Kamchatkan and Northern Kurile Volcanic Activity
INFORMATION RELEASE 23-05
Friday, April 01, 2005, 11:00 KDT (22:00 UTC on March 31)

The Alaska Volcano Observatory (AVO) received the following release via e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). Kamchatkan Daylight Saving Time (KDT) is 21 hours ahead of Alaska Daylight Savings Time. All time and dates are UTC, if not marked specifically.

SUMMARY OF LEVEL OF CONCERN COLOR CODES:

KAMCHATKA:
KLYUCHEVSKOY, SHEVELUCH and KARYMSKY: ORANGE
BEZYMIANNY: YELLOW
TOLBACHIK PLOSKY, KIZIMEN, AVACHINSKY, KORYAKSKY, MUTNOVSKY and GORELY: GREEN

NORTHERN KURILE:
CHIKURACHKI: ORANGE
ALAID, EBEKO: GREEN

KLYUCHEVSKOY VOLCANO: 56°03'N, 160° 39'E; Elevation 4,750 m
CURRENT LEVEL OF CONCERN COLOR CODE: ORANGE

Eruptive activity continues. Explosions from the summit crater could produce ash plumes that reach as high as 7-8 km or 23,000-26,200 ft above sea level and travel many tens or hundreds of kilometers downwind. The current activity of the volcano is dangerous to aviation. The network of seismometers maintained by KEMSD does not allow calibration of ash plume height from the seismic signal.

Seismic activity was above background levels all week. A great number of shallow earthquakes and 27 earthquakes of Ml=1.5-2.1 were recorded. According to visual and video data, ash-gas plumes rising up to 2,500 - 3,000 m above the crater (or 23,800 - 25,400 ft ASL) and extending to the south-east on March 28, and to the north-east on March 29, were observed. Incandescence above the summit crater was noted on March 28. According to the data from AMC, Yelizovo, ash-gas plume rising about 2,000 m above the crater (or 22,200 ft ASL)at 01:20 UTC on March 31, was observed by pilots of aircraft AN-72. Clouds obscured the volcano at other times. According to satellite data from the USA and Russia, a large thermal anomaly was registered at the volcano all week. Ash-gas plumes extending for about 250 km (or 155 mi) to the south-east on March 28, and 270 km (or 168 mi) to the north-east on March 29, for 100 km (or 62 mi) to the north-west on March 31 were noted.

SHEVELUCH VOLCANO: 56°38'N, 161° 19'E; Elevation 3,283 m, the dome
elevation ~2,500 m.
CURRENT LEVEL OF CONCERN COLOR CODE:  ORANGE.

The growth of the Sheveluch lava dome continues. A new extrude block grows at the lava dome. At any time and with little warning, explosions could produce ash plumes that rise as high as 6 km or 20,000 ft. ASL, as well as localized ash fall and hot avalanches. The nearest seismic station from the volcano was destroyed by eruption February 28, 2005.

According to visual and video data, gas-steam plumes rose up to 1,000 – 1,500 m above the dome (11,500 - 13,100 ft ASL) on March 24 and 27-29, and extended for 10 km (or 6.2 mi) to the west on March 27 and to the east on March 29. A new extrude block has grown from March 05 to 28 about 50 m at the south-western part of the lava dome. According to satellite data from the USA and Russia, a thermal anomaly at the dome and large thermal anomaly over the pyroclastic flow were noted all weak. Clouds obscured the volcano at other times.

KARYMSKY VOLCANO: 54° 03'N, 159° 27'E; Elevation 1,486 m.
CURRENT LEVEL OF CONCERN COLOR CODE: ORANGE.

Seismic activity continues. The danger of a sudden explosion or series of explosions of ash up to 4 km (or 16,500 ft.) ASL remains. A local ash fall within a few tens of km around the volcano is also possible.

Seismic activity was above background levels all week. The number of local shallow events was 110-500 per day. Possible ash-gas explosions up to the 1,000 – 1,500 m above the crater (or 8,200 – 9,800 ft ASL) occurred on March 24 and 26. According to visual data by volcanologists on March 29, ash-gas plumes rose up to 1,000 m above the crater (or 8,200 ft ASL) and extended to the east. The explosions occurred from two craters of the summit of the volcano. Ash deposits were observed at the eastern sector of the volcano. According to satellite data from the USA and Russia, a weak thermal anomaly was registered at the volcano on March 25 and 27-29. A possible ash-gas plume extended for 30 km (or 18.7 mi) to the east on March 29. Ash deposits for 14 km (or 8.7 mi) with extension to the south from volcano on March 28 for 12 km (or 7.5 mi) to the south-east on March
29 were noted.

CHIKURACHKI VOLCANO, Paramushir Island, Northern Kurile: 50°19'N, 155°28'E
Elevation 1,816 m
CURRENT LEVEL OF CONCERN COLOR CODE: ORANGE.

Eruptive activity of the volcano was first noted on March 12. Sudden explosions of ash as high as 6 km (19,700 ft.) ASL remain possible. Chikurachki volcano is not monitored with seismic instruments. KVERT has satellite monitoring and occasional visual messages about this volcano.

According to the data by local observers, ash deposits from Chikurachki volcano covered a southern part of Paramushir Island on March 29. According to satellite data from Russia and USA, ash deposits were noted on March 25 and 29. They extended for 19 km (or 11.8 mi) to the south-east on March 29. Clouds obscured the volcano at other times.

BEZYMIANNY VOLCANO: 55° 58'N, 160° 36'E; Elevation 2,895 m
CURRENT LEVEL OF CONCERN COLOR CODE:  YELLOW.

Unrest at the volcano continues. Strong volcanic tremor at nearby Klyuchevskoy volcano makes it difficult to determine seismicity at Bezymianny, and KEMSD GS RAS is unable to accurately determine the state of the volcano. However, based on the persistent thermal anomaly, visual observations from Kozyrevsk, and many years’ worth of volcanologists' experience at this volcano, we infer that lava dome growth continues.

Weak gas-steam plumes were observed on March 24 and 27-28. They extended to the north-east on March 24, to the south on March 27, to the east and south-east on March 28. Clouds obscured the volcano at other times. According to satellite data from the Russia, a weak thermal anomaly was registered at the dome all week except March 26-27.

PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS

Olga Girina, KVERT, IVS FED RAS
E-mail: girina@kcs.iks.ru
Tel. (41522) 58627

Svetlana Droznina, KVERT, KEMSD GS RAS
E-mail: ssl@emsd.iks.ru
Tel. (41522) 59523

Tom Murray, Scientist-in-Charge, AVO
E-mail: tlmurray@usgs.gov
Tel. 907-786-7497

The Kamchatkan Volcanic Eruption Response Team (KVERT) is a cooperative program of the Alaska Volcano Observatory (AVO, USA), the Institute of Volcanology and Seismology (IVS) FED RAS and the Kamchatkan Experimental and Methodical Seismological Department (KEMSD) GS RAS (Russia).