Open AccessSurficial geology, Lac Mistinibi, Quebec, NTS 23-P northeast
Author(s) -
J M Rice,
R C Paulen,
Martin Ross
Publication year - 2017
Language(s) - English
Resource type - Reports
DOI - 10.4095/300656
Subject(s) - geology , deglaciation , meltwater , landform , ice sheet , glacial period , drumlin , geomorphology , tributary , ice stream , physical geography , cryosphere , oceanography , geography , sea ice , cartography
The Lac Mistinibi area is of moderate relief characterized by extensive till blankets and at higher elevations, till veneers and bedrock outcrops. The region was glaciated by the Laurentide Ice Sheet throughout Wisconsin time, east of the Quebec-Labrador icecentre. Two general phases of glacial landform development have occurred in the map-area, with northeast-trending large crag-and-tail landforms and streamlined eastward-trending landforms. These two orientations represent two phases of radial ice flow that have affected the region. Large eskers andrelated glaciofluvial deposits also transect the map sheet along west to east direction, indicative of the westward deglaciation of the region. Abundant, small meltwater channels in the upland areas of the region are evidence of late-phase ice ablation during final deglaciation. Below 488 melevation, the region was inundated by glacial Lake Naskaupi, which occupied the George River basin and its tributaries and winnowed till surfaces.