Kamchatkan and Northern Kurile Volcanic Activity
INFORMATION RELEASE 13-05
Friday, February 25, 2005, 11:30 KST (23:30 UTC on February 24)

The Alaska Volcano Observatory (AVO) received the following release via
e-mail from KVERT (Kamchatkan Volcanic Eruptions Response Team). Kamchatkan
Standard Time (KST) is 21 hours ahead of Alaska Standard 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:
EBEKO: YELLOW
ALAID: GREEN

KLYUCHEVSKOY VOLCANO: 56o03'N, 160o 39'E; Elevation 4,750 m
CURRENT LEVEL OF CONCERN COLOR CODE IS ORANGE.

High seismic activity of the volcano continues. The Strombolian
activity into the terminal crater, a movement of lava into Krestovsky
channel, ash and gas-steam plumes from the volcano are observed.
Klyuchevskoy volcano is dangerous for aviation.

KEMSD GS RAS doesn't have a correct method for Klyuchevskoy volcano to
detect ash plumes using seismic data.

Seismic activity was above background levels all week. A great number
of shallow earthquakes and 36 earthquakes of Ml=1.5-2.1 were
registered. A continuous spasmodic volcanic tremor decreased from
A/Tmax=25.06 x10-6 mps on February 17 to 11.57 x10-6 mps on February
20, increased to 28.68 x10-6 mps on February 21 and decreased a little
to 20.16 x10-6 mps on February 23. According to visual observations, a
height of ash explosions was about 1,000 m above the crater (18,900 ft
ASL) and an ash plume extended from the volcano to the east on
February 21. The Strombolian activity in the crater and the movement
of lava flow into Krestovsky channel on the north-western flank of the
volcano were continuing on February 20-24. There were ash deposits on
Ushkovsky volcano on February 19, and ash falls at Kozyrevsk on
February 19 and Kluchi on February 21. Gas-steam plumes rose about 100
- 1,500 m above the crater (15,900 - 20,500 ft ASL) on February 18,
20-21 and 23, and extended for 30 km (or 18.6 mi) to the west on
February 18, 10 km (or 6.2 mi) to the east on February 20, to the east
and south-southeast on February 21, about 20 km (or 12.4 mi) to the
north on February 23. Clouds obscured the volcano at other times.
According to satellite data from the USA and Russia, a 1-41-pixel
thermal anomaly was registered at the volcano all week. Ash-gas plumes
extending about 200 km (or 124.2 mi) to the west on February 19, about
130 km (or 80.8 mi) to the west and later for 106 km (or 65.9 mi) to
the east on February 20, about 29 km (or 18 mi) to the north-east and
later for 51 km (or 31.7 mi) to the east on February 21, to the
north-west on February 22 were observed.

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

Unrest at the volcano continues. At any time and with little warning,
explosions could produce ash plumes that could rise as high as 10 km or
32,800 ft. ASL, as well as localized ash fall.

Seismic activity was above background levels this week. Weak shallow
earthquakes at a depth 0-5 km beneath the active dome were recorded.
Intermittent spasmodic volcanic tremor of 0.2-0.46 x10-6 mps was registered
all week. According to seismic data, possible ash-gas explosions up to
11,000 m (or 36,100 ft.) ASL occurred at 08:52 UTC on February 19. Probably
ash explosions up to 5,500 -7,500 m (or 18,040 - 24,600 ft.) ASL occurred
on February 17-18 and 21. Possible ash-gas explosions up to 3,700 m - 4,800
(or 12,100 - 15,800 ft.) ASL occurred on February 17, 20 and 23. Possible
weak ash-gas explosions and hot avalanches happened all week. According to
video data, ash-gas plumes rose up to 2,500 and 3,000 m above the dome
(16,400 and 18,100 ft ASL) and extended to the north-east on February 21
and 23, respectively. An extrusive activity of the dome and hot avalanches
accompanying this process were observed on February 22-24. A height of
gas-steam columns was about 300-1000 m above the dome (9,200-11,500 ft.
ASL) on February 19, 21 and 23. A gas-steam plume extended to the
east-northeast on February 21. Clouds obscured the volcano at other times.
According to satellite data from the USA and Russia, a 1-13-pixel thermal
anomaly was registered at the dome this week. A gas-steam plume extending
to the north on February 22 was noted.

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

Seismic activity continues. The danger of a sudden explosion or series of
explosions 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 at background levels on February 21-22. The
number of local shallow events was about 130-160 per day. According to
seismic data, possible ash-gas explosion up to 1500 m above the crater
(or 9,840 ft ASL) occurred on February 21. Possible hot avalanches and
weak ash-gas explosions were on February 21-23. According to satellite
data from the USA and Russia, a 1-4-pixel thermal anomaly was
registered at the volcano on February 18 and 20. Possibly ash deposits
extending 7-8 km (or 4.3-5 mi) to the north-west from the crater were
observed on February 24.

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

Strong volcanic tremor at Klyuchevskoy volcano obscures seismic data for
Bezymianny. According to volcanologists' experience, a growth of lava dome
probably continues.

According to visual observations, gas-steam plumes rose up to 200 m above
the dome (10,000 ft ASL) on February 18 and 20 and extended from the
volcano to the west on February 18, to the east on February 20. Clouds
obscured the volcano at other times. According to satellite data from the
Russia, a 2-pixel thermal anomaly was registered at the dome on February
19-21, and 23.

EBEKO VOLCANO, Paramushir Island, Northern Kurile: 50 41'N, 156 01'E
Elevation 1,156 m
CURRENT LEVEL OF CONCERN COLOR CODE IS YELLOW.

A moderate activity of the volcano continues. A sudden ash explosion up to
3 km (9,840 ft.) ASL are possible.

According to data by observers from Severo-Kurilsk, Paramushir Island
(Leonid and Tatiana Kotenko), on February 18-19, white gas/steam columns 5
m in diameter rose from the two vents (the main at east-north-eastern side
of the active crater and a vent on a place of five small fumarols in 20 m
to the south-east from the main vent) up to 450 m above the crater (1,600 m
or 5,300 ft. ASL). A new lake (10x10 m) on a bottom of the active crater
was observed. No ash deposits on and into the snow near the active crater
was noted. A strong smell of chlorine was noted into the active crater.

PLEASE CONTACT AVO IF YOU HAVE QUESTIONS OR COMMENTS

Olga Girina
Kamchatkan Volcanic Eruptions Response Team
IVS FED RAS, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006 RUSSIA
E-mail: girina@kcs.iks.ru
Tel. (41522) 58627

Svetlana Droznina
Kamchatkan Volcanic Eruptions Response Team
KEMSD GS RAS, Piip Blvd, 9
Petropavlovsk-Kamchatsky, 683006 RUSSIA
E-mail: ssl@emsd.iks.ru
Tel. (41522) 59523

Tom Murray
Scientist-in-Charge, Alaska Volcano Observatory
4200 University Drive
Anchorage, Alaska 99508 USA
E-mail: tlmurray@usgs.gov
Tel. 907-786-7497

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