Wisconsin Stratigraphy at Port Talbot on the North Shore of Lake Erie, Ontario
THE OHIO JOURNAL OF SCIENCE Vol. 58 MARCH, 1958 No. 2 WISCONSIN STRATIGRAPHY AT PORT TALBOT ON THE NORTH SHORE OF LAKE ERIE, ONTARIO A. DREIMANIS Department of Geology, University of Western Ontario, London GENERAL PLEISTOCENE GEOLOGY Most of the area north of Lake Erie is covered by Pleistocene deposits in thickness of 100 to 300 feet, except for both ends of the lake where bedrock is shallower. The surface drift is generally considered to be of Cary and Mankato age (Glacial Map of North America, 1945). In order to obtain a better idea on the Pleistocene stratigraphy of the area north of Lake Erie, the writer has examined hundreds of exposures along the central portion of the lake, between Romney and Port Rowan, Ontario. A brown clayey till, interbedded and covered by lacustrine deposits, was found to be the principal material. This till is in one layer in the eastern half of the area studied, but it consists of two or three towards the west. All three till beds have similar colour, texture and lithologic composition (Dreimanis and Reavely, 1953, p. 238-239). They appear to be deposited by the same ice lobe during the oscillatory retreat. A common name, the "upper till," have been applied to these till beds because each of them is exposed on the surface farther north of Lake Erie. A similar clayey till extends also south of the lake (White, 1951, p. 971). A deeper sandy till has been found either in exposures (Dreimanis and Reavely, 1953, p. 239) or reported by well logs through the entire area studied, and it has been called the "lower till." Similar sandy tills underlie the surface drift in northern Ohio (Shepps, 1953, p.
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