Report on Bezymianny (Russia) — 1 November-7 November 2000
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
1 November-7 November 2000
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2000. Report on Bezymianny (Russia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 1 November-7 November 2000. Smithsonian Institution and US Geological Survey.
55.972°N, 160.595°E; summit elev. 2882 m
All times are local (unless otherwise noted)
KVERT reported that an increase in seismicity began at Bezymianny on 30 October, reaching its highest level during 0320 to 0400 on 2 November. At 0626 AVHHR imagery showed that an ash plume from the volcano reached ~6.5 km a.s.l., initially extending to 50 km W of the volcano, then 130 km to the SW. At 1200 seismicity began to decrease. In addition to the AVHHR imagery, the Tokyo VAAC detected the ash cloud in GMS-5 imagery until 2332. Small ash clouds were visible on AVHRR imagery during 2 and 3 November. KVERT lowered the Level of Concern Color Code at the volcano from Orange to Yellow.
Geological Summary. The modern Bezymianny, much smaller than its massive neighbors Kamen and Kliuchevskoi on the Kamchatka Peninsula, was formed about 4,700 years ago over a late-Pleistocene lava-dome complex and an ancestral edifice built about 11,000-7,000 years ago. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of St. Helens in 1980, produced a large open crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater.