Report on Chirpoi (Russia) — January 2017
Bulletin of the Global Volcanism Network, vol. 42, no. 1 (January 2017)
Managing Editor: Edward Venzke
Chirpoi (Russia) Chirpoi's Snow cone erupts 11 November 2012; continued activity through October 2016
Please cite this report as:
Global Volcanism Program, 2017. Report on Chirpoi (Russia). In: Venzke, E (ed.), Bulletin of the Global Volcanism Network, 42:1. Smithsonian Institution.
46.525°N, 150.875°E; summit elev. 742 m
All times are local (unless otherwise noted)
The first recorded eruption in 30 years at Russia's Chirpoi volcano was initially detected on 11 November 2012 by MODIS infrared satellite data and captured by the MODVOLC thermal alert system. The Sakhalin Volcanic Eruption Response Team (SVERT) reported satellite images that detected thermal anomalies over Snow, a volcanic crater on the S end of Chirpoi Island, beginning on 20 November 2012 (BGVN 38:12), which they interpreted as a possible lava flow on the SE flank. Sparse satellite observations by SVERT, MIROVA and MODVOLC thermal anomaly information, a single report from the Tokyo Volcanic Ash Advisory Center (VAAC), and a site visit to this remote location in the Kuril Islands in the western Pacific Ocean together suggest nearly continuous activity at Snow through mid-October 2016.
Activity during November 2012-April 2013. Continuous reports of activity between November 2012 and April 2013 began with strong MODVOLC thermal anomalies from MODIS satellite data first recorded on 11 November local time, followed by a report of thermal anomalies detected from SVERT on 20 November. Strong thermal anomalies were reported by MODVOLC for 12 days during November and nine days during December 2012, after which they did not appear again until July 2013. However, SVERT reported thermal anomalies in satellite data almost weekly through 26 April 2013. They also observed steam-and-gas emissions in satellite data a number of times between 15 December 2012 and 5 March 2013.
Activity during July 2013-June 2014. After about a 10 week break between thermal anomaly observations, the MODVOLC pixels reappeared on 8 July 2013, and SVERT reported a thermal anomaly on 14 July 2013 suggesting a new period of lava effusion. The MODVOLC anomalies were intermittent with only three in July, one each in August and September, and two in October 2013; they then disappeared until March 2014. A single MODVOLC thermal anomaly was recorded on 10 March 2014, one appeared on 2 June and two appeared on 25 June 2014.
SVERT reported anomalies twice in July 2013, three times in August and once on 1 September before picking up again in November. SVERT reported thermal anomalies every week in November 2013, and most weeks through the first week in May 2014. After weak anomalies during 2-4 June 2014, SVERT inferred cooling lava flows and lowered the Alert Level from Yellow to Green.
Steam-and-gas emissions were reported by SVERT only between 23 July and 12 August 2013, and not again until late October. Gas-and-steam emissions were common between 22 October and 25 November 2013 when a plume was observed in satellite imagery drifting 90 km SE, after which plumes were not observed until 15 March 2014. Twice in late March (20 and 27) steam-and-gas plumes were detected drifting SE (150 and 50 km). After 13 April 2014, plumes were not detected again until September.
Activity during August 2014-October 2016. Although SVERT kept the Alert Level at Green until 4 September 2014 when they raised it back to Yellow, MODVOLC thermal alert pixels in late June (two on the 25th) and on 10 August, suggest possible continued activity during the summer. When skies were clear, SVERT again detected thermal anomalies in satellite data beginning on 1 September 2014 and continuing most weeks until 8 June 2015. MODVOLC recorded thermal anomalies on 2 and 22 September, and 22 October 2014, but then was quiet until a strong signal reappeared in April 2015 with six days of multiple anomalies recorded during the month, and five days with anomalies in May. During this interval from September 2014 to June 2015, steam-and-gas plumes were reported twice each in September 2014, February, March, and April 2015, and on 25 May 2015.
While no data is available from SVERT between 9 June and 11 November 2015, the Aviation Color Code remained at Yellow, and single MODVOLC thermal alert pixels were recorded on 28 June, 19 and 30 July, two on 7 September, and one each on 5 October, 3 November, and 19 November 2015, suggesting some type of continued heat source such as a lava flow. In addition, MIROVA records for 2015 provide the strongest evidence for ongoing low-to-moderate volcanic activity throughout 2015 (figure 2).
Visual confirmation of an effusive eruption at Chirpoi was made in October 2015. The website Volcano Discovery reported that "Passengers on board a Russian cruise ship (Ponant) documented the recent … eruption of Snow volcano. When passing the island in October 2015, lava flows were actively reaching the sea, creating spectacular littoral explosions." (figure 3). A video of the event from the cruise ship is also posted on the website.
SVERT reports were available again beginning in November 2015 and they reported that satellite images revealed thermal anomalies almost weekly from 11 November through 10 August 2016. They lowered the Alert Level to Green on 29 August 2016. MODVOLC thermal anomaly data was sparse in 2016 with only three reports of single anomalies on 5 February, 20 May, and 12 June 2016. Reports of steam-and-gas plumes observed in satellite imagery from SVERT were made on 12 and 14 November 2015, 24 March, and 20 and 23 April 2016. A plume that may have contained minor ash was observed by SVERT in satellite data drifting SW on 16 July, and one drifting 90 km N was noted during 22-24 July.
The Tokyo VAAC reported a possible eruption observed on satellite imagery at 1300 UTM on 6 March 2016 with a plume rising to 6.1 km altitude and drifting E. MIROVA data for 2016 again seems to confirm ongoing low to moderate thermally anomalous activity at Chirpoi until the middle of October when Radiative Power levels drop below 0.5 Watts VRP (figure 2).
Geologic Background. Chirpoi, a small island lying between the larger islands of Simushir and Urup, contains a half dozen volcanic edifices constructed within an 8-9 km wide, partially submerged caldera. The southern rim of the caldera is exposed on nearby Brat Chirpoev Island. The symmetrical Cherny volcano, which forms the 691 m high point of the island, erupted twice during the 18th and 19th centuries. The youngest volcano, Snow, originated between 1770 and 1810. It is composed almost entirely of lava flows, many of which have reached the sea on the southern coast. No historical eruptions are known from 742-m-high Brat Chirpoev, but its youthful morphology suggests recent strombolian activity.
Information Contacts: Sakhalin Volcanic Eruption Response Team (SVERT), Institute of Marine Geology and Geophysics, Far Eastern Branch, Russian Academy of Science, Nauki st., 1B, Yuzhno-Sakhalinsk, Russia, 693022 (URL: http://www.imgg.ru/en/ , http://www.imgg.ru/ru/svert/reports ); Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://hotspot.higp.hawaii.edu/; http://modis.higp.hawaii.edu/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/ ); Volcano Discovery (URL: http://www.volcanodiscovery.com/chirpoi/news/55254/Chirpoi-volcano-Kurile-Islands-Russia-video-of-lava-entering-the-sea.html); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/ ).