The meltwater draining from under it carries sediments with shocked quartz. The radar shows a crater-like depression, with a rim about 300 meters high! (They predict 800m when freshly made.) Figure E is pretty evocative of what happens when a glacier erodes things.
The crater looks pretty recent. It can't be younger than about 12K years, or much older than a million or so. They guess the meteorite was about 1.5km diameter iron--or more if it had to pound through an ice sheet.
A core sample or 5 would be nice to have. And maybe a gravity scan.
Without a clear date it's hard to connect it with anything else. Nobody found any obvious ejecta from the crater in the ice, but with ice sheets advancing and retreating there might not be much left to find--especially if this was a grazing impact.
It's pretty dramatic:
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