PROPOSED YOUNGER DRYAS GLACIATION OF THE EASTERN SCOTIAN SHELF

A refined synthesis of the stratigraphy of the Scotian Shelf is presented, based on recently published borehole and seismic-reflection data and detailed correlation along high-resolution seismic profiles between the outer banks and the central basins. One of the new stratigraphic units of the outer bank region is of glacigenic origin and represents the last glacial event near the margin of the shelf. These deposits appear to be part of a morainal bank complex formed at a tidewater front. A Younger Dryas age is proposed for the glacial deposits, and the ice may have been widely distributed across the eastern Scotian Shelf. Evidence for the late glaciation is expressed in the central shelf area by an unconformity, which on the bank areas is associated with subglacial meltwater channels. C-14 dates for the basin sediments of this region provide the most reliable chronology for the shelf stratigraphy. The origin of Sable Island is closely related to the depositional history of the moraine, and its surface has been modified by a Holocene transgressive event. A similar moraine formed on Banquereau but at greater depths.