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Fish and Wildlife Service personnel in the field and citizens of Pilot Point reported that on Thursday, 8/13, the usual white steaming from Chiginagak volcano fumaroles changed for a time to puffs of black ash accompanied by a greenish-yellow gas and steam plume rising about 500 to 1000 ft above the volcano. A dusting of black ash was observed on fresh snow on the upper part of the volcano this morning. However, the plume had reverted to white steam. The activity was not substantial enough to be detected by satellite imagery. AVO has no seismic instruments on the volcano but will watch the activity via satellite and in cooperation with ground observers.
Chiginagak Volcano is a 7005-ft-tall (2135 m) snow- and ice-covered symmetric stratovolcano. It is located 110 miles (175 km) south of King Salmon and 37 miles (60 km) southeast of Pilot Point on the Alaska Peninsula. On October 22, 1997, AVO received multiple reports of increased steaming, snowmelt, and sulfur smells. Robust steam plumes have issued from an active fumarole at an elevation of about 5500 feet (1676 m) on the north flank of the volcano since at least 1943 and sulfur deposition in the vicinity of the fumarole discolors the adjacent snow and ice. Reports of historic activity at Chiginagak are poorly documented. Prehistoric domes, young pyroclastic deposits and lava flows occur on the volcano's flanks.
Seismic activity is monitored in real time at 16 volcanoes
in Alaska. Some of these volcanoes may currently display
anomalous seismicity, but they are not considered to be at a dangerous level of unrest.