The Peace River region of British Columbia and Alberta is located on the Prairie side of the Rocky Mountains and forms part of the northeast-sloping Alberta Plateau. The area is drained mostly by the Peace River which rises on the west side of the Rockies and its tributaries which flow into Lake Athabasca. From there, the Slave River flows north to become the Mackenzie which finally empties into the Arctic Ocean. So, while most of British Columbia drains westward into the Pacific, this northeast corner is part of the Arctic Drainage.
Geologically, the Peace River region is made up largely of sedimentary rocks, the surface ones being quite recent in origin. The Canadian Shield is visible only at the far eastern end of Lake Athabasca -- otherwise, it is to be found 2 or 3 kilometres down.
The region contains significant deposits of coal, oil and natural gas and these have been exploited commercially for the last few decades.