MAP SYMBOLS

Contact, approximately located. Virtually all contacts are mapped from potential-field geophysical data.

Contact, mapped beneath Paleozoic strata.

Dike, mapped beneath Paleozoic strata.

Inferred fault, displacement sense unknown.

Inferred fault, mapped beneath the Sioux Quartzite or Paleozoic strata.

Inferred dip-slip fault; sense of displacement is indicated by U and D onupthrown and downthrown blocks, respectively.

Inferred strike-slip fault; sense of displacement indicated by arrows.

Structural form lines that approximate the general trend of gneissic layering.Lines are generalized from the digital image of the first vertical derivativeof the aeromagnetic field; they are shown only in areas where the geophysicalimage reveals consistent, interpretable patterns.

Strike and dip of principal or most prominent foliation.

Bearing and plunge of principal or most prominent lineation.

Axial surface trace of upright antiform in gneissic rocks; arrow indicates generalsense of axial plunge.

Bedrock outcrop.

Detailed mapping of bedrock outcrop. See the index to previous mapping forregional data sources.

Large area of bedrock near the land surface.

Exploration borehole, scientific borehole, or water well from which core orcuttings of Precambrian bedrock was recovered.

Location of a water well that reached Precambrian bedrock. The logs of thewells contain interpretable descriptions of the bedrock encountered, butno samples are available for verification.

Centroid of felt reports of a minor earthquake on the indicated date.

REFERENCES

Bauer, R.L., 1980, Multiphase deformation in the Granite Falls–Montevideo area, MinnesotaRiver Valley, in Morey, G.B., and Hanson, G.N., eds., Selected studies of Archeangneisses and lower Proterozoic rocks, southern Canadian Shield: Geological Societyof America Special Paper 182, p. 1-17.

Boerboom, T.J., and Holm, D.K., 2000, Paleoproterozoic intrusive igneous rocks ofsoutheastern Stearns County, central Minnesota: Minnesota Geological Survey Reportof Investigations 56, 36 p.

Buchan, K.L., Halls, H.C., and Mortenson, J.K., 1996, Paleomagnetism, U-Pb geochronology,and geochemistry of Marathon dykes, Superior Province, and comparison with theFort Frances swarm: Canadian Journal of Earth Sciences, v. 33, no. 12, p. 1583-1595.

Chandler, V.W., 2002, Superimposed magnetic on gravity anomaly map of southwestMinnesota: Minnesota Geological Survey Miscellaneous Map M-122, scale 1:250,000.

Doe, B.R., and Delevaux, M.H., 1980, Lead-isotope investigations in the MinnesotaRiver Valley—Late-tectonic and posttectonic granites, in Morey, G.B., and Hanson,G.N., eds., Selected studies of Archean gneisses and lower Proterozoic rocks, southernCanadian Shield: Geological Society of America Special Paper 182, p. 105-112.

Goldich, S.S., and Fischer, L.B., 1986, Air-abrasion experiments in U-Pb dating ofzircon: Chemical Geology, v. 58, no. 3, p. 195-215.

Goldich, S.S., Hedge, C.E., and Stern, T.W., 1970, Age of the Morton and MontevideoGneisses and related rocks, southwestern Minnesota: Geological Society of AmericaBulletin, v. 81, no. 12, p. 3671-3695.

Goldich, S.S., Hedge, C.E., Stern, T.W., Wooden, J.L., Bodkin, J.B., and North, R.M.,1980, Archean rocks of the Granite Falls area, southwestern Minnesota, in Morey,G.B., and Hanson, G.N., eds., Selected studies of Archean gneisses and lower Proterozoicrocks, southern Canadian Shield: Geological Society of America Special Paper 182,p. 19-43.

Goldich, S.S., and Wooden, J.L., 1980, Origin of the Morton Gneiss, southwestern Minnesota:Part 3. Geochronology, in Morey, G.B., and Hanson, G.N., eds., Selected studies ofArchean gneisses and lower Proterozoic rocks, southern Canadian Shield: GeologicalSociety of America Special Paper 182, p. 77-94.

Hanson, G.N., and Himmelberg, G.R., 1967, Ages of mafic dikes near Granite Falls,Minnesota: Geological Society of America Bulletin, v. 78, no. 11, p. 1429-1432.

