Text Description: |
Early Dacite Domes and Associated Flows. Three hornblende dacite domes (1, 2, 3) on east flank of Mount Drum were apparently erupted early in dome-building stage of second cycle of volcanic activity and may represent a distinct phase of second cycle associated with cone-building two-pyroxene andesite and dacite flows (Qzaf). All domes have been dissected by erosion, and dome 1, an extensive dome-flow complex with a surface area greater than 10 sq km, is overlain by widespread deposits of glacial drift (Qog). |