Information message about the appreciable earthquake in Azerbaijan on September 4, 2015 года

     The appreciable earthquake has occurred on September 4, 2015 at 4:49 GMT (7:49 Moscow time) in Azerbaijan M=5.2
     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 22 stations, accurate processing - with data 57 stations.
     Fig. 1 presents fragments of records obtained from digital stations Garni (∆ 2.4º), Nalchik (∆ 3.9º), Khabaz (∆ 4.4º), Kislovodsk (∆ 4.7º), Sochi (∆ 6.4º). Fig. 2 presents fragments of records obtained from digital stations Keshkin Array (∆ 10.7º), Belogornoe (∆ 11.4º), Obninsk (∆ 15.9º), Malin Array (∆ 16º), Arti (∆ 17º).

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 04-49-35.8 40.98 47.6  15  57  5.2/115.6/166.5-7 98 IPC GS RAS (Accurate)
2 04-49-36.5 40.9 47.58  10  22   5.9/127.5-8 IPC GS RAS (Preliminary)
3 04-49-38.7 40.97 47.43  15  47   5.4  85 CSEM
4 04-49-38.8 40.934 47.514  13.8  94   5.4/280 28 NEIC
5 04-49-33.8 41.11 47.64  10  18  ML 5.7    IGUT
6 04-49-36.7 40.97 47.43  15  34  ML 5.9   72 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
  • IGUT - Institute of Geophysics, University of Tehran
  • RSSC - Republican Seismic Survey Center of Azerbaijan National Academy of Sciences
    • Epicenter
         Fig. 3 presents with red star the epicenter of this earthquake, its origin was located on the territory of Azerbaijan, at a depth of 15 km, 15 km S-E of Oguz, 33 km E-N-E of Ordzhonikidze, 198 km W-N-W of Baku, the capital city of Azerbaijan.

    Figure 3
    Macroseismic manifestations
         According to the Trend shocks with intensity up to seven MSK were felt on the territory of Sheki, where the epicenter of the quake was located. The shocks with an intensities up to 5-6 MSK were felt in Mingechevir, Yevlakh, Ganja, Goychay and other regions. There is no information about the destructions. Cracks on the walls of some houses were formed in Shaki after the earthquake, the rocks have fallen from the ancient fortress walls in some areas. This earthquake occurred in Azerbaijan was felt in two provinces of Turkey: Igdir and Erzurum. According to IA REGNUM this earthquake was felt in the Nagorno-Karabakh Republic with intensity 4 MSK, as well as in a number of settlements in Armenia: Aygedzor intensity 4-5 MSK, Ijevan, Noyemberyan intensity 4 MSK, Yerevan, Choratane intensity 3-4 MSK, Stepanavan, Kapan intensity 3 MSK, Vanadzor intensity 2-3 MSK. According to GS RAS the weak earthquake was felt in the border villages of Dagestan with intensity 2 MSK. Fig. 4, was obtained from USGS NEIC , it presents USGS Community Internet Intensity Map based on 7 responses in 6 cities.

    Figure 4
    Focal mechanism and seismic moment of the earthquake
         Focal mechanism Solution for this earthquake was obtained in IPC GS RAS with signs of initial arrivals of longitudinal waves at 42 stations, 28 of them registered compression waves (plus sign) and 14 registered tensile waves (minus sign). These stations are located in the interval of epicentral distances 0.5-81º and azimuth alignment Az = 10-358º. Focal mechanism in stereographic projection at the lower hemisphere is shown in fig. 5, elements of the mechanism are given in table 2. This earthquake has occurred under the action of S-W oriented (Az=210º) compression stresses, the tensile axis is directed N-W (Az = 301º) at an angle (Pl = 72º). Nodal planes strike in coincidence with the strike of the main Caucasus thrust (Physics of the Earth, 2013, № 4, Kadirov F.A. et al.). Nodal plane NP1 strikes S-E (STK=104º), NP2 strikes N-W (STK=318º). Both planes are inclined to the horizon at nearly the same angles (DP=47-48º). The type of motion along both planes - reverse faults with slip components, left lateral for NP1 and right lateral for NP2.
    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
    723020211 181211044866318 47114IPC GS RAS
  • IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences

    • Figure 5


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