Himmelberg, G.R., 1968, Geology of Precambrian rocks, Granite Falls–Montevideo area,southwestern Minnesota: Minnesota Geological Survey Special Publication SP-5,33 p.

Jirsa, M.A., and Chandler, V.W., 1997, Scientific test drilling and mapping in east-central Minnesota, 1994-1995: Summary of lithologic results: Minnesota GeologicalSurvey Information Circular 42, 105 p.

Jirsa, M.A., Chandler, V.W., Cleland, J.M., and Meints, J.P., 1995, Bedrock geologic mapof east-central Minnesota: Minnesota Geological Survey Open-File Report 95-1, scale1:100,000.

Patterson, C.J., 1999, Quaternary geology—upper Minnesota river basin, Minnesota:Minnesota Geological Survey Regional Hydrogeologic Assessment RHA-4, pt. A, 2pls.

Patterson, C.J., Knaeble, A.R., Setterholm, D.R., and Berg, J.A., 1999, Quaternarystratigraphy, pl. 2 of Patterson, C.J., Quaternary geology—upper Minnesota riverbasin, Minnesota: Minnesota Geological Survey Regional Hydrogeologic AssessmentRHA-4, pt. A, 2 pls.

Setterholm, D.R., 1990, Geologic map of the Late Cretaceous rocks, southwestern Minnesota:Minnesota Geological Survey Miscellaneous Map M-69, 2 pls., scale 1:750,000.

———1995, Quaternary geology—southwestern Minnesota: Minnesota Geological SurveyRegional Hydrogeologic Assessment RHA-2, pt. A.

Southwick, D.L., 1994, Assorted geochronologic studies of Precambrian terranes inMinnesota: A potpourri of timely information, in Southwick, D.L., ed., Shortcontributions to the geology of Minnesota, 1994: Minnesota Geological SurveyReport of Investigations 43, p. 1-19.

Southwick, D.L., and Chandler, V.W., 1996, Block and shear-zone architecture of theMinnesota River Valley subprovince: Implications for Late Archean accretionarytectonics: Canadian Journal of Earth Sciences, v. 33, no. 6, p. 831-847.

Southwick, D.L., and Day, W.C., 1983, Geology and petrology of Proterozoic maficdikes, north-central Minnesota and western Ontario: Canadian Journal of EarthSciences, v. 20, no. 4, p. 622-638.

Southwick, D.L., Setterholm, D.R., Runkel, A.J., Patterson, C.J., and Chandler, V.W.,1993, Scientific test drilling, 1989-1992: Descriptions and interpretations pertinentto the bedrock geology and Quaternary hydrogeology of southwestern Minnesota:Minnesota Geological Survey Information Circular 39, 63 p.

Van Schmus, W.R., MacNeill, L.C., Holm, D.K., and Boerboom, T.J., 2001, New U-Pbages from Minnesota, Michigan, and Wisconsin: Implications for Late Paleoproterozoiccrustal stabilization: Institute on Lake Superior Geology, 47th Annual Meeting,Madison, Wis., Proceedings, v. 47, Program and Abstracts, pt. 1, p. 100-101.

Wirth, K.R., Vervoort, J.D., and Heaman, L.M., 1995, Nd isotopic constraints on mantleand crustal contributions to 2.08 Ga diabase dykes of the southern Superior Province:Proceedings of the 3rd International Dyke Conference, Jerusalem, Program andAbstracts, p. 84.

Yaghubpur, A., 1979, Preliminary geologic appraisal and economic aspects of the Precambrianbasement of Iowa: Iowa City, University of Iowa, Ph.D. dissertation, 294 p., 4 pls.

MISCELLANEOUS MAP SERIESMAP M-121

Pre-Cretaceous Bedrock, Southwest MinnesotaMINNESOTA GEOLOGICAL SURVEYV.W. Chandler, Interim Director

The University of Minnesota is an equal opportunity educatorand employer.

