天山地区特殊震相的初步研究

PRELIMINARY STUDY OF SPECIAL SEISMIC PHASE IN TIANSHAN AREA

通过对天山地区从2009年1月~2017年7月ML2.7以上3 582个地震的精确分析,选取其中具有PmP、SmS、sPn等特殊震相的地震事件进行研究。研究发现sPn震相在天山地区极少作为初至震相出现,PmP震相出现的概率远大于SmS震相。同时PmP和SmS震相在喀什地区较为集中出现,sPn震相则主要发育在精河县、和静县等地区。通过重新拾取震相和定位,既为天山地区三维走时表的编制提供了数据支撑,也为sPn等特殊震相的进一步研究打下基础。

Based on the accurate analysis of 3 582 earthquakes over ML2.7 in Tianshan area from January 2009 to July 2017, the earthquake events with special phases such as PmP, SmS and sPn were selected to study. It was found that the sPn phase rarely appears as the first arrival phase in Tianshan area, and the probability of the occurrence of the PmP phase was much greater than that of the SmS phase. At the same time, the PmP and SmS seismic phases were concentrated in Kashgar area, while the sPn seismic phase were mainly developed in Jinghe County and Hejing County. By retrieving the seismic phases and locating them again, it not only provided data support for the compilation of three-dimensional travel time table in Tianshan area, but also laid a foundation for the further study of special seismic phases such as sPn.