Cretaceous tectonism and volcanism in the eastern Scotian Basin, offshore Nova Scotia

Abstract

Early Cretaceous tectonism and volcanism is widespread in the eastern Mesozoic-Cenozoic Scotian Basin. The precise stratigraphic position of volcanic rocks within wells has been re-evaluated and the volcanological character of the rocks refined by study of cuttings and well logs. Hauterivian-Barremian volcanic rocks on the SW Grand Banks and Aptian-Albian volcanic rocks in the Orpheus Graben and SE Scotian Shelf are likely the result of Strombolian type eruptions. The timing of regional unconformities appears to mark the onset of different components of the volcanic system. The distribution of volcanism is related to the complex opening history of Europe from North America. Widespread volcanic activity indicates a regional and long-lived magma source, which resulted in elevated regional heat flow. Effects of this heat flow are seen in sediments within the Sable sub-basin, but was insufficient to significantly influence the petroleum system.