Hiawatha impact structure

The Hiawatha impact structure is a probable impact structure discovered beneath the Hiawatha Glacier in northwest Greenland, from which it gets its name. It was identified using airborne radar surveys that showed the presence of a crater-like depression in the bedrock beneath the ice. Shocked quartz grains and melt rock clasts have been found in fluvio-glacial sediments deposited by a river that drains the area of the structure. The timing of the impact has been dated using argon-argon dating and uranium-lead dating of zircon crystals within the melt rock to 57.99 ± 0.54 million years ago, during the late Paleocene.

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