent~ lodgement for l~ke 6ediment~'~Md s~eltered the .deposit~ ftom ~uch of the wave erosion~ . . :1_ 0

The hi~tory 6f lake fiuctuatiohs 1e :bBSbd on the alternation, in t~~o,strati­ graphic succession of two types of deposits and features. Lake maximums are recorded by shore deposits at high levels and by deep water sediments which overlie older shore depcsits~ Low levels of the lake are represented by uMbomformities due to s..:besr.i..al erosion, by weathering profiles, by terrestrial sediments that overlie lake dspnslts, and by shore deposits that are intercalated with those formed in deeper water. The altitudes of various lake levels are inferred of rom the altitudes of thedeposits. ",

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Pre-Lake Bonneville Units

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R E A T

Deposits of pre-Lake Bonneville Elge comprise two lacustrine units, two interlacustrine units, two soils with very strong weatheringp~ofiles, Elnd a distinctive beG 6f 'volcanic~9h. these deposits o invariably underlie thei sediments of Laks Bbrihevl11e : and coeval aMd younger sediments.

E A R

S

B A Y

A L T

The older pre-Lake Bonneville lacustrine unit rests directly onbeidrock in° lower oparts L Valley oof the ~i~s; it is'sxposed at aititudes of o A GrElvel beit\l,leen 4,670 ando4~315 feet. The highest Pit K expbsure appears to be below the highest E st'ioreline of the lacuostral inteOrval that this unit· records!. o. The: unit is almost en~ tlrely cobble and pebble grav~l : thElt generPromontory .' , ally tia's well-ro!J'!oded: clElsts, is- nonfossil. iferous, and is -OElS much ElS 30 (set thick. o Southern 'The older pr9 .. L~ke Bonneville interlElcusooot~:t!J~ unit,. r~cElll.y presenOt above the older· lake unit, consists of variable amounts of alluv,~Ell fElO gravel' (generally quite angUlar) r Fig. ol--PROMONTORY POINT, L~ke Bonnecoll~vi4m (~bstiy slopewaih, also angular), ville, Elnd Great Salt LElke.

Elnd, in its uppbr part, loess that commonly * * * * * * contains so·nie interbedded silty to grElvelly collUVium It is exposed Elt altitudes as low ElS 4;31~ feet. At the base of this unit !il.:ooed of pure white volcElnic ash, nearly.2 fSGot,.!n mElximum thickness, crops out lo~~lly on the so~t~ side of the Little . V~lley ~rt~ H. A. Powers (U.S. Geolgi,,~ ... , ~!!rV"'l .. ' 11I'P'I';+-.J..rH"'Io l"'\ommuro\41'"'\1'!'I"-';r"'\P'\s '0':'" --w ~'o'n~':d8-~ .&.L.._oL _ ..... .L. ______ L.J_ .... " ••. J.L.......:. _ .... L.. ....

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Avery strong ~eathering profile~~ ~he pt~-Dimple Dell soil, is dev~ loped on the older pre,-lake Bonneville inter.l.oacU"stt-'irl'so depOSits (or. where they are ' mIssing, on tt,g OJ.d8:t'° pr.e ...Lake Bonneville l,acustrineo'linitJ, but not on younger deposits. It is ~-,~;,~~: ::;[-,}.:l in pJJ:d.3d oC:Gurreni::::,8!?, bene:ath "thsO, 'yo·unger pre-Lake Bonnevill'e lElcustrine r;.:o int.8T.'l z CLiP.o~:~:;:8 ..un~ots at' YocEltions o ~ hre1tered ,from strong WElve or stream erosion.

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It ~s e~;QsGd Elt:Elltituds9 as low El$o4,320 feet. " This soil is ~'~8ep, _som~w~~t :rt?ddish, biown (hue 7,5 YR), is 'mocferntely to strongly clayey, h~s w~ak,to Bt~O~g prismatic blocky ~tructure, and is ElS much ElS 3 feet thick where leElst Page 10 usAs NEWSLETTER" ' APRIL 19.75 0

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LAKE BONNEVILLE STRATIGRAPHY--Morrison eroded. : The underlying Cea (calcareous) horizon is typlcallyfour to five feet thick and is generally well-cemented by CaC03 (cale~um carbonate, lime).

The younge~ pre-Lake Bonneville lbcustrine Unit;abbut 25 feet in maximum thickness. lies on the pre-Dimple Dell soil or~ whets the Boil is missing, on an unweathered older lacustrine of interlacustrlne depo~its~ It consists of gravel, sand, silt and clay, with soma marl and in places smail amounts of tufa. LOQally it contains shells of snails, pelecypOds, or both. This whit is exposed at a1titudes between 4,325 and 4,980 feet; there is no evidence that its highest e~posure records the highest shoreline of the lake in which it was deposited. Two samples of snail shells collected at different times from the same site and bed in the younger pre-Lake Bon~ neville 'lacustrine unit at an altitude of 4,874 feet gave rather widely divergent radiometric ages~ Their radiocarbon ages are 28,5004- 1,500 years and 25,400+-2,500 ., years, respectively~ Two Th 230 .U234 determinations of the age of the first sample are 89,000+-8,000 years and 97,000+-6,000 years, and two like determinations of the age of the seconq sample are 128,000+.. 25,000 years and ' 2l2,000+-30,000 to 40,000 years, The unit that yielded these samples is overlain in the same exposure by fan gravel of the younger pre-Lake Bonneville subaerial unit that bears the Dimple Dell Soil; therefore the snails are certainly of pre-Lake Bonnevillelgge. Consequently, according to the correlations presented in this paper, the C ages are much too young. The Th 230 â&#x20AC;˘ U234 ages are too young for the first sample but probably are in the right order of magnitude for the second sample.

The younger pre-Lake Bonneville interlacustrine unit locally overlies the younger lacustrine unit. It consists of fan gravel (as much as 30 feet thick), colluvium, and a little loess, and thus it resembles the older lacustrine unit except for the ~bsenc8 of volcanic ash. Its lowest exposure is at an altitude of 4,325 feet.

At southern Promontory Point the Dimple Dell Soil, named in a study bf eastern Jordan Valley, Utah (Morrison, 1965a), is developed on deposits of the younger preLake Bonneville interlacustrine unit, or on ol~er deposits where those are absent, but not on the Alpine Formation. This soil is nearly as strongly developed as the pre-Dimple Dell soil, and it is of comparable thickness, but its B horizon typically is slightly less red and slightly less clayey; its structure is less well developed, and its Cea horizon is somewhat thinner and less well cemented. These contrasts are wall 1shown in exposurss which show both soils, seperated by one or more of the inter .. vening sedimentary units. Below the highest shorelines the younger soil is found only where , it was buried by younger deposits, in places especially sheltered from subsequent erosion. Abovo the highest shoreline it is preserved locally as a relict soil on old alluvial fans. Its lowest exposure is at an altitude of 4,328 feet.

