1985年禄劝地震部分余震的精确定位  

ACCURATE HYPOCENTER DETERMINATION OF AFTERSHOCKS OF THE 1985 LUQUAN EARTHQUAKE

作　　者：吴明熙 王鸣[1] 孙次昌[1] 柯兆明 王培德[1] 陈运泰[1] 吴大铭[2] 

机构地区：[1]国家地震局地球物理研究所 [2]美国宾厄姆顿纽约州立大学地球科学系

出　　处：《地震学报》1990年第2期121-129,共9页Acta Seismologica Sinica

摘　　要：利用由4台DCS—302型数字磁带记录加速度地震仪组成的临时地震观测台网获得的记录,对1985年4月18日发生在云南省禄劝县的M_s6.1地震的部分余震作了精确定位.采用直接从条件方程求最小二乘解的方法处理了观测数据,并就算法的简单性和精度的评估等问题将这个方法与阻尼最小二乘法和奇异值分解法作了比较.所得出的28个余震的震中分布在洗马河、九龙河及数条北西向和北东向断裂所围成的区域内.其空间分布显示了这些余震的发生与走向为北东向断层的密切关系.Based on the cassette tape readings acquired from a temporary seismic network of 4 digiatal DCS-302 seismometers,the detected aftershocks are determined of the M 6.1 Luquan earthquake which occurred on 18 April 1985 in Luquan County of Yunnan Province. An alternative algorithm of least squares solution to the hypocenter parameters without normalizing the observation equations is used in locating the events. The advantage of the proposed algorithm over the damped least squares method and the singular value decomposition method is assessed in terms of processing simplicity and computation precision. The 28 aftershocks determined are located in an area roughly surrounded by the Xi Ma River,the Jiu Long River,and a number of NW and NE trending faults. The space distribution of these events suggests that they are closely related to the faulting activities of the NE direction.

关 键 词：禄劝地震 地震定位 最小二乘法 

分 类 号：P315.63[天文地球—地震学]