Information message about destructive earthquake at the southern coast of Iran on September 10, 2008 |
The earthquake with М=5.9 has occured on September 10, 2008 at 11:00 GMT (15:00 Moscow time) at the southern coast of Iran and it caused victims and destructions. |
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 40 min after
registration to the Ministry of Emergency of the Russian Federation (EMERCOM). |
Preliminary processing has been done with data from 33 stations, accurate processing - with data 42 stations. |
Fig. 1 presents fragments of records obtained from digital stations Garni (∆ 16º), Kislovodsk (∆ 20º), Borovoe (∆ 28.2º), Kurchatov (∆ 29.3º), Arti (∆ 29.5º). Fig. 2 presents fragments of records obtained from digital stations Obninsk (∆ 31.4º), Vasula (∆ 37.4º), Lovozero (∆ 42.9º), Talaya (∆ 43.4º), Hailar (∆ 53.2º). |
 Figure 1 |  Figure 2 |
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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 |
11-00-34.3 |
27.01 |
55.86 |
15 |
42 |
5.9/22 | 6.1/33 | 7.5-8 | 147 | IPC GS RAS (Accurate) | 2 |
11-00-38.0 |
26.91 |
55.88 |
50 |
33 |
5.9/18 | 6.1/22 | | 147 | IPC GS RAS (Preliminary) | 3 |
11-00-37.9 |
26.95 |
55.78 |
30 |
353 |
6.1Mw | | | 50 | CSEM | 4 |
11-00-34.8 |
26.83 |
55.83 |
15 |
176 |
6.1Mw | 6.1/124 | | 18 | NEIC (Accurate) | 5 |
11-00-40.9 |
27.01 |
55.78 |
56 |
73 |
6.1Mw | 6.1/59 | | | NEIC (Preliminary) | 6 |
11-00-38.7 |
26.94 |
55.71 |
6.6 |
15 |
5.8ML | | | 2688 | IIEES (Accurate) | 7 |
11-00-38.7 |
27.15 |
55.81 |
14 |
7 |
5.7ML | | | 26 | IIEES (Preliminary) | |
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 |
IIEES - International Institute of Earthquake Engineering and Seismology, Tehran, Iran |
Epicenter |
Fig.3 was shared from International Institute of the Earthquakes and Engineering Seismology, Tehran, and it shows epicenter of the earthquake, which was located in Persian Gulf near the south coast of Iran, at 55 km W of Qeshm, at 62 km SW of Bandar-Abbas. |
 Figure 3 |
|
Aftershock |
Within the fist full day after the main shock Geophysical Survey of RAS registered 3 aftershocks with magnitudes from 4.9 to 5.3. |
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 |
20083016 | 2008-09-10 11:33:11.0 | 26.95 | 56.03 | 15 | 18 | - | 4.9/ 12 | 4.5-5 | Southern Iran | 20083029 | 2008-09-11 01:11:36.0 | 26.54 | 56.05 | 15 | 8 | - | 5.3/ 4 | 5.5 | Southern Iran | 20083028 | 2008-09-11 02:16:09.0 | 27.03 | 55.94 | 15 | 25 | - | 5.3/ 14 | 5.5 | Southern Iran | |
Macroseismic manifestations |
The powerful earthquake which happened in the south of Iran has killed 7 persons and injured 50 persons. One of the biggest oil processing plants located in Bandar-Abbas was not influences with the earthquake, however nearly hundred of living buildings were destroyed in Khormozgan Province. The earthquakes was also felt in the United Arab Emirates, Katar and Oman. Fig.4 was shared from the sight of NEIC USA and presents the map with instrumental intensities. |
 Figure 4 |
|
Historical records |
Iran is located in the zone of increased seismic activity. In the last century as a result of 20 most significant shocks nearly 170 thousand people were killed (ITAR TASS). In December 2003 the underground shock with magnitude 6,8 almost fully destroyed ancient town Bam. |
Focal mechanism and seismic moment of the earthquake |
Focal mechanism solutions of the earthquake’s origin 10.09.2008 were calculated with TMC method in NEIC USA, USGS USA and Harvard Center USA, HRVD (Global CMT Catalog) and they are presented in table 2 and shown on figures 5, 6. These solutions are almost the same.
The earthquake has occurred under the action of compression forces oriented to the south-east direction. Both nodal planes have north-eastern direction of propagation and are rather steep falling. The type of motion along both planes – uplift.
The value of seismic moment Мо obtained in IPC GS RAS from Р-wave spectra at three stations: Arti (∆ 29.5º), Obninsk (∆ 31.4º), Talaya (∆ 43.4º) makes Мо=1.8* 10** 18 n*m, the value of moment magnitude calculated from Kanamori formula makes Mw = 6.1.
The value of seismic moment Мо in accordance with NEIC makes 1.1* 10** 18 n*m, the value of moment magnitude Mw = 6.0; and in accordance with HRVD – Мо=1.52* 10** 18 n*m, Mw = 6.1.
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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 |
74 | 9 | 12 | 150 |
9 | 242 | 69 | 58 | 101 | 229 |
34 | 73 | NEIC | 84 | 341 | 6 | 149 |
1 | 240 | 61 | 51 | 92 | 238 |
39 | 88 | HARVARD | |
NEIC - National Earthquakes Information Center of US Geological Service |
HARVARD - Harvard Geophysical Center (USA) |
 Figure 5 |  Figure 6 |
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