1996年2月3日云南丽江7.0级地震

THE M 7.0 LIJIANG EARTHQUAKE IN YUNNAN ON FEBRUARY 3, 1996

１９９６年２月３日１９时１４分１８１秒，云南省丽江与中甸交界的丽江县境内（北纬２７°１８′，东经１００°１３′）发生７０级强烈地震。大震发生后，云南省地震局立即按《云南省破坏性地震应急预案》启动一类大震对策，成立地震前后方两个指挥部，全面开展震情现场监视、地震灾害损失评估、科学考察和宣传工作。准确地预报了２月５日６０级、２月６日５７级、２月７日５４级强余震，及时科学地完成了灾情调查和震害损失评估报告，为各级党委政府领导指挥地震应急抢险、恢复重建工作提供科学依据。对于丽江７０级地震的预测预报实践，经国家地震局及有关专家确认：①中期（１—３年）和中短期（１年尺度）预报较为准确；②震前短期预测向省政府打了一定招呼；③临震预报地点判断失误。本次地震由两次破裂构成，初始破裂从微观震中大具向东南方向扩展约１０余公里，以倾滑为主；主破裂方向偏转至近南北向，由北向南扩展近２０公里，其位置与方向与玉龙山东缘山前断裂基本一致，并在地表形成三段断续和长约３０公里的破裂带，总体走向Ｎ１０°—１５°Ｅ，具左旋斜滑特征。综合分析认为。

A strong earthquke of M 7.0 occurred in Lijiang county bordered on Zhongdian (27°18′N,100°13′E)at 18.1', 19: 14 on Feb.3, 1996. Seismological Bureau of Yunnan Province initiated immediately the countermeasures of great earthquake at the first class after the shock according to“Emergency Measures for Destructive Earthquake in Yunnan Province”, set up both the front and rear command posts and carried out seismic monitoring comprehensively on spot, earthquake disaster and loss assessments, scientific investigation and seismological propaganda, and the strong aftershocks with M 6.0 on Feb. 5, M 5.7 on Feb.6 and M 5.4 on Feb. 7 were predicted comparatively accurately and the report about the earthquake disaster survey and loss assessment was completed timely and scientifically by SBYP, which provided scienific basis for the earthquake emergency and rescue measures and recovery and rebuilding works under the lead and command of party committees and Governments at different levels. The prediction practice of the M 7.0 Lijiang earthquake has been confirmed by State Seismological Bureau and relative specialists; it includes 1. comparatively accurate medium term (1-3 years) and medium-short term (1 year) predictions; 2. the short-term prediction prior to the event has let the Government of Yunnan Province know to a certain degree; 3. an error of jubgment on location in the impending earthquake prediction. This event consists of the two ruptures; the initial rupture spreads to over 10 Km from the micro-epicenter, Daju to southeast, taking dip slip as dominant; the principal rupture, the orientation of which turned to near northsouth, spreads to about 20 Km from north to south, with the location and orientation roughly in accordance with ones of the piedmont fault, east edge of Yulong mountain and forms the rupture zone consised of three segments in surface, with discontinuous length of about 30 Km, total strike of 10°N-15°E and left-lateral oblique-slip character. Synthetical analysis thinks vertical force played a leading role in the seismic rupture process.