Quaternary sediment maps of the Gulf of St. Lawrence

This open file report describes the results of high resolution geophysical and geological surveys of the Gulf of St. Lawrence (enclosure 2) conducted in 1989 (Baffin 89-008, Dawson 89-007) and 1990 (Hudson 90-028, 90-031 ). Data collected as early as 1969 have also been incorporated. Regional information on the surficial and bedrock geology of the entire Gulf was obtained. This report illustrates major features of the surficial sediments and geomorphology of the region with 42 stratigraphic sections, 21 figures and 15 maps. A comparison of the acoustic character of the seismic reflection profiles from the Gulf of St. Lawrence shows many similarities to other well studied areas off the east coast of Canada and the St. Lawrence Estuary. Based on these similarities we tentatively interpret the presence of till(s), glaciomarine sediments and postglacial muds and sands. The architecture of the Quaternary deposits is illustrated by the seismic sections and isopach map panels. This three dimensional data set is used to interpret the glacial and postglacial depositional processes in the region. This report is primarily intended to provide a stratigraphic framework for ongoing multidisciplinary studies of the glacial and post glacial history of the area.