Information message about sensitive earthquake in the region of Kuril Islands, December 8, 2013 |
The sensitive earthquake with M=6.1 has occurred on December 8, 2013 at 17:24 GMT (21:24 Moscow time) in the region of Kuril Islands. |
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 16 min after
registration to the Ministry of Emergency of the Russian Federation (EMERCOM). |
Preliminary processing has been done with data from 31 stations, accurate processing - with data 52 stations. |
Fig. 1 presents fragments of records obtained from digital stations Kurilsk (∆ 1.2º), Yuzhno-Kurilsk (∆ 2.4º), Yuzhno-Sakhalinsk (∆ 5.1º), Severo-Kurilsk (∆ 7.7º), Vladivostok (∆ 12.6º). Fig. 1 presents fragments of records obtained from digital Tiksi (∆ 28.9º), Talaya (∆ 30.8º), Arti (∆ 54.8º), Obninsk (∆ 65.5º), Kislovodsk (∆ 70.3º).
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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 |
17-24-52.7 |
44.54 |
149.18 |
33 |
52 |
6.1/13 | 6/21 | 6.5-7 | | IPC GS RAS (Accurate) | 2 |
17-25-02.6 |
44.85 |
149.03 |
100 |
31 |
| 6/20 | 4-4.5 | | IPC GS RAS (Preliminary) | 3 |
17-24-54.4 |
44.54 |
149.11 |
30 |
185 |
| 5.9 | | 37 | CSEM | 4 |
17-24-53.9 |
44.51 |
149.072 |
25.5 |
119 |
| 5.9 | | 38 | NEIC | |
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 Pacific Ocean off the eastern coast of Kuril Islands, at the depth of 33 km, 130 km S-E of Kirilsk, 202 km E-N-E of Malokurilskoe and 271 km E-N-E of Yuzhno-Kurilsk. |
 Figure 3 |
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Aftershock |
Increased swismic activity in the area of Kuril Island has begun since December 5, 2013, where GS RAS registered 10 earthquakes М≥3.8, including 5 foreshocks М≥3.8. Within 6 hours after the main shock GS RAS registered 12 aftershocks М≥3.7, which are presented below. Two aftershocks according to GS RAS were felt in Kurilsk: on December 8 at 17:27 М=5.4 and intensity 2-3 MSK and at 17:40 М=5.2 and intensity 2 MSK. |
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 |
20134241 | 2013-12-08 17:27:30.0 | 44.63 | 149.2 | 33 | 4 | - | 5.4/ 1 | 4.5 | Kuril Islands | 20134243 | 2013-12-08 17:40:07.0 | 44.45 | 149.17 | 33 | 36 | - | 5.2/ 8 | 4-4.5 | Kuril Islands | 20134244 | 2013-12-08 19:20:25.0 | 44.5 | 149.23 | 33 | 10 | - | 3.9/ 5 | - | Kuril Islands | 20134247 | 2013-12-08 20:40:02.0 | 44.59 | 149.53 | 110 | 13 | - | 3.8/ 4 | - | Kuril Islands | 20134248 | 2013-12-08 21:56:10.0 | 44.49 | 149.31 | 33 | 26 | - | 4.5/ 9 | 2-2.5 | Kuril Islands | 20134249 | 2013-12-08 22:40:16.0 | 44.46 | 149.32 | 33 | 13 | - | 3.9/ 5 | - | Kuril Islands | 20134250 | 2013-12-08 23:13:28.0 | 44.53 | 149.31 | 33 | 13 | - | 3.8/ 7 | - | Kuril Islands | 20134251 | 2013-12-08 23:40:50.0 | 44.51 | 149.29 | 33 | 6 | - | 3.7/ 2 | - | Kuril Islands | 20134252 | 2013-12-09 00:05:29.0 | 44.47 | 149.36 | 33 | 9 | - | 3.9/ 3 | - | Kuril Islands | 20134257 | 2013-12-09 00:47:22.0 | 44.65 | 149.38 | 33 | 16 | - | 3.9/ 8 | - | Kuril Islands | 20134255 | 2013-12-09 00:55:32.0 | 44.55 | 149.23 | 33 | 11 | - | 4.0/ 5 | - | Kuril Islands | 20134256 | 2013-12-09 02:57:40.0 | 44.53 | 149.16 | 33 | 8 | - | 3.7/ 5 | - | Kuril Islands | |
Macroseismic manifestations |
In accordance with GS RAS this earthquake was felt in Kurilsk with intensity 4-5, in Reidovo with intensity 3, in Yuzhno-Kurilsk and Goriachy Pliazh with intensity 2 MSK.
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Historical records |
Epicenter of this earthquake was located 34 km E-N-E of epicenter from strong earthquake on June 18, 2010 М=6.2 |
Focal mechanism and seismic moment of the earthquake |
Focal mechanism solution was obtained in the IPC GS RAS with signs of initial arrivals of P waves at 49 stations, including 34 stations which registered the waves of compression (plus signs), and 15 stations which registered the waves of expansion (minus signs). The stations are located in the interval of epicetral distances of 5º –85º, not evenly by azymuth, mainly the stations are located in 1-st, 2-nd и 3-d azimuth quadrants.
Focal mechanism solution in stereographic projection at the lower hemesphere is presented at fig.4, elements of the mechanism are presented in table.2. Fig. 5, 6 present focal mechanism solutions obtained in USGS NEIC and in Quick CMT Catalog, USA, with CMT technique. All solutions are close.
This earthquake has occurred under insignificantly prevailing compression stress oriented south-east. Extension stress was oriented north-north-east.
Nodal plane NP1 in all solutions is nearly vertical (DP=76-83º) and strikes nearly along the latitude (STK=74-89º). Another plane NP2 is dipping under the angles DP=27-44º and strikes nearly along meridian (STK=178-194º). Type of motion is a reverse dip-slip with left-lateral components for the steeply dipping plane and a left-lateral strike-slip for the flatter plane.
According to USGS NEIC Mo=1.66*10**18 N*m, Mw=6.1, according to Quick CMT – Mo=1.65*10**18 N*m, Mw=6.1. |
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 |
43 | 40 | 19 | 149 |
41 | 256 | 89 | 76 | 132 | 194 |
44 | 21 | IPC GS RAS | 46 | 11 | 33 | 143 |
26 | 251 | 75 | 83 | 116 | 178 |
27 | 16 | NEIC | 46 | 11 | 33 | 143 |
26 | 251 | 75 | 83 | 116 | 178 |
27 | 16 | 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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