Relocation of the Ms≥2.0 Earthquakes in the Northern Tianshan Region, Xinjiang, Using th

Relocation of the Ms≥2.0 Earthquakes in the Northern Tianshan Region, Xinjiang, Using the

Double-Difference Earthquake Relocation

Algorithm

Wang Haitao;Li Zhihai;Zhao Cuiping;Qu Yanjun

【期刊名称】《中国地震研究（英文版）》

【年(卷),期】2007(021)004

【摘要】We applied the double-difference earthquake relocation algorithm to 1348 earthquakes with Ms≥2.0 that occurred in the northern Tianshan region, Xinjiang, from April 1988 to June 2003,using a total of 28701 P- and S-wave arrival times recorded by 32 seismic stations in Xi njiang.Aiming to obtain most of these Ms ≥ 2.0 earthquakes relocations, and considering the requirements of the DD method and the condition of data, we added the travel time data of another 437 earthquakes with 1.5 ≤ Ms ＜ 2.0. Finally, we obtained the relo cation results for 1253 earthquakes with Ms ≥2.0, which account for 93% of all the 1348 earthquakes with Ms ≥ 2.0 and includes all the Ms ≥ 3.0 earthquakes. The reason for not relocating the 95 earthquakes with 2.0≤ Ms ＜ 3.0 is analyzed in the paper. After relocation, the RMS residual decreased from 0.83s to 0.14s, the average error is 0.993 km in E-W direction, 1.10 km in NS direction, and 1.33 km in vertical direction. The hypocenter depths are more convergent than before and