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Baxter Layout PREPARED WITH THE SUPPORT OF THE U.S. GEOLOGICAL SURVEY AS PART OF THE MISCELLANEOUS MAP SERIES 2000 STATE GEOLOGIC MAPPING PROGRAM ELEMENT (STATEMAP) OF THE NATIONAL GEOLOGIC MAPPING PROGRAM MAP M-111 Baxter Quadrangle MINNESOTA GEOLOGICAL SURVEY D.L. Southwick, Director ro pe rls pe ro al pe ri ce pe pe CORRELATION OF MAP UNITS pe Fluvial Lacustrine Glacial Eolian ri Paludal rtm pe pe al rtm ce Holocene ri al pe cwlt mlt rls pe ce ro ro pe cwut QUATERNARY ce ri Late pe ro Pleistocene rls Wisconsinan ro pe ro rls rtm pe ri rt ro ce p pe ce DESCRIPTION OF MAP UNITS MAP SYMBOLS pe This map shows the surface distribution of Quaternary sediments in the Baxter quadrangle. Geologic contact—Approximately located. Established from aerial photo- cwut pe It was constructed in part using aerial photographs taken in 1977 (1:80,000 scale), U.S. graphs, geomorphology, soil maps, well logs, borings, and examination ro pe Soil Conservation Service soil-survey maps for Cass, Crow Wing, and Morrison Counties of surficial materials. RL pe ce pe (Arneman and others, 1965; Brug and Gorton, 1994; Richardson and others, 1997), and Kame—Conical hill composed predominantly of sand and gravel. Interpreted ce information from borings made by the U.S. Geological Survey, Minnesota Department of to be a deposit within the confines of supporting ice. When ice melted, Natural Resources, and Minnesota Geological Survey (Southwick and others, 1986). Field gravel and sand assumed angle of repose. Collapsed bedding is common. work was conducted during the summer and fall of 2000 and included observations, Drumlin—Arrow shows inferred direction of ice movement. Streamlined descriptions, and sampling from shallow auger borings (depth less than 20 feet or 6.1 meters), hill or ridge composed typically of glacial till; formed at the base of moving rls rls roadcuts, outcrops, and construction exposures. Additional information from previous nearby ce Rainy-lobe ice. In the Baxter quadrangle drumlins are commonly covered rls mapping projects was used for interpretation (Mooers, 1988; Schneider, 1961; Goldstein, pe by a thin layer of eolian sand. pe 1985). Esker—Chevrons point in direction of transport. Sinuous narrow ridge of pe pe Holocene predominantly sand and gravel; interpreted as having been deposited in ice-tunnel or ice-walled channels by glacial meltwater streams of Rainy- al Floodplain alluvium—River-channel, overbank, and slackwater deposits of the cwut lobe origin. The fluvial sediment may be covered by as much as 10 feet pe Gull, Crow Wing and Mississippi Rivers composed of gravel, sand, and silt. (3 meters) of till. ce Migrating-channel features are indicated schematically on the map by scroll- cwut rls pe bar symbols. Contains organic debris both disseminated in the sediments Scroll bars—Indicates migration of river channel; surface composed mainly and forming discrete beds. of sand; may be slightly elevated. Symbol is schematic representation; pe Organic deposits—Shallow-water and ponded sediment consisting of peat and individual bars are not mapped. cwut pe other organic-rich materials; may include sandy beach sediments where Stream-cut scarp—Ticks point down scarp; where paired, they indicate former pe surrounding lakes. Typically found in depressions; some deposits have been drainageway. Established from aerial photographs and topographic maps. drained. The depressions are interpreted to have formed along former glacial General flow direction of stream that deposited surficial sand and gravel— stream channels and from melting of buried glacial ice. Arrowhead points downstream. cwut ri cwlt Lower terrace alluvial deposits of the Crow Wing River—River-channel fluvial sand and gravel (about 10–15 percent carbonate rock where not leached, and Broad irregular trough—Ticks point downslope. Interpreted to be buried ce pe rls only a trace amount—less than one percent—of northeastern-source red subglacial drainage channel (tunnel valley) or buried pre-existing subaerial ri rls volcanic-rock and sandstone fragments); fine sand, silt and organic slackwater valley. ce sediments of the Crow Wing River are preserved in a terrace above the modern RL ce Recessional ice margin of the Rainy lobe—Label (RL) on up-ice side. floodplain. South of the confluence of the Crow Wing and Mississippi Rivers Stillstand of the Rainy lobe where distinct ice-marginal landforms formed, al the deposits are interpreted to be composed predominantly of Crow Wing including moraines, tunnel-valley fans, and ice-contact deposits. River sediment. Eolian sand—Pattern indicates wind-blown sand as thick as 10 feet (3 meters) pe mlt Lower terrace alluvial deposits of the Mississippi River—River-channel fluvial cwut R on top of of other mapped sediment types. Sand is irregular in thickness L pe pe sand and gravel (trace amounts of carbonate and about 5–10 percent red ri ce and patchy in distribution in the southeastern part of the map. Although mlt volcanic-rock and