Global Volcanism Program | Image GVP-06558
Hillman Peak, the westernmost andesitic stratovolcano of Mount Mazama, is partially dissected by Crater Lake caldera. The base of the cone consists of thin andesite lava flows; these are overlain by bedded fall deposits. The upper part of the cone, seen here, consists of andesitic lava flows erupted about 67,000 years ago. The snow-capped peak on the far horizon to the north is Mount Thielsen, a Pleistocene volcano.
Photo by Lee Siebert, 1997 (Smithsonian Institution)