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1980年1月至1999年12月全球发生的(Mw≥7.0)242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10°、20°、30°之内的发震概率分别达到了0.414、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、月对孕震区的水平引潮力对大地震发生的调制作用。%Based on the earthquake catalogue of the seismic moment tensor supplied by Har-vard University, 242 earthquakes ( Mw ≥7.0) occurred on the whole globe during the recent20 years (from January 1, 1980 to December 31, 1999) are selected. Thus the azimuth ex-pression of the horizontal tide force in the seismogenic regions is obtained in this paper. TheaxesP and T azimuth of each earthquake stress field may be derived from the seismic momenttensor parameters from the earthquake catalogue, and the azimuth of the horizontal tide forcerelative to the sun and moon imposes in the epicenter region, may also be calculated. The az-imuth of the horizontal tide force is compared respectively with those of the axes P and T andtwo groups of fault trends, and it can be shown that they are almost parallel or perpendicularone another and the parallel or perpendicular accordance is very well. The probabilities, for thegreat earthquake occurrence with the parallel or perpendicular difference within 10°, 20°and30°, are respectively more than 0.414, 0.736 and 0.945. The result shows that there may bea close relation between the sun, moon, the horizontal tide force in the seismogenic regions andthe great earthquake occurrence. In this paper, it is further studied that the horizontal tideforce might play a controlling role in the great earthquake occurrence.
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