日、月对孕震区的水平引潮力与震源机制的关系  

Relation between the horizontal tide force which the sun and moon imposes on the seismogenic zone and the focal mechanism

作　　者：李延兴[1] 许力生[2] 胡新康[1] 帅平[1] 耿洪[1] 张中伏[1] 

机构地区：[1]中国地震局第一地形变监测中心,天津300180 [2]中国地震局地球物理研究所,北京100081

出　　处：《地震》2001年第1期1-6,共6页Earthquake

基　　金：国家重点基础研究发展规划项目!(G1 9980 4 0 7)资助

摘　　要：根据计算日、月对孕震区水平引潮力方位角的表达式及美国哈佛大学提供的全球 Mw≥7.0的矩张量地震目录 ,选取了 1 980年 1月至 1 999年 1 2月全球发生的 (Mw≥ 7.0 ) 2 4 2次地震。利用地震目录中提供的地震矩张量参数 ,计算了每次地震发震应力场 P轴、T轴的方位角。同时计算了每次地震时日、月对震中区水平引潮力的方位角。将此方位角与 P轴、T轴以及二组断层面的走向进行对比分析。结果表明 ,日、月对震中区的水平引潮力方向与 P轴、T轴的方位角及二组断层面的走向互相平行或互相垂直 ,其平行或垂直的一致性非常好。平行或垂直相差在1 0°、2 0°、30°之内的发震概率分别达到了 0 .41 4、0 .736、0 .945。这个结果表明 ,日、月对孕震区的水平引潮力与大地震的发生密切相关。并进一步讨论了日。Based on the earthquake catalogue of the seismic moment tensor supplied by Harvard University, 242 earthquakes (M W ≥7.0) occurred on the whole globe during the recent 20 years (from January 1, 1980 to December 31, 1999) are selected. Thus the azimuth expression of the horizontal tide force in the seismogenic regions is obtained in this paper. The axes P and T azimuth of each earthquake stress field may be derived from the seismic moment tensor parameters from the earthquake catalogue, and the azimuth of the horizontal tide force relative to the sun and moon imposes in the epicenter region, may also be calculated. The azimuth of the horizontal tide force is compared respectively with those of the axes P and T and two groups of fault trends, and it can be shown that they are almost parallel or perpendicular one another and the parallel or perpendicular accordance is very well. The probabilities, for the great earthquake occurrence with the parallel or perpendicular difference within 10°, 20°and 30°, are respectively more than 0.414, 0.736 and 0.945. The result shows that there may be a close relation between the sun, moon, the horizontal tide force in the seismogenic regions and the great earthquake occurrence. In this paper, it is further studied that the horizontal tide force might play a controlling role in the great earthquake occurrence.

关 键 词：水平引潮力 震源机制 孕震区 调制作用 天体 地壳 发震应力场 

分 类 号：P315.72[天文地球—地震学]