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Geology of Van Buren County
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This information was taken from the Soil Survey of Van Buren County.
The landscape of Van Buren County was formed by the complex action of the Lake Michigan Lobe of the Wisconsin glacial ice sheet. The glacial action resulted in five dominant features ? moraines, till plains, outwash plains, lake plains and drainage ways and areas where muck and silt were deposited by ponded water on till plains. Some areas of the moraines and till plains were modified by windblown sand and some areas of the till plains were modified by shallow water.
Click to see maps of Bedrock Geology and Surface Geology in Van Buren County
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Moraines
Plains
Other Geological Features
Bedrock Geology in Southwest Michigan
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Moraines
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Three major moraines traverse the county in a generally northeast-southwest direction. The Kalamazoo moraine system is in the southeast corner of the county. It is spotted with outwash plains. The Valparaiso moraine system makes up a large part of the county. One very broad ridge is in the southern part of the county and three ridges are in the northern part. Also part of the Valparaiso system are numerous outlying moraines on the till plain in the western part of the county. The Lake Border moraine system in Van Buren County occurs only as one narrow ridge roughly paralleling the shore of Lake Michigan. The ridge is 1.5 to 4 miles inland.
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Related Links:
Geology - MSU
Geology - WMU
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Plains
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Till Plains
The till plains are fairly well scattered throughout the county. A bank of till 2 to 4 miles wide is between Bloomingdale and Gobles, starting about 1 mile south of the Allegan County line and ending about 2 miles southeast of Glendale. A large till plain modified by shallow water is in the area west of a line from Lacota to near Hartford. A narrow band of till is directly west of the Lake Border moraine. Many small till plains are throughout the county.
Outwash Plains
The outwash plains are mainly in the southeastern part of the county. The largest one is between Keeler and Decatur running from the Cass County line northeastward to an area near the Paw Paw River between Lawrence and Paw Paw. The other outwash areas are smaller and are on the eastern side of the moraines.
Lake Plains
The lake plain areas include a band of material directly east of the sand dunes along Lake Michigan, the western half of Geneva Township and an area near Grand Junction that was part of a glacial lake. The drainage ways are those along the Paw Paw River and the Dowagiac River and the drainage way north of Mentha.
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Other Geological Features
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There are two areas of the county that were affected by ponded water rather than glacial lakes. One area includes most of the southeast corner of Columbia Township and most of the northeast corner of Arlington Township. The other is a much smaller area around Kendall, in Pine Grove Township.
Other features include kames, sand dunes, a few large boulders left by the glacier and in gravel pits, beds of ?crag? which formed when calcium carbonate was deposited around individual pebbles and cobbles in a gravel bed.
The thickness of the drift in Van Buren County ranges from about 140 to 532 feet. The drift is thickest in two roughly parallel bands extending northeast to southwest, one through the Bangor area and the other through the Lawton area.
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Bedrock Geology in Southwest Michigan
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Southwest Michigan is located on the southwestern flank of the Michigan Basin. A bedrock feature centered on Gratiot County, this structural depression resembles a gigantic set of nested bowls. Everywhere in southwest Michigan bedrock units slope gently to the center of the Basin.
The oldest bedrock units underlie the glacial deposits in Berrien and Cass Counties, and the rocks immediately underlying the glacial sediments are progressively younger towards the center of the basin. Berrien, Cass, St. Joseph, Branch and most of Van Buren, Ottawa, Muskegon, Kalamazoo and Calhoun Counties are underlain by shale. Eaton. Ionia, most of Kent and portions of Kalamazoo, Calhoun, Barry, Muskegon and Ottawa counties are underlain by sandstone or sandstone and shale.
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Page Last Updated: 7/15/2003
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