摘要
北京时间2016年1月21日1时13分,在青海省门源县发生M_S 6.4地震。利用喜马拉雅台阵二期部分台站和青海地震台网震后2个月的震相观测数据,采用双差定位方法,对门源地震序列进行重定位研究。重定位结果表明,余震序列呈北西向分布,大致平行于冷龙岭断裂走向,余震展布长度约12 km,90%的余震发生在5—13 km深度范围内。结合震源机制,认为此次地震为向西南倾的高倾角逆冲地震,发震断层为冷龙岭北东侧的次级断裂,断层面走向约131°。震源深度剖面显示,门源地震的余震分布与常见的逆冲型地震余震分布存在差异,可能与该区域深部地质构造和介质结构异常复杂有关。
At 113 on 21 January 2016 （Beijing time）, an MS 6.4 earthquake struck Menyuan Countyof Qinghai Province. Using the earthquake phase data recorded by Himalaya seismic array andQinghai seismic network, we relocated the aftershock sequence of Menyuan earthquake withdouble-difference location algorithm. The relocation results show that the aftershock sequenceis in northwest direction, which is roughly parallel to the direction of the Lenglongling fault. Thelength of the aftershock zone is about 12 km, and 90% of the aftershocks occur in the depth rangeof 5 to 13 km. Combined with the focal mechanism, we propose that the thrust earthquake dips tosouthwest with high angle and the seismogenic fault is a secondary fault on the northeast side ofthe Lenglongling fault. The strike of the seismogenic fault is about 131°. Focal depth profiles showthat the aftershock distribution is different with that of typical thrust earthquakeswhich may berelated with the complex geological and medium structure in this region.
出处
《地震地磁观测与研究》
2016年第5期15-18,共4页
Seismological and Geomagnetic Observation and Research
基金
地震行业专项(201308011)
中国地震局地球物理研究所基本科研业务专项(DQJB14C08)
关键词
门源地震
余震序列
双差定位
冷龙岭断裂
Menyuan earthquake,aftershock sequence,double-difference location,Lenglongling fault
