Sept/Oct 2006

40/40 Hindsight – GeoSoc field trip to Vancouver Island

Studying Vancouver Island geology map at Campbell Lake

On October 28, 1966, CIM organized a field trip to a new mining operation in the heart of Strathcona Park, central Vancouver Island. At that time, “Total Reasonably Assured Ore Reserve” at Myra Falls mine was 2,053,980 short tons grading 10.01% Zn, 2.19% Cu, 1.10% Pb, 0.06 opt Au, 2.64 opt Ag.

On May 19, 2006—40 years and 40 million tonnes of total resource later - CIM returned just as the Myra Falls Operations of NVI Mining Ltd. is celebrating a new era of enhanced profitability and renewed exploration potential, as their gold recovery circuit processes bonanza grade ore from newly recognized precious metal ore zones.

Twelve field trip participants boarded a bus following the CIM Conference and Exhibition to catch the ferry to Vancouver Island for a sunset cruise to Nanaimo (famous for its bars) and an evening run up the coast to Campbell River, “salmon capital of the world.”

The geology tour started early the next morning with a visit to the nearby Quinsam Coal Operations of Hillsborough Resources Ltd. Jim McMillan and Cale Dubois presented an overview of mine geology, production, and reserves. Gwyneth Cathyl-Bickford reviewed the regional geology plus the strategy and results of their ongoing regional exploration program, and illustrated with exploration drillcore. This mine initially developed, and continues to produce from, a main coal seam averaging nine feet in thickness, but recent drilling has intersected a 15-foot-thick coal seam under the mine access road, ensuring a long and profitable mine life.

The road tour continued 80 kilometres along the shore of Buttle Lake, nestled among Strathcona Park’s snowcapped peaks. Roadcuts expose representative strata from the main units comprising the stratigraphic record of Vancouver Island.

Upon returning to the ‘Austrian Chalet’ in Campbell River to join members of the Vancouver Island Exploration Group (VIX), plus mine staff from the Quinsam and the Myra Falls mines, 31 people enjoyed dinner and a four-hour seminar on the geology, mineral deposits, and exploration potential of Vancouver Island.

Dani Alldrick, British Columbia Geological Survey, presented an overview of the geology and exploration potential of Vancouver Island.

Finley Bakker, exploration manager at Myra Falls Operations, described the mine geology and the characteristics and variability among the many Kuroko-style VMS ore deposits at Myra Falls. Combined production over the past 40 years exceeds 25 million tonnes.

Laura Hubbard, mine geologist at Myra Falls, reviewed the precious metal content and mineralogy of the conventional VMS ore zones at the mine, then profiled the characteristics and grades of the precious metal-rich VMS deposits and the spectacular new precious metal zones at Myra Falls that are separate from the main VMS lenses. The mine has recovered 15,000 ounces of gold in the past six months from their BC-made Nelson concentrator circuit. Pride-of-place in the geology office is reserved for the assay certificate for a grab sample from a precious metal-rich zone that returned 5,000 g/t Ag and 5,300 g/t Au.

Jim McMillan presented a detailed geological picture of the Quinsam Coal mine, emphasizing that, although the coal beds dip gently to the east, structural breaks, in the form of various fault sets, can turn sections of their main coal seam into blocks that are locally too costly or too dangerous to mine. Careful underground mapping and regular communication with all production personnel are the keys to safety and profitability.

Jacques Houle described geology and exploration potential of the Macktush Au-Ag-Cu veins in the Port Alberni area, under active exploration by SYMC Resources Ltd.

The next morning saw an early start back into the heart of Strathcona Park for an underground tour at Myra Falls Operations. Laura Hubbard led the group to type examples of conventional VMS ore, precious metal-rich VMS ore, and the newly delineated high-grade precious metal ore zones. Loaded with big sample bags and bigger grins, the tour group managed a final surface stop at the Myra Falls coreshed where Cliff Pearson guided them through their rock sample and core library of ore, country rock, and alteration.

The tour bus raced back to Nanaimo, arriving at the ferry terminal with 90 seconds to spare. Onboard, the tour group had a final opportunity to compare notes, enjoy another dinner with a sunlit view of the Coast Mountains, and ruminate on whether the ferry was travelling toward the continent, or continental drift was transporting North America toward the ferry.

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