Report on Korovin (United States) — 1 November-7 November 2006
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 November-7 November 2006
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2006. Report on Korovin (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 1 November-7 November 2006. Smithsonian Institution and US Geological Survey.
52.381°N, 174.166°W; summit elev. 1518 m
All times are local (unless otherwise noted)
The number of daily earthquakes increased in July and remained elevated into November. Episodes of volcanic tremor that first occurred in September increased in number, strength, and duration in the past several weeks. On 28 October, residents of Atka observed steam emissions to many hundreds of meters above the summit. On 6 November, the AVO raised the Aviation Level of Concern Color Code to Yellow and the Volcanic Alert Level to Advisory due to the high seismicity and steam emissions.
Geologic Background. Korovin, the most frequently active volcano of the large volcanic complex at the NE tip of Atka Island, contains a 1533-m-high double summit with two craters located along a NW-SE line. The NW summit has a small crater, but the 1-km-wide crater of the SE cone has an unusual, open cylindrical vent of widely variable depth that sometimes contains a crater lake or a high magma column. A fresh-looking cinder cone lies on the flank of partially dissected Konia volcano, located on the SE flank. The volcano is dominantly basaltic in composition, although some late-stage dacitic lava flows are present on both Korovin and Konia.