【摘要】 使用联合定位方法对2008年5月12日至7月7日ML≥3.0的1 028次地震进行重新定位。针对EVT格式的波形数据,重新求取视出射角参数和到时参数,建立地震波到时与视出射角联合定位方法。视出射角参数对深度较敏感,其联合定位结果能保证经度和纬度方向上的定位精度,特别是能提高对深度的分辨能力。联合定位结果表明,地震序列平均震源深度为12.8 km,深度分布在4~20 km(上地壳),其优势分布在8~18 km,最终汇集到埋深约20 km滑脱面(带)上。地震深度分布显示断层具有分段性,南段以逆冲为主,北段以走滑为主。地震集中位于断层的断坡部位,其断坡部位是应力易于积累的区域(深度约为8~18 km),是主震的发震位置。更多还原

【Abstract】 In this paper 1028 aftershocks from May.12 to Jul.7,2008 have been relocated precisely using Multiparameter Seismic Joint Location method.The parameters of apparent emergence angles and arrival time are extracted according to the wave data with EVT format.The objective function in the method of Multiparameter Seismic Location with apparent emergence angles and arrival time was founded.The apparent emergence angle has the very strong sensitivity to depth.The results of Multiparameter Seismic Location are able to guarantee the accuracy in the directions of latitude and longitude,especially to enhance the depth resolution effectively.The average depth of the earthquake sequence is about 12.8 km,distributing in a range from 4 to 20 km(up crust),and the superiority distribution is from 8 to 18 km,coming together on the detachment plane(belt) with a depth of 20 km approximately.The depth distributing shows segmented fault.The southern and northern segments are thrust and strike-slip respectively.The aftershocks located intensively at the fault ramp,which is the region of stress accumulation(with depth about 8 to 18 km) and the main shock occurred at this location.更多还原