by: Charles O’Dale
- CONFIRMED: an impact site with documented shock features and/or meteoritic material and/or observed fall.
Name | Diameter (km) | Age (megayears) | Dating method | Morphological type | Notes |
---|---|---|---|---|---|
Barringer, Arizona | 1.19 | 0.049 ±0.003 | Radioactive decay | Simple1 | Jointed |
Beaverhead, Montana/Idaho | ~100 | ~600 | K-Ar, 40Ar/39Ar and Rb-Sr | Peak ring1 | Allochthonous |
Brent, Ontario | 3.8 | 396 ± 20 | K-Ar studies on the coarsely crystalline melt rocks | Simple1 | Overflight of Brent Crater |
Calvin, Michigan | 7.24 | 450 ± 10 | Geological dating | Complex1 | |
Carswell, Saskatchewan | 39 | 115 ± 10 | 40Ar/39Ar | Peak ring1 | Multi-ring impact? |
Charlevoix, Quebec | 54 | 342 ± 15 | K-Ar | Peak ring1 | Elevated Earthquake Zone |
Chesapeake, Virginia | 85 | 33.99 ± 0.71 | Geological dating | Complex1 | Coesite in suevites |
Chicxulub, Yucatan, Mexico | 150 | 66.043 ±0.011 | 40Ar/39Ar | Peak ring basin5 | Cretaceous-Paleogene |
Clearwater East, Quebec | 26 | ~460–470 | Rb-Sr melt rocks | Complex1 | Chondrite-type |
Clearwater West, Quebec | 32 | 290 ± 20 | K-Ar melt rocks | Peak ring1 | Maskelynite |
Cloud Creek, Wyoming | 7 | ~190 ± 30 | Geological dating | Complex2 | Chronostratigraphic |
Crooked Creek, Missouri | ~7 | ~348 – 323 | Geological dating | Complex2 | Serial impact event? |
Decaturville Structure, Missouri | 5.5 | 260-323 | Geological dating | CONFIRMED Complex2 | |
Deep Bay, Saskatchewan | 9.5 | 99 ± 4 | Geological dating | Simple Flat-floored1 | Cretaceous sediments |
Des Plaines, Illinois | 8 | <280 | Geological dating | Complex2 | |
Douglas Wyoming | ~0.08 | ~280 | Sedimentological boundary | Simple | Multiple Strewn Field |
Eagle Butte, Alberta | 10 | <65 | Geological dating | Complex2 | Shatter-coned Cretaceous rocks |
Elbow, Saskatchewan | 8 | 395 ± 25 | Geological dating | Complex2 | Brecciated Devonian strata |
Flynn Creek, Tennessee | ~3.8 | 382.03 ± 21 | Geological dating | Complex2 | Shattercones |
Glasford, Illinois | ~4 | 455 ± 2 | Geological dating | Complex2 | Shattercones, shock metamorphism |
Glover Bluff, Wisconsin | 8 | <500 | Geological dating | Complex2 | |
Gow, Saskatchewan | 5 | <250 | Radioactive decay | CONFIRMED Transitional | A transitional form between a simple bowl-shaped crater and a complex crater with a central uplift. |
Haviland, Kansas | 0.01 | 0.02 ±0.002 | Geological dating | Simple1 | Brenham meteorite |
Hiawatha, Greenland | 31 | 2.5 – 0.0117 | Geological dating | Complex3 | Younger Drias Extinction |
Holleford, Ontario | 2.35 | 550 ±100 | Geological dating | Simple1 | Overflight of Holleford Crater |
Ile Rouleau, Quebec | 4 | <300 | Geological dating | Complex3 | Age based on stratigraphy |
Kentland, Indiana | ~13 | >97 | Geological dating | Complex1 | Quarry |
Lac Couture, Quebec | 8 | 425 ± 25 | Ar40-Ar39 melt rock | Complex1 | Submerged central peak |
Lac La Moinerie, Quebec | 8 | 400 ± 50 | Ar40-Ar39 melt rock | Complex1 | |
Manicouagan, Quebec | 100 | 214 ± 1 | Zircon/melt rock dating | Peak ring basin5 | Maskelynite |
Manson, Iowa | ~35 | 73.8 | Ar40-Ar39 melt rock | Central peak1 | No surface evidence |
Maple Creek, Saskatchewan | 6 | <75 | Geological & radioactive decay dating | Complex5 | Disrupts Late Cretaceous rocks |
