Report on Klyuchevskoy (Russia) — 11 February-17 February 2015
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 11 February-17 February 2015
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2015. Report on Klyuchevskoy (Russia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 11 February-17 February 2015. Smithsonian Institution and US Geological Survey.
56.056°N, 160.642°E; summit elev. 4754 m
All times are local (unless otherwise noted)
KVERT reported that during 6-13 February a Strombolian and Vulcanian eruption at Klyuchevskoy continued. Incandescence at the summit was visible and bombs were ejected 200-300 m above the crater. Explosions generated ash plumes that rose to altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l.; ashfall was reported in Kozyrevsk Village (50 km W) on 7 February and Klyuchi Village (30 km NNE) on 11 February. A lava flow effused onto the E flank. Satellite images showed a daily, big, bright thermal anomaly over the volcano, and ash plumes drifting about 400 km mainly NW and N at altitudes of 5.5-6.5 km (18,000-21,300 ft) a.s.l.
On 15 February at 1035 the webcam recorded ash plumes rising to altitudes of 6-6.5 km (19,700-21,300 ft) a.s.l. and drifting 74 km E. At 1211, 1347, and 1524 ash plumes rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted 110-232 km E and ESE. The Aviation Color Code was raised to Red. At 1656 ash plumes rose to altitudes of 7.5-7.8 km (24,600-25,600 ft) a.s.l. and drifted 232 km ESE. The Aviation Color Code was lowered to Orange. At 1512 on 16 February ash plumes identified in satellite images rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted 270 km S. The next day, at 0641, 1503, and 1505, ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. and drifted 114-240 km SE.
Geologic Background. Klyuchevskoy (also spelled Kliuchevskoi) is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. It rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of the 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.