SVERT reported that on 3 April at 0755 ash from Grozny Group fell in Kurilsk (23 km N) and Kitovy, producing deposits 2-3 mm thick. Cloud cover prevented observations of the volcano. The next day satellite images showed an ash plume that rose 3 km (10,000 ft) a.s.l. and drifted W and NW. The Aviation Color Code remained at Yellow.

All times are local (= UTC - 9 hours [or 8 hours early April-late October])

2013: February | March | April |
2012: August | September |

3 April 2013              Back to Top

SVERT reported that on 3 April at 0755 ash from Grozny Group fell in Kurilsk (23 km N) and Kitovy, producing deposits 2-3 mm thick. Cloud cover prevented observations of the volcano. The next day satellite images showed an ash plume that rose 3 km (10,000 ft) a.s.l. and drifted W and NW. The Aviation Color Code remained at Yellow.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT)

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27 March 2013              Back to Top

Based on analysis of satellite images, the Tokyo VAAC reported that on 30 March a possible eruption from Grozny Group may have produced a plume that rose 2.1 km (7,000 ft) a.s.l. and drifted E. A later VAAC notice stated that ash had dissipated.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC)

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13 February 2013              Back to Top

Based on visual observations, SVERT reported that on 16 February an ash-and-gas plume from Grozny Group rose 3 km a.s.l. The Aviation Color Code was raised to Yellow.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT)

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12 September 2012              Back to Top

Based on visual observations and analyses of satellite imagery, SVERT reported that during 10-17 September fumarolic activity at Grozny Group was at a medium intensity. The Aviation Color Code was lowered to Green.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT)

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5 September 2012              Back to Top

Based on visual observations and analyses of satellite imagery, SVERT reported that during 4-10 September fumarolic activity at Grozny Group increased. The Aviation Color Code remained at Yellow.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT)

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29 August 2012              Back to Top

Based on visual observations and analyses of satellite imagery, SVERT reported that during 23 August-3 September fumarolic activity at Grozny Group increased. The Aviation Color Code remained at Yellow.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT)

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22 August 2012              Back to Top

Based on analyses of satellite imagery, SVERT reported that on 22 August a gas-and-ash plume rose 500 m above Grozny Group and drifted 15 km NE. Fumarolic activity increased during 23-25 August. Observers reported that an ash plume rose to 5 km (16,400 ft) a.s.l. on 25 August. That same day the Tokyo VAAC reported that a possible eruption from Etorofu-Yake-yama, a lava dome of the Grozny Group, may have produced a plume that rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted E.

Sources: Sakhalin Volcanic Eruption Response Team (SVERT) , Tokyo Volcanic Ash Advisory Center (VAAC)

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15 August 2012              Back to Top

According to news reports, Ivan Grozny, one of two volcanoes comprising the Grozny Group, erupted on 16 August, after increased gas emissions from the NE flank were observed the day before. An ash plume rose 1.2 km and caused ashfall in Goryachiye Klyuchi (9 km W) and Kurilsk (25 km away). Residents reported a sulfur dioxide odor. By the afternoon ashfall had ceased and the odor subsided.

Sources: RIA Novosti , Itar-Tass News

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Below is a summary of eruption dates and Volcanic Explosivity Indices (VEI).

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Gorshkov G S, 1958. Kurile Islands. {Catalog of Active Volcanoes of the World and Solfatara Fields}, Rome: IAVCEI, 7: 1-99

Gorshkov G S, 1970. {Volcanism and the Upper Mantle; Investigations in the Kurile Island Arc}. New York: Plenum Publishing Corp, 385 p

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. {IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior}.

Japan Meteorological Agency, 1996. {National Catalogue of the Active Volcanoes in Japan (second edition)}. Tokyo: Japan Meteorological Agency, 502 p (in Japanese)

Nakano S, Yamamoto T, Iwaya T, Itoh J, Takada A, 2001-. {Quaternary Volcanoes of Japan}. Geol Surv Japan, AIST, http://www.aist.go.jp/RIODB/strata/VOL_JP/

Etorofu-Yakeyama (also known as the Grozny Group), in the center of Iturup Island, contains the complex volcanoes of Etorofu-Yakeyama (Ivan Grozny) and Odamoisan (Tebenkov). The former has a 3-3.5 km diameter caldera that is open to the south, where the large, 1158-m-high andesitic extrusion dome was emplaced. Several other lava domes of Holocene age were constructed to the NE; extrusion of these domes has constricted a former lake in the northern side of the caldera to an extremely sinuous shoreline. The forested andesitic Odamoisan lies immediately NE of the Grozny dome complex. The large Machekh crater, which displays strong fumarolic activity, lies immediately south of Odamoisan. Historical eruptions, the first of which took place in 1968, have been restricted to Etorofu-Yakeyama.