The red marker on the map shows the epicenter of the earthquake, the origin of which was in Dagestan at a depth of 10 km, 3 km SW of Shaitli, 7 km E-NE of Kidero, 11 km NW of Bezhta and 146 km W-SW of Makhachkala.
|
Time in origin (GMT) |
Latitude, degree |
Longitude, degree |
Depth, km |
Stations number |
Ms/N |
mb/N |
I0 (calculated) |
GAP |
Center |
1
|
03:34:49.0
|
42.22 |
46.04 |
10.0 |
48
|
|
4.8/22 |
4.5-5 |
|
GS RAS(Verified) Federal research center, Geophysical survey of Russian Academy of Sciences
|
2
|
03:34:53.3
|
42.85 |
46.16 |
10.0 |
11
|
|
5.0/10 |
5-5.5 |
|
GS RAS(Preliminary) Federal research center, Geophysical survey of Russian Academy of Sciences
|
3
|
03:34:49.0
|
42.36 |
46.09 |
2.0 |
154
|
|
4.8 |
|
45
|
CSEM European - Mediterranean seismological center
|
4
|
03:34:50.3
|
42.3 |
46.0 |
10.0 |
59
|
|
4.8 |
|
45
|
NEIC National Earthquakes Information Center of US Geological Service
|
5
|
03:34:49.3
|
42.14 |
45.99 |
2.0 |
6
|
К 12 |
|
|
|
NOGSR North Osetia (Alania) Regional Seismological Centre, Geophysical Survey, Russian Academy of Sciences
|
6
|
03:34:50.0
|
42.15 |
46.02 |
2.0 |
4
|
К 12.7 |
|
|
|
DAGSR North-East Regional Seismological Centre, Magadan, Geophysical Survey, Russian Academy of Sciences
|
Fig. 1 presents fragments of records obtained from digital stations Botlikh (∆ 0.5º), Groznyy (∆ 1º), Garni (∆ 2.4º), Neytrino (∆ 2.7º). Fig. 2 presents fragments of records obtained from digital stations Khabaz (∆ 2.8º), Shidzhatmaz (∆ 2.9º), Kislovodsk (∆ 3º), Krasnaya Polyana (∆ 4.5º).
Image 1
Image 2
GS RAS registered one aftershock with М=3.6 in 5 hours 16 minutes after the main shock.
N |
Time in origin (GMT) |
Latitude, degree |
Longitude, degree |
Depth, km |
Stations number |
Ms/N |
mb/N |
I0 (calculated) |
Region |
20213615
|
03/09/2021 08:50:35.0.0 |
42.19 |
46.03 |
10.0 |
16 |
|
3.6/5 |
2-2.5 |
Eastern Caucasus
|
According to Dagestan Branch of GS RAS the earthquake was felt in Kidero, Bezhta with intensity of 4-5 MSK, in Tlyarat with intensity of 4 MSK, in Khunzakh with intensity of 3 MSK, in Khasavyurt, Makhachkala, Botlikha with intensity of 2-3 MSK.
The focal mechanism solution of the origin of the earthquake was calculated by GS RAS with signs of initial arrivals of P waves at 23 stations, including 8 stations which registered compression waves (plus signs) and 15 stations which registered tensile waves (minus signs). These stations are located in the epicentral distances of 1-44.7º and in azymuth sector Az=5-350º. The focal mechanism solution in stereographic projection on the lower hemisphere and the elements of the mechanism are presented in the table. The earthquake occurred under the action of a slight prevalence of compressive stresses oriented to the southeast (AZ=143º). One nodal plane NP1 strikes west (STK=278º), another plane NP2 strikes N-NE (STK=19º). NP1 plane is more flattened horizontally (DP=50º) if compared with NP2 (DP=77º). The type of motion along NP1 – right latteral slip, along NP2 – left latteral slip with reverse fault component.
Axes of main strengths |
Nodal planes |
Center |
|
T |
P |
N |
NP1 |
NP2 |
PI: 38
Azm: 247
|
PI: 17
Azm: 143
|
PI: 47
Azm: 34
|
Stk: 278
Dp: 50
Slip: 163
|
Stk: 19
Dp: 77
Slip: 41
|
GS RAS Federal research center, Geophysical survey of Russian Academy of Sciences
|
|