What Made This Huge Hole Under Greenland?

In the mid-2010s, researchers discovered something odd underneath Greenland - there was a giant hole under a glacier, and they had no idea what had caused it. More confusing still, other researchers were searching for the cause of a mini Ice Age that killed off most of the megafauna and wiped out the Clovis people. Could the Greenland hole be the key to this mystery? Scientists turned to a humble little mineral to put all the pieces together: Quartz. Hosted by: Hank Green (he/him)