Inasmuch as the deposits of Lake Bonneville are correlated with the Bull Lake and Pinedale Glaciations (Morisson, 1961a, bi Richmond, 1061, ~064a), which are correlative with the Wisconsinan stage of Frye and William (1960, 1963; see also Richmond, 1962, table 11; Morrison; end Morrison, 1965b), the Dimple ¡Dell Soil is in turn correlated with the Sangamon Soil of the Great Plains-Midwest region, and there~ fore with,the later part of the 5angamon Interglaciation and with the Sangamonian stage o~ ~rye and Leonard (1952).

The pre-Dimple Dell soi+ is correlated with the Yarmouth Soil of the Great Plains-Midwest region~ Other corr~lations of the pre-Lake Bonneville succession with the Rooky Mountain and midwestern glacial successions are given. According to this reasoning the bed of volcanic ash in the older pre .. Lake' Bonneville interlacustrine unit is lete Kansan, and therefore is equivalent to the Pearlett Ash Member of AP'RIL 1975

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Page 11

LAKE BONNEVILLE STRATIGRAPHY--Morrison the SelPPel FO.rmetion in KeMSElS, supporting the correlation thet' 'has been made by H. A. Powers on petrographic grounds •

: ,;

.Deposits of Lake Bonneville Age The main.stratigrephic units of Lake Bonneville age are subdivided, defined, end correlElted mainly on the basis of intercalated. weathertng profiles (soils),:, which generally are the best stratigraphic ~arkers in the succession. The lacustrine sediments Qf _ this:~ge, .which.Qdmprise the Lake Bonneville Group (Hunt, 1953), EIre hare divided" into -the Alpine (oldest), Bonneville I and Draper Formations. InterHlcus"ti-ine sedi ments (alluv·ium, 'colluvium and loess of se.v.eral ages, in units which are ~6t,.formally hrimed) end .weathering profiles are intercalated with varidUs parts of the,' L.a,k.e, 80nneville "Group~ Alpine Formation . The Alpine Formation, named by Hunt)1953), comprises the earller deposits ~f Lf)ke Bonneville~ It is intermediate in age between ·the. Dimple Dell soil end the P.~omontory Soil (described in the next section of this report) and is correlated with the II yellow clay" of Gilbert (1890); it is e uiv..alent. to the Al ine Member 0 the Little Cottonwood Formation in eastern Jordan Val l e ,lJtah Morrison 1965a.

The Alpins "'lJverlies the Dimple Dell soil-. and the ' you~Q_ge r pre ..Lake Bonneville . subaerial deposits ·wIth minor or no unconformity, and un daJ;'1ies the Promontory Soil an d Jmmed i atel y older s uba er ial saorrnsnt s wi th l ocal unconf ormity. I t is the thickost formation in the Lake Bonnevill e Group, reaching a maximum th i ckness of about 100 feet on southern Promontory Point. , This formation is mainly gravel; it ranges from boulder gravel to pebble gravel, with local interbeds of . sand and a few beds of silt and marl, and at a given 10cal1tycontains the coarses shore gtavel in the beke Bon~eyille Group~ It forms the bulk of three conspi9uo~S bay bars across Little Valley.' .

Several piastems, formed as a result of lake recession, occur within the Alpine T~8Y are marked by'unconformities,which record subaerial exposure and local erosion, and by discontinuous wedge.s of -alluvium or colluvium which in some places bear weak. tp moderately strong weat~aring profiles. These intra-Alpine inte~ lacustrine dias~ems and subaerial units wittli-n the Alpine Formation separate 'the formation into at least four wedges representing separate lake cycles. UnfOrtune"tely in~ivi~ual diastem~.are only locally discernible.

They are especially difficult to t~ace thrtiugh the ~iavelly shore facies zone in determining highest altitude reached by each tongue of the Alpine. Preliminary determinations are as follows: The oldest known wedge of th~ Alpine can be identified at least as high ris 5,050 fe~t; the diastem immediately 'above it is locally -identifi5ble at least as low as 4,700 feet and in places is associated with 1 to 4 feet of colluvium or. alluvium bearing a mod·... erately strong wGathering profile. The second Alpine wedge can be traced as high es 5,150 feet and probably extends somewhat higher; the overlying diastem has been identiFied 8S low as 4 1 850 feet. The third wedge of · the Alpine is exposed in the ' .

Li tUe Valley gravel pit as high as 5,l50'-fset and may extend to the all~time highest· shp;'ElJ.ine of Lake Bonneville (et an everage': 211 tHude of about 5,280 feet). rorm~tion~

That s~dreline is ~a~ked by a pro~inent b0uldery shore terrace which e*tends to 30 feet above the Bonneville shoreline, bears the.Promontory Soil, and is of Slpine age, but whether it marks the secont or the third Alpine maximum. is not cer~ tain e -The diastem overlying the third· wedge can be identified as low as 4, 7PO feet~.

J~ locally bears afoot or two 0~allu01um or cbll~vium and'~ weak 90i1. Th~ y6ung-' 8:;,{; of'. the Alp~ne, wedges, several· feet· in maximum' thickri~ss', I3xtends 'tq an'''altitude ct PPPl"oximately 4,800 fest.

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APRIl. 1975

LAKE BONNEVILLE STRATIGRAPHY--Morrison ~1ls~?formity

end Subaerial Units of Post-Alpine-Pre-Bonneville Aqe

" A widespread unconformity between the Alpine and Bonneville Formations records subaerial exposure . and local erosion; locally a few inches to several feet of alluvium, or both, occurs along this unconformity. A strongly deve10ped weathering profile, the Promontory Soil, is preserved on these deposits. 'or along the unconformity in many places~ The unconformity, subaerial deposits, and soil, identified at altitudes as low as 4,267 feet, attest to a major interval of probably complete lake dessicatisn~

Promontory Soil"The Alpine Formation and the post-Alpine pre-Bonneville subaerial sediments locally bear a strongly de~eloped wea~hering profile that is here hamed the Promon~ tory Soil. This soil typically separates the Alpine and BonneVille rormations in the sheltered places where it has been preservea from wave erasion that occurred during deposition of the Bonneville rormation. Its type locality, and the one that best displays both its stratigraphi6 relations and a well-preserved profile, is a bench foce in the north-central part of the Little Valley gravel pit, in the SEtNEt sed 1, T. 6N., R. 6W., at about 4, 825-~lO feet altitude (Fig. 1). - 1n all exposure's at southern Promontory Point the Promontory Soil is a Brown soil or (locally) a Calcisol~ Its B horizon is 1 to (rar~iy) '2 feet thick, where least eroded, daep b~own (h~e 7;5 YR to YR), generally only slightly clayey" a~d generally structureless (massive), or (locally) weakly pris~atic-blocky. The underlying Cca horizon~ which is commonly the only part of th~ projile preserved in l~cati~ns where the soil has been partly e=oded bywa~~s, h~s moderately strong to : strong calcium carbonate concentration or.

