Information message about sensitive earthquake in Georgia-Russia border region, September 17, 2013

     The sensitive earthquake with М=5.5 has occurred on September 17, 2013 at 04:09 GMT (08:09 Moscow time) in Georgia-Russia border region.
     Parameters of the earthquake have been determined in the Alert Service (AS) of Information Processing Center (IPC) of Geophysical Survey of RAS in Obninsk with station data obtained from digital and analog seismic stations of Russia, countries of CIS and from abroad. Alert message on this earthquake has been delivered in 11 min after registration to the Ministry of Emergency of the Russian Federation (EMERCOM).
     Preliminary processing has been done with data from 26 stations, accurate processing - with data 58 stations.
     Fig. 1 presents fragments of records obtained from digital stations Botlikh(∆ 0.7º), Groznyy( ∆ 1.1º), Derbent (∆ 1.9º), Garni (∆ 2.2º), Kislovodsk (∆ 3º). Fig. 2 presents fragments of records obtained from digital stations Obninsk (∆ 14.4º), Borovoe (∆ 19.7º), Vasula (∆ 20.3º), Kurchatov (∆ 24.1º), Lovozero (∆ 26.6º).

Figure 1
 

Figure 2
 
     IPC GS RAS also has obtained information with parameters of this event from some seismological centers, these data are given in table 1:
Table 1
NN Time in origin h-min-s (GMT) Lat degr. Lon degr. Depth km N s/st Ms/ N mb/ N I0 calc GAP Center
1 04-09-12.9 42.07 45.8  15  56  5.4/135.5/196.5-7 111 IPC GS RAS (Accurate)
2 04-09-16.5 42.72 45.93  10  26   5.7/267-7.5 IPC GS RAS (Preliminary)
3 04-09-13.9 42.131 45.798  2  265  Mw 5.1   17 CSEM
4 04-09-14.9 42.112 45.834  16.32  99   5.4   53 NEIC
5 04-08-43.4 42.06 45.701  1    Ml 5   13 UNSSPG
6 04-09-12.9 41.971 45.731  7.9  28  Ml 5.8   266 RSSC
  • IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences
  • CSEM - European - Mediterranean seismological center
  • NEIC - National Earthquakes Information Center of US Geological Service
  • UNSSPG - United National Survey for Seismic Protection , Georgia
  • RSSC - Republican Seismic Survey Center of Azerbaijan National Academy of Sciences
    • Epicenter
         Fig. 3 presnts epicenter of this earthquake with yellow star, it's origin was located in Georgia-Russia border region at the depth of 15 km, 75 km S-W of Botlikh, Russia, and 92 km E-N-E of Tbilisi, the Capital Georgia.

    Figure 3
    Aftershock
         GS RAS registered 2 aftershocks with М>=3.5 within the day after the main shock.
    N Date   &   Time (GMT)
    yy-mm-dd hh:mm:sec    		 Lat
    degr.    		 Lon
    degr.    		 Depth
    km    		 N
    station    		 Ms/ N mb/ N Io
    calc.    		 Region
    201332872013-09-17 06:23:53.041.845.811013-3.5/ 1-Eastern Caucasus
    201332932013-09-18 00:23:32.04245.76523-3.8/ 23.5-4 Eastern Caucasus
    Macroseismic manifestations
         According to GS RAS this earthquake was felt in Botlikh with intensity 3-4, in Makhachkala, Dylym, Mamedkala and Temirgoe with intensity 2-3 MSK. According to RIA-Novosti this earthquake has damaged only roofs in a few houses in Kvareli, Georgia. It was felt in Tbilisi, in the settlements located in the Georgia-Azerbaijan border region with intensity 3-4 and on the territory of Armenia in Noemberian and Idjevan with intensity 3.
    Focal mechanism and seismic moment of the earthquake
         Focal mechanism of this earthquake was calculated in IPC GS RAS with signs of initial arrivals of P waves at 30 stations, including 21 stations which registered the waves of compression (plus signs) and 9 stations which registered the waves of extension (minus signs). These stations are located in the interval of epicentral distances 0–72º and are scattered evenly along the azimuths. Focal mechanism solution of the origin in stereographic projection at the lower hemisphere is presented at figure 4, elements of mechanism are presented in table 2. The earthquake has occurred under the action of close in value stresses of compression oriented to the south, and stresses of extension oriented to the east. Both nodal planes are steeply dipping, however NP1 is more steeply dipping (DP=87º) and oriented south-east (STK=141º) while NP2 plane is rather flat (DP=57º) and oriented south-west (STK=233º). The type of motion along both planes – slips with overthrust components. For NP1 this is right side slip, for NP2 –left side slip. Seismic moment of the earthquake was obtained in IPC GS RAS with Р-wave spectra registered at «Talaya» (∆39.6) station, Мо=3.3*10**17 N*m, Mw=5.6.
    Table 2
    Axes of main strengths Nodal planes Center
    T P N NP1 NP2
    Pl Azm Pl Azm Pl Azm Stk Dp Slip Stk Dp Slip
    259220192 5731614187147233 574IPC GS RAS
  • IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences

    • Figure 4


    News | Catalogs | Wave Forms | Alert Service | Software | Links | Srtucture | Publications | Conferences | Announce | About
    © FRC GS RAS 1993-2018