SfondoGlacier-covered, 2161-m-high Snowy Mountain, located 15 km NE of Mount Katmai, is the SW-most of a chain of closely spaced volcanoes extending NE along the crest of the Alaska Range. More than 90% of the compound Snowy volcano is mantled by glacial ice, which prompted the naming of the volcano by members of the 1917 Katmai expedition. Two small andesitic-dacitic stratovolcanoes, SW Snowy and NE Snowy, originated about 200,000 years ago. Only NE Snowy has been active during the Holocene. Late-Holocene collapse of this volcano produced a large debris avalanche that traveled to the north and left a large breached crater inside which a blocky lava dome was constructed. Peat beneath an ash layer thought to be associated with the the lava dome was radiocarbon dated at about 250 +/- 70 years ago. No historical eruptive activity has been documented, but fumarolic activity has been observed at NE Snowy. A zone of persistent diffuse shallow seismicity is located on and NW of the volcano.
Smithsonian / GVP volcano information
See also: Sentinel hub | Landsat 8