| Paper No. 19-9 | ||
| Presentation Time: 8:00 AM-12:00 PM | ||
| “TWO-STORIED SOILS” AND THEIR RELEVANCE TO HOLOCENE LANDSCAPE HISTORY IN EASTERN UPPER MICHIGAN | ||
|
LOOPE, Walter L., U.S. Geol Survey, N8391 Sand Point Road, P.O. Box 40, Munising, MI 49862, walter_loope@usgs.gov, FISHER, Timothy G., Department of Geosciences, Indiana Univ NW, 3400 Broadway, Gary, IN 46408, and WHITNEY, Gregory D., USDA-Nat Recources Conservation Service, Schoolcraft Co. Soil Suvey, County Airport Building, Manistique, MI 49854 The availability of detailed Holocene hydrographs of the upper Great Lakes has stimulated research of coastal landforms as well as questions of how lake-level change on the Great Lakes might have influenced inland and upland sites. “Two-storied soils”, soils whose profiles clearly suggest drastic changes in their genetic history, are common within the Tahquamenon River watershed that drains to Lake Superior in eastern Upper Michigan. Well-developed spodic horizons overlain by a varying thickness of peat or muck characterize about 20% of the basin. These soils apparently reflect several thousand years of development under pineland vegetation followed by landscape drowning by a rising water table. It has been suggested that just such a widespread rise in the upland water table would have accompanied a rising regional base level during the Nipissing transgression of the upper Great Lakes. Another possibility is that coastal dune building stemming from lake high stands led to channel aggradation which diminished upstream gradients, impounded shallow reservoirs and initiated wetland growth. To gain insight as to whether either of these scenarios is likely, we examined modern soils data for Luce and Chippewa County, MI, noting the relative watershed position of soil series with “two-storied” profiles. In addition, we vibracored wetlands within the Tahquamenon River watershed where “two storied” soils are mapped. We split and described the cores using standard soil stratigraphic methods and submitted organic material from key horizons for 14C dating. Our results should shed light on the history of wetland initiation and growth relative to Great Lakes hydrographs. | ||
|
North-Central Section - 37th Annual Meeting (March 24–25, 2003)
General Information for this Meeting | ||
| Session No. 19--Booth# 9 Quaternary Geology of the U.S. Midwest (Posters) Kansas City Airport Hilton: Shawnee A 8:00 AM-12:00 PM, Tuesday, March 25, 2003 | ||
© Copyright 2003 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions. | ||