Electromagnetic geophysical surveys of geo-environmental targets in southern Manitoba

• Main Author: Maris, Virginia
• Language: en_US
• Published: 2007
• Online Access: http://hdl.handle.net/1993/1923

Electromagnetic (EM) geophysical methods including low induction number frequency-domain EM (EM31), time-domain EM (TEM), DC-resistivity and ground penetrating radar (GPR) methods were used to investigate four different geo-environmental targets in southern Manitoba. Geophysical surveys were done in the Interlake Plain, Red River Plain and Precambrian Shield, in a range of environments representative of southern Manitoba. Geophysical surveys were done at two sites near deposits of gypsum rosettes in Winnipeg and Letellier and at two sites of paleo-iceberg scours near Lorette. The scours were incised into glaciolacustrine clays deposited in glacial Lake Agassiz and infilled with sediments of the overlying Complex Zone. Geophysical surveys were done at Sylvan to investigate kaolin deposits and the paleokarst surface that hosts them. Collapsed sinkholes near Narcisse provide pathways for red-sided garter snakes to migrate into communal underground winter hibernaculums and survive the winter. A known cavity extending from a den was imaged using GPR. TEM surveys using a PROTEM47 with a 100 x 100 m transmitter loop were done at four sites in the Lac du Bonnet Batholith of the Precambrian Shield. (Abstract shortened by UMI.)