A preliminary assessment of unconsolidated mineral resources in the Canadian offshore

CIM Bulletin, Vol. 77, No. 869, 1984

PETER B. HALE, Ocean Mining Division, Canada Oil and Gas Lands Administration, Ottawa, Ontario, K1A OE4, PATRICK MCLAREN, Geological Survey of Canada, Pacific Geoscience Centre, Sidney, B.C.

Canada, with one of the largest continental shelf areas in the world, has done little to evaluate its offshore unconsolidated mineral resources which include heavy minerals (gold, chromite, rutile etc.) and industrial minerals (silica sand and aggregates). During glaciation much of the continental shelf was covered with an ice sheet and later subaerially exposed with the result that glacial, glaciomarine and fluvial processes deposited sediments that may contain heavy minerals derived from on/and locations. With rising sea-levels, beach and near-shore processes may have served to concentrate heavy minerals by winnowing and removing the lighter mineral components. These potentially valuable resources can be found with suitable exploration techniques such as seismic profiling and bottom sampling. Gold deposits are known to exist off the coast of Nova Scotia, and on the basis of former beach mining, gold deposits probably occur off Vancouver Island and the Queen Charlotte Islands. Large deposits of silica sand occur near the Madeleine Islands and it appears likely that supplies of marine aggregates are present close to urban markets or sites of future mega-projects such as oil field developments. This paper, which is based upon a review of literature and consultation with members of the Department of Energy, Mines and Resources' Coordinating Committee on Ocean Mining (DCOM), is the first step in assessing the Canadian offshore for its resource potential with respect to quantified deposits, known and speculative mineral occurrences. Although this is a subjective evaluation, the potential appears promising. A more detailed resource inventory is required to provide a more certain assessment.

Keywords: Offshore mining, Mineral resources, Industrial minerals, Placer minerals, Canadian offshore