Pre-Mississippian tectonic affinity across the Canada Basin-Arctic margins of Alaska and Canada

摘要

New and reprocessed seismic reflection data on the Alaskan and Canadian Arctic margins of the Canada Basin, together with geologic constraints from exploration wells and outcrops, reveal structural and stratigraphic relationships in pre-Mississippian rocks that constrain models of Canada Basin opening. Lithostratigraphic age and acoustic character indicate that the Devonian and older passive-margin to foreland-basin succession in the Canadian M'Clure Strait is also found on the central Alaska margin. This succession also displays similar structural geometry and relief as well as deformational age on both margins. Moreover, Middle Devonian to Early Mississippian tectonic vergence-north directed on the central Alaska margin and east directed in the Canadian M'Clure Strait-indicates a common direction of tectonic transport if the two margins were conjugate. All of these observations demonstrate that pre-Mississippian rocks of the Alaskan and Canadian Arctic margins share a common tectonic history of uplift and exhumation and that the two margins were conjugates prior to opening of the Canada Basin.