Focal Mechanism of M_L≥3.5 Earthquake in Northeast Yunnan from 2008 to 2012

Based on data recorded by the Yunnan Digital Seismic Network, we calculate and analyzes the focal mechanism of M_L≥3.5 earthquakes in northeastern Yunnan from 2008 to 2012 using the method of full waveform simulation. The result shows:(1) the strike of earthquake rupture surfaces show diversity distribution, but most of the nodal plane has high dip angle, the focal mechanisms are mainly of strike-slip type. (2) The principal compressive stress axis is in the NNW-SSE direction, the principal extension axis is in the NEE-SWW direction, the secondary stress axis is to the vertical. (3) Most of the seismic source parameters are basically the same except that of some small earthquakes.