Fig. 1 presents fragments of records obtained from digital stations Nonsavu (∆ 6.1º), Stephens Creek (∆ 40.7º), Kipapa (∆ 43.3º), Kappang (∆ 64.4º), Matsushiro (∆ 70.1º). Fig. 2 presents fragments of records obtained from digital stations Kamikawa-asahi (∆ 73.1º), Petropavlovsk (∆ 74.7º), Yuzhno-Sakhalinsk (∆ 75.2º), Pinyon Flats Observatory (∆ 76.6º), Vladivostok (∆ 78.1º).

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GS RAS registered two aftershocks with М>=4.8 within three hours after the main shock.

Fig. 1 was obtained from USGS NEIC, it presents USGS Community Internet Intensity Map made by 16 responses.

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Click here to view detailed macroseismic data (DyfitWeb service)

Focal mechanism solution of the origin was calculated at the GS RAS with signs of initial arrivals of P waves at 60 stations, including 12 stations which registered compression waves (plus signs), and 48 stations which registered tensile waves (minus signs). The stations are located in the interval of epicentral distances 6-103º and in azimuth sector Az=1-353º. 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 was caused by predominantly E-SE oriented tensile stresses (AZ=120-124º). One nodal plane NP1 strikes W-SW (STK=242-259º), another plane NP2 – strikes E-NE (STK=23-26º). NP1 plane is more horizontal (DP=8-15º) if compared with NP2 (DP=81-84º). The type of motion along NP1 – gentle normal fault with left-lateral strike-slip, along NP2 – normal fault. The seismic moment of the earthquake was obtained at the GS RAS from the spectra of longitudinal waves registered at the station "Yuzhno-Sakhalinsk" (∆=75.2º), it makes Mo=2.049*10**20 N*m, Mw=7.5. Seismic moment according to USGS NEIC data makes Mo=2.453*10**20 N*m, Mww=7.53. According to LDEO GCMT it makes Mo=2.52*10**20 N*m, Mw=7.5.