| Title | Onshore-offshore correlation of central Lake Erie glacial deposits |
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| Author | Lewis, C F M ;
Barnett, P J; Cameron, G D M; Todd, B J |
| Source | Canadian Journal of Earth Sciences 2023 p. 1-24, https://doi.org/10.1139/cjes-2023-0017  Open Access |
| Image |  |
| Year | 2023 |
| Alt Series | Natural Resources Canada, Contribution Series 20210264 |
| Publisher | Canadian Science Publishing |
| Document | serial |
| Lang. | English |
| Media | paper; digital; on-line |
| File format | pdf; html |
| Province | Ontario |
| Area | Lake Erie; Canada; United States of America |
| Lat/Long WENS | -84.0000 -78.0000 43.0000 41.0000 |
| Subjects | Science and Technology; seismology; glacial deposits; seismic profiles |
| Illustrations | location maps; diagrams; seismic reflection profiles; tables |
| Program | Climate Change Geoscience |
| Released | 2023 05 11 |
| Abstract | Dive observations, echogram transects, core sampling, and a seismic profile revealed that the lake bed of north-central Lake Erie is an extensive terrace cut by storm waves and currents. The terrace is
an erosional unconformity on which Late Wisconsinan (Port Bruce and Mackinaw) glacial units crop out. Beds of massive diamictons, and glaciolacustrine sediments containing parallel reflections, crop out alternately from west to east, resulting from
an oscillatory ice retreat. These beds correlate with the Port Stanley Drift (Port Bruce phase) and Wentworth Drift (Mackinaw phase) exposed in nearby shore bluffs and onshore moraines. The Port Bruce glacier and earlier readvances formed ice tongues
and ice shelves in the central basin. Diamicton layers, some with debris flows, constitute the Port Stanley Till (offshore units M and O). A glaciolacustrine unit N was deposited during Port Bruce glacier recessions. Glaciolacustrine unit P lies
between Port Bruce unit O and the Mackinaw Wentworth Till, unit Q. A subsequent glaciolacustrine unit R overlaps unit Q. The onshore Galt and Moffat moraines, composed of Wentworth Till, correlate with ridges of the Norfolk moraine unit Q which
extend across Lake Erie between the base of Long Point, Ontario, and Erie, Pennsylvania. The onshore Paris moraine appears to have been eroded on the wave-cut terrace and is evident offshore only near the south shore of Lake Erie. Laminated unit S,
younger than unit R, occurs in the western part of central Erie basin, and correlates with overflow of Lake Algonquin from the Huron basin. |
| Summary | (Plain Language Summary, not published)
The lake bed of Lake Erie up to 30 to 40 km off the northern shore of the central Erie basin is a terrace cut by storm wave and current action. It is an
eroded surface on which alternating glacial sediment units of ice-deposited till and water-deposited sediment crop out. These units were investigated with dive observations, corers, boreholes, and by echo sounding traverses. Sediment ridges marking
the glacier's former positions were found in the Erieau-Cleveland Moraine and Norfolk Moraine on the western and eastern sides of the Lake Erie central basin. These ice-deposited sediments alternated with glacial lake-deposited laminated sediments.
By tracking their offshore boundaries towards shore, the sedimentary glacial units were identified and dated by their correlation to boundaries of better-known sediment units exposed in the shore bluffs of northern Lake Erie. The surveyed glacial
laminated sediments were found to be deposits of glacial lakes Maumee and Arkona, approximately 17,500 to 16,000 years old. |
| GEOSCAN ID | 328913 |
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