Water Expulsion and Pingo Formation in a Region Affected by Subsidence

Abstract

Geophysical evidence indicates that the delta area of the Mackenzie River, Northwest Territories, is affected by tectonic subsidence. Pingos are of sparse occurrence in the Arctic as a whole but they occur in hundreds in the Mackenzie River delta.In a region of subsidence, as recent sediments pass through the base of permafrost, compaction becomes possible. The resulting water expulsion produces an artesian head responsible for building pingos.