Permian tectonism in the Sverdrup Basin, Axel Heiberg Island, Arctic Canada

Abstract

The Mississippian to Eocene Sverdrup Basin in the Canadian Arctic has long been considered to have originated as a rift following the collapse of the Devonian to Mississippian Ellesmerian Orogen. From latest Pennsylvanian to Middle Permian time, several tectonic events were accompanied by outpouring of volcanic material and the addition of a northern sediment source, presently lying beneath the Arctic Ocean. This thesis encompasses geochronological, stratigraphic and structural analyses with a focus on Pennsylvanian to Lower Triassic strata and deformational events on the northern portion of the Sverdrup Basin. Northerly-sourced sediments contain a syndepositional zircon sub-population, deposited in an area that experienced multiple Pennsylvanian to Triassic uplift and deformation pulses, providing evidence for the existence of a magmatically and tectonically active margin to the north. In contrast to the passive margin setting traditionally assumed for northern Laurentia, these results require a reevaluation of the Sverdrup Basin as a backarc to retroarc basin.