by: Charles O’Dale
| Morphology | Name | Diameter | Notes |
|---|---|---|---|
| Circular Formation | Alsever Lake, Ontario | ~4 Kilometres | Brent analog |
| Circular Formation | Brackett Lake, NWT | 8.67 Kilometres | |
| Circular Formation | Canoe Lake area, Ontario | 150 Metres | |
| Circular Formation | Colter, Oklahoma, USA | 150 Metres | |
| Circular Formation | La Loche, Saskatchewan | 150 Metres | |
| Circular Formation | North of Lake Superior, Ontario | <50 Metres | |
| Circular Formation | Otter Lake, Quebec | <50 Metres | |
| Circular Formation | Prince Edward Point, Ontario | 400 Metres | |
| Circular Formation | Quorn Lake, Ontario | 1.73 Kilometres | |
| Circular Formation | Riding Mountains, Manitoba | 1.73 Kilometres | |
| Circular Formation | South of Great Bear Lake, NWT | 240 Metres |