Sequence stratigraphy and hydrocarbon potential of regional Upper Cretaceous limestone units, offshore Nova Scotia

摘要

Two regionally widespread limestone units form important seismic markers beneath the Scotian Margin and the Grand Banks: the Upper Turonian-Coniacian Petrel Member of the Dawson Canyon Formation and the Upper Santonian-Maastrichtian Wyandot Formation. They are typically composed of intensely bioturbated, fine-grained, coccolith-dominated limestone (chalk) with minor amounts of other lithologies, and vary in thickness from a few metres to 400 metres.Most information about the Wyandot Formation is from drill cuttings, seismic, and wireline data. Only four wells on the Scotian Shelf have conventional core: Eagle D-21, and Primrose F-41, A-41, and 1A A-41. Based upon the cores, trace fossils are dominated by Zoophycos, Thalassinoides, and Chondrites, and are typical of a deep shelf environment below storm wave base, an interpretation also probably applicable to most of the Petrel Member.