Seismo-stratigraphy and sedimentology of Holocene sediments off Grande Riviere de la Baleine, southeastern Hudson Bay, Quebec

Abstract

The regional distribution of Holocene sediments of eastern Hudson Bay off the Grande Riviere de la Baleine mouth was mapped using a grid of reflection seismic lines (approximately 300 km long and covering an area of approximately 800 km2) and data from 7 piston cores. Based on the seismic records and piston cores, 4 stratigraphic units overlying the Proterozoic bedrock (unit 1) were defined and interpreted; (unit 2) glacial till deposited by a westward flowing ice sheet, (unit 3) rhythmically bedded clays and silts presumably deposited in glacial Lake Ojibway, (unit 4) postglacial marine muds deposited in the Tyrrell Sea overlain by undifferentiated modern marine muds, and (unit 5) distal fluvio-deltaic sediments from Grande Riviere de la Baleine. Similar stratigraphic units have been described onshore. -from Authors