Fig. 1 presents fragments of records obtained from digital stations Severo-Kurilsk (∆ 3.3º), Magadan (∆ 8.4º), Seimchan (∆ 10.8º), Yuzhno-Kurilsk (∆ 12.9º), Anadyr (∆ 14.8º). Fig. 2 presents fragments of records obtained from digital stations Tiksi (∆ 23.2º), Talaya (∆ 33.7º), Norilsk (∆ 36º), Arti (∆ 53.5º), Obninsk (∆ 62.6º).

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Image 2

GS RAS registered 15 aftershocks with magnitude M>=4.2 within two days after the main shock. The aftershock on August 17 at 22:27 was felt in Nikolaevka with a magnitude of 3, in Petropavlovsk-Kamchatsky, Pionersky, Novoye with a magnitude of 2-3 MSK. The aftershock on August 18 at 11:34 was felt in Petropavlovsk-Kamchatsky with a magnitude of 3 MSK. The aftershocks on August 19 at 06:16 and 07:24 were felt in Petropavlovsk-Kamchatsky with a magnitude of 2 MSK.

According to the data of the Kamchatka Branch of GS RAS, the earthquake was felt in Petropavlovsk-Kamchatsky, Rybachy, Vilyuchinsk with a magnitude of 5 MSK, in Elizovo with a magnitude of 4-5 MSK, in Pauzhetka with a magnitude of 4 MSK, in Milkovo, Kavalersky, Ust-Bolsheretsk, Severo-Kurilsk, Ust-Kamchatsk with a magnitude of 3 MSK, in Oktyabrsky, Klyuchi with a magnitude of 2-3 MSK, in Krutoberegovo with a magnitude of 2 MSK.

Click here to view detailed macroseismic data (DyfitWeb service)

Focal mechanism solution of the origin was calculated in GS RAS with signs of initial arrivals of P waves at 112 stations, including 87 stations which registered compression waves (plus signs), and 25 stations which registered tensile waves (minus signs). The stations are located in the epicentral interval of 1-86º and azimuth sector Az= Az=7-358º. Focal mechanism solution in stereographic projection on the lower hemisphere and elements of the mechanism are presented in the table. The table also contains focal mechanism solutions obtained at the USGS NEIC with WW-phase Moment Tensor (Mww) technique and in Lamont-Dohert Earth Observatory of Columbia University, USA (LDEO GCMT) with СМТ (Centroid moment tensor) technique. Solutions from different centers are close. The earthquake occurred under the prevailing action of compressional stresses oriented to the southeast (AZ=127-136º). One nodal plane NP1 strikes SW (STK=213-228º), another plane NP2 strikes NE (STK=37-45º). NP1 plane is more horizontal (DP=19-27º) if compared with NP2 (DP=63-71º). The type of motion along NP1 is thrust, along NP2 - reverse fault. The seismic moment of the earthquake was obtained in the GS RAS from the spectra of P waves registered at the station "Obninsk" (∆=62.6º), it makes Mo=3.035*10**19 N*m, Mw=7.0. Seismic moment according to USGS NEIC makes Mo=4.203*10**19 N*m, Mww=7.0. According to LDEO GCMT it makes Mo=4.24*10**19 N*m, Mw=7.0.