Informational message about the destructive earthquake in Iran-Iraq border region, August 18, 2014 |
| The destructive earthquake with M=6.2 has occurred on August 18, 2014 at 2:32 GMT (6:32 Moscow time) in Iran-Iraq 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 10 min after
registration to the Ministry of Emergency of the Russian Federation (EMERCOM). |
| Preliminary processing has been done with data from 50 stations, accurate processing - with data 62 stations. |
| Fig. 1 presents fragments of records obtained from digital stations Akhty (∆ 8.8º), Derbent (∆ 9.3º), Khabaz (∆ 11.7º), Kislovodsk (∆ 11.9º), Keshkin (∆ 13.4º). Fig. 2 presents fragments of records obtained from digital stations Ala-Archa (∆ 23.3º), Obninsk (∆ 23.8º), Arti (∆ 24.9º), Kirov (∆ 25.9º), Borovoe (∆ 26.0º). |
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 |
02-32-03.7 |
32.68 |
47.72 |
10 |
62 |
6.2/34 | 6.3/28 | 8.5-9 | 87 | IPC GS RAS (Accurate) | | 2 |
02-32-03.5 |
32.72 |
47.72 |
10 |
50 |
6.2/25 | 6.3/26 | 8.5-9 | 87 | IPC GS RAS (Preliminary) | | 3 |
02-32-05.5 |
32.58 |
47.62 |
10 |
708 |
Mw 6.2 | | | 40 | CSEM | | 4 |
02-32-05.26 |
32.74 |
47.67 |
10 |
105 |
Mw 6.2 | | | 40 | NEIC | | 5 |
02-32-05.9 |
32.703 |
47.695 |
10 |
29 |
ML 6.1 | | | | IGUT | |
| 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 |
| Epicenter |
| Fig.3 presents with red star epicenter of this earthquake which origin was located in the province of Ilam, Iran, at a depth of 10 km, 44 km S of Abdanana, 310 km E-N-E of Baghdad. |
Figure 3 |
|
| Aftershock |
| Geophysical Survey registered two foreshocks M=5 for 15 and 12 hours before and 10 aftershocks M>=4.5 within 9 hours 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 |
| 20142986 | 2014-08-17 11:24:15.0 | 32.63 | 47.82 | 10 | 17 | - | 5.0/ 9 | 5-5.5 | Iran-Iraq border region | | 20142987 | 2014-08-17 14:47:18.0 | 32.63 | 47.74 | 10 | 23 | - | 5.0/ 9 | 5-5.5 | Iran-Iraq border region | | 20142993 | 2014-08-18 03:11:29.0 | 32.65 | 47.68 | 10 | 20 | - | 4.7/ 12 | 4.5-5 | Iran-Iraq border region | | 20142994 | 2014-08-18 04:20:40.0 | 32.85 | 47.48 | 10 | 24 | - | 5.1/ 15 | 5.5-6 | Iran-Iraq border region | | 20142995 | 2014-08-18 04:39:30.0 | 32.79 | 47.7 | 10 | 20 | - | 4.8/ 13 | 4.5-5 | Iran-Iraq border region | | 20142996 | 2014-08-18 05:25:49.0 | 32.63 | 47.73 | 10 | 42 | - | 5.9/ 19 | 7.5-8 | Iran-Iraq border region | | 20142998 | 2014-08-18 06:34:46.0 | 32.79 | 47.71 | 10 | 16 | - | 4.3/ 8 | 3.5-4 | Iran-Iraq border region | | 20142999 | 2014-08-18 06:58:57.0 | 32.66 | 47.65 | 10 | 21 | - | 4.5/ 7 | 4-4.5 | Iran-Iraq border region | | 20143000 | 2014-08-18 08:05:24.0 | 32.6 | 47.53 | 10 | 38 | - | 5.0/ 20 | 5-5.5 | Iran-Iraq border region | | 20143001 | 2014-08-18 11:06:51.0 | 32.59 | 47.64 | 10 | 26 | - | 4.8/ 10 | 4.5-5 | Iran-Iraq border region | | 20143002 | 2014-08-18 11:23:01.0 | 32.7 | 47.64 | 10 | 45 | - | 5.4/ 23 | 6-6.5 | Iran-Iraq border region | | 20143003 | 2014-08-18 11:51:32.0 | 32.67 | 47.6 | 10 | 62 | - | 5.9/ 35 | 7.5-8 | Iran-Iraq border region | |
| Macroseismic manifestations |
| According to ITAR-TASS information was received about 250 residents of the area Murmur injured and wounded as a result of undeground shocks. The Governor of one of the affected provinces Majid Asgari told the news agency IRNA that the agricultural areas of Abadan were severely damaged. According to IRNA 8 of 11 villages located close to the town Abdanan in Ilam Province were destroyed.
Figure 4 was obtained from USGS NEIC , it presents USGS Community Internet Intensity Map, based on 8 responses in 6 cities. |
Figure 4 |
|
| Historical records |
| Territory of Iran is on several major crustal faults, it is a main cause of frequent earthquakes. One of the most destructive earthquakes M=6.8 has occurred on December 26, 2003, it affected historical monument - the city of Bam in Kerman Province. Then it was killed nearly 31,000 people - a quarter of the this city population. An earthquake M=7.7 in June 1990 in the northwestern provinces of Gilan and Zanjan was the worst such disaster in Iran: 37,000 persons were killed, 100,000 injured, 27 towns and 1800 villages were totally destroyed.
|
| Focal mechanism and seismic moment of the earthquake |
| Focal mechanism in stereographic projection is shown in Fig. 5.6, it was obtained in the USGS NEIC based on W-phase Moment Tensor (Mww) technique and in the Quick CMT Center with CMT technique. Elements of the mechanism are presented in Table 2. Both solutions obtained in these different centers are close.
The earthquake has occurred under predominate action of compressing stress oriented south-west. One of the nodal planes NP1 in all solutions is almost vertical (DP=68-72º), another – NP2 is nearly horizontal (DP=19-27º). NP1 strikes South-East (STK=109-119º), NP2 strikes North-West (STK=310-327º). The type of motion along the vertical plane - reverse faults with minor left-latteral slip components, for horizontal plane – overthrusts with right-latteral slip components.
According to the USGS NEIC - Mo=2.92*10**18 Nm, Mw=6.2, according to the Quick CMT - Mo=2.65*10**18 Nm, Mw=6.2. |
| 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 |
| 63 | 24 | 26 | 212 |
3 | 120 | 119 | 72 | 87 | 310 |
19 | 100 | NEIC | | 63 | 352 | 21 | 211 |
15 | 115 | 109 | 68 | 74 | 327 |
27 | 125 | Quick CMT | |
| NEIC - National Earthquakes Information Center of US Geological Service |
| Quick CMT - Quick CMT catalog |
Figure 5 | 
Figure 6 |
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