8'!en ce~enta tion ,-and usual~y it is a!;lout -:it feet thick. In :Several places the profile of the Promontory Soil' is compciund, two soil profiles being present bu~ separated by a 'few inches to 2 feet or':alluvium or collubium. - Evidently the intervening s8~iment was , deposited during a minor interval of deposition within the .main soilfoillJin g interval ~ ~Jlll~eville Form~

As it is used -in this discussion the Bonneville -Formation incl udes .all the lake sgdimants that are younger than the Alpine Formation and older th~n the Draper Fbrmaticn (which is discussed in a later section of this report). This usa~e differs sHghtly from the : definition 'by Hunt (1952) and the modification of it hy' 8tssell (J.963, POl 111..,112) ~ They include in the Bonneville the lacustrine sed.'l.ments belie\18d to have besn formed during'the post-Alpine lake cycle in which wat~r ros~ ~ci the Bonneville shoreline and presumably, overflowed -at Red Rock Paes; but they distin~ gu::,sh beds deposited during recession of the .lake, at and below the Provo shoreline, cs the Provo Formation.

(Bisgell also 'included in the Provo the sediments which were laid down in a separate subsequent lake cycle that did not quite reach the Provo sMo:eline and which here are designated as the fb~~~ ~ember of the Drapet Formation.)

The present investiGation showed, however, that on southern Promontory Poi!"lt the Provo shoreline is scarcely marked by .deposits of the Provo Formation. As used here the Bonneville Formation extends below the Provo shoreline and includes the main pa~t of the Provo Formation (in the usage ~f HuMt and of Bissell) but exclud~s the upper pEl.r t, which is here aSSigned to the ()rmper Formation. In this usage the Bonnel/ille Formation is identioal with the combihed Bonneville and Provo Members of the Little Cottonwood Formation in eastern Jordan Val18y~ Utah (Morrison, 1965a), ~nd to the Bonneville Formotio~ as used in the Salt Lake City area (Van Horn, . 1965). Th~s fo~m­ ~tion is younger than the Pio~ontory Sbil ~nd is older than the Granitevill~ Soil (which is discussed below); 'consequently these soils are e~q'811ent mal'kersfor differ-antiating the BonneVille Formation and other lake units'~' APRIL 1975

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Page 13

LAKE BONNEVILLE STRATIGRAPHY--Morrison NOTE: The BonneVille shoreline was defined by Gilbert (1890) as the highest shoreline of Lake Bonneville. He also believed that this shoreline was of the same age 1n all parts of the Lake Bonneville basin, and that it marked the maximum of theleke cycle that overflowed at Red Rock Pass, Idaho. It now is ' established that the highest shoreline of this lake cycle is not everywhere the highest shoreline berauso bf :diffotential warping resulting from isostatic rebound. (At southern Promontory Point one of the shorelines of Alpine age is higher; see above on this page). Therefore, in this paper the term tlBonneville shoreline" refers to the highest shbrelihe of the last lake cycle that rose to the high shore zone, and presumably caused Lake Bonneville to overflow at Red ~ock Pass~

The Bonneville Formation comprises two wedges of lacustrine sediment separated by 'an interlacustrine diastema The lacustrine wedges record at lea.t two deep-lake cyoles, both of which rose above the ~ighest exposures in the gravel pits; one, presumably the seond, rose to tha.~onneville shoreline. The lower wedge is here called the white marl member, after its distinctive offshore facie9 that was first described and named the White Marl by Gilbert (1890). The upper wedge of the Bonneville Formation is here called the upper member.

Th~ shore facies of the white marl member is lacustrine gravel and sand that generally resembles the shors facies of tne Alpine Formation except that typically it is finer grained and has little or no cotirse graveL, evsn on mountain shores that we~s most expo~ed to waves. The offshore faci~sof this me~ber, which commonly begins within a few feet of the shore, is the most prominent and widespread marker unit in the Lake Bonneville succession. At southern Pvom'ontory P.oint this facies is inform~lly named the white marl b~d and typically is silt and silty fine sand; it is generally highly calcareous, thick bedded to massive and faintly laminated â&#x20AC;˘

. Small ga'stropod shells are abundant in many places. This facies is from about one to twenty feet thick, and is pale green to nearly white except in the upper several inches to three feet where it generally is pale pinkish gray to pale pink end forms the "pink marker bed" of Goode and Eardley (1960). At southern Promontoty Point the white marl bed typically is somewhat less white end contains more silt and clay and fewer n~arly pure marl beds than it does in areesfarther west and southwest. The white marl bed at southern Promontory Point is widely expOsed at elevations betw.een 4,320 and 5,2,20 feet in the gravel pits and in a wash-bank exposure e It extends to within 30 feet of the Bonneville shoreline. The gravelly shore facies extends higher, but its upper limit cannot be precisely located in the pOG~ exposures available at this altitude. '.

The diastem that separates the white ma~l member.~rom the upper member became evident only after tracing of beds above and .-below it'. In most places it is a nearly smooth surface that slightly corsscuts th~ bedding of the underlying white marl member locally. In places it is marked by a discontinuous line of pebbles and cobbles and rarely by lenses of colluvial or alluvial gravel.

It has besn traced to an altitude as low as 4,470 feet in Little Valley and as low as 4~823 feet in . the valley to the south. ~t no place does this diastem ¡bear a true weathering profile. The pink zone at the top of the white marl member directly and perSistently underlies this diastem and locally clits ' across underlying strata. The pink color is likely due to incipient weathering dur.ing the lake recession recorded by the diastem.'

The upper member of the 8on~eville Formation is ~imilar to the white marl member, especially in its gravelly to : ~andy shore facies; the two members cannot be different!eted where their shore ',gNIv.els directly overlie onG another. The offshore Page 14

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APRIL 1975

LAKE BONNEVILLE STRATIGRAPHY--Morrleon facies of the upper member is mainly th1ck-to-thin-bedded silty fine sand and medium sEind. The percentage , qf send inc'rEiases upwEll'd. Gastropod shells cOll,lmonly are present and l~c~lly are , ~ o~o.dant. This facies superficially resembles that of the white mEirl me~ber, except ' tha~ it is relatively no~calcareous and generally 1e sa~di9r and somewhat darker~ It commonly is overiain by several feet of regressive shore gravel and gravelly sand of the upper member. ' The upper member extends to the Bonneville shoreline, whch lies et an avorago altitude of about 5,250 feet at Little Valley. Presumably the overflow of Lake ,Bonneville at Red Rock Pass was initiated puring the lake ma~imum, that is marked by this shoreline. There is no indication in the upper member, at L~~tle Valley of a conspicuous recessionEll stillstElnd 'at the Provo, shoreline level.

RadiocElrbon age determinations for BElmples from the Bonneville Formation et Little Valley fit e reasonable chronologie sequence, and support the correlations made herein~ Radiocarbon analysis of wood from a local bog deposit of carbonaceous silt at the base of., the white marl member at 'an al t1 tude of about 4,715 fa.at inaicat..d an age of 20,600 ..-500 years (Rubin and Alexander, 1960, sample W-876). Wood (sample L-775N of Kaufman) from the base of the white marl member at about 4,650 feet was determined to be 20,800 ... .,..:300 years old. The ega of' ,snail sheHs 1n two samples (L-7751 and L-775J) from a lens of lake reworked alluvium 'at the dlastem between the white marl member and upper member, at about 4,890 feet, was determined to ba 15,300+-400 and 15,400.-300 years, respectively. Snail shells from the upper, regressive part of the upper member at about 4,725 feet altitude were found to be 12,780+r~50 years old (Ives and others, 1961, sample W-913); another sample of snail shells! (s~1.l1ple L-7751( of. Kaufman) from the same stratigraphic pOSition but from ' 4,826 t:~e~ altitude was found to be 11,700+-30'0 years old. From this evidence, together ~i~h radiocarbon dates from material from the Bonneville Formation elsewhere, it appear~ that the lake maximum to which the Bonnevillrj shoreline was, related' occurredj,betwesn 15,000. ,and 12,0,00: years ago. ..

