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 |
5.4/13 | 5.5/19 | 6.5-7 | 111 | IPC GS RAS (Accurate) | 2 |
04-09-16.5 |
42.72 |
45.93 |
10 |
26 |
| 5.7/26 | 7-7.5 | | 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 |
20133287 | 2013-09-17 06:23:53.0 | 41.8 | 45.81 | 10 | 13 | - | 3.5/ 1 | - | Eastern Caucasus | 20133293 | 2013-09-18 00:23:32.0 | 42 | 45.76 | 5 | 23 | - | 3.8/ 2 | 3.5-4 | 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 |
25 | 92 | 20 | 192 |
57 | 316 | 141 | 87 | 147 | 233 |
57 | 4 | IPC GS RAS | |
IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences |
 Figure 4 |
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