The 2023 Jishishan Ms6.2 Earthquake in Gansu Province,China:A Shallow Strong Earthquake with Thrust-dominated Components
The focal mechanism solution of the Jishishan Ms6.2 Earthquake on 18 Decem-ber 2023 in Gansu Province was made an inversion by the waveform fitting method in three-dimensional space using the observed waveform from the Regional Seismic Networks in China.The results show that the moment magnitude is Mw6.02,the strike/dip/slip of the first nodal plane are 305°/56°/61° and those of the second nodal plane are 169°/43°/125°.The best fine spatial position of the waveform fitting is 102.377°E,35.968°N,with depth of 9 km.The results show that main rupture extends along NW direction.It is in-ferred preliminary that the nodal plane Ⅱ is Fault-Plane,and seismogenic fault is the northern margin fault of the Lajishan mountains(eastern margin fault of the Jishishan mountain).Additionally,the event is a shallow strong earthquake induced by thrust-dom-inated faulting mechanism with little strike-slip component.
The 2023 Jishishan Ms6.2 earthquakeFocal mechanismCentroid depthThrust faultNorthern margin fault of the Lajishan