本文通过计算汶川8.0级主震及20次Ms≥5.0强余震发震时刻引潮力的方位、大小及变化率,并对比其破裂方式,发现11次逆冲型地震其发震时刻的水平引潮力方位和主压应力轴P轴有6次夹角在33°之内;8次走滑型地震,其发震时刻垂向引潮力都处于向上的峰值区间;而2次具有张性正断分量的地震,发震时刻垂向引潮力都处于向下的峰值区间.根据以上的统计特征,本文就引潮力对三种破裂类型在汶川主震及强余震中可能的触发机制进行了探讨.%By calculating the azimuth, phase angle and change rate of tide force at the times of occurrences of the Wenchan Ms8.0 earthquake and 20 Ms≥5.0 aftershocks, and contrasting with their rupture types, we find that the angles between the direction of the horizontal tidal and compressive principal stress are within 33° for 6 earthquakes in 11 reverse earthquakes. All of the vertical phase angles of 8 strike-slip earthquakes are in the up peak period, and 2 normal earthquakes＇ vertical phase angles are in the downward peak. Based on statistical phenomenon, we discussed the mechanism of tidal force triggering of the Wenchuan Ms8.0 Earthquake and its strong aftershocks.
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