Reference information about seismic conditions on the territory of Dagestan Republic for the period between January 1999 and December 2000 | | According to the data of Information Processing Center (IPC) in Obninsk and Dagestan Experimental Methodical Expedition of Geophysical Survey of RAS more than 1100 earthquakes with magnitude Ms more than 1.0-1.5 have happened in the region of Eastern Caucasus (territory of Dagestan Republic) for the period since January 1999 till December 2000. Nearly 40 of them have been felt in living places with intensities 2-3 and more MSK. First of all it is necessary to specify the origin zone of Dagestan earthquake, which happened on January 31, 2000 (43.11 N, 46.99 E) with magnitude Ms=5.6 and intensity in hypocenter 6-7 MSK. Most of the earthquakes have been detected in this zone (nearly 800). | | IPC GS RAS also has obtained information with parameters of this event from some seismological centers, these data are given in table 1: | | Note: Other seismic activities may be considered as background, without origin zones and constantly registered in the analyzed period of time.
| | 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 |
15-35-20.4 |
42 |
47 |
15 |
9 |
4.5/3 | | 5.5-6 | | IPC GS RAS (Preliminary) | | 2 |
15-35-18.30 |
42 |
47 |
15 |
15 |
4.60/3 | | 6.5 | | IPC GS RAS (Improved) | | 3 |
15-35-19.3 |
42 |
47 |
|
13 |
| 4.3 | | | NEIC | | 4 |
15-35-18.7 |
42 |
47 |
|
6 |
| | | | DRIPC (Preliminary) | | 5 |
15-35-18.7 |
42 |
47 |
9 |
7 |
| | | | DRIPC (Improved) | | | IPC GS RAS - Informational Processing Center, Geophysical Survey, Russian Academy of Sciences | | NEIC - National Earthquakes Information Center of US Geological Service | | DRIPC - Regional Informational Processing Center of Dagestan Experimental-Methodical Seismological Department Geophysical Survey Russian Academy of Sciences | | Aftershock | | For nearly two years the long lasting aftershock process accompanies escape of seismic energy in the origin zone of Dagestan earthquake on January 31, 1999. Aftershocks of different classes are registered here even now.
Absolutely different character of seismic energy emission is in the origin place of central part of Dagestan. It is possible to say about the series of earthquakes, which have happened here in the two-year period. Thus, it was noticed that in the year 2000 each strong earthquake here (in July, September and December) with K=10-12 was accompanied by two much weaker aftershocks having K=8-9.
| | Macroseismic manifestations | | The strong earthquake has happened in Dagestan on December 2, 2000 at 18:35 Moscow time (15:35 GMT), it covered central mountain part of the republic. From data of Dagestan EMSP this earthquake was felt on the territory of Dagestan Republic with intensity up to 6.5 MSK. The most reliable data about intensity of this event are:
Muti (Akushinsk rgn.), Chuni (Levshinsk rgn.), Akusha -5-6 MSK;
Kuhum, Levashi – 4-5 MSK;
Sergokala – 4 MSK;
Urkarah, Karaburgthent – 3 MSK;
Gunib, Manas, Mahachkala, Buinaksk – 2-3 MSK.
From information of Extraordinary Events Ministry there were no victims among the population, however some houses and buildings were damaged.
Manager of seismic station "Mahachkala" has reported that this earthquake destroyed television retransmit station in Akusha settlement, where all equipment was damaged after falling down on the floor. TV tower has leaned much and almost fallen down. Buildings of local authorities and police station have been seriously damaged. Landslide has happened and big stones damaged many living houses located near the mountain. The walls of houses located in the upper part of this settlement are in cracks and have numerous damages of their plaster cover, some of these houses of type A and B have serious damages of class 2.
From ITAR TASS information the buildings of hospital and military registration center received a serious damage in regional center Levashi. Manager of seismic station "Mahachkala" has reported about serious damage to TV transmitting tower in Levashi. Small settlements located closer to the hypocenter have damages of first and second class for buildings of type A and B.
Special commission works today in the regions of natural disaster, it should estimate the level of damage on site.
| | Historical records | | According to the data of Information Processing Center (IPC) in Obninsk and Dagestan Experimental Methodical Expedition of Geophysical Survey of RAS more than 1100 earthquakes with magnitude Ms more than 1.0-1.5 have happened in the region of Eastern Caucasus (territory of Dagestan Republic) for the period since January 1999 till December 2000. Nearly 40 of them have been felt in living places with intensities 2-3 and more MSK. First of all it is necessary to specify the origin zone of Dagestan earthquake, which happened on January 31, 2000 (43.11 N, 46.99 E) with magnitude Ms=5.6 and intensity in hypocenter 6-7 MSK. Most of the earthquakes have been detected in this zone (nearly 800). Aftershock activities go on here till now. The last registered earthquake has happened in this zone on September 22, 2000 at 02:27 with K=10 and location 42.98 N, 46.98 E H=30km. The weaker shocks (K=7-9) were registered in this area by Dagestan regional network till November 19.
It is necessary to pay attention to seismic activity in the other region of Dagestan, namely to a central mountain part (42.15-42.30 N , 47.1-47.5 E). Such activity was observed here on January 26, 1999 with K=11.8 and repeated in year 2000 (see table1):
| | Table 1 |
| Date | Time | North latitude,
(degr.) | East. longtitude,
(degr.) | Depth,
km | Energy
class | | 05.07.00 | 17-29-26.98 | 42.158 | 47.402 | 11. | 10.6 | | 05.07.00 | 18-06-07.70 | 41.990 | 47.441 | 18. | 8.0 | | 06.07.00 | 16-49-54.50 | 42.016 | 47.413 | 08. | 9.0 | | 24.09.00 | 06-34-32.42 | 42.158 | 47.402 | 21. | 10.3 | | 24.09.00 | 06-39-43.56 | 42.260 | 47.147 | 05. | 9.5 | | 24.09.00 | 07-35 22.75 | 42.185 | 47.146 | 01. | 9.2 |
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The earthquake on September 24 at 06:34 had the strongest macro seismic effect and was felt in the following settlements of Dagestan: Levashi, Uncukul - 4-5 MSK, Urkarah -3.5-4 MSK, Buinaksk, Gergebil, Gunib –3 MSK, Akusha, Mahachkala, Sudahar –2-3 MSK.
The other strong earthquake has happened in this region on December 2, 2000 at 15:35 with magnitude 4.6 and destructive consequences. Parameter of the origin determined by different centers are presented in table 2. Locations of hypocenters for the earthquakes, which happened here in 2000 are shown on figure 1 according to the data of Dagestan regional network.
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Figure 1 |
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