The Kamchatka Volcanic Eruption Response Team (KVERT) has provided notices and reports of volcanic activity since 1993. Kamchatka is part of a Pacific ring of volcanoes with 29 active volcanoes. These volcanoes produce explosive volcanic ash clouds every 2 or 3 years that spread across major international air routes between North America and Asia. The staff of KVERT, in collaboration with Kamchatkan Experimental and Methodical Seismological Department (KEMSD) of the Russian Academy of Sciences and the Institute of Volcanology and Seismology (IVS), monitors active volcanoes of Kamchatka seismically. This is done by visual observations and video, utilizing satellite images for ash cloud detection and tracking of thermal anomalies. As of 2003, there were 28 remote seismic stations operating at 11 of the most active volcanoes in Kamchatka and the North Kurile Islands. Three volcanoes, Bezymyanny, Sheveluch and Kyuchevskoy are being monitored by a video-camera system. Real-time images of these three volcanoes are available on the Internet, at http://emsd.iks.ru. Seismic observations are used universally to discover the start of volcano unrest and to recognize volcanic blasts of volcanoes obscured by weather. KVET examines data from U.S. and Japanese meteorological satellites, in cooperation with the Alaska Volcano Observatory. A number of times a day, images from GOES (Geostationary Operational Environmental Satellites), GMS (Geostationary Meteorological Satellite) and polar-orbiting satellites carrying AVHRR (Advanced Very High Resolution Radiometer) are examined for volcanic activity.
The most active volcanoes of the world are located in Kamchatka. Annually from 3 to 5 explosive eruptions are observed in this region. For many years of research the Institute of Volcanology and Seismology, Far Eastern Branch of the Russian Academy of Sciences (IVS) and Kamchatkan Branch Geophysical Survey of the Russian Academy of Sciences (KBGS) has stored unique information resources on Kamchatka volcanoes that permits to monitor volcanic hazards on the real-time basis.
Starting from 1992, hydrogeochemical data have been collected with a mean sampling
frequency of three days in the form of the pH value and of the most common ions and
gases in the groundwater of a deep well located in the capital city Petropavlovsk of
Kamchatka (Russia). On January 1, 1996 the Karymsky volcano, located 100 km far
from the well in north-northeaster direction, started a strong eruption. Simultaneously
a large (M = 6.9) earthquake occurred in the Karymsky area. On December 5, 1997 a
very large (M = 7.7) earthquake occurred offshore, 350 km far from the well, in north-
easter direction. The raw trends of the hydrogeochemical parameters at the well reveal
clear variations occurred for both of the previous events. In the first case, the variations
are defined by a clear premonitory phase; in the second one they are post seismic vari-
ations and some permanent disturbance in the chemistry of the water appears. During
the measurements time other large (M=7.0-7.3) earthquakes occurred at distances less
than 250 km from the previous well in south and in east direction. On these occa-
sions none evident variation appears in the previous trends. The phenomenology we
pointed out reveals a strict structural connection between the Petropavlovsk area and
the north-northeaster zone. At the same time it confirms that the appearance of precursors in hydrogeochemical parameters can be anisotropic in space. According to our
opinion, this anisotropy could be valid also for other different parameters used in the
research on earthquake precursors.
The Spitak and Karymsky earthquakes occurred with M46.9 in
Armenia and in Kamchatka (Russia), respectively. As regards the Spitak earthquake, we analysed the groundwater helium content data collected by three Georgian and one Armenian measurement sites; as regards the Karymsky earthquake, we analysed the groundwater helium content data collected by two measurement sites in Kamchatka. The first analysis has pointed out that precursory anomalies appeared in the northern area with respect to the Spitak epicentre; on the
contrary, only co-post seismic anomalies were revealed in the southern area. As regards the Karymsky earthquake, no pre-co-post seismic variation in the groundwater helium content was revealed at both the measurement sites. The
analysis of other hydrogeochemical parameters, collected in these sites, revealed that one site does not show any anomaly; on the contrary, at the other measurement site clear preseimic anomalies appeared in some hydrogeochemical parameters. A possible explanation of the quoted results is presented.
Abstract. For many years flow-rate, temperature, ions and gases content data have been collected from a natural spring located in the Koryakskiy volcano area (Kamchatka, Russia). We have investigated the correlations between the hydrogeochemical data and the areal seismicity represented by the ks values (ks is a function of magnitude and hypocentral distance) of the earthquakes. At first we smoothed the raw hydrogeochemical data using a semi-triangle weight function. Then we compared the trends of each smoothed hydrogeochemical parameter with the ks trend using a running cross-correlation function with a maximum lag of ± 30 days and the main result was that, sometimes, we found 0.7–0.4 cross-correlation coefficients with no lag for flow rate and with + (10 – 15) days lags for some ion and gas contents. The correlation is positive, i.e. flow rate and ion and gas contents increase when ks increases. This phenomenology could be explained by an underground water pumping produced by some earthquake. We advance the hypothesis that this pumping could be the response of the viscoelastic underground medium of the Koryakskiy volcano to seismic waves. So, sometimes, the supply of elastic energy of the earthquakes may provide the trigger to a catastrophic nucleation of bubbles of this material producing a new melt with a lower density which will tend to expand and cause a pressure increase. This pressure produces a more intensive circulation of underground water and an anomalous increase of the flow rate and subsequently anomalous increases in groundwater ions and gases content.