GEOLOGIC MAP OF PRE-CRETACEOUS BEDROCKIN SOUTHWEST MINNESOTA

by

David L. Southwick2002

GIS compilation and cartography byJoyce Meints and Philip Heywood

Edited by Lori Robinson

Every reasonable effort has been made to ensure the accuracy of the factual data on whichthis map interpretation is based; however, the Minnesota Geological Survey does notwarrant or guarantee that there are no errors. Users may wish to verify critical information;sources include both the references listed here and information on file at the offices of theMinnesota Geological Survey in St. Paul. In addition, effort has been made to ensure thatthe interpretation conforms to sound geologic and cartographic principles. No claim is madethat the interpretation shown is rigorously correct, however, and it should not be used to guideengineering-scale decisions without site-specific verification.

©2002 by the Regents of the University of Minnesota

Figure 1. Sketch map showing the distribution ofCretaceous bedrock cover in southwestern Minnesota(modified from Setterholm, 1990; Patterson andothers, 1999).

Figure 2. Tectonic sketch map of Precambrian terranesin southwest Minnesota showing subdivision of theArchean Minnesota River Valley subprovince (white),Paleoproterozoic Penokean Orogen (pink) and SiouxQuartzite (orange), and Mesoproterozoic Midcontinentrift system (brown). Paleozoic and Cretaceous cover isnot shown. Modified from Southwick and others, 1993.

Pzu

�s

�d1 �d2

�d3 �d4

�d5 �d6

�l�gp

�gg�gn

�gd

�hn �hg

�dt �g�gr �gb �hd �ng

A�y

A�b A�m A�i A�f A�v A�p

Alg

Agf Ags Ag

Atg

Amg Agn AmAmo

Ama

Amn

NEOARCHEAN ANDMESOARCHEAN

NEOARCHEAN

NEOARCHEAN AND/OR PALEOPROTEROZOIC

PALEOPROTEROZOIC

PALEOZOIC

CORRELATION OF MAP UNITS

unconformity

unconformity

INDEX TO PREVIOUS MAPPINGM-69 (Setterholm, 1990)

RHA-2 (Setterholm, 1995)

RHA-4 (Patterson, 1999)

Digital base modified from 1990 Census TIGER/Line Filesof U.S. Bureau of the Census (source scale 1:100,000); countyborder files modified from Minnesota Department of Transportationfiles; digital base annotation by Minnesota Geological Survey.

Universal Transverse Mercator Projection, grid zone 151983 North American Datum

DESCRIPTION OF MAP UNITS

PALEOZOIC ROCKS

Pzu Upper Cambrian sandstone and shale—Undifferentiated as to formation,situated along the northwestern margin of the Hollandale embayment.Essentially flat-lying marine strata that unconformably overlie Precambrianrocks. Thickness of the section ranges from less than 10 feet (3 meters)along the northwest margin of the unit to more than 300 feet (91 meters)just east of the map area. Contacts of Precambrian rock units mappedgeophysically beneath the Paleozoic rocks are indicated by dotted linesand the map-unit symbols for these units are in italics.

PALEOPROTEROZOIC ROCKS

�s Sioux Quartzite—Quartzite, hard, vitreous, red to pink, prominently cross-bedded, derived mainly from medium- to coarse-grained quartz sandstone.Thin layers of well-indurated mudstone, siltstone, and fine-grained sandstonerepresent less than 5 percent of the formation. The rocks are gentlywarped and/or tilted; master beds typically dip between 5 and 15 degrees.Faults mapped beneath the Sioux Quartzite are indicated by thick dashedlines.

Diabase dikes—Six groups of dikes are distinguished on the basis of trend,magnetic polarity, relative age, modal and geochemical composition, andpetrographic attributes.

�d1 Reversely polarized, east–northeast to west–northwest trend (azimuth 070-110)—Dikes are deuterically altered Fe-tholeiite in which secondaryamphibole has grown extensively at the expense of primary clinopyroxene.The group includes prominent dikes exposed south of Granite Falls andsouth of Franklin. Two dikes near Granite Falls yield whole-rock K-Ardates of 2080 and 1980 Ma (Hanson and Himmelberg, 1967). A dikenear Franklin is dated at 2067 ± 12 Ma (U-Pb on baddeleyite; M. Schmitz,unpub. data, 1998). Petrographically, geochemically, and geochronologicallythese dikes closely resemble dikes of the Kenora–Kabetogama swarm(Southwick and Day, 1983) sampled north of this map area. See group�d2 below.

