UNIVERSITY OF MINNESOTA REGIONAL HYDROGEOLOGIC ASSESSMENT QUATERNARY GEOLOGY-SOUTHWESTERN MINNESOTA SURFICIAL GEOLOGIC MAP. Carrie J.

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$UNIVERSITY OF MINNESOTA REIONAL HYDROEOLOIC ASSESSMENT QUATERNARY EOLOY-SOUTHWESTERN MINNESOTA SURFICIAL EOLOIC MAP By Carrie J. Pattersn 1994 \br. it (. j V XIJ ) w \" t-tl)'")1\vv N fttlm Or.$

1 UNIVERSITY OF MINNESOTA REIONAL HYDROEOLOIC ASSESSMENT QUATERNARY EOLOY-SOUTHWESTERN MINNESOTA SURFICIAL EOLOIC MAP By Carrie J. Pattersn 1994 \br. it (. j V XIJ ) w \" t-tl)'")1\vv N fttlm Or. \ {( J (7. R t1 (\-"2. I ( OJ' A Minnesta elgical Survey 2642 University Avenue St. Paul, Minnesta (612) Open-File Reprt 94-2 Cntents: Text (includes lcatin diagram, crrelatin and descriptin f map units, and descriptin f map symbls), 5 p. Map (scale 1:200,000), 1 zalid-paper-cpy sheet The text and accmpanying map are preliminary and have nt been reviewed [r cnfrmity with Minnesta elgical Survey editrial standards Funding fr this prject apprved by the Minnesta Legislature, M.L. 91, Ch. 254, Art. 1, Sect. 14, Subd. 4(f), and M.L. 93, Ch. 172, Sect. 14, Subd. l1(g), as recmmended by the Legislative Cmmissin n Minnesta Resurces frm the Minnesta Envirnment and Natural Resurces Trust Fund Prepared with the supprt f the Mi nnesta Department f Natural Resurces, Divisin f Waters The University f Minnesta is an equal pprtunity educatr and emplyer

2 MAP AREA ROO< INDEX MAP OF MINNESOTA SHOWIN LOCATION OF MAP AREA 92 Suthwestern Minnesta-Surficial gelgic map 1 Minn. el. Survey Open-File Reprt 94-2

3 til c: :T I;; c; 3 3: 5 I;; S ::> n : c 8 0' c 3 '0 "' t-.> 3: ;.? (") ;<. til < -g ::l :!1 0" ;0 (") '0 g 'R N Ice Depsits (In places mdified by later surficial prcesses) I I t [ tl I tl I rn I CORRELATION OF MAP UNITS Stream Depsits I Imdl ts d [ d F*1 d sb sbd yd-c I I S ld l EJ Lake Depsits I I , S- Bedrck,L, } Late Wiscnsinan } Wiscnsinan } Pre Wiscnsinan majr uncnfrmity B } Hlcene Pleistcene Early } Prterzic QUATERNARY PROTEROZIC

DESCRIPTION OF MAP UNITS HOLOCENE Organic depsits-includes peat, marshes, and shallw lakes. Typically fund in depressins in hummcky and cllapsed till and alng glacial stream channels.

