A meteor or comet impact near Quebec heaved a rain of hot melted rock along North America’s Atlantic Coast about 12,900 years ago, a new study claims.
Scientists have traced the geochemical signature of the BB-sized spherules that rained down back to their source, the 1.5-billion-year-old Quebecia terrane in northeastern Canada near the Gulf of Saint Lawrence. At the time of the impact, the region was covered by a continental ice sheet, like Antarctica and Greenland are today.
“We have provided evidence for an impact on top of the ice sheet,” said study co-author Mukul Sharma, a geochemist at Dartmouth College in Hanover, N.H. The results were published today (Sept. 2) in the journal Proceedings of the National Academy of Sciences…..
…..Scientists on the other side of the impact theory debate are not so sure.
“At this point, the pro-impact literature is fringe sciencebeing promoted by a single journal,” said Nicholas Pinter, a geologist at Southern Illinois University in Carbondale, who was not involved in the PNAS research.