Report on Chikurachki (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 Chikurachki (Russia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 11 February-17 February 2015. Smithsonian Institution and US Geological Survey.
50.324°N, 155.461°E; summit elev. 1781 m
All times are local (unless otherwise noted)
According to KVERT, the Tokyo VAAC stated that an eruption at Chikurachki began at 1000 on 16 February. A Support to Aviation Control Service (SACS) notice described a large amount of aerosol near the Northern Kuriles Islands at 1322 that same day. Satellite images detected ash plumes that rose to altitudes of 7-7.5 km (23,000-24,600 ft) a.s.l. and drifted 80 km W. The Aviation Color Code was raised to Orange. At 0641, 1328, and 1635 on 17 February satellite images showed ash plumes rising to altitudes of 3-3.5 km (10,000-11,500 ft) a.s.l. and drifting 95-230 km SW.
Geologic Background. Chikurachki, the highest volcano on Paramushir Island in the northern Kuriles, is actually a relatively small cone constructed on a high Pleistocene volcanic edifice. Oxidized basaltic-to-andesitic scoria deposits covering the upper part of the young cone give it a distinctive red color. Frequent basaltic plinian eruptions have occurred during the Holocene. Lava flows from 1781-m-high Chikurachki reached the sea and form capes on the NW coast; several young lava flows also emerge from beneath the scoria blanket on the eastern flank. The Tatarinov group of six volcanic centers is located immediately to the south of Chikurachki, and the Lomonosov cinder cone group, the source of an early Holocene lava flow that reached the saddle between it and Fuss Peak to the west, lies at the southern end of the N-S-trending Chikurachki-Tatarinov complex. In contrast to the frequently active Chikurachki, the Tatarinov volcanoes are extensively modified by erosion and have a more complex structure. Tephrochronology gives evidence of only one eruption in historical time from Tatarinov, although its southern cone contains a sulfur-encrusted crater with fumaroles that were active along the margin of a crater lake until 1959.