4 DESCRIPTION OF MAP UNITS HOLOCENE Organic depsits-includes peat, marshes, and shallw lakes. Typically fund in depressins in hummcky and cllapsed till and alng glacial stream channels. Lake sediment-clay, silt, and sme rganic material. These frmer lakes were cmmnly shallw (less than 10 feet deep); sme were drained artificially. PLEISTOCENE Depsits f the Bemis and Yunger Phases f the Des Mines Lbe (Late Wiscnsinan) Till f the Bemis mraine-till with lenses f srted sediment. Matrix texture is lam t clay '-----==---J lam. Yellw-brwn where xidized, gray where unxidized. Cntains pebbles f carbnate, felsic- and mafic-igneus rcks, shale, chert, and sme lignite. Depsited alng frmer ice frnt. The mraine frms prminent ridge in nrthwest part f map area; it becmes brader and thinner in its suthward extent. Inferred frm limited sampling and extraplatin frm adjining areas in Suth Dakta t cntain supraglacial, prglacial, subglacial, and ice-thrust material. Supraglacial till- Hummcky till with discntinuus lenses f clay, silt, sand, and gravel. Matrix texture is lam t clay lam. Till clr and pebble assemblage similar t that f Bemis mraine (unit tbd), thugh till is generally mre deeply xidized. Till was depsited n wasting ice and was subjected t repeated mass mvement during depsitin. Includes small areas f supraglaciallake and stream sediment. Subglacial till-lw-relief depsits f hmgeneus till. Matrix texture is lam t clay lam. Till clr and pebble assemblage similar t that f Bemis mraine (unit tbd), thugh till is generally nt as deeply xidized. Lcally verlain by thin (apprximately 10 feet thick), discntinuus supraglacial and englacial till and srted sediment that typically frm subparallel ridges transverse t and, less cmmnly, parallel t inferred directin f glacial ice flw. Till with stream-mdified surface-till mdified by flwing water; lcally fluvially erded and streamlined. Matrix texture is lam t clay lam. Pebble assemblage and till clr are the 6 same as that f the Bemis mraine till (unit tbd). Lcally verlain by thin lag f sand and gravel r cvered with silt and clay. Channel scars cmmn. Cllapsed unit (ttd-c) was depsited n ice surface, which was subsequently undermined by subglacial water flw, causing cllapse f thinned ice and its verlying depsit; resulting tpgraphy and stratigraphy are chatic and deranged. Till mdified by slpe prcesses-till alng slpe f Cteau des Prairies (a glacial ersinal scarp). Mdified by slpe wash and mass mvement. Matrix texture, clr, and pebble assemblage similar t Bemis mraine till (map unit tbd). Cllapsed unit (tmd-c) was depsited B n ice surface, which was subsequently undermined by subglacial water flw, causing cllapse f thinned ice and its verlying depsit; resulting tpgraphy and stratigraphy are chatic and deranged. Till verlain by thin lake sediment-lw-relief area f till with discntinuus, silty, clayey cap. Temprarily cvered by ice-impunded lake. Includes lw-relief ice-walled-lake plains. Sme areas f rganic accumulatin are t small t shw at map scale. Till texture, clr, and pebble assemblage similar t Bemis mraine till (unit tbd). Stream sediment beynd Bemis mraine-sand and gravel depsited by meltwater that issued frm ice at the Bemis ice psitin. Texture generally becmes prgressively finer- t sand and silt-further up sectin and farther frm frmer ice frnt. Includes sediment f cntempraneus nnglacial tributaries and yunger, pstglacial streams, especially alng mdem stream curses. Dendritic, integrated netwrk f streams takes advantage f lder glacial and nnglacial stream channels, resulting in stream channels f multiple ages and levels. Suthwestern Minnesta-Surficial gelgic map 3 Minn. el. Survey Open-File Reprt 94-2

Stream sediment verlain by till-sand and gravel depsited by subglacial meltwater stream and buried by supraglaciai and englacial till and lake sediment; lcatin inferred frm tpgraphic expressin and

