Late Wisconsinan McConnell glaciation of the Big Salmon Range, Yukon.

The late Wisconsinan McConnell glaciation of the Big Salmon Range in the Pelly Mountains consisted of a four-phase ice-flow history. Phase 1 ice-flow consisted of local alpine glaciers advancing to the mountain front. During phase 2, or glacial maximum, the Cassiar lobe of the Cordilleran ice sheet advanced to the northwest and overtopped the range. Retreat of the Cassiar lobe during phase 3 of the glaciation resulted in ponding of meltwater in eastern drainage basins. The meltwater spilled over into western basins and caused significant erosion of surficial sediments. Phase 4 of the glaciation is marked by a limited late-glacial readvance of local alpine glaciers. This glacial history has several important implications for mineral and placer exploration in the area.