Cenozoic structural evolution on northern Banks Island, N.W.T. Canada

Abstract

The onshore structural architecture and evolution of large segments of the Arctic continental margin are poorly known because of the generally poor outcrop of pre-Neogene rocks, the remoteness of the area and extent of Neogene cover. Fieldwork on Banks Island during the summer of 2016 has shown that the Devonian, Cretaceous and Paleogene deposits on northern Banks Island are characterized by a number of local, restricted deformation zones, which we interpret to indicate both dextral and subordinate sinistral strike-slip deformation along NNE–SSW striking structures parallel to the continental margin of Banks Island. The presence of Cenozoic strike-slip deformation on Banks Island extends the area of known Cenozoic strike-slip along the continental margin southwestward from where it has been previously documented on northern Ellesmere Island. In addition, field and seismic data indicate that the sedimentary rocks on Banks Island have been affected by extensional movements before and after the strike-slip deformation. The observation of strike-slip motion on Banks Island may imply a component of strike slip over the whole Paleogene North American margin.