5 Stream sediment verlain by till-sand and gravel depsited by subglacial meltwater stream and buried by supraglaciai and englacial till and lake sediment; lcatin inferred frm tpgraphic expressin and subsurface data; interpreted as tunnel-vahey depsits. Stream sediment behind the Bemis mraine-sand, gravel, and silt depsited by meltwater that issued [rm stagnating r retreating ice behind the Bemis mraine. Includes yunger glacial and pstglacial stream sediment and clluvium. Stream netwrk prly integrated wing t B depsitin alng melting ice frnt, ice cllapse, and lw stream gradient. Cllapsed unit (sd-c) was depsited n ice surface, which was subsequently undermined by subglacial water flw, causing the cllapse f the thinned ice and its verlying depsit; the resulting stream netwrk is in places segmented and chatic and has disrdered depsits. Stream sediment buried by lake sediment-similar t stream sediment behind the Bemis mraine (unit sd) but buried by thin clay, silt, fine sand, and rganic depsits. Streams flwing dwn Cteau des Prairies slpe created fans that caused water t pnd alng nrthwest-sutheast-trending drainage at slpe base. Sediment f ice-walled glacial lakes-lake sediment in high tpgraphic psitin. Depsited in pls in stagnant ice; includes sand and gravel alng frmer lake rims and sand, silt, clayrhythmically layered in places-near frmer lake centers. Cmmnly cntains thick, till-like debris-flw depsits. Frms flat-tpped circular uplands within hummcky till terrain. Chains f lakes cmmnly parallel frmer ice-marginal channels. Depsits Assciated with the Verdi Ice Psitin f the Des Mines Lbe (Wiscnsinan) Till f the Verdi psitin-lw-relief area f erded till. Similar t till f Bemis mraine (map 8 unit tbd). Matrix texture is lam t clay lam. Pebble assemblage and clr similar t unit tbd, thugh till is slightly mre xidized and leached; lcally cvered with thin (abut 5 feet thick) windblwn sediment. Ice margin prbably nly a few thusand years lder than that f Bemis phase. Stream sediment f the Verdi psitin-sand and gravel depsited by meltwater that issued frm ice frnt; sediment depsited by waning water flw and wind is cmmnly siltier. Channels lcally reccupied by Bemis-age and yunger streams. Unit includes sediment f nnglacial tributaries and yunger streams. Stream netwrk dendritic and well integrated. Older lacial Depsits (Pre Wiscnsinan) Till-Very dense till. Frms lw-relief, erded till plain that was dissected by yunger glacial streams. Matrix texture is clay lam t silty clay lam. Yellw brwn where xidized, gray where unxidized. Pebbles include carbnate, felsic- and mafic-igneus rcks, and shale. Lcally verlain by windblwn sediment. lacial stream sediment encuntered in scattered brehles. Till with stream-mdified surface-till mdified by flwing water; lcally fluvially erded. Channel scars cmmn. Texture, clr, and pebble assemblage are the same as till f map unit t. Lcally verlain by thin lag f sand and gravel r filled with silt and clay. Till verlain by windblwn sediment-till f map unit t verlain by mre than 5 feet f windblwn silt, fine sand, and clay. Windblwn sediment verlying stream sediment encuntered in scattered brehles. Till verlain by lake sediment-singular shallw depsit f silt, clay, and rganic depsits verlying till similar t map unit t. The basin, near twn f Jasper, is circular depressin reflecting lcal lw in Siux Quartzite surface; it cntains late-glacial and Hlcene lake sediment. Stream sediment-sand and gravel depsited by meltwater that issued frm lder, incmpletely preserved ice psitin(s). Sme stream channels were repeatedly reccupied by Verdi- and Bemis-age and yunger streams. Mapped in all slpe psitins, including the interfluves f yunger streams. Cmmnly capped with lcally thick silty stream and windblw sediment. Suthwestern Minnesta-Surficial gelgic map 4 Minn. e!. Survey Open-File Reprt 94-2

I... EARLY PROTEROZOIC Siux Quartzite-Expsures and shallwly buried bedrck f Prterzic Siux Quartzite. Extremely indurated, pink, sandstne-dminated quartz arenite f terrestrial fluvial rigin.

6 I... EARLY PROTEROZOIC Siux Quartzite-Expsures and shallwly buried bedrck f Prterzic Siux Quartzite. Extremely indurated, pink, sandstne-dminated quartz arenite f terrestrial fluvial rigin. Has frmed a tpgraphic high since Prterzic time. Lcally glacially streamljned, striated, and wind plished. DESCRIPTION OF MAP SYMBOLS elgic cntact-established frm aerial phtgraphs, gemrphlgy and examinatin f surficial material. Suthwestern Minnesta-Surficial gelgic map 5 Minn. el. Survey Open-File Reprt 94-2

SOIL PROPERTIES STUDY NOTES

SOIL PROPERTIES STUDY NOTES UNIT I SOIL PROPERTIES Objectives and Values f Getechnical Engineering Physical prperties f sil Phase relatins, Grain size distributin, Atterberg Limits, Sil descriptin and