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Discori'formity'Between the Bonneville and Draper FormationS! and Associated Subaerial Units

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A disconformity records subaerial exposure and minor erosion between the Bonneville anq Draper Formations. The disconformity is best marked by the Graniteville Soil (9,escribed in the following section) , althaugh. fan gravel and oolluvium, from several'fnches to several feet thick, are assoQi~ted wi~h it lqcallY. The disc~m formity has been identifi~d at an altitude as low as 4,250 feet, and the Graniteville Soil as lo~ as 4,330 feet, attesting to ¡ complete or oea~ly com~lete deSiccation qf the la~8. .1' G~anitevil19 Soil The Graniteville Soil 1s a strongly develaped weathering profil~ in~ermediata in age between the Bonneville Formation (find alluvium and .colluvium af post";Bonneville-pre-Draper age) and the Draper Formation. It was first defined on this basis in eastern Jordan Valley (Morrison, 1965a) where at its type locality it occurs as a relict soil on the Bonneville Member (of the Little Cottonwood Formation) on the Bonneville Member (of the Little Cottonwood Formation) on the Bonneville shoreline terrace. On sauthern Promontory Point the Graniteville -in'vElriably is a Brown soil only slightly less strongly developed than the PromorrtorySoll; it resembles the latt,sr so olosely that , commonly the two so11s are difficult to distinguish unless their stratigraphic relations are exposed ~nseque~ce: .

The B horizon of tho Graniteville is 1 to l~ feet thick, brown (hue 7.5YR to 10 VR, slight1y~ighter than typical for the Promantory Soil), slightly clayey, and generally struot~reless (thoughlocaliy mod~rately prismatic-blocky). The Cca APRIL ",I975

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LAKE BONNEVILLE STRATIGRAPHY--Morrison . horizon generally i~ :about two feet thick, end commonly it has a somewhat less~r '. concentr~tion of CaC03 than the Promontory Soil. Unlike the Promd~tory. the Gr~~ . iteville Soil invariably seems to be a single soil.. The Greniteville is much more,,,, widely.preserved .than the Promontory Soil, with little .or no erosiQn of its prbfile below eVen the highest shoreline of Draper egdi ~b00e :this shoreline it occurs both as a relict soil and as a soil buried by younger eliuvium and collJvium~ Draper FO.r mation The Draper Formation is defin~d in ~asterM Jorden Valley, utah (Morrisoh~ 1965a), as the lake sediments intermediate in age between ths Craniteville and Midvale Soils~ (The Midvale Soil is discussed in the next section of this report.) In Jordan Valley the Draper comprises three wedges of lacustrine sediments separated by interlacustrine diastems; the lacustrine wedges, called the lower, middle, and upper members, respectively, of the Draper Formation record the last three known cycles of Lake Bonneville, ali of which were comparatively low and brief~ At southern Promontory Point only the lower and middle memb~rs have be~n identified. These consist of - di~­ continuous lenses of ~ebble gravel a few inbhesto 4 feet thick. dommoni y separated by ~omparable thicknesses of fan gravel. The lower me~ber extends to about 4~170 feet, and th~ middle member to about 4,470 feet. The , ihtBrlecu6t~ine dia~tem between these two members can be recognized as low 8S 4,280 feet.

POST-LAKE 80NNEVILLE DEPOSITS AND SOILS Post-Lake Bonneville depOSits, overlying the Draper Formation and local subaerial deposits coeval with it, are mainly fan gravel and colluvium (slopewash), and locally, some loess. Two weathered profiles are in places intercalated with these deposits; these are the Midvale Soil (older) and an early Recent ·soil. The postLake' Bonneville. deposits older than the Midvale Soil are carrelate.d with the early part of thm eltithermal interval. They are compoeed mainly of loess and silty alluvium and colluvium derived from the reworking of loess, with few lenses of gravelly colluvium. Their lithology suggests that the interval during which they were deposited was a~id and windy.

Midvale Soil The Midvale Soili defined in eastern Jordan Valley, utah (Mortison, 1965a), is a moderately mature pedocal, considerably less well developed than the Graniteville and Promontory Soils. It has a 8 horizon that generally is less than a foot thick, structuTeless, and light borwn, and grades into a Cca horizon that .is about It feet thisk and has a relatively moderate concentration of calcium carbonate (depending upon parent material). This soil has undergone little subsequent erOSion, and is widespread. It is presumed to have forme d during the later part of the altithermal interval of Antevs (1948, 1952), from about 4,500 to 3iBOO years ago~ ' ·It is El correlative of the Toyah Soil of the Lake Lahontan area, that has been~suggested as a logical marker for the Pleistocene-Recent boundary in the Great Basin (Morrison, 1961c; 1965a, b).

The Midvale Soil is overlain locally by younger gravelly to silty alluvium and slopow8oh that has a maximum thickness of 25 feet. Intercalated with these Recent deposits in pleces i~ another, weakly developed weathering profile, which is corr81at~d with the early Recent soil in eastern Jord~n Valley (Morrison, 1965a). This eoll fs so weakly developed that it has only the bar~st suggestion of a B horizon (a II col 0;.:-11 G horizon of soil scientists), which is generally less thEm 5 inches thick; elsa tha=o commonly is no discernible CaCO~ condentratian below the B horizon.

L.2"";~: ·.::.ct n8 southe~n

Pego: l i5

dop osits of Reqent Promontory Point.

(po'st';'M~dvele) age

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have not been . identified on APRIL 1.975

,LAKE BONNEVILLE STRATIGRAPHY--Morrison Correl~tion of Post-S~ngamon Deposits and Soils With The Rocky Moun,tain. and Midwestern Successions

In recant studies of the Little Cottonwood-Beils Canyon and eastern Jordan Valley areas, souht of Salt Lake City; Utah (Richmond t 1961, 196421; Morrison, 196121, 196521), the Graniteville Soil was not recognized ih the giacial sequence nor tho Promontory Soil in the lacustrine sequence. Hence the Graniteville Soil was incorrectl;.y :, co~relEltod with · the post-Bull Lake soil, end donsequeritly the Bonneville IYlember · uf ~ ~~~ Little Cottonwood Formation (and lake rise to the Bonneville shoteline) was mi~~o.rrolate.d witnthe late stage of the Bull Lake G1aci~tion. From the less amb i"g~.ous succession . revealed at ;southern PromontoriPo-il'lt, it now ie evident that on th~ basis of similar raletive . weatherin ~ profile deu~l6pment the Promontory Soil shOl;l;ld be correlated with the post-Bull Lake 'soil, and the Midvale Soil with tho · .

