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Surficial Geology Prepared and Published with the Support of COUNTY ATLAS SERIES ATLAS C-46, PART A MINNESOTA GEOLOGICAL SURVEY THE KANDIYOHI COUNTY BOARD OF COMMISSIONERS AND Harvey Thorleifson, Director THE MINNESOTA ENVIRONMENT AND NATURAL RESOURCES TRUST FUND Kandiyohi County AS RECOMMENDED BY THE LEGISLATIVE-CITIZEN COMMISSION ON MINNESOTA RESOURCES Plate 3—Surficial Geology STEARNS COUNTY POPE 95° 15' W. POPE 95° 7' 30" W. 94° 52' 30" W. COUNTY 95° W. R. 36 W. COUNTY R. 35 W. R. 34 W. R. 33 W. SWIFT Crook 400 nt 360 o Lake ncg pe COUNTY 380 6 ncg 400 o 1 hwt Brenner o o 1 6 1 6 380 380 o 6 )55 Regal ? 1 380 Lake North )4 o ncl al 400 380 Fork nt nco Section ? o o nct pe CORRELATION OF MAP UNITS 400 Twelve ? Crow SURFICIAL GEOLOGY Lake 380 ? Middle o nuo Lake pe nuo Villard Ole ncg 380 complex Ice River Hefta o deposits deposits Lake 380 Hystad o 380 360 By NORWAY LAKE Lake COLFAX Fork BURBANK ROSEVILLE 45° 22' 30" N. pe 380 Crow nuo 45° 22' 30" N. 380 o 380 al pe hl Holocene Blaamyhre ? o o A' T. 122 N. 380 380 Lake T. 122 N. o o Amie E. Staley 380 o o pe A 380 River LOCATION DIAGRAM 380 nls nht Heiberg Member nt Glesne nct Reamer nuo o ncl 380 Lake 400 380 Lake ncg 380 o ncl New Ulm QUATERNARY 2019 380 380 hl 380 380 Formation Wisconsinan 380 380 380 )23 380 380 ncg nt Villard Member Episode )9 o o 380 380 nct 380 o nco o 380 380 400 ¤71 nct o 380 380 nct o ? o Sunburg o 380 380 Hewitt o Lake o o 380 hwt Formation o 380 Monongalia Lake 36 31 36 31 36 31 Otter Lake Ko Games Lake Swan ronis Creek STEARNS 31 380 380 Lake 360 36 Lake o pe COUNTY o 360 380 400 o o 6 o380 Knutsons ncg o 380 o o )9 o Long nct MEEKER INTRODUCTION in southwestern Kandiyohi County, suggesting wave action eroded near-shore sediment, or that lake incorporated from the Hewitt Formation. Land-surface expressions of these deposits are nco Lake 1 o 380 Henschien o o Lak380e COUNTY 6 hl 1 6 ncg 1 sediment was partially supported by ice that later melted and collapsed. Other small, localized lakes generally irregular and hummocky, and include circular, flat-topped hills interpreted to Lake nct 1 6 This map characterizes the origin and distribution of the surficial geologic materials in Kandiyohi East 380 likely formed contemporaneously with glacial Lake Benson as ice blocks continued to melt throughout be ice-walled lake plains; elongate, sinuous ridges parallel to ice flow, interpreted to be Sunburg o 380 380 County, Minnesota. Map unit delineation and landform distribution were based on 1-meter resolution lidar Lake Norway Lake o nco the region, depositing silt, sand, and clay (unit nls). eskers (subglacially formed); or sinuous ridges parallel to the ice margin, interpreted to Middle Lake Andrew Lake Bear Lake elevation imagery (available from the Minnesota Department of Natural Resources <http://www.mngeo. ncg )23 be ice-disintegration ridges (supraglacially formed); large, pitted mounds interpreted to New Sh400oemaker nht nct state.mn.us/chouse/elevation/lidar.html>), a 10-meter digital elevation model that includes bathymetric 380 London Lake 360 POST GLACIAL HISTORY be tunnel-valley kames; and ice-marginal ridges that consist of mostly till. Lake 380 pe nt Eight B' data for some lakes (Fig. 1), Kandiyohi County soil survey map (Natural Resources Conservation Services, pe ncl Silt and clay—Stratified to massive silt and clay deposited in localized depressions between 380 400 2014), and previous studies (refer to Index to Previous Mapping). Further interpretations were drawn Once Minnesota became ice-free by the beginning of the Holocene Epoch, glacial meltwater was pe the Des Moines lobe and Bonanza Valley sublobe. Generally a positive feature in the B 380 380 nt 380 from well logs included in the Minnesota Geological Survey County Well Index (CWI) and Quaternary reduced and modern alluvial channels and floodplains (unit al) began to form. Lakes continued to landscape where small, ice-walled lakes collapsed when ice melted. Glaciolacustrine 380 380 Data Index (QDI—an internal working database of the Minnesota Geological Survey), including bridge accumulate organic matter and fine-grained sand and silt (unit hl). Peat (unit pe) also accumulated in complex deposit. Creek Cedar Island 400 nco borings and gravel pit data from the Minnesota Department of Transportation (2015), and U.S. Geological depressions created during glaciofluvial scouring and ice-block melt-out. No significant evidence for 380peARCTANDER nco LAKE ANDREW Lake 380 360 IRVING Sand to loamy sand and gravel—Stratified to massive sand and gravel transported and T. 121 N. 380 NEW LONDON T. 121 N. Survey scientific test holes. Field work conducted during 2016 and 2017 expanded unit interpretations