Middlesboro, Kentucky | 6 | <300 | Geological dating | Complex5 | Dates to the formation of the supercontinent Pangaea 300 million years ago |
Mistastin, Labrador | 28 | 36.6 ± 2 | Ar40-Ar39 melt rock | Central peak basin6 | Maskelynite |
Montagnais, off Nova Scotia | 45 | 50.5 ± 0.76 | K-Ar, 40Ar/39Ar and Rb-Sr | Complex1 | Submerged south of Nova Scotia, Canada |
Newporte, North Dakota | 3.2 | <500 | Geological biostratigraphic dating | Simple2 | No surface evidence |
Nicholson Lake, North West Territories | 12.5 | 389 ± 6.7 | Pb/U | Complex1 | The large island within the lake is the eroded central peak |
Pilot Lake, North West Territories | 6 | 445 ± 2 | K-Ar, 40Ar/39Ar and Rb-Sr | Complex2 | Dating based on one sample |
Pingualuit, Quebec | 3.44 | 1.4 ± 0.1 | Ar40-Ar39 melt rock | Simple1 | Overflight of Pingualuit Crater |
Presqu’ile, Quebec | 24 | <500 | Geological dating | Complex1 | High level erosion |
Red Wing, North Dakota | 9.1 | 200 ± 25 | Geological dating | Probable Complex8 | Stratigraphy |
Rock Elm, Wisconsin | 6 | 420–440 | Geological dating | Complex7 | Youngest exposed rocks |
Slate Islands, Lake Superior | 32 | 436 Ma ± 3 | Ar40-Ar39 melt rock | Complex1 | Pseudotachylite dating |
Steen River Albera | 25 | 91 ± 7 | K-Ar pyroclastic vesicular rock | Complex1 | Magnesioferrite MgFe2O4 |
St. Martin, Manitoba | ~40 | 227.8 ±0.9 | Ar40-Ar39 melt rock | Complex1 | Maskelynite – Dauphin River diversion? |
Sudbury, Ontario | 250 | 1852 +4/-3 | U-Pb zircon | Multi ring?1 | Sudbury Distal Ejecta |
Viewfield, Saskatchewan | 2.5 | 190 ± 20 | Geological dating | Simple2 | Jurassic-Triasic post-impact deposit |
Wanapitei, Ontario | 3 to 7.5 | 37.2 ± 1.2 | K/Ar, Ar40-Ar39 melt rock | Simple – Possible flat-floored?1 | Maskelynite – L or LL chondrite projectile |
Wells Creek, Tennessee, USA | ~12 | 200 ± 100 | Geological dating | CONFIRMED Complex | Shattercones |
West Hawk, Manitoba | 2.44 | 100 | Geological dating | Simple1 | No reliable age |
Whitecourt, Alberta | 0.036 | 0.00113 | 14C dating of charcoal | Simple1 | Medium octahedrite (Om) IIIAB |
1 Dence, Michael R. Structural evidence from shock metamorphism in simple and complex impact craters: Linking observations to theory. Meteoritics & Planetary Science 39. Nr 2, 267-286 (2004).
2 Grieve R.A.F., Impact structures in Canada, Geological Association of Canada, 2006.
3 Spray J.G. et al. A marine magnetic study of the Ile Rouleau impact structure, Lake Mistassini, Quebec Canada. Meteoritics, 70th Annual Meeting (2007).
4 Eugene M. Shoemaker, Bryan J. Kriens, Ken E. Herkenhop, GEOLOGY OF THE UPHEAVAL DOME IMPACT STRUCTURE, SOUTHEAST UTAH. Journal of Geophysical Research–Planets, April 16, 1998.
5 Grieve R.A.F. and Head J.W. The Manicouagan impact structure: An analysis of its original dimensions and form. Journal of Geophysical Research 88:A807-A818 (1983).
6 French, B.M. Traces of Catastrophe, Lunar and Planetary Institute, 1998
7 Cordua, W. S., “The Rock Elm Structure, Pierce County, Wisconsin, a possible cryptoexplosion structure”, Geology, vol. 13, p. 372-374. 1985.
8Donofrio, Richard R., IMPACT CRATERS: IMPLICATIONS FOR BASEMENT HYDROCARBON PRODUCTION. Journal of Petroleum Geology, 3, 3, pp. 279-302, 1981.