Pos~.,.P.inedale Soil~ On the basis of this argument and of the available radiocarbon dates .the Bonneville Formation is correlated with (1) tho early· and middle stages 6f· of the. Pinedale Glaciation ,,:,,-the white marl member with the early till, and the upper member with the middle till of this glaciation; and (2) with the Woodfordian substage of Frye and Willman (1960,1963). The Draper Formation is correlated with the upper till of the Pinedale Gl~ci~tion and with the Valderan substage of Frye and Willman (1960, 1963). The Alpine:'Formation now is correlated with' the Bull Lake Glaciation in its entirety, and with ·t he Al tonian substege of Frye end WillmEln (1960, 1963).

The~Promontbry So11 is further correleted with the Farmdalian ~ubstage of Frye end Willman (1960, 1963), and the Graniteville Soil is correlated with the Brady Soil of the Great Plains region and with the Twocreekan substage of Frye and Willman (1960, .

1963).'

Interpretation of Lake History .

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The lake · history recorded in the ·stratigraphic succession at southern Promontory Point can be s~mmerized as follows. .

Two long lasting deep-lake intervals older than Lake Bonneville are evident.

DIJring the. earlier of ·these, of Kansan aga and: correlatDd with 'the Cedar Ridge Glaciation -in the Rocky lYIounte;lins; the lake · rose to· an-altitude of et least ·.4,670 feetJ during the second interval, ·of Illinoian age and corr~latedwith the Sac~gawea Ridge Glaci~tion in the Rocky Mountains, the lake,rosG to at least 4,080 feet~ The · highest exposures of the deposits that redo I'd these laks intervals are below ,the highest sho~eline , ~f Lake BonneVille, but th~ floor of the Great Salt L~ke basin was · several hUr:ldred fe.et lower when these lakes existed (p't ior to subsequent deposition), so the pre-Lake 8qnnevil.l,9 lakes were comparable to Lake Bon'neville in depthe During a major recession~l ' interval .be.tween the time of the two middle Pleistocene lakes the water level fell at least , as lqw as 4,318 feet and the Great Lake baain probably was as completelw desiceated ·as it is now • .Another major interlacustral period occurred after the time of the young~r ,pre-Lake ·Bonneville laks, and thei water level again fell to, ,at least 4,325 fee't altitude, and probably complete desiceation ·occurred, prior to the advent of Lake Bonneville. ,

.~

Early Leke Bonneville history is recorded mainly by the Alpine Formation.

The several interl~6u~trlne diastema within this unit separate at least 4 wedges of lacustrine sediments, recording at least 4 separate lake cycles, all correlative with the Bull Lake Gle-cj,ation. in the Rocky lVlountains. The maximums of these 4 lake cycle~ in this ·arsa appear to have been at altitudes of (Oldest to youngest) at least 5,050 feet, more than 5,100 fest, at least 5,150 feet and probably 5,280 fe~t, and aboul~ 4,800 feet, r8spectivel~ During the int~rv~ning recessions the lake levels went at least as l6w as 4,700, 4,850, and 4,700 feet3 respectively.

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r975

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LAKE BONNEVILLE STRATIGRAPHY--Morr!son Middle Lake Bonneville time, correlative with the Bull· Lake·Pinedale interglaeiation in the Rocky Mountains, was another fairly long interval of probably complete l~ke desiccation.

The later part of this interval is thought to have been consider" , ably warmer than now, on the basis of the strong chemical weathering manifested by I the Prbmontory Soil.

Late Lake Bonneville time is recorded by the Bonneville and Draper Formatiohs and the intervening Graniteville Soil, all correlative with the Pinedale Glaciation 1h the Rocky Mountains. The Bonneville Formation represehts deposition during two lake cycles~ during the first, when the white marl member was deposited, the lake rose tb within a few feet of the Bonneville shoreline; during the second lake cycle, represented by the upper member, the lake rose to ~he ~ohnevi1ie shoreline and pre~ su~ablyoverflowed at Red Rook Pass. Betw~en these cyc1es there was a short-lived but deep recession, to at least as low as 4,323 feet. Following the rise to the Bonneville shoreiinEl was Mother deep recession, and the lake level fell at least as low as 4,250 feet~ Formation bf the Graniteville Soil during this'time interval demonstrates tAt the climate became considerably warmer than that of the present, The final phase of Lake Bonneville is evinced by the Draper Fo~mation, which on southern Promontory Point records two lake cyclos that rose as high as about 4,770 and 4,470 feet, respectively. During the interverling recessional interval the lake level dropped at least as low as 4,280 feet.

Early post-Lake Bonneville time is correlated with the altithermal age or Antevs. During this interval, from about 7,000 or 6,500 years to ebout 3,800 years ago, lake levels remained et least as low as now end probably Great Salt Lake ~as completely dry at times, The early part of this warm interval was arid and characterized by strong wind actiVity. Th~ later part, at the end of tho Pleistocene Epoch, was somewhat less arid, as is shown by the formation of the Midvale Soil.

Data on lake history during the Recent Epoch are not available from this area.

This revised interpretation 6f LaKe Bonneville history supplements all previous ones in ~ecognizing several additional lake cycles in both early end late Laks Bonneville times, If the various Al'pine lake cycles are grouped together as the early dBep lake period of Lake Bonneville, and if the lake cycles recorded by the Bonneville and Draper Formations are grouped as the late deep-lake period, my interpretation is in accord with the conclusions of Gilbert (1890), Antevs (1952, 1955), IVes (1951), Hunt (1953), Bi~sell (1963), and Eardley and others (1957) on tHe reiative ages of, and maximum heights reached during the two main deep-lake interva~9. · The post-Alpine';'preBonneville desiccation wes of interglacial magnitude, but not so lo'ng lasting as inferred by Gilbert and by Eardley and others, The revised ' correlation of the last occupation of the Bonneville shoreline with . the Pinedale Glaciation agrees with the conclusions of Blackwelder (1931), Antevs, as revised (195?,1955), and Ives (1951); its correlation with the middle stade of, this glaciation is sup~orted by this portion of the radiocarbon chronoloby.

REFERENt:;ES Antevs, Ernst, 1948, Climatic Changes and Pre-white Man in the Great Basin with Emphasis on Glacial and Postglacial Times: Utah UniverSity Bulletin, v.38, {lOt lW. p. 168-191.' . ___ 1952, Cenozoic Climates of t l'?ei 'G'reat Basin: Geologische Rundschau, v. 40, no . 1, p. 94-108, (continued on next page.)

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LAKE BONNEVILLE STRATIGRAPHY--Morrison RtFERENCe:S Antevs, ,El:'nst, 1955, Geologic Ciimetic Datirig in the West I Amedc!!)n Antiquity, ,' ", v. 20, no! 4, p. 1 ; Bissell, H. J~, 1963,~ake Bonneviile--G~ology of South~rn Utah Valley, Utahl U.S. Geologicel Survey Professional Paper 257-8, p. 101-130. : Blackweld~r,

,Eliot, 1931, Pleistocene Gleciation in theS1ette Nevada and Basin , Rangesad~olog~ Society of America Bulletin, v. 42, no. 4, p. a65~922.

