Week 2014.21 (May 25-31) ~ A lasting impact

Once upon a time, on a day perhaps very much like today, long before mammals appeared on Earth, when the landscape teemed with primitive insects and amphibians crawled through the ferns, a two-kilometer wide extraterrestrial object appeared over the skies of what is now eastern Canada and slammed into the Earth. The energy released from that asteroid collision was great enough to fracture the Earth’s crust and reactivate several of the area’s ancient earthquake faults. Now, some 350 million years later, the only visible artifact of that tumultuous event is a heavily eroded crater near Charlevoix, Quebec, on the north shore of the St Lawrence River. But if you listen closely to the Earth today, you can still hear the distant echoes of that impact, in the form of frequent small earthquakes along this stretch of the St Lawrence River, eastern Canada’s most seismically active region.
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