Still no consensus on Hemlo deposit

After 10 years of production at the Hemlo gold camp, the geological community may be a lot wiser about the deposits. But several key questions have yet to be answered.

This was the message delivered at a recent workshop on the geology of the northwestern Ontario camp, which opened a 4-day mining symposium organized by the province’s Ministry of Northern Development and Mines (MNDM). The half-day workshop — sponsored by the Toronto Geological Discussion Group, the Mining Industry Technology Council of Canada (MITEC) and the MNDM — brought together individuals and organizations that have been connected with the deposit since its discovery in 1982.

The general theme among the various speakers was that the complex interaction of primary geological features with metamorphism, deformation and alteration has made it difficult to develop a geological model and achieve a consensus on the genesis of the Hemlo deposit.

The workshop was timed to coincide with the start of the new collaborative research initiative by MITEC, which aims to improve the efficiency of mineral exploration for Hemlo-type gold deposits.

The 3-year program is being conducted by a multi-disciplinary team of geoscientists which will include geological consultants, university faculty and government geoscientists. Funding will be supplied by industry and government.

Although the Hemlo workshop was well-attended, attracting about 150 participants, crowds at the remaining sessions appeared to be smaller than in previous years.

Topics discussed in some of the other sessions included land use, raising capital for exploration and development, and highlights from Ontario Geological Survey programs carried out this past summer. The symposium closed with a short course entitled “New Approaches in Targeting Giant Magmatic Ni-Cu-PGE Deposits in Ontario.”