| Autor: |
Szabo, John P., Bradley, Kristine, Tevesz, Michael J. S., Richards, R. Peter |
| Zdroj: |
Journal of Great Lakes Research; 2003, Vol. 29 Issue 4, p566-580, 13p, 4 Diagrams, 5 Charts, 1 Graph, 2 Maps |
| Abstrakt: |
Laboratory data from a rare set of samples collected during the 1920s from foundation borings for the Cleveland Union Terminal and Eagle Avenue Bridge provide new information about Late Quaternary stratigraphy beneath Cleveland, Ohio, on the south shore of Lake Erie. Samples represent ten unconsolidated units ranging in age from the Illinoian glaciation through modern anthropogenic fill. The oldest deposits may include the Illinoian Keefus, Mogadore, and Northampton tills and their associated lacustrine and outwash deposits. There is no evidence of Sangamonian deposits or the Late Wisconsinan Kent advance. Hiram Till deposited in close association with proglacial lakes is the only Late Wisconsinan diamict found in the area. Radiocarbon dates on twigs in lacustrine deposits suggest the landscape was deglaciated and vegetated by 14,500 yr BP. Lakes Maumee, Arkona, and Whittlesey immersed the area, and as the water level dropped to the Warren levels, deltaic deposits may have been reworked into beach ridges. The post-glacial Cuyahoga River downcut possibly 40 m into Illinoian deposits in response to the drop in water level to that of Early Lake Erie. Subsequently, this post-glacial valley filled with Holocene alluvium as Lake Erie rose to modern levels. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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