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The future of gold exploration

Established camps will continue to produce base metal deposits; gold targets increasingly high-grade

by Virginia Heffernan on February 28, 2013 discovery

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Map illustrating exploration maturity in the Flin Flon Greenstone Belt (FFGB). Red shows extensively explored areas near mines. Green shows well explored areas near satellite deposits. Yellow shows under explored areas often under carbonate cover.

 

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Where to explore in the future for gold: smaller, higher-grade deposits are likely to become the focus of future exploration.

Smaller, higher-grade deposits are likely to become the focus of future gold exploration while base metal exploration will continue to tap into established mining camps with the help of new technologies.

Those were the main predictions put forth by Rob Penczak, Goldcorp’s director of exploration (on the gold side) and Kelly Gilmore, HudBay Minerals’ chief geologist (on the base metals side) at a symposium on the future of exploration and mining in Canada. The half-day event hosted by the Toronto Geological Discussion Group (TGDG) drew 96 people (including 24 students from the University of Toronto, Western University and Laurentian University) and featured a range of speakers including Ross Gallinger, executive director of the Prospectors  Developers Association of Canada, and Catherine Farrow, independent consultant and chief technology officer for the former Quadra FNX.

Penczak said the average grade of gold mined worldwide recently dropped to 1.8 grams per tonne from 7.3 gpt in 1979 while the average grade of new gold discoveries is just 0.76 gpt. But he believes high-grade deposits (greater than 5 gpt) will be targets for future exploration because of geographical restrictions, the desire to preserve profit margins, and a smaller environmental footprint that increases the chance of securing community approval and permits.

He likes the odds for gold exploration in higher-grade metamorphic terranes and sedimentary rocks and thinks that by reworking exploration models (e.g., porphyry models in Archean rocks), new opportunities will emerge.

In terms of regions, Penczak is optimistic about northern British Columbia and the Yukon, Nunavut and Baffin Island, the gold camps that straddle the northern Ontario-Manitoba border, the Abitibi greenstone belt, far northern Quebec, and the area surrounding Sudbury.

Gilmore, whose exploration team has had great success in the Flin Flon base metal camp of northern Manitoba over the past decade, expects established mining camps will continue to produce deposits using new technology. He thinks these will be found at both previously unexplored depths (e.g., Lalor and 777 in Flin Flon and Nickel Rim South in Sudbury) and at shallow depths (e.g., Halo Resources’ Lost Lake deposit near Flin Flon). Greenfields exploration will also benefit from technological innovation and knowledge that allows geologists to see under cover.

“At Lalor, we were able to use geophysical technology that could see to 1,000 metres where the favourable horizon was,” he says. “There is a lot of new technology that will deliver new deposits.”

Gold reserves declined steadily from 1996 before rebounding sharply in 2010 as a result of new discoveries and a higher gold price, but both grade and reserves are on the decline for base metal deposits in Canada, increasing the urgency to replace the current supply of producers with exploration success.

But both Penczak and Gilmore have grave concerns about how this exploration will get done under new regulatory threats that are reducing the available landmass to search and creating delays, especially in such highly prospective provinces as Ontario, Manitoba and Quebec.

“One of the main challenges is the change in exploration regulations, which creates uncertainties for juniors,” says Penczak, adding that anything that interferes with junior exploration eventually affects the growth prospects for seniors.“It generally takes three to four years to deliver the first resource, and this could be delayed too.”


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