Williams Crater 2. Aerial view east-northeast over Williams Crater cinder cone (basaltic andesite, unit bw; ca. 35 ka) and Hillman Peak (andesite, unit ah; 61±8 ka) on the west rim of Crater Lake caldera. Mingled basaltic andesite and dacite lava (unit mw; forested) issued from west (left) base of cinder cone, crater, and a tiny dome near Rim Drive. Treeless ground is mainly underlain by fine-grained, lithic- and crystal-rich ignimbrite (unit cu) and proximal lithic breccia (unit cb) of the climactic eruption. Buff-colored slope on top of rhyodacite flow of Llao Rock (unit rh; upper left) is the pumice-fall deposit of the climactic eruption (unit cp). Three rounded, forested hills beyond caldera rim in center distance are pre-Mazama rhyodacite domes: left to right, Bear Butte, Lookout Butte, and Scout Hill (unit rpb). Photograph by Charles R. Bacon. |