#440: Movie clip played on default viewer

Movie initial view is to the south-southwest, looking at ice-contact and stagnant ice features on the St. Croix moraine (Superior Lobe). Stagnation zones are characterized by a hummocky land surface comprised of hills (kames, crevasse ridges, and ice-walled lake plains) and depressions (kettles). These form when the ice front retreats and large fractures develop that accumulate sediments. During this retreat, blocks of ice are sometimes abandoned or buried. When the ice melts from around or under accumulated sediments, hills and depressions form as the sediment erodes, settles, and collapses.

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