Quartz sand and kaolinite clay of the James Bay Lowlands, Ontario

CIM Bulletin, Vol. 75, No. 846, 1982

M.A. VOS, Mineral Deposits Section, Ontario Geological Survey, Toronto, Ontario

Cretaceous sands and clays underlie an area of approximately 5,000 km2 in Northern Ontario, southwest of James Bay. The deltaic deposits occur as a wedge of continental sediments to the north of an east-trending fault scarp referred to as the Precambrian Escarpment. They rest on older sedimentary formations of the Moose River Basin (Jurassic, Devonian) and are covered by glacial tills and marine sediments of the Quaternary period. Outcrops are restricted to occasional exposure in the deeply incised riverbeds.In 1975 and 1978, drill programs sponsored by the Ontario Government provided new information on the extent and quality of the deposits. Fourteen holes at approximately 12-km intervals were drilled to a maximum depth of 189 m by re-versed-circulation chip drill methods. Some core was obtained as well. Analytical results show that the thickness of Cretaceous deposits exceeds 100 m in several instances. Abundant kaolinitic clay and quartz sand of glass-grade quality, both unique materials in Ontario, are available in an area where hydroelectricity and lignite resources combine to enhance the energy outlook.
Keywords: Industrial minerals, James Bay Lowland, Sand, Quartz sand, Clay, Kaolinite clay, Moose River Basin, Mattagami Formation, Ceramic tests, Cretaceous deposits.