sandstone fragments); fine sand, silt, and organic slackwater ce eolian sand may be present on lacustrine deposits (map unit rls) in the ri sediments of the Mississippi River form a terrace above the modern floodplain. ce eastern part of the quadrangle, it is not shown there because both sediments cwut ce mlt Pleistocene are composed of fine- to medium-grained sand and are difficult to pe ce distinguish. pe Collapsed and stream-eroded surface sediment—Fluvial sand and gravel rls containing trace amounts of carbonate and about 5–10 percent red volcanic- Eolian sand dunes—Fine to medium sand forming dunes in the northeast cwut pe ri rock and sandstone fragments; fine sand, silt, and organic sediments are found corner of the map on lacustrine (map unit rls) and organic (map unit pe) mlt ce along the Mississippi and Gull River valleys. The Mississippi River valley deposits. ce encompasses sediment from the top of the incised valley to its lower terrace. Deep boring—Borings greater than 90 feet (27.4 meters) deep by the U.S. mlt ri pe The collapsed terrain adjacent to the Gull River reflects later erosion and Geological Survey and Minnesota Department of Transportation. pe pe deposition along the main Gull River channel and diversion channels. The unit is interpreted to have formed when meltwater (possibly from ice of the Shallow auger boring—Auger borings described, sampled and completed cwut by the Minnesota Geological Survey. They vary in depth from 3 feet (0.9 pe ce St. Louis sublobe northeast of the study area) drained through ice-collapse cwut terrain that developed in former tunnel-valley channels of the Rainy lobe meters) to 25 feet (7.6 meters)—average depth is 18 feet (5.5 meters). cwut pe mlt (Wright, 1972), eroding older materials (including map unit ) and Field observation—Exposures examined and described during field work. depositing a veneer of sediment. ce Material sample—Samples collected during field work. cwut ri cwut Upper terrace (valley train) deposits of the Crow Wing River—River-channel Record of water-well construction—Location of a water well for which there cwut ri fluvial sand and gravel (where unleached, about 10–15 percent carbonate- ce rock fragments and trace amounts—less than one percent—of northeastern- is a log prepared by a well driller. A geologist (either the author or a al cwut rls mlt al source red volcanic-rock and sandstone fragments); also fine sand and silt predecessor) has interpreted the information in the log and verified the cwlt mlt sediments of the Crow Wing River. The Mississippi River also contributed well location. sediment to the unit from Hardy Lake and southward, but the contribution rls al cwut was minor compared to the large volume of Crow Wing River meltwater SELECTED BIBLIOGRAPHY ce mlt sediment that dominates these deposits. The unit is interpreted to have formed Arneman, H.F., Hanson, L.D., Hermanson, H.P., and Hilde, D., 1965, Soil survey of Crow as Des Moines–lobe meltwater drained east through Pillager gap (a mile-wide Wing County, Minnesota: U.S. Soil Conservation Service, scale 1: 20,000; W94°23'39"– cwut gap in the St. Croix moraine about two miles west of the quadrangle along 93°46'32"/N46°48'21"–46°09’23" (printed diagrams, 56 numbered, fold-out diagrams cwlt the Crow Wing River), eroding a wide valley. As water volume decreased, pe bound with text). sediment refilled the scoured valley to the present level. Brug, W.H., and Gorton, J.F., 1994, Soil survey of Morrison County, Minnesota: U.S. Deposits of the Rainy lobe—Glacial till, outwash, and ice-contact sediments Soil Conservation Service, scale 1: 20,000, W94°38'31"–93°45'45"/N46°20'39"–45°46'29" cwut rt deposited by ice of the northeastern-source Rainy lobe (Wright, 1972). (printed diagrams, 71 numbered, fold-out diagrams bound with text). al pe Deposits are commonly deeply leached of carbonate materials and contain Goldstein, B.S., 1986, Stratigraphy, sedimentology, and Late-Quaternary history of the cwlt mlt less than 5 percent carbonate where unleached. Red sandstone and volcanic Wadena drumlin region, central Minnesota: Minneaplis, University of Minnesota, Ph.D cwut cwut pe rock fragments commonly compose 5–10 percent of the coarse materials. dissertation, 216 p. rls Lacustrine deposits of Glacial Lake Brainerd—Well-sorted fine- to medium- Mooers, H.D., 1988, Quaternary history and ice dynamics of the St. Croix phase of Late pe grained noncalcareous sand. At depths greater than 10 feet (3.0 meters) Wisconsin glaciation, central Minnesota: Minneapolis, University of Minnesota, Ph.D. pe cwut cwlt ro sediment may contain interbedded fine sand, silt, and clay layers. Deposited dissertation, 205 p. on and around buried ice blocks left by the Rainy lobe. The ice-blocks melted ———1990, A glacial-process model—the role of spatial and temporal variations in glacier cwut RL ro following drainage of Glacial Lake Brainerd (Mooers, 1988), leaving thermal regime: Geological Society of America Bulletin, v.
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