【摘要】 四川数字强震台网中的9个台站获取了2011年4月10日四川炉霍Ms5.3级地震完整的三分向加速度记录,高频成分丰富,频谱主要成分集中在0.1～0.3s之间,最大加速度值为炉霍台EW向405.8cm/s2。震后的地震宏观考察结果表明,本次地震的极震区地震烈度达Ⅶ度,等震线沿鲜水河断裂呈NW-SE向的不规则椭圆形,NW部的面积明显大于SE部。综合分析认为,震区建筑物自振周期与本次地震加速度反应谱的高频成分高度吻合是震害偏重的主要原因,"崩科"藏式建筑抗震性能较差亦加重了震害。联系到本次地震P波向NW方向传播速度明显快于SE方向、等震线形态以及余震稀少等事实,推测这次地震系2010年4月14日青海玉树Ms7.1级地震的远程触发,导致鲜水河断裂上应力调整而产生弹性回跳的结果。更多还原

【Abstract】 In the Luhuo Ms 5.3 earthquake three components of the earthquake acceleration were recorded by the nine strong-motion stations of the Sichuan digital seismic network.The high frequency parts of the seismic wave are plentiful and the main components of its spectrum is between 0.1-0.3 s.The maximum EW-orientated value of the acceleration recorded by the Luhuo station is 405.8 cm/s2.According to the survey of the earthquake damages,the intensity of the meizoseismal area is Ⅶ degree.The isoseismic line is shaped as an anomalous ellipse and the orientation of its long axis is NW-SE orientation along the Xianshuihe fault.The area of the NW part of the intensity area is obviously larger than that of the SE part.The natural vibration period of the buildings is consistent with the high frequency components of the seismic acceleration.Thus,this made the damages more seriously.The poor antiseismic performance of "Bengke"(the style of the Tibetan building) is another causation for the serious destroy.The NW-orientated propagation velocity of the P wave is faster than the SE-orientated one and the aftershock is so exiguous.All the above suggests that the Ms 7.1 earthquake occurred in Yushu County of Qinghai Province on April 14,2010 led to the stress adjustment and the elastic rebound on the Xianshuihe fault,so as to trigger the Luhuo Ms 5.3 earthquake.更多还原