Eerdley, A. J~, Gvosdetsky, Vasyl, and Marse,ll, R. E., 1,9 57, Hydrology of Lake .Bonneville and Sediments and Soils of its Basin: Geology Society of America Bulletin, v~ 68, no. 9, p. 1141-1202.

Frye,

end Leonard, A. B., 1952, Pleistocene Geology of Kansasl Kensas Geologicel Survey Bulletin 99, 230 p.

J~

C~,

Frye, J. C~, end Willman, H. B., 1960, Clas,s ificetion of the Wisconsinan Stage in the Late Michigan Glecial Lobe: Illinois Geological S~rvey Circular 285, l6p. _

1963, Development of Wisconsinan Classificetion in Illinois Related to Radiocarbon Chronology: Geologicel Society ' ~f America Bulletin, v. 75, p. 501-506.

Gilbert, G~ ,

K!,

1890, Lake Bonneville: U.S. ,Geological Survey Men. 1, 438 p. .

. GQ9de~, H~ D~, and Eardley, A. J. t 1960, Lake Bonnevil~e--A Preliminary Report on the Quaterpary Dopceite o"Little V811sy,Promont6ry Range, Utah (abs.): Geology Society of America Bulletin, v. 71, p. 2035.

Hunt, C. 8~, 1953, General Geology, in Hunt, C. B., Varnes, H. D., and Thomas, H. E., Lake Bonneville--Geology of Northern Utah Valley, Utah: U.S. Geological Survey Profession~l Paper 257-A, p. 11-45.

Ives, P. C~, Levin, Betsy, Robinson, R. D., and Rubin, Meyer, 1964, U.S. Geological Survey Radiocarbon Dates VII, Radiocarbon, v. 6, p. 37-76.

Ives, R. L., 1951, Pleistocene Valley Sediments of the Dugway Area, Utah: Geology Society of Amerioa Bulletin, v. 62, no. 7, p. 781-797.

Leverett, Frank, 1899, The Illinois Glacial Lobel U. S. Geological Survey Monograph 38, 817 p.

Morrison, R~ B~, 1961a, New Evidence on the History of Lake Bonneville From an Area South of Salt Lake City, Utah: Art. 333 in U.S. Geological Survey Pnofessional Paper 424-0, p. 0125-0127. ____~-- 1961b, Correlation of the Deposits of Lakes Lahontan and Bonneville and the Glacial Sequences of the Sierra Nevada ~nd Wasatoh Mountains; Calif09nia, Nevada, and Utah: Article 332 in U.S. Geological Survey Professional Paper 424-0, pl D122-D124. ______- 19610, A Suggested Pleistocene-Recent (Holooene) Boundary for the Great Basin Region, Nevada-Utah: Article 330 in U.S. Geological Survey Professional Paper 424-0, p. 0115-0116. _ _ __ 1965a, Lake Bonneville-Quaternary Stratigraphy of Eastern Jordan Valley, South of Salt Lake City, Utah: U.S. Geological Survey ProfeSsional Paper 477. (In press.)

(Continued on next page)~ APRI L 1975

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STRATIGRAPHY Or LAKE BONNEVILLE--Morrison REFERENCES Mor~ison,

,

R. B~, 1965b, Quaternary Geology of the Great Basin, in Wright, H. D., Frey, O~ G., eds., The Quaternary of the Unite~ S~a~es: Princeton, N.J., Princeton University Press, Review Volume, 1965 Cong., Internat. Assoc. for Quaternary Research (INQUA). (In press)

Richmond, G! M., lU6l, New Evidence of the Age of Lake Bonneville from the Moraines in Little Cottonwood Canyon, Utah; Article 334, in U.S. Geological Survey Professional Paper 424-D, p. D127-0128. . ________ 1962, Quaternary Stratigraphy df the LaSal Mountains, Utah: ·U.S. Geological Survey Professional Paper 324, 135 p~ ______ 1964a, Glaciation of Little Cottonwood and Bells Canyons, Utah: Geological Sutvey Professional Paper 454-D, 160 p. ________ 1961b,

Thre~

U.S.

Pre-Bull Lake tills in the Wind River Mountains, Wyoming--

A Re-Int~rpretation ih Geological Survey Reseirbh 1964: U. S. Geological Survey Professional Paper 501-0, p. DI04-0109.

Rubin, Meyer, and Alexander, Corrine, 1960, U.S. Geological Su~vey Radiocarbon Dates V: Amerioan Journal of Science Radiocarbon Supplement, v. 2, p. 129-185~ Van Horn, Richard, . 1965, Engineering Implications and Geology, Halt of Justice Excavation, Salt Lake City, Utah; sect. 2, Late Wisconsin and Recent StratiGraphy: Utah Geological and Mineralogical Survey Report. (In press)

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UTAH LAKE SKULL ' CAP'

By George H. Hansen Early in July ·1933, three boys, Arlo and James Nutell of, Huntington, Utah, and Elwin Bunnell of Provo, Utah, digging in the mud elong the eBst sho~e of Utah Lake di8covered a skull cap that seems to be worthy of study. It bomes from a locality in the lake that is normally covered by -several feet bf water, and was buried under nine inches of heavy lake bdttdm mud. '.

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Owihg t"~'- the dro~ght which prevailed in Utah in the summer of 1933, an in·" creased demand was made upon the lake water for irrigation purposes. As a result, the l~ke level was lower than ever, before since man be~~n using this water f~r irrigat~on. The lake was actually 10wer~dj through pump~hg operations, approx~mately four feet beloW the natural butlet~ This in turn ex~oS~d for ~he first time wide lake bottom oarea, ~s the shore lihe gradients are ~wtremely gehtle~ Hence the c h~ nce discove~y ~f the skull cap.

Utah· ttake is a remnant fresh water lake of the greater ahcient Lake Bonneville of Pleistocene age, which once ~overed a large part of western Utah. THis lake and its environs furnished an ideal habitat for early man 1M the areB, and they probably gathered around its shore in goodly numbers as attested by the many thousands of flint and stone implements which are found associated with burial mounds bn abahdaned lake levels~ The present sklJIl has ' pI:~ved to be' interesting in two ,ways. First, it comes from a point that would be far out in the normal lake and' from uMderheath a mud l~y­ er that might have required an unusually long time to accumulate. The locality is also a mile north :of· the mouth of the Provo river, a mode~ate sized stream that empties into the lake, and so -:coulCl not have been washed' into position by stream flow. Second, the skull cap itself is entirely different 'from those found in the mounds along the lake shore. It is dolichocephalic in contrast to the typically brachycephalic ones of the mounds and of the local modern Ind~ans. The brain case is reasonably thick' with a somewhat unusual supraorbital development as the accompanying photographs 'and craniogram tracing indicate.

Subsequent excavations in the vicinity of the find as yet have failed to furnish additional fragments of the 'skull or skeleton.

