Kamchatkan and Northern Kurile Volcanic Activity
INFORMATION RELEASE 12-05
Friday, February 18, 2005, 12:20 KST (00:20 UTC)

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 in the volcano's edifice continues. Strombolian
activity into the terminal crater, movement of lava flow into Krestovsky
channel, and ash and gas-steam plumes from the volcano continue.
Klyuchevskoy volcano is dangerous for aviation.

KEMSD GS RAS does not 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 every day and 10 earthquakes of Ml=1.7-2.3 were
registered. A continuous spasmodic volcanic tremor decreased from
A/Tmax=30.5-30.3 x10-6 mps on February 10-11 to 27x10-6 mps on February 12
and to 24.3-25.5 x10-6 mps on February 13-16 (with some decrease of tremor
to 14.6 x10-6 mps on February 15). According to video and visual
observations, the height of ash explosions was about 2,000 - 3,000 m above
the crater (22,200 - 25,400 ft ASL) and ash plumes extended from the
volcano to the south-west on February 12, for 10 km (6.2 mi) to the
south-east on February 13, about 50 km (31 mi) to the north on February 14.
Volcanic bombs rose up to 300-500 m above the terminal crater on February
12-16. 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 12-16. According to data by Yu.Demyanchuk (IVS FED
RAS) after a flight around the volcano with a helicopter Mi-8 on February
16, a lava flow came down to the elevation of 2,500 ASL and the run-out of
a mud flow was about 27 km (16.7 mi). The phreatic bursts into this channel
(at a contact of lava flow with glaciers) were observed on February 12-13.
The gas-steam plumes rose about 600 - 2,500 m above the crater (17,600 -
23,800 ft ASL) on February 12-13 and 15-16, and extended to the west on
February 12, about 15 km (9.3 mi) to the south on February 13, for 30 km
(18.6 mi) to the north on February 15 and for 40 km (24.9 mi) to the
north-west on February 16. Clouds obscured the volcano at other times.
According to satellite data from the USA and Russia, a 2-56-pixel thermal
anomaly was registered at the volcano all week. Ash-gas plumes extending
about 30 km (18.6 mi) on February 13, greater than 100 km (62 mi) to the
south-east on February 14, about 45 km (28 mi) to the south-east and
greater than 90 km (56 mi) to the north-northeast on February 15, for 75 km
(46.6 mi) to the north-west on February 16, 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 8 km or
26,400 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 0.3-0.5 x10-6 mps was registered
all week. According to seismic data, possible ash-gas explosions up to
3,500 - 4,500 m (11,500-14,800 ft.) ASL occurred all week except February
12. Probably three ash explosions up to 5,200 m, 7,500 m and 4,900 m
(17,100; 24,600 and 16,000 ft.) ASL occurred at 14:58, 15:28 and 21:58 UTC
on February 17, respectively. Possible weak ash-gas explosions and hot
avalanches happened all week. According to visual and video data, ash-gas
plumes rose up to 1,500 m above the dome (4,000 m or 13,100 ft ASL) on
February 13-14. A height of gas-steam columns was about 200-300 m above the
dome (2,700-2,800 m or 8,900-9,200 ft. ASL) on February 12-13 and about 800
- 1,500 m above the dome (3,300 - 4,000 m or 8,900 - 13,100 ft ASL) on
February 10 and 14-16. Gas-steam plumes extended from the volcano for 20 km
(12.4 mi) to the south-east on February 13, for 10 km (6.2 mi) to the east
on February 14-15, to the west on February 16. Clouds obscured the volcano
at other times. According to satellite data from the USA and Russia, a
1-37-pixel thermal anomaly was registered at the dome this week. Ash-gas
plumes extending for 20 km (12.4 mi) to the south-east on February 14 and
for 11 km (6.8 mi) to the east on February 15 were noted. Gas-steam plumes
extending about 30 km (18.6 mi) to the south-east on February 13, for
greater than 70 km (43.5 mi) to the south-east on February 14, were
observed. Ash deposits on the snow from the dome to the south-east on
February 13-14, and to the south on February 15, were noted.

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

Volcanic activity probably continues. The danger of a sudden explosion or
series of explosions up to 4 km (16,500 ft.) ASL remains. A local ash fall
within a few tens of km around the volcano is also possible. There is no
seismic data from January 26 till the present.

According to satellite data from the USA and Russia, a 1-pixel thermal
anomaly was registered over the volcano on February 12-13.

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 the 50 - 600
m above the dome (9,700 - 11,500 ft ASL) on February 13-16 and extended
from the volcano for 5 km (3.1 mi) to the west on February 13, for 10 km
(6.2 mi) to the west on February 14 and for 10 km (6.2 mi) to the
north-west on February 16. According to data by Yu.Demyanchuk (IVS FED RAS)
after a flight around the volcano with a helicopter Mi-8 on February 16,
strong gas-steam activity of the central and north-western parts of the
dome was observed. Clouds obscured the volcano at other times. According to
satellite data from the Russia, a 1-3-pixel thermal anomaly was registered
at the dome on February 10 and 12-16.

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

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

According to the data by observers from Severo-Kurilsk, Paramushir Island,
Northern Kurile, a dark-grey column up to 500 m above the crater (1,656 m
or 5,450 ft. ASL) was observed from 20:00 UTC on February 15 till 02:00 on
February 16. A dark-grey plume extended from the volcano 6 km (3.7 mi) to
the east and further a light-grey plume 7 km (4.3 mi) to the south-east.
>From 22:30 till 23:30 UTC on February 16, ash fall together with snow fall
was noted over Vtoroy Kuril'sky Proliv (Second Kurilskan strait). A white
column up to 250 m above the crater (4,600 ft. ASL) was observed from 00:00
till 01:00 UTC on February 17. Clouds obscured the volcano in the other
times. On 08:00 UTC on February 12 and from 23:00 UTC on February 16 till
06:00 UTC on February 17, a strong smell of a hydrogen sulphide was noted
at Severo-Kurilsk. A concentration of a hydrogen sulphide at the city was
about 18.2 and about 48.0 milligram/cubic meter on February 13 and on 
February 17, respectively.

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).