Fig. 1 presents fragments of records obtained from digital stations Chiang Mai Array Site 31 (∆ 22.7º), Tennant Creek (∆ 35.9º), Port Moresby (∆ 45.9º), Stephens Creek (∆ 46.8º), Taejon (∆ 47.2º) for the first earthquake. Fig. 2 presents fragments of records obtained from digital stations Chiang Mai Array Site 31 (∆ 22.5º), Tennant Creek (∆ 35.9º), Port Moresby (∆ 45.8º), Stephens Creek (∆ 46.8º), Taejon (∆ 47.1º) for the second earthquake.

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GS RAS registered one aftershock with М=4.7 in 3 hours 8 minutes after the second shock.

Fig. 1 was obtained from USGS NEIC, it presents USGS Community Internet Intensity Map made by 10 responses in 4 cities for the first earthquake.
Fig. 2 was obtained from USGS NEIC, it presents USGS Community Internet Intensity Map made by 5 responses in 5 cities for the second earthquake.

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Click here to view detailed macroseismic data (DyfitWeb service)

The focal mechanism solutions for the first earthquake in stereographic projection on the lower hemisphere and elements of the mechanism are presented in the table. The table contains focal mechanisms solutions obtained in USGS NEIC with W-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. An earthquake occurred under the action of slight prevalence of compression stresses oriented to the southwest (AZ=219-222º). One nodal plane NP1 strikes NW (STK=305-317º), another plane NP2 strikes SE (STK=126-132º). NP1 plane lies flatter (DP=9-18º) if compared with NP2 (DP=73-81º).The type of motion along NP1 – thrust, along NP2 – reverse fault. According to USGS NEIC – Mo=1.739*10**19 N*m, Mwb=6.8, according to LDEO GCMT – Mo=1.34*10**19 N*m, Mw=6.7. For the second earthquake the focal mechanism solution of the origin was calculated in GS RAS with signs of initial arrivals of P waves at 54 stations including 46 stations which registered compression waves (plus signs) and 8 stations which registered tensile waves (minus signs). Threse stations are located in the interval of epicentral distances 1.7-94.4º and in the azimuth sector Az=5-348º. The focal mechanism solution in the stereographic projection on the lower hemisphere and the elements of the mechanism are presented in the table. The table also presents focal mechanism solutions obtained in USGS NEIC with W-phase Moment Tensor (Mww) technique and at the Lamont-Dohert Earth Observatory of Columbia University, USA (LDEO GCMT) according to the CMT (Centroid moment tensor) technique. Solutions according to different centers are close. The earthquake occurred under the action of slight prevalence of compression stresses oriented to the southwest (AZ=220-240º). One nodal plane NP1 strikes N-NE (STK=27º) according to GS RAS and N-NW (STK=325-327º) according to USGS NEIC and LDEO GCMT, another plane NP2 strikes SE (STK=126-133º). NP1 lies flatter (DP=13-21º) if compared with NP2 (DP=70-84º). The type of motion along NP1 – right latteral slip according to GS RAS and thrust according to USGS NEIC and LDEO GCMT, along NP2 – reverse fault. According to USGS NEIC – Mo=2.477*10**19 N*m, Mww=6.9, according to LDEO GCMT – Mo=3.12*10**19 N*m, Mw=6.9.