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On the following page are tables which indicate that from the standpoint of purely physical measurements, the Utah lake skull approaches the upper range of Neanderthal possibilities, " : '

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A median craniogram tracing 0 the Utah lake skull various measured,values expressed in millimeters.

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UTAH LAKE SKULL CAP (Continued) When compared with similar measurements made by Klaat~ch, as recorded in "Padof fhe HUman R~6e" by H. H. Wilder (pp. 166-79), the following values seem

igr~ij

mDst

significarit~

Glabella Iniqn

GalCalva rial Vel rial Height H~ight Index HR RHaGI GI cm. cm.

181 ' .., 59.5 32. !ill' 200 'Bl 4015

Breg- GlaFronma be,lla tal Haight Lambda Angle

8regma Angle

GL

BGI

196

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Pi theceln thropus Spy I Spy II

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Average Neanderthal Utah La ke Skull 186 Old Man of Cromagnon 202 Native Australian

BX em.

FGI

87

4414

B215

88.5

47.6

80

168

101

50 56.6

92

193

70

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190 52 • 186 , ' S8° 70· 185

60.5

Glabella Inion Lambda Angle

41' 46 0 57-; 63-73" 44-510 6BI) 51"

Additio,nEll measurements according to A. L. Krocher, as listed on page 32 in his text 'Anthropolcj~ (t943) seem to place' the Utah Lake ,skull values in a similar re1ative ' ~ 08 it lon !

Calvarial Height Index .. BX:GI lYIodern --Races ' ero-Magnon Race Brunn Race Utah 'Lake Skull Neanderthal Man Pithecanthropus Ilnthropoid Apes

59 54 49 43 42 31 '

Bregma Angle BGI ,"

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58 57 52 51 38 42 30 .

Bregma Position Index GN: GI

Frontal , Angle I

FGI

31 33 ':

90

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77

' 35

68 66

35 42 45

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DEPARTMENT OF GEOLOGY BRIGHAM YOUNG UNIVERSITY Provo, Utah

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4891 Sea Ridge Drive Victoria, 8. C. VBY2B3 Celnada Oct. 6, 1975 Dear Dr. Clarki You certainly have an interesting Site, and I would like to he~r Alan Bryan's , opinion on it. The grooved artifact doesn't ring any bells.but then I am hot all that familiar with that area . .. " ,\,', As fcir the quote from me, I would prefer ' the phrasing "Could have boen introduced" as more correctly refiectin~ my views.

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In case you are nDt famUier with , it" t ,he best. ell1d most LJI:l~to~date discussion of the problem of<earl.y ;,man 111 the New World is, the symposium published in Arctlio AnthropDl09ÂĽ , V;blums 8, No. , 2 (1971),. - This , is in the Un-1 versity 6f utah library', - ot' , .0bte'1f'labJ.e from ' the Unive~sity ,of Wi,s consin Press in Madison, Wisconsin'. ' Also ;t'eleven.t . (despi,tQ the title) is Edward Lenning' 8 "Pleistocene" Men in South~ Americ'a. l1 , which eppeared in World Archee olo9Y, Vol. 2, No. 1 (1970), ' I presume you are familiar with jth'e volume The 8 a:r ing Land 8rid'qe

edited by David Hopkins (Stanford, 1967) --e spe cial! y lY!ulle r-B e ck' s pEl pe r:, Another version of the latter appeared in ScienCE) for . Mey 27, 1966 (Vol.

152, pp. 1191-1210), My own most recent. ~tiews, and a rundown .of ,the Siberian evidence, will be found in my final bqok, Northea st A's ia in Prehi s,tory (Unive.rsity of Wisconsin Press, Madison, 1974).

Sincerely, Chester S. Chard

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1002 Ea$t South Temple Salt Leke ' City, utah 84102

Dear Mr. Chapman, Taking umbrage with your concern in the March 1975 Newsletter that readers are indifferent, . I . would guess thet , they , are cowed by the forebidding climate for the amateur that is current in Utah. The newsletter is excellent.

You may find the attached correspondence with Scien ce Ne ws of interest, especially with reference to your article on page 4 of the March issue.

The §cience Ne ws people are accumulating the requested data and I'll send it when available.

Sincerely, Leelend L. Clark,

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December 10, 1975 Miss Susan StrElsburger Science Service, Inc. 1719 N. Street N~S. Washington, D~C. 20036 Dear Susan, Pursuant to our phone oonversatio~ Df l2~9-75_ enclosed are the articles relevant to Morrison's 40,000-year-old·laka :Bonnavlll.e BeEl.ch (Alpine stage) and the stone tools thereon; (1) A 40,000-Yea~-did Ston~ ' Indu9try on Lake Bonneville's Alpine Beach, (2) The Morphology of ,st,one Tools on, Lake Bonneville's 40,000.

Year-Old Alpine Beach, (3) Morrison*s articl~~ tal : the beach levels (this article deals with Bonneville levels younger , than 109,000 years in general and the Alpin~ Beach in ! partidular (~8a pages cli2 arid ' C114)~ (4)Dr. George Hansen's 1931 article, re: a'skuli at the . Brigham Young University ~nthropology Department which t>r. John Sorerison ' (Professor of, l Anthropo~tJgy at Brigham Young University, Pro~o, Utah) · f~llswas cont~mporary ~ with the Alpine Beach. ,This skull, as you will note in the atticl~~' was fdund on tha modern Provo Lake's east beach, one mils north of the mod9~M Prevo River. (5) Dr.Chester S. Chard's letter of Oct. 6, 1975, concerninQ his review of articles 1 and 2 above; (6) Ken Frasatier's current aIlticle "Lake Bonneville's Cycles: Climate Clues," Vol.lOa, No. 19, 289-30.4.'· In terms of oorrbboration; (a) .Dr. Alan Bryan (Department of Anthropology, The University of Alberta, Edmonton, Canada) has examined the site and the artifactsp (b) Dr. Chester S. Chard has examined the manuscripts 1 and 2 above and commented favorably (see his letter on previous page), (c) Dr. Phil Hammond (UniverSity of Utah, D~~artmentof Archaeology~ : Balt Lake City, Utah) has examined the artifacts and feels that they are Lavallois or older, at least in terms of European experience.

Questions I would like to eddress to you and Ken Frasazier, are: (1) With Dr. Bryan's corroboration, would the Lehi site merit mention in Science News?

(2) Does someone on the Sci ence News staff have a reference fil e on primi t ive skulls in No~thAmerio~ t hat mi ght bear on the Hansen's skull ( see enclos ure 4 ebove-- the skull found :in 1931 on Provo Lake)? (3) Does Ken Frasazierls reference to glaciation Little Cottonwood Canyon (see enclosure #6 above, the second to last paragraph in the last column) come from a paper that is available as, e I'sprint?

Thanking you for your very kind help in this matter, I am , Sincerely yours, Lealand L. Clark, ,M.D.

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LAKE BONNEVILLE'S CYCLES: CLIMATE CLUES (Taken From Science

N9w~,

Vol. lOB)

The Great Salt Lako is the largest lake in the United States wast :~f the Mississippi River, but it is just a . salty drop in the bucket compared with' its en.cient predecessor, Lake Bon~evil1e.

