Between one and two million years ago, during the glaciation at the beginning of the Pleistocene Era, huge ice sheets scraped the Northwest Territories, eroding away rocks, particularly soft rocks like the top of kimberlites.
The last glacier melted 10,000 years ago. When they melted, glaciers left behind, in the glacial till they transported, tiny or microscopic pieces of garnets, ilmenites, chromites etc., called indicators minerals because those minerals are usually found in diamondiferous kimberlites. Geologists have then to follow the clues left by the glaciers back to the source kimberlite. |
