Genesis of diamicton in the Oak Creek Formation of south‐east Wisconsin, USA

ABSTRACT The clayey diamicton of the Oak Creek Formation was deposited by the Lake Michigan Lobe of the Laurentide Ice Sheet during the late Wisconsin deglaciation. Rapid changes in the position of the ice margin may have been facilitated by a subglacial deforming bed. However, although it is diffic...

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Bibliographic Details
Published in:Sedimentology
Main Author: RONNERT, LARS
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 1992
Subjects:
Online Access:http://dx.doi.org/10.1111/j.1365-3091.1992.tb01033.x
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-3091.1992.tb01033.x
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-3091.1992.tb01033.x
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Summary:ABSTRACT The clayey diamicton of the Oak Creek Formation was deposited by the Lake Michigan Lobe of the Laurentide Ice Sheet during the late Wisconsin deglaciation. Rapid changes in the position of the ice margin may have been facilitated by a subglacial deforming bed. However, although it is difficult to find proof either for or against a subglacial deforming bed, most observations from this investigation are more easily explained by transportation within and deposition from the ice itself. Good exposures of the diamicton units, especially of the lower contacts, along the shore of Lake Michigan, are the basis for the interpretation of basal till genesis. Basal deposition occurred mainly by stagnation and stacking block by block followed by melting out, as opposed to lodgement grain by grain. This interpretation of basal deposition is applicable in other areas and in most topographic environments.