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Ice-Rich Niche Block Collapse
This is part of the coastline of the Beaufort Sea in the Teshekpuk Lake Special Area in Arctic Alaska. Permafrost here is very ice-rich near the surface and coastline erosion occurs by thermo-mechanical erosion where once the sea is ice free the ocean contacts the bluff toe, cutting a niche that eventually collapses as a huge block of tundra mostly ice. This photo was taken between Lonely and Point Drew in late August 2008.