�d2 Reversely polarized, northwest trend (azimuth 125-140)—Petrographic andgeochemical attributes are unknown within the map area. Some dikes onthis trend may be coextensive with the Kenora–Kabetogama swarm ofnorthern and northwestern Minnesota and adjoining Canada, which is datedat 2076 ± 5 Ma (U-Pb on baddeleyite; Wirth and others, 1995; Buchanand others, 1996). Other reversed dikes on this trend may be substantiallyyounger.

�d3 East–northeast trend (azimuth 075-085)—Dikes of groups �d3 and �d4 cutPaleoproterozoic plutonic rocks in the eastern and southern parts of themap. Group �d3 is reversely polarized and group �d4 is normally polarized.Their trends and geophysical characteristics are similar to those of olivinetholeiite dikes in the St. Cloud area that cut rocks dated at approximately1775 Ma (Van Schmus and others, 2001). The dikes themselves areundated.

�d5 North–northwest trend (azimuth 000-170)—Dikes of groups �d5 and �d6

are associated with strong, pervasive geophysical anomalies and areinterpreted to be relatively thick. Group �d5 is normally polarized andgroup �d6 is reversely polarized. No petrologic or geochronologic dataare available.

�l Lamprophyre, syenite, hornfels, and skarn—The geophysical anomaly generatedby an inferred intrusion near Garvin, in Lyon County, consists of highgravity and low magnetic signatures. This uncommon combination issuggestive of lamprophyre. Test hole SWG-5 intersected hornblendehornfels, marble, scapolite-vesuvianite skarn, and metasomatic garnet-biotite-calcite veins; these rocks are interpreted to have been producedby contact metamorphism in the roof zone of the lamprophyre intrusion(Southwick and others, 1993).

�gp Gabbro, pyroxenite, hornblende gabbro, and hornblende diorite—Small,pipe-like or plug-like intrusions, some of which are compositionally zoned;zoned bodies may contain minor amounts of granodiorite in addition tothe dominant mafic, ultramafic, and intermediate rock types. Includesthe Cedar Mountain Complex south of Franklin, dated by whole-rock Rb-Sr methods at approximately 1750 Ma (Goldich and others, 1970), andultramafic plugs in the Minnesota River Valley northwest of Franklin.

�gg Granite and granodiorite—Geophysical expression resembles that of the FoleyGranite of east-central Minnesota (Jirsa and Chandler, 1997).

�gn Non-magnetic border phase of granitic plutons cored by unit �gg. Interpretedprovisionally as leucogranite.

�gd Granite and granodiorite—Inferred from geophysical expression to be similarto, or possibly equivalent to the Rockville Granite of the St. Cloud area(Jirsa and others, 1995; Boerboom and Holm, 2000).

�hg Biotite-hornblende granite, monzogranite, and monzodiorite—May includelesser amounts of diorite, tonalite, and mafic rock types. Rock recoveredfrom core hole SQ-5 (102-36-11DDDD) is a mesocratic quartz monzodioritepetrographically similar to the Reformatory Granite at its type localitynear St. Cloud. The rock in SQ-5 yields a discordant U-Pb zircon date of1792 ± 31 Ma (Peterman, as reported in Southwick, 1994).

�hn Magnetic border phase of granitoid plutons cored by unit �hg. Interpretedprovisionally as oxide-rich diorite or gabbro.

�hd Diorite and tonalite—May include lesser amounts of granite, monzogranite,monzodiorite, and gabbro.

�ng Norite and gabbro—Geophysically continuous with rock sampled by coredrilling near Spencer, Iowa (Yaghubpur, 1979).

�g Granite—In the southeast corner of the map beneath Paleozoic strata, it occupiesthe centers of compositionally zoned plutons in which the outer portionsare denser, more magnetic rocks interpreted to be diorite, tonalite, andgabbro. Also forms isolated small plutons including a lensoid mass locatedwest of Garvin. Relationships to granite and granodiorite units �gg and�gr are unknown.

�dt Diorite, tonalite, and gabbro—Relatively magnetic and dense rocks that formthe outer parts of zoned plutons in which the central parts are granite ofunit �g. Similar if not identical rocks are interpreted to form discrete,irregularly shaped plutons of various sizes throughout the map area. Rockswithin some of the discrete plutons may be related to the gabbroic anddioritic rocks of unit �gp.

