【摘要】 通过重构用于确定视震源时间函数有效持续时间的判别函数,对提取视震源时间函数的 PLD 方法进行了改进;利用合成资料和实际资料,验证了改进后 PLD 方法的可行性和稳定性.将 PLD 方法应用于2005年克什米尔 M_w 7.6地震及具11个余震的1887条记录,在84个台站处获得了这次地震的视震源时间函数.分别平均从不同台站的 P 波、S 波、Rayleigh 波和 Love 波中得到的视震源时间函数,获取了主震的平均视震源时间函数.对视震源时间函数的分析表明,2005年克什米尔 M_w 7.6地震的持续时间大约为25 s,这是一次"急始型"地震,总体上表现为圆盘形破裂.但有迹象表明,破裂在初期有向西北方向发展的单侧传播趋势.更多还原

【Abstract】 The PLD method for retrieval of apparent source time function (ASTF) is improved by reconstructing the criteria function to be used for determination of the effective duration time of the ASTF.Using the synthetic and observed data,the feasibility and stability of the improved PLD method are verified.By applying the PLD method to 1887 waveform recordings of the 2005 Kashmir M_w 7.6 earthquake and its 11 aftershocks,the ASTFs of the main shock are obtained at 84 stations.By averaging the ASTFs from the P waves,S waves,Rayleigh waves and Love waves from different stations,the average ASTFs of the main shock are constructed.The analysis of the ASTFs indicates that the duration time of the 2005 Kashmir M_w 7.6 earthquake is about 25 s,and it is a quickly-starting earthquake.In general feature,the STF appears to be like a STF of a circular source model,however,some details of the ASTFs suggest that the rupture at the beginning was unilateral extending toward NW direction.更多还原