At its maximum, 14,000 years ago~Lake 8onn~vi1le was 13 times 1argei,than the ~resent Great Salt Lake,sprawling over 19,750 square miles , of' northwe\3te,rn Utah and parts of Nevada end Idaho. It was then 1,000 feet highe'r than it is now~ Its waters covered the 'present sHes of most of the large cities of Utah~ It ' rose until its waters spilled over the basin rim at Red Rock Pass in pre~~nt-day southern Idaho, creating a Niagara-eized river flowing into the Columbia :Eih;d wes.tward to the Pacific.

Actually there has been not just one Lake ~'onn~ville but many. Time and time , again this great intermontane lake has expanded and then shrunk , again:. Studies repo~ted rind reviewed at the Geological Society of America annual meeting in Salt Lake City sh9w that the l~ke has gone through far more rise-and~fall cycles than previDuslY , thou~ht~ They also show that thOSQ fluctuations ~rDvide an excellent, and fQr some intsrvals, unsurpassed, record of the vast climate changes in North Americtl .<in"the lest one million yE'lprs. ,

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Times of th~ leks's greatest ' extent c6incide with periods of extensiv~ IDAHO glabiation ih North America, when colder weather 'ce'ucied precipitation to excee·d evapor~tidn. The leke shrinks to i~s m!n'.fmum' levels durin.g werm. interglaCial periods when the higher temperatures cause evaporation to exceed rainfall.

N It wes once thought that ths ancient lake had gone through perhaps four or five cycles of expansion and retreet.

The evidence collected in the last five years clearly reveals no fewer than 28 such cycles in the last 800,000 years.

This lengthens the duration of the climatic record of Lake Bonneville by six times,

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One key piece of evid8nce is a core obtained in 1970 by drilling from the surface to a depth of 307 meters on the LAKE south shore of Great Salt Lake near BurBONNEVILLE mester, Utah. UniverSity of Utah researchers (A. J. Eerdley, et al) have analyzed the upper 110 meters of this UTAH paleomagnetically dated core to produce a detailed record of lake cycles (Goologicel SOCiety of America Bulletin No. 84:211). Roger B. Morrison of the U.S. Geological Survey at Denver calls the Burmester corD "one of the best climatic cores in the world from land."

Tho second line of evidenco is above the surface, exposed stratigraphy at a grElvel pit n82.\1' South Promontory Point, Utah o Morrison considers this expC'su:r.e, which he has studiod extensivoly, an outstanding record, one that surpa8sea any other on the surfece. "It has established many details of lake history that were previously unknown~1I (Continued) !

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LAKE BONNEVILLE'S CYCLES (Continued) In general, deep cores p'rovide a good recoI'd of when lClke writer wes present or Bbsent ,at any lovel end time; sUI'face stratigI'aphy pI'ovldes the 6leerest evidence of maximuM levels ofthe ' l~ka • .

Morrison hes ' prepar~d a chart of lake cycles, which is yet to be published, that shows more than 20 mejor lake cycles in the last 850,000 yoars, ten of them farther beck than 500,000 , years ago~ Included is the cleaI'est picture yet of e group of ·thI'oO strong intoI'glacial peI'iods, with weak glaciel peI'iods, 600,000 to ?OO ~ OOO yeers ago • • "I know of no better recoI'd of this time in North America," seys lYiorrison • . " ,' . .

In more recent times, Morrison's record clearly shows the strong, well-defined

glaci ~ l periods of epproxima~e1y 125,000; 200,DOO; 30b,000; 400,000 and 440,000 years

ago, plus the more recent .

glacl~l.

advances of the last 100,000 years. ,

South of Salt L~ke City in ~ittlo Cottonwood -Canyon geologists have found Intriguing direct proof that the lake t s high l.evels coinoided with times of maximum glac :i.2·t ion. . There ' they have found glacie:c"':depq9it~d rocks interbedded with former lake Ja posits in such a w~y thet the rocks had to h~ve been rolled in wet lake mud.

The g19 ciers virtually licked the edge of the expanded lake. "I know of no other place i~ the world that shows that relationship better,~ says Morrison.

All in all, the sediments along end beneath the shores of the Great Salt Lake are revealing a record of a prehistoric Leke Bonneville th~t h~s gone through many more o!?cillations than previously expected (IIThis surprised many people," says Marriso~ ) ~ nd is Simultaneously proving to be a valuable indicator, nearly akin to deep-sea-core records, of how climate has changed in North America . in the last million yoers.

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APRIL 1975

CHAPTER t\iEWS CHAPTERS HOLD JOINT FIELD TRIP Members of the Lahontan Basin Chapter and the Salt Lake - Davis Chapter joined together in April on a field trip to the Big Blow area near Milford, Utah. The varied artifacts that have been uncovered at the Big Blow by weathering over the years seem to indicate that the area was used as a camp site over a long period of time.

Artifacts found on this field trip were shown to the state archaeologist and a site survey sheet was filed with a description of the findS. Dave Madsen, State Archaeologist, confirmed that some of the artifacts appeared to be quite old.

LAHONTAN BASIN CHAPTER

SALT LAKE - DAVIS CHAPTER

The follow!ng officers were elected to 6erve during 1975: President

Dale Andreason

Secretary

Beverly Andreason

ABOUT THE COVER The petroglyphs on the cover are found in Nine Mile Canyon, an area which has a multitude of important and historic rock drawings~ Rendering by RuJean Rogers Brunson.

COUNTY

av

The State Archaeologist, Dave Madsen, and his assistant, Mike Berry, have been conducting e:eer1os of workshops at th6 past three chapter meetings. Their aim has been to give the members the knowl~ edge to recognize and appreciate the probable age of pottery and arrowheads when they see them. Members have been urged to bring in artifacts in their collections for the purpose of identifying them.

These lectures have been a great bene~ fit to club members.

COUNTY SITE SURVEY BEING CONDUCTED

The Utah state Archaeologist Dave Medsen and his assistant, Mike Berry, are making a county by county survey of archaeological sites in the state of Utah.

They have been checking and correlating all previously recorded site information.

They realize that there are a great many sites of which they have no knowledge which should be included in the survey of each county.

They are urging anyone with knowledge of prehistoric living sites to come to the office of the state Archaeologist and fill out site survey sheets. They have complete maps of all areas of Utah so that the sites can be pinpointed down to township and sectio~. A drawing or description of artifacts, etc. found at the site are wanted as well.

DAve and Mike should have as complete a listing of sites as possible to be of valuo in drawing conclusions as to when areas where inhabited and by what peoples.

Artifact end pottery descriptions will aid in determining time period of occupation a~d probable cultures.

APRIL 1975

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I\..JEW5L t 1 T ER UTAH; STATEWIDE ARCHA~O~OGICAL SOCIETY Editor. RUJOElA:'R. Bt-unson ! â&#x20AC;¢

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1180: (1'91n Avenue ., Salt Lake Citt~ utah . 84106

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