�gb Gabbro—Fresh, two-pyroxene gabbro that forms discrete, widely scattered,stock-like intrusions. Several intrusions contain centrally located smallbodies of low-density rock; these are mapped provisionally as granite(unit �gr).

�gr Granite—Forms the central parts of small, epizonal intrusions that are mainlygabbro; also forms independent small plugs and lenses. The Section 28granite of Goldich and others (1970), located north of Granite Falls, isassigned provisionally to this map unit. The Section 28 granite yields awhole-rock Pb-Pb age of 1840 ± 50 Ma (Doe and Delevaux, 1980).

NEOARCHEAN AND/OR PALEOPROTEROZOIC ROCKS

A�y Mylonitic rocks—Associated with the Yellow Medicine shear zone.

A�b Biotite schist—In part mylonitic, located within and near the Yellow Medicineshear zone.

A�m Felsic metavolcanic rocks and their metaclastic equivalents—Presence inferredfrom geophysical expression.

A�i Mafic to intermediate metavolcanic rocks.

A�f Iron-formation—Oxide-facies iron-formation mapped aeromagnetically andverified by very sparse drilling. Exploration hole E-1, drilled by NewJersey Zinc near Hendricks in Lincoln County, cut iron-formation thatpossesses oolitic to pelletoidal texture, and on that basis is inferred to beof Paleoproterozoic age.

A�v Mafic volcanic and volcaniclastic rocks—Deformed and metamorphosed underconditions of the upper greenschist to amphibolite facies. Includes pillowedmetabasalt and mafic breccia that crop out north of St. Leo in YellowMedicine County.

A�p Peridotite and related ultramafic rocks—Variably metamorphosed toserpentinite, talc-actinolite schist, and essentially monomineralic actinoliterock.

NEOARCHEAN ROCKS

Alg Leucogranite—In part mylonitic, located within and near the Yellow Medicineshear zone.

Ag Granite—Mapped exclusively from geophysical expression. Much of thisunit is probably the same age as the Sacred Heart granite (Ags) or theFort Ridgely granite (Agf).

Agf Fort Ridgely granite—Granite, biotite-bearing, massive to weakly foliated,medium- to coarse-grained, pink to gray.

Ags Sacred Heart granite—Granite, biotite-bearing, medium-grained, pink to gray.Rock is massive except near contacts with wall rocks where it is moderatelyfoliated and locally gneissic. Yields a discordant whole-rock Pb-Pb ageof 2605 ± 6 Ma (Doe and Delevaux, 1980).

Atg Tonalite and granodiorite, undivided—Forms large, poorly defined intrusivemasses toward the eastern edge of the map area and in the west-centralarea west and north of Russell. The eastern mass is mostly beneathPaleozoic strata. Moderately foliated biotite-hornblende tonalite from corehole SQ-8 (Watonwan County, 107-31-11BCCC) yields a discordant U-Pbzircon date of 2624 ± 57 Ma (Van Schmus, reported in Southwick, 1994).

NEOARCHEAN AND MESOARCHEAN ROCKS

Agn Granitic to tonalitic gneiss of the Jeffers block—Drill samples include diversequartzofeldspathic gneisses that are lithologically similar to gneisses ofthe Morton and Montevideo blocks (Fig. 2; Southwick and Chandler,1996); however, temporal and genetic relationships to the Morton andMontevideo Gneisses (units Am and Amo, respectively) have not beenestablished.

Amg Mafic gneiss of the Jeffers block—Inferred from geophysical expression.

Am Morton Gneiss—Gneiss complex composed of several intermingled rock typesof generally quartzofeldspathic composition. The most voluminous variantsexposed along the Minnesota River are: 1. Homogeneous, medium- tocoarse-grained biotite tonalite gneiss that contains scattered inclusions ofamphibolite; 2. Strongly layered tonalite gneiss (layers centimeters todecimeters in thickness) that contains conformable sheets and disconformableblocks of amphibolite; 3. Homogeneous, coarse-grained to pegmatiticgranodiorite gneiss; 4. Massive, fine- to medium-grained granoblasticleucogneiss of granodiorite and tonalite composition; and 5. Anatecticgranite. Rock types 1 through 4 are shades of gray; rock type 5 is pink."Rainbow granite" building stone, quarried at Morton, is a somewhatlocal variant in which the pink anatectic phase is uncommonly abundant.The principal gneissic layering in the Morton Gneiss is subhorizontal andfolded into broad warps that plunge gently to the northeast.Geochronologically, the Morton Gneiss yields published dates that rangebetween 3624 ± 46 Ma on rock type 1 (discordant U-Pb zircon determination;Goldich and Fischer, 1986) and 3043 ± ? Ma on rock type 5 (whole-rockPb-Pb determination; Goldich and Wooden, 1980). See Goldich andWooden (1980) for detailed interpretations of the geochronologic data.

