太原理工大学学报2026，Vol.57Issue(1)：15-27,13.DOI:10.16355/j.tyut.1007-9432.20240056
太原盆地2016年以来中小地震震源机制研究
Focal Mechanisms of Medium-Small Earthquakes in Taiyuan Basin Since 2016
摘要
Abstract
[Purposes]On the basis of previous researches and the latest broadband digital wave-form data from the Shanxi Regional Seismic Network,multiple methods are employed to obtain up-dated focal mechanism solutions for earthquakes with ML≥2.5 that occurred in the Taiyuan basin be-tween May 2016 and December 2023.This work is carried out to further enrich the database of focal mechanism solutions for the Taiyuan basin and to provide reliable key foundational data and support for future scientific research and engineering practices in this region,including studies on earthquake preparation and occurrence mechanisms,seismic trend analyses,and disaster preventions.[Methods]According to the China Earthquake Networks Center(CENC),the focal mechanisms for 68 earth-quakes with magnitudes of 2.5 or above in the Taiyuan basin from May 2016 to December 2023 have been determined by using P-wave initial motion and CAP waveform inversion methods.[Results]The results indicate that the focal mechanisms of recent medium-small earthquakes in Taiyuan basin mainly belong to the normal strike mode,with some beloging to normal strike-slip or strike-slip mode,and few to thrust faulting mode.The directions of P-axis of each seismic source mechanism are mainly concentrated in the NEE-NE-NEN range,which shows the regional variation characteristics in the Taiyuan basin.Meanwhile,the directions of T-axis are concentrated in NW-NWN,showing obvious regional consistency.The results of the regional tectonic stress field with focal mechanism in-version show that the principal stress σ1-axis strikes 45°and the dip angle is 79°,and the principal as-sert σ3-axis strikes 149° and the dip angle is 3°,indicating that the Taiyuan basin as a whole is mainly under action of the horizontal stretching of NW and the vertical extrusion of NE,the principal stress axis shows certain changes in the plane.The above results also show that the tectonic stress field in this area has not changed significantly in recent years and has obvious inheritance.关键词
震源机制解/P波初动/CAP方法/区域构造应力/太原盆地Key words
focal mechanism solution/first motion of P-wave/CAP/local tectonic stress field/Taiyuan basin分类
天文与地球科学引用本文复制引用
李嘉丽,李斌,靳一丹,赵晓云,李自红..太原盆地2016年以来中小地震震源机制研究[J].太原理工大学学报,2026,57(1):15-27,13.基金项目
中国地震局地质研究所国家野外科学观测研究站计划项目(NORSTY2023-01) （NORSTY2023-01）
山西省基础研究面上项目(202303021211037) （202303021211037）
山西省重点研发项目(202202020101009) （202202020101009）
国家自然科学基金(41504051) （41504051）
