Basement extension on the Newfoundland continental margin (Canadian east coast)

Abstract

The margin consists of a series of intracratonic basins and ridges and a complex continent-ocean transition zone formed during several Mesozoic rifting periods. Recent industry seismic lines and several deep seismic reflection profiles (Lithoprobe East) allow for the recognition of coherent reflections of intra-basement provenance. The widespread reactivation of pre-existing Precambrian and Paleozoic zones of weakness as rift-bounding faults is questioned, and examples of deviations from the previous geological grain are offered. A simple-shear geodynamic model of continental extension evolving into a double rift system that includes transition zones beneath the abandoned rifts and at the continent-ocean boundary is suggested. -from Author