Abstract

The large amount of new data obtained through the recently completed geological investigation in eastern North Greenland calls for substantial re-appraisal of its geologic history. In our opinion, the bulk of the data favours a highly mobilistic model for the geologic development of North Greenland — for the Devonian-Tertiary interval — and this paper attempts a broad synthesis within this frame.

Late Caledonian events in North Greenland include foreland folding and thrusting in the East Greenland Fold Belt as well as gravitational sliding and intrusion in the North Greenland Fold Belt. In the Early Carboniferous, the North Greenland Fold Belt was affected by folding of the Ellesmerian Orogeny, i.e. the main Paleozoic deformation in the Innuitian Mobile Belt. Throughout most of the Phanerozoic, the major E - W-trending Harder Fjord Fault Zone (HFFZ) occupies a central position, with several periods of large-scale strike-slip movements in the Paleozoic and the Mesozoic. It is suggested that this fault zone originated as part of a fundamental fault system crossing the northernmost part of the Canadian Arctic Archipelago to join the Kaltag Fault in Alaska. Towards the east, later developments in the HFFZ include also NW - SE-trending forces which, in the Late Cretaceous, developed into a strike-slip mobile belt paralleling the fracture zones separating Greenland and Svalbard.

The onshore part of the Wandel Hav Strike-Slip Mobile Belt comprises several pull-apart basins which were initiated, accumulated thick piles of marine, continental or volcanic strata, and finally went through substantial compression, all within the Late Cretaceous and early Paleocene.

Post-Paleocene doming with associated strong heat-flow increase, perhaps as the southernmost extension of the Nansen Ridge, appears to be the last major event recorded in North Greenland.