Abstract

Pre-drift reconstruction of continental plates around the North Atlantic, based on the geology of adjacent margins, indicates that: the Essaouira Basin was opposite the Scotian Basin; the Rif area of Morocco was southwest of the Newfoundland Ridge; and Iberia lay south of the Flemish Cap east of the Grand Banks. During early Mesozoic time, tensional stresses preceding continental breakup resulted in the development of northeast-southwest trending taphrogenic basins along the southern flank of the Appalachian Orogen. Initial sedimentation consisted of continental clastics followed by salt which was deposited from carbonate and sulphate depleted brines from the Tethys.

Following the initiation of sea-floor spreading between the North American and African plates, at about 170 m.y., a normal marine regime was established and along the Canadian margin a thick shelf edge carbonate bank developed simultaneously with back bank elastics and deeper water shales. A tectonic pulse, associated with the separation of the European and North American plates in Late Jurassic to Early Cretaceous time resulted in uplift of a large salient southeast of Newfoundland. During the same time a regional regression resulted in the development of a series of delta systems along the northeast margin of North America. The Late Cretaceous eustatic rise of sea level resulted in the deposition of a thick transgressive clastic wedge. The transgression culminated in the early Tertiary. A subsequent predominantly regressive cycle deposited an upward coarsening, prograding clastic sequence which constructed the present day continental shelves of Atlantic Canada.