eolian sediment (loess) was identified in Kandiyohi County, but sand dunes in adjacent Meeker County to ncg 360 deposited in the interlobate depression between the Des Moines lobe and Bonanza Mary Shakopee and included detailed descriptions and sample extraction from exposures in gravel pits, road cuts, the east are interpreted to represent a warm, dry period after 8,000 years (Meyer, 2015). Lake sediment 380 nct nls Lake nt and pollen assemblages from Lake Ann, Sherburne County (to the northeast), suggest that this warm, Valley sublobe, generally forming esker, ice-disintegration ridge, or tunnel-valley kame 360 construction sites, and other excavations. In addition, 103 auger borings, drilled to an average depth of Swenson 360 Lake Calhoun 360 20 feet (6 meters), were described and sampled throughout the county, and four rotary-sonic drill cores dry period lasted until about 5,000 years ago (Keen and Shane, 1990), when conditions began to change topography. The upper section of the unit may be leached of carbonate in some locations. Lake nco Glaciofluvial complex deposits. 380 nht were acquired from depths of 270 to 450 feet (82 to 137 meters). Approximately 268 surface samples towards the modern-day climate. Beach sediment is not mapped in Kandiyohi County, but may exist 380 hl Henjum Lake Norstedt 380 nt (upper 10 feet [3 meters]) were analyzed for grain-size distribution, lithology of the very coarse-grained as a thin rim of reworked till or outwash on typically the eastern edges of lakes. Thickness of beach nct Sandy loam to loam diamicton—Unsorted sediment with a coarse-grained loam matrix 360 Lake 380 380 nuo (1-2 millimeter) sand fraction, and Munsell color. All analytical results were digitized and compiled sediment is dependent upon lake levels, which vary seasonally or yearly. Anthropogenic influence has containing uncommon to common pebbles and rare cobbles and boulders; generally 380 Nest Lake 360 pe geospatially for mapping. The Surficial Geology map depicts the natural surface materials found in altered the landscape in some locations, especially in more populated and developed areas, such as the light olive-brown (2.5Y 5/4) where oxidized and dark gray (5Y 4/1) where unoxidized. Lake Florida 360 pe Kandiyohi County beneath the soil horizon and does not include anthropogenically modified material. city of Willmar. Average composition of the very coarse-grained sand fraction (Table 2) is characterized 45° 15' N. Cro360ok Green Lake Lake 360 45° 15' N. by a low percentage of gray shale fragments (14 percent). Villard Member till complex 31 36 nt C' 31 31 360 36 ACKNOWLEDGEMENTS deposits. 36 George 360 GLACIAL HISTORY nco 31 Jessie Lake Lake nuo Villard Member C 360 The unique continental position of Minnesota, located at approximately 45° north of the equator, Emily Bauer, Sonia Ellison, Matthew Ettsen, Ryan Puzel, Anik Regan, Shawn Scott, and Zachery 360 Woodcock Lake 360 Carlson 6 Sandy-loam to loam diamicton—Unsorted sediment with a coarse-grained loam matrix 360 6 360 provided the ideal climate for advancing and receding ice lobes of the Laurentide Ice Sheet during the Van Orsdel of the Minnesota Geological Survey assisted with drilling on this project. Thanks to all nt 1 Lake 1 6 Lake Ringo Henderson 1 containing uncommon to common pebbles and rare cobbles and boulders; includes areas 360 nco 1 Spicer 6 Pleistocene Epoch (2.6 million to 11,700 years ago). Ice lobes from various northern provenances of the landowners who allowed rotary-sonic drilling on their property, and to all gravel pit owners and nco pe Florida Lake Lake Carlson operators and landowners who gave permission to examine exposures on their property. Traut Drilling of sand and gravel that are too small to be mapped; generally light olive-brown (2.5Y 5/4) 340 Slough advanced over diverse bedrock types and deposited thick packages of texturally and lithologically nco Lake East 360 distinct material in Minnesota (Fig. 2; Table 1). The most recent glacial event in this area, known as the Company conducted the rotary-sonic drilling. where oxidized and dark gray (5Y 4/1) where unoxidized. Average composition of the Twin East 360 Alvig Woodcock nht Wisconsinan Glacial Episode, lasted from about 110,000 years ago to the start of the Holocene Epoch, very coarse-grained sand fraction (Table 2) is characterized by a low percentage of gray Mamre West Lake Swan Twin Slough Lake shale fragments (14 percent). Unit is generally at the surface in the central and northern Lake nt nt 11,700 years ago. The Holocene Epoch marks the end of the last glacial period in Minnesota and the DESCRIPTION OF MAP UNITS Lake Lake Elkhorn nt parts of the county, on the Alexandria moraine.
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