Here is an earlier article about the impact event mentioned in this article. Did it exterminate the Clovis folks? Don't know yet...interesting ideas though.
Ice Age Ends Smashingly: Did A Comet Blow Up Over Eastern Canada? (More) (Carolina Bays)
I've often wondered if the Barringer Impact 50,000 years ago wiped out these even earlier folks mentioned in the link below.
JMO, but Barringer Crater seems a little smallish to have created much havoc. Locally, it would have been quite a show though.
I STILL believe paleo types' best bet for finding artifacts or other evidence of really old "new" world civilizations will be on the continental shelves. Or even around the edges of dried up lakes, like Bonneville, or even near ancient river and creek beds. Like Topper for example.
Holy Cow! That thing almost hit the highway!
It really needn't have exterminated the people - if the comet event destroyed their food source it would have had a catastrophic impact on their culture, allowing rivals to challenge them.