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Seismic Network of Georgia
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Map of seismic stations installed
in Caucasus region in the beginning of XIX
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| The instrumental period
of seismology has begun in Georgia in the end of XIX century In 1899 the
Tiflis (now Tbilisi) seismic station has been founded in the former Caucasian
district of Russian Empire. The horizontal Rebert-Ellert pendulum has been
installed on the station. The first seismogram has been recorded 6 December
1899. This gives start to the development of seismology in Caucasus. |
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August 11 1903, Earthquake in Greece
36.00N-23.00E.
Recorded in TBILISI Seismic Station on Rebert-Ellert Seismograph
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| After the well-known Shemacha
earthquakes, The Permanent Central Commission of Seismicity (PCCS) in Russia
founded seven seismic stations in the Caucasus region. The horizontal Omori-Boshi
pendulum with mechanical registration was installed in Batumi, Shemaxa,
Axalkalaki, Borgomi, Derbent and Zurnabad in 1903-1908. The Bulletins of
the PCCS also were published. The following moments of phases were indicated
for each earthquakes (mean European time): the beginning of weak oscillations
(flicker) of the pendulum T; the beginning of the oscillations C; the beginning
of the strong oscillations R; amplification (minimum) of the oscillations
M; the end of the oscillation F; and the double-trace amplitude (peak-to-peak)
in millimeters A. About 3971 earthquakes had been recorded during this period.
Most of them were recorded only at one station. The bad quality of the recording
instruments, low velocity of the registration and old identification of
the phase could not allow estimation of the earthquakes' parameters. So
these instrumental observations did not take very important part in the
investigation of the seismicity. (The Earthquakes of the USSR, 1961) |
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In 40-ties the formation of regional
network was finished. From the beginning of 1960 network was equipped
by high sensitive seismographs of different types. At the end of seventies
local seismic networks were established in the region of Enguri Dam (western
part of Greater Caucasus) and Javakheti plateau (South Georgia). In eighties
about 40 seismic stations were operated in Georgia. During the last years
the number of seismic stations has been decreased (from 40 stations in
Georgia in 1991 to 10 in 1997) due to political and economical problems.
In 1998 with the help of Swiss Seismic Survey strong motion network of
Georgia has been created. The seismological database of the institute
of Geophysics includes the information about 57 000 earthquakes.
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Copyright © 2002 GGS. All rights reserved.
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