STATUS OF THE LAKE WINNIPEG PROJECT (NTS 62I, 62P, 63A, 63B, 63G AND 63H)

• Main Authors: Thorleifson, H., Anderson, T., Betcher, R., Bezys, R., Buhay, W., Burbidge, S., Cobb, D., Courtier, N., Doering, J., Fisher-Smith, G., Forbes, D., Franzin, W., Frobel, D., Fuchs, D., Gibson, C., Henderson, P., Jarrett, K., James, T., King, J., Kling, H., Lambert, A., Last, W., Lewis, M., Lockhart, L., Matile, G., McKinnon, T., Moran, K., Nielsen, E., Pullan, S., Rack, F., Risberg, J., Rodrigues, C., Salki, A., Schroder-Adams, C., Stainton, M., Telka, A., Todd, B., Vance, R., Weber, W.
• Format: Book Part
• Language: English
• Published: Government of Manitoba 1998
• Subjects: Lake Winnipeg; Geological Survey; Lake Winnipeg Basin; Canada; Long Point; Churchill
• Online Access: http://hdl.handle.net/1993/30867

The Lake Winnipeg Project was launched by the Geological Survey of Canada (GSC) and Manitoba Geological Services Branch (MGSB) in 1994, with the support of Manitoba Hydro and the Manitoba Sustainable Development Innovations Fund, in order to support management of issues such as shoreline erosion and water quality. A four-week cruise of the Canadian Coast Guard Ship (CCGS) Namao in 1994 was followed by a similar effort in 1996. Low frequency air gun seismic, high frequency seismic, side-scan sonar, and coring operations, guided by real-time differential global positioning system (GPS) navigation, were supplemented by limnological and biological sampling carried out in cooperation with the Freshwater Institute. A five-year program of absolute gravity measurements and GPS data collection is monitoring uplift, a key factor in shoreline erosion, along a transect from Iowa to Churchill. Accompanying research on shoreline processes has included reconnaissance surveys in 1994, targeted investigations in 1996, and a month-long intensive effort in September 1997. Previously acquired wave data have been supplemented by data from three waverider buoys deployed in 1996. Although targeted follow-up research is anticipated, final outputs from the Lake Winnipeg Project are in preparation for release in 1999. Two major questions have been addressed by this work: What is the structure of the Lake Winnipeg basin? Results have demonstrated that the structure of sediment and rock below Lake Winnipeg dramatically differs from expectations. Prior to the 1994 cruise, it was thought that sedimentary rocks extended close to the eastern shore, and that these rocks were buried by at most 15 m of sediment. In fact, sedimentary rocks only extend 10 km east from the end of Long Point, and terminate at a buried escarpment south of Hecla Island. Beyond these Paleozoic rocks, sediments consisting almost entirely of Lake Agassiz clay reach unanticipated thicknesses of over 50 m in the South Basin and over 100 m in the North Basin. Till and other ...