Arctic Piercement Domes
W. W. HEYWOOD
The Isachsen dome on Ellef Ringnes island is a piercement structure made of a central core of Lower Palaeozoic evaporites which intruded nearly horizontal strata of Lower Cretaceous and possibly younger age, and upturned them so that they now crop out as concentric 'rings around the core. The surface evaporites are thought to cap a salt plug. Study of air photographs indicates similar structures at other localities of the Arctic islands.
Air, anhydrite, Basalt, Geological Survey of Canada, gypsum, limestone, Arctic, Basalts, CORE, formation, Gypsum, limestone, Rock, Rocks, Structure