【摘要】 2009年7月9日在云南省姚安县发生M_S6.0地震,利用云南区域数字地震台网记录的M_L≥2.0余震波形记录,通过对S波观测记录谱进行传播路径、场地响应和仪器响应等影响的逐一消除,得到131个地震的震源谱。进而根据Brune圆盘震源模型,利用遗传算法计算地震矩、应力降、震源半径等震源参数。结果表明,该地震序列的M_O在10¹²—10¹⁶N·m,与近震震级有很好的线性关系,与震源半径呈线性关系;应力降与近震震级有一定线性趋势相关性;拐角频率和地震矩M_O之间有明显的依赖关系。更多还原

【Abstract】 Yao’an M_S 6.0 earthquake on July 9,2009 occurred in Yunnan.Using waveforms of the M_L≥2.0 earthquakes recorded by Yunnan Regional Digital Network,by removing propagation,site and instrument effects from the displacement spectra of the S_wave recordings,we obtain the source parameters of 131 M_L≥2.0 earthquakes based on the Brune disc model and Genetic algorithm,namely,the seismic moment M₀,stress drop △σ and rupture radius r,The results show that there is a good linear relation between M₀(10¹²-10¹⁶ N?m) and local magnitude M_L;M₀ and rupture radius r.△σ seems dependent on M_L;f_c increases with M₀decreasing according to the lg/_cM0 relation.更多还原