Ancient Crater Hints at Massive and Cataclysmic Meteorite Impact

Scientists have discovered an ancient, ring-like structure in southern Alberta that hints at a cataclysmic event. The geological findings suggest that the area was struck by a meteorite large enough to leave an eight-kilometer-wide crater and powerful enough to produce an explosion strong enough to destroy present-day Calgary.

The structure itself has been eroded over time by glaciers, so it's difficult to say with full certainty that it was caused by a meteorite impact. Yet it's very likely that this was the case; at least, that's what the evidence points toward.

"We know that the impact occurred within the last 70 million years, and in that time about 1.5 km of sediment has been eroded," said Doug Schmitt, one of the researchers, in a news release. "That makes it really hard to pin down and exactly date the impact."

Only the "roots" remain of the crater, which has created a semicircular depression eight kilometers across with a central peak. When it first formed, the crater likely reached a depth of 1.6 to 2.4 kilometers. That type of impact would have had catastrophic results for the surrounding area.

"An impact of this magnitude would kill everything for quite a distance," said Wei Xie, one of the researchers, in a news release. "If it happened today, Calgary (200 km to the northwest) would be completely fried and in Edmonton (500 km northwest), every window would have been blown out. Something of that size, throwing that much debris in the air, potentially would have global consequences; there could have been ramifications for decades."

Currently, the researchers are trying to learn a bit more about this ancient impact. They're using seismic data in order to get a closer look at this crater in order to tell what might have happened in the past.

The findings are published in the journal Meteorites & Planetary Science.