Report on Gorely (Russia) — September 1996
Bulletin of the Global Volcanism Network, vol. 21, no. 9 (September 1996)
Managing Editor: Richard Wunderman.
Gorely (Russia) Seismic activity increases with over 20 earthquakes recorded on 19 September
Please cite this report as:
Global Volcanism Program, 1996. Report on Gorely (Russia). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 21:9. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199609-300070.
52.559°N, 158.03°E; summit elev. 1799 m
All times are local (unless otherwise noted)
On 19 September seismic activity increased and more than 20 earthquakes (M <= 1.8) were recorded beneath Gorely. However, no sign of eruptive activity was observed around the crater on 20 September. During 23-30 September seismicity returned to background levels.
Geologic Background. Gorely volcano consists of five small overlapping stratovolcanoes constructed along a WNW-ESE line within a large 9 x 13.5 km caldera. The caldera formed about 38,000-40,000 years ago accompanied by the eruption of about 100 km3 of tephra. The massive complex includes 11 summit and 30 flank craters, some of which contain acid or freshwater crater lakes; three major rift zones cut the complex. Another Holocene stratovolcano is located on the SW flank. Activity during the Holocene was characterized by frequent mild-to-moderate explosive eruptions along with a half dozen episodes of major lava extrusion. Early Holocene explosive activity, along with lava flows filled in much of the caldera. Quiescent periods became longer between 6000 and 2000 years ago, after which the activity was mainly explosive. About 600-650 years ago intermittent strong explosions and lava flow effusion accompanied frequent mild eruptions. Historical eruptions have consisted of moderate Vulcanian and phreatic explosions.
Information Contacts: Tom Miller, Alaska Volcano Observatory (AVO), 4200 University Drive, Anchorage, AK 99508-4667, USA; Vladimir Kirianov, Kamchatka Volcanic Eruptions Response Team (KVERT), Institute of Volcanic Geology and Geochemistry, Piip Ave. 9, Petropavlovsk-Kamchatsky, 683006, Russia.