摘要
20 0 3年 2月 2 4日新疆巴楚—伽师发生 6 .8级地震 ,震中位于 1997— 1998年伽师 9次 6级地震分布区域的东南端。这次 6 .8级地震的余震呈北西向分布 ,与极震区长轴走向一致 ,截止 2 0 0 3年4月 15日最大余震为 5 .8级。震源机制解初步分析结果为 :震源断错属逆倾滑性质 ,近南北向的节面可能为主破裂面 ,主压应力 P轴方位为北西西。 6 .8级地震发生在 2 0 0 3年度全国划定的 6— 7级地震危险区内。震前根据新疆震情的发展 ,新疆地震局预报中心在对 2月份的震情判定中明确提出“2月或稍长时间新疆两个地震重点危险区有发生中强震的可能”,预测意见对应较好。
An earthquake of M-S 6.8 occurred between the Bachi county and Jiashi county of Xinjiang Uygur Autonomous Region on Feb. 24, 2003. Its epicenter locates in the southeast of the seismic region in Jiashi where 9 events of M-S≥6 occurred from 1997 to 1998. The aftershocks distributed along NW direction, identical with the direction of the long axis of meizoseismal area. The maximal magnitude of aftershocks was M-S 5.8 up to Apr.15,2003. The focal mechanism solution shows that the type of focal dislocation is dip-slip reverse fault, and the main rupture surface may be the near-NS-direction nodal plane, with the NWW-direction P axis azimuth of main compressive stress. The earthquake of M-S 6.8 occurred in the 2003 forecasted danger regions of M-S 6-7 earthquakes. According to the seismic situation, the Prediction Center of Xinjiang Seismological Bureau put forward the following suggestion before the shock in February, 2003: it is probable to occur moderate-strong event in the two key seismic danger regions of Xinjiang during the February of 2003 or longer. The suggestion was proved later.
出处
《内陆地震》
2003年第2期170-175,共6页
Inland Earthquake
关键词
地震序列
震情跟踪
巴楚—伽师6.8级地震
新疆
Earthquake sequence
Seismic situation tracing
Bachu-Jiashi MS 6.8 earthquake
Xinjiang
