The Quaternary of Wisconsin: A review of stratigraphy and glaciation history

• Published in: Developments in Quaternary Science Vol. 2; pp. 295 - 311
• Main Authors: Syverson, Kent M., Colgan, Patrick M.
• Format: Book Chapter
• Language: English
• Published: The Netherlands Elsevier Science & Technology 2004
• Subjects: Geology & the lithosphere
• ISBN: 9780444515926; 0444515925
• ISSN: 1571-0866
• DOI: 10.1016/S1571-0866(04)80205-7

Wisconsin was glaciated several times during the Quaternary and lies well north of the maximum extent of Quaternary glaciations. However, the Driftless Area of south-western Wisconsin remained unglaciated even though areas to the south were glaciated several times. Glacial, periglacial, alluvial, and aeolian sediments from pre-Illinoian, Illinoian, and Wisconsinan Glaciations are present, but age control for all except Late Wisconsinan events is limited to palaeosols and palaeomagnetic data. The chapter reviews that glacial sediment covers approximately three fourths of the 145,000-km2 land surface in Wisconsin. Ice flowing from three major source regions deposited sediment. Ice from the Labradoran ice dome to the north-east flowed out of the Superior lowland and deposited red tills with Precambrian basalt, banded iron formation and red sandstone erratics. Labradoran ice flowing out of the Green Bay and Lake Michigan lowlands deposited calcareous tills whose grain size was strongly influenced by proglacial lakes within those lowlands. Wisconsin provides an ideal laboratory for evaluating how the complex sedimentology, stratigraphy, and landform distribution reflect past ice dynamics. The chapter summarizes the glacial history of Wisconsin and suggest areas of future research that would aid reconstruction of the region's glacial history.