Amo Montevideo Gneiss—Gneiss complex composed of diverse quartzofeldspathicrock types of probable intrusive origin and interstratified mafic andaluminous rock types of probable supracrustal origin, at least in part.Mapped as unit Amo where undivided. The most abundant quartzofeldspathicvariant is a medium-grained, biotite-bearing, streakily layered gray togray-pink gneiss of generally granodioritic composition; this rock typeyields dates as old as 3680 ± 70 Ma (whole-rock Rb-Sr determination;Goldich and others, 1980). Gneiss varieties mapped separately in thevicinity of Granite Falls (after Himmelberg, 1968) are hornblende-pyroxenegranulite and amphibolite of basaltic composition (unit Ama), and biotite-garnet gneiss of broadly graywacke-like composition (unit Amn). Theprincipal gneissic layering in all components of the Montevideo Gneissforms low-amplitude folds that plunge gently to the northeast. Earlierminor folds of several generations are reoriented by the regional broadwarps. See Bauer (1980) and Goldich and others (1980) for detailedinterpretations of structure, geochemistry, and geochronology.

INTRODUCTION

This map shows the configuration of map units of Precambrian (Paleoproterozoic and Archean) and Paleozoicage. The outlines of individual Precambrian units are defined largely on the basis of gravity and high-resolutionaeromagnetic data (Chandler, 2002). This map differs from a conventional "first pre-Quaternary" bedrock geologicmap in that it does not show the distribution of the comparatively thin, horizontally bedded, Cretaceous shale andsiltstone that are widely but discontinuously present above the Precambrian and Paleozoic rocks (Fig. 1).

Many Precambrian rock units depicted on this map on the basis of geophysical expression are assigned Archeanor Paleoproterozoic age designations even though they have not been dated radiometrically, or in some cases evensampled. These speculative age assignments are based on either the geophysical continuity of the map unit with adated rock unit outside the map area, or the similarity of geophysical expression of the map unit to that of a datedrock unit elsewhere. Such age assignments should be viewed as hypothetical, subject to geochronologic verification.

This map was compiled and digitized at 1:250,000-scale. Therefore, no gain in the accuracy, precision, orresolution of the map will result from enlargement.

