Information message about the strong earthquake in Guatemala on November 07, 2012 |
| The strong earthquake with M=7.4 which caused victims and destructions has occurred in region Offshore Guatemala on November 07, 2012 at 16:35 GMT (20:35 Moscow time). |
| 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 20 min after
registration to the Ministry of Emergency of the Russian Federation (EMERCOM). |
| Preliminary processing has been done with data from 37 stations, accurate processing - with data 49 stations. |
| Fig. 1 presents fragments of records obtained from digital stations Bilibino (∆ 81.4º), Seimchan (∆ 88.8º), Petropavlovsk (∆ 90.2º), Tiksi (∆ 90.2º), Magadan (∆ 91.1º). Fig. 2 presents fragments of records obtained from digital stations Vasula (∆ 92.2º), Severo-Kurilsk (∆ 92.6º), Yakutsk (∆ 97.4º), Kiev (∆ 97.5º), Obninsk (∆ 98.5º).
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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 |
16-35-48.2 |
14.14 |
-91.84 |
33 |
37 |
7.4/16 | 6.5/24 | 8.5-9 | 63 | IPC GS RAS (Preliminary) | | 2 |
16-35-48.1 |
14.09 |
-91.79 |
33 |
49 |
7.4/28 | 6.5/29 | 8.5-9 | 63 | IPC GS RAS (Accurate) | | 3 |
16-35-48.0 |
14.05 |
-91.75 |
30 |
659 |
7.3 Mw | | | 28 | CSEM | | 4 |
16-35-50.3 |
14.08 |
-91.91 |
41.6 |
586 |
7.4 Mw | 6.6/512 | | | NEIC (Preliminary) | | 5 |
16-35-50.0 |
13.99 |
-91.97 |
24.1 |
635 |
7.4/538 | 6.6/588 | | 58 | NEIC (Accurate) | |
| 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 |
| Epicenter |
| Fig. 3 presents with red star epicenter of this earthquake which origin was located in region Offshore Guatemala, at the depth of 33 km, 50 km S-S-W of Retalhuleu, 97 km South of San-Marcos and 111 km W-S-W of Escuintla. |
Figure 3 |
|
| Aftershock |
| GS RAS registered 3 aftershocks with M≥5 within 10 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 |
| 20124137 | 2012-11-07 17:04:03.0 | 14.13 | -91.74 | 33 | 11 | - | 5.4/ 7 | 4.5 | Guatemala | | 20124140 | 2012-11-07 22:42:47.0 | 13.96 | -92 | 33 | 13 | - | 5.4/ 5 | 4.5 | Off coast of Chiapas, Mexico | | 20124143 | 2012-11-08 02:20:35.0 | 14.24 | -92 | 33 | 22 | - | 5.0/ 10 | 3.5-4 | Near coast of Chiapas, Mexico | |
| Macroseismic manifestations |
| In accordance with RIA-Novosti 48 persons were killed as a result of this earthquake. The Department of San-Marcos reported about 39 persons killed in the earthquake’s most affected region, and this number may increase after the proper estimation. The number of injured makes now 155 persons and nearly 100 persons are missing.
Dozens of houses were destroyed in settlements of San-Marcos department, including the buildings of local authorities and police. Road links were disrupted. Many towns were left without electricity and telephone.
Fig. 4 shared from USGS NEIC, presents the USGS Community Internet Intensity Map by 580 responses in 157 cities.
|
Figure 4 |
|
| Focal mechanism and seismic moment of the earthquake |
| Focal mechanism of the earthquake was obtained in GS RAS with signs of initial arrivals of P-waves at 227 stations (219 – plus signs, 8 – minus signs) and with CMT method in NEIC USGS and Quick CMT Catalog, USA. Focal mechanism solutions in stereographic projection at the lower hemisphere are presented at figures 5-7, elements of the mechanism are presented in table 2. All solutions obtained in various centers are identical.
The earthquake has occurred under the action of S-W oriented compression stress. NP1 nodal plane is steeply dipping (DP=61-72º), NP2 plane is more flat (DP=26-30º). Type of motion is reverse fault for NP1 and thrust for NP2.
Seismic moment of the earthquake in accordance with USGS NEIC makes Мо=1.3*10**20 N*m, Mw=7.4, in accordance with Quick CMT Мо=1.29*10**20 N*m, Mw=7.3. |
| 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 |
| 59 | 63 | 24 | 203 |
18 | 301 | 127 | 72 | 109 | 260 |
26 | 46 | IPC GS RAS | | 73 | 58 | 16 | 212 |
7 | 304 | 128 | 61 | 98 | 291 |
30 | 76 | NEIC | | 71 | 33 | 19 | 208 |
1 | 299 | 119 | 64 | 92 | 296 |
26 | 87 | Quick CMT | |
| IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences |
| NEIC - National Earthquakes Information Center of US Geological Service |
| Quick CMT - Quick CMT catalog |
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