LAC DU BONNET STRUCTURE
- Type: Simple
- Location: N 54° 24′ W 95° 48′
- Diameter: ~3.8 Km;
- Age (ma):~75a
a the age is based on the thin sedimentary cover near the shield boundary.
Poplar Bay, Manitoba. 50°23’N, 95°47’W. This 3 km diameter crater is located in the Interior Platform of the Great Plains. However, it is near the Shield boundary and sedimentary cover is thin. It is aged 75 m.y. The crater has formed a large bay within Lac du Bonnet, somewhat similar to Deep Bay in Reindeer Lake. Aeromagnetic maps have been secured and examined. They indicate signatures favourable to meteoritic impact formation with circular contours, low gradients and a total relief of 100 nT. Map numbers are 4070G and 7124G Pointe du Bois (Clark).
Clark, J .F. MAGNETIC SURVEY DATA AT METEORITIC IMPACT SITES IN NORTH AMERICA Geomagnetic Service of Canada
Brent Dalrymple, Radiometric Dating Does Work! Reports of the National Center for Science Education
Trueman, D. L. ; Evidence in support of a meteorite impact crater at Poplar Bay, Lac du Bonnet, southeastern Manitoba, Canada; Canadian Journal of Earth Sciences, v. 13n. 11, p. 1608-1612; 1976