地震学报2019，Vol.41Issue(2)：207-218,12.
2018年5月松原MS5.7地震序列发震断层及应力场特征
Characteristics of seismogenic faults and stress fields of the Songyuan MS5.7 earthquake sequence in May 2018
摘要
Abstract
In recent years, moderate-strong earthquakes in Songyuan area of Jilin Province are active. Studying the fault structure and stress field characteristics of the earthquake sequence in Songyuan area is of great significance for scientific understanding of the earthquake-preserving environment in Northeast China and earthquake prevention. The ML≥1.0 earthquakes are relocated by the method of double difference relocation, the focal mechanism solutions of the strong earthquakes are determined by the CAP method, and the stress field is determined by the FMSI method.According to the results, we realize that: ① The Songyuan MS5.7 earthquake sequence occurred at the intersection of the Second Songhuajiang fault trending NW and Fuyu-Zhaodong fault trending NE. The results of earthquakes relocation are analyzed along the two faults. The length of the NW axis is about 5 km, the same as to NE axis. The epicenters on the profile of NW axis have a high inclination distribution, while the NE axis is uniform. ② The focal mechanism solutions of four ML≥3.7 earthquakes are all of strike-slip type with high dip angles and good consistency: The strike of nodal plane Ⅰ is NE, and the other is NW. The focal mechanisms of the moderate-strong earthquakes are basically consistent with the Second Songhuajiang fault, and it is concluded that the Second Songhuajiang fault is the seismogenic fault of the Songyuan MS5.7 earthquake; ③ The principal compressive stress azimuth and the inclination angle of Songyuan area are N86°E and 7°, respectively, and the principal tensile stress azimuth and the inclination angle are N24°E and 71°, respectively. The regional stress field in Songyuan area is controlled by both large-scale plate tectonic movement and regional tectonic movement. Under the westward subduction of the Pacific Plate, the Northeast Asia Plate’s principal compressive stress near the EW direction is generated, which is controlled by the surrounding geological structure. The strike-slip type earthquake is prone to occur at the intersection of the NE-trending fault and the NW-trending fault in the Songliao basin, while the 2018 Songyuan MS5.7 earthquake is a moderate-strong earthquake that occurred under the control of such tectonic action.关键词
松原地震/ 双差定位/ 震源机制解/ 构造应力场/Key words
Songyuan earthquake/ double-difference relocation/ focal mechanism solutions/ tectonic stress field/分类
天文与地球科学引用本文复制引用
李君,王勤彩,郑国栋,刘庚,周辉,周聪..2018年5月松原MS5.7地震序列发震断层及应力场特征[J].地震学报,2019,41(2):207-218,12.基金项目
地震科技星火计划（XH18070，XH17060Y）、国家重点研发计划“鄂尔多斯活动地块边界带地震动力模型与强震危险性研究”子课题（2017YFC1500102）、中国地震局地震预测研究所基本科研业务费专项（2018IEF010203，2014IES010204，2015IES0404）联合资助 （）
