新疆伽师强震群强震主破裂面走向初探

PRELIMINARY STUDY ON STRIKE OF MAIN RUPTURE SURFACE OF JIASHI STRONG EARTHQUAKE SWARM

摘要:

1997年1月21日~1998年8月27日新疆伽师发生了包含9次6级地震的强震群,震源机制解表明有NE向和NW向两个节面.有观点认为主破裂面为NNW向.本文通过数字地震台阵的余震序列精确定位、震源破裂过程及滑动方向、震群空间分布图像、地震烈度等震线长轴走向和微、宏观震中动态变化方向等多种方法分析后,综合判定9次6级地震的主破裂面走向极可能为北东方向.

Abstract:

From Jan. 21, 1997 to Aug. 27, 1998, the strong earthquake swarm including 9 events of M_S 6 occurred in Jiashi, Xinjiang Uygur Autonomous Region. The focal mechanism solutions show that 9 events have both two nodes of NE and NW. In some people's opinions, the main rupture strike of the swarm is NNW direction. In this paper, through analysis on the precise location of aftershock sequences recorded by digital seismic array, focal rupture process and slipping directions, spatial distribution image of earthquake swarm, long-axis strikes of intensity isoseismal line, and dynamic change trends of micro-macro epicenters, the conclusion that main rupture strike is most likely NE direction is Obtained.