SUPPORTED IN PART BY THE MINNESOTA LEGISLATURE ON RECOMMENDATIONOF THE LEGISLATIVE COMMISSION ON MINNESOTA RESOURCES

96° 95° 94°

44°

45° M-121 map area

Cretaceousbedrock cover

96° 95° 94°

44°

45°

SiouxQuartzite

Morton block

Benson

Jeffersblock

Montevideo block

Penokean

Orogen

YELLOW MEDICINE SHEAR ZONE

block

Midcontinent rift

M-121 map areaAPPLETON GEOPHYSICAL LINEAMENT

TODD

STEARNS

MORRISON

WR

IGH

T

SIBLEY

NICOLLET

BE

NT

ON

BROWN

BLUEEARTH

FAR

IBA

ULT

94°96°

46°

44°

RHA-4

MARTIN

WATONWAN

MCLEOD

MEEKERKA

ND

IYO

HI

GRANT DOUGLAS

TRAVERSE

BIG STONESTEVENS POPE

CHIPPEWA

YELLOW MEDICINE

SWIFT

LAC QUIPARLE

LYON

MURRAY

ROCK NOBLES

PIP

ES

TO

NE

RENVILLE

REDWOOD

COTTONWOOD

JACKSON

RHA-2

M-69

LIN

CO

LN

45°

95°IOWA

SOU

TH

DA

KO

TA

M-121 map area

Benton

the Hills

AshLake

Beaver Creek

Luverne

Okabena

Chandler

Butterfield

Lake

Lincoln

Lake

Yellow Medicine

Sibley

Minnesota

Granite Falls

Canby

Chippewa

Lac qui Parle

212

23

59

23

23

75

67 67

212

7

59

75 68

271

68

212212

59

29

7

1967

19

67

60

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90

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75

3030

75

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14

90

59

R 46 W R 44 W R 42 W R 40 W R 38 W R 37 W

T 109 N

T 110 N

T 111 N

T 107 N

T 108 N

T 106 N

T 105 N

T 104 N

T 103 N

T 102 N

T 101 N

R 41 W R 39 WR 43 WR 45 W

R 46 W R 44 WR 45 W R 43 W R 39 W

R 36 W R 35 W R 34 W R 33 W R 32 W R 31 W

R 36 W R 35 W R 34 W R 33 W R 32 W R 31 WR 38 W R 37 WR 40 WR 41 WR 42 W

T 112 N

T 113 N

T 114 N

T 115 N

T 116 N

T 117 N

T 118 N

T 117 N

T 118 N

T 116 N

T 115 N

T 114 N

T 113 N

T 111 N

T 112 N

T 110 N

T 108 N

T 109 N

T 107 N

T 106 N

T 104 N

T 105 N

T 103 N

T 102 N

T 101 N

Hazel Run

Maynard

Clarkfield

Cottonwood

Boyd

Minneota

Clara City

Dawson

WoodLake

Montevideo

Sacred Heart

Hendricks

Echo

Belview

Vesta

HanleyFalls

Ghent

Taunton

Porter

Sham

LouieLake

SpellmanLake

Lake

CottonwoodLake

Lady SlipperLake

HendricksLake

LakeTyson

Curtis

LakeWood

Falls

School Grove

PerchLake

SteepBankLake

Lake

Yellow

Branc

h

South

M

edicine

River

SpringCreek

Yellow

Medicine

River

Lac qui Parle

Minnesota

River

Creek

Mud

YellowMedicin

e

River

Lac q

ui

Parle

Riv

er

Lazarus

Creek

ChetambaCreek

Haw

k

Creek C

reek

Sac

red

Hea

rt

Renville

MeekerKandiyohi

Nicollet

Brown

Watonwan

Martin

Lyon

Redwood

Murray

Pipestone

Nobles

Jackson

Slayton

Iona

Avoca

HadleyLake Wilson

Woodstock

Edgerton

Holland

Pipestone

Magnolia

Hills

Ellsworth

Bigelow

HeronLake

Dundee

Fulda

Wilmont

Lismore

Lake

Russell

Lynd

MilroyLucan

Wabasso

Steen

Trosky

Kinbrae

Brewster

Revere Lamberton

WalnutGrove

Westbrook

Currie

Tracy

Seaforth

Arco

Ivanhoe

Tyler

Ruthton

FlorenceBalaton

Garvin

Hatfield

Ihlen

Kenneth

Adrian Rushmore

Round Lake

Dovray

Verdi

Marshall

Worthington

Heron

LakeShetek

SarahLake

Lake

SouthTwinLake

FremontL.

LakeLong

HeronLake

Lake

Talcot

Lake

IllinoisL.

OkabenaLake

Fox Lake

BloodyL.

Goose

LakeStay

IslandLake

LakeWood

OchedaLake

AugustaLake

YanktonLake

RoundLake

WestGrahamLake

LakeOaks

Lime L.

CurrantLake

Lake of

LakeBenton

Shaokatan

RockLake

LakeMarshall

MariaLake

LouisaLake

Jack L.

95°45' 95°30'96°15' 96°00'

43°45'

44°00'

44°15'

44°30'44°30'

44°15'

44°00'

43°45'

95°15' 95°00' 94°45' 94°30'43°30'

95°00' 94°45'95°15'95°30'95°45'96°00'96°15'

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96°30'

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45°00'94°30'

44°45'

96°30'45°00'

Blomkest Lake Lillian

Prinsburg

Cedar MillsCosmos

Danube

Renville

OliviaBird Island

HectorBuffalo Lake

Delhi

North RedwoodMorton

Redwood FallsGibbon

Franklin

Fairfax

Morgan

Clements

Evan

Wanda

Springfield

Sanborn

Comfrey

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