The Bow City Impact Crater is a probable meteorite impact crater located in southern Alberta, Canada. The 8-kilometre-wide (5.0 mi) crater was discovered in 2012 by Wei Xie of the University of Alberta. The crater is estimated to have formed approximately 70 million years ago. The crater is not directly visible from the surface, as it is buried under approximately a kilometer of overburden. Petrochemical seismic studies provided the first clues to the existence of the crater.
^Nadia Drake (2012-12-04). "New Buried Aasteroid Impact Crater Discovered in Canada". Wired magazine. Archived from the original on 2013-02-19. “I was really surprised,” said Wei Xie, a graduate student in geophysics at the University of Alberta, who presented the find on Dec. 3 at the American Geophysical Union conference. So far, Xie says, only a handful of these buried craters are known. That’s likely to change. “Our technology is really improving,” she said.
^Scott Sutherland (2012-12-04). "Ancient asteroid impact crater discovered near Alberta ghost town". Geekquinox. Archived from the original on 2013-02-19. The seismic map of the crater shows the structure of it quite well, with its low-lying interior and characteristic central peak. The team also noted some potentially unique features of the crater, which indicate that some of the sediments were pushed directly outward from the impact, rather than being blown upwards (as would be expected).
^Rosemary Westwood (2012-12-06). "Grad student finds new asteroid crater in southern Alberta". Macleans magazine. Archived from the original on 2013-02-19. The crater has long been covered over and is estimated to be about 70 million years old. It took an analysis of data from boreholes drilled in the area and seismic wave surveys to show the giant crater below the surface. Xie and her colleagues will continue to search for definite proof, and they are looking for evidence of impact known as “shocked minerals.”