We use a variety of methods.
Probably the largest activity on a cost basis is airborne geophysics. It's a process whereby an aircraft flies and collects measurements from the air. It provides a seamless image of the bedrock below the surface of the ground. We use that to plan our fieldwork, which involves people going in teams out to field areas, setting up a camp, and walking on the ground collecting measurements and observations on the ground, and building a geological map.
That information is supported by laboratory work, which includes analyses that we contract out to private labs--the routine work. Then we do the more cutting-edge research at the Geological Survey of Canada labs when we need answers to very specific questions. For example, it's quite technically challenging to determine the age of rock. They're an important part of the interpretation of the map.
We also analyze surficial materials that the glaciers have left behind for clues to hidden sources of mineralization. Deposits are often covered by sand and gravel till that the glacier has left behind, and we get clues as to where those deposits are through looking at the glacial materials.