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采用数字化台网Ｐ波波形资料及台湾台网Ｐ波初动方向资料，研究了１９９４年９月１６日台湾海峡７３级地震及邻近地区（北纬２１～２６°，东经１１５～１２０°）ＭＬ≥５８级共５次地震的矩张量解及震源参数。结果表明，这次７３级地震的矩张量解以双力偶成分为主，是断层面接近ＮＷ走向的正断层。断层面的走向与大震前地震的条带分布走向及余震分布显示的破裂图象较相象，震源机制的张应力轴接近水平，近ＮＥ走向；压应力轴几乎垂直，近ＮＷＷ走向，似乎表明这次地震是受菲律海板块向欧亚板块北西向挤压的力源控制。从Ｐ轴接近竖直而Ｔ轴接近水平来看，发震断层为强烈拉张性正断层，可能还同时存在垂直向上的应力作用。其它４个强震的震源机制解与７３级大震的差别较大。这些地震震源机制解的复杂性，表明台湾海峡地震序列的发展过程比较复杂。
Based on the data of P wave in digital network and the data of the initial P wave in Taiwan network, this paper studied the seismic wave of 7.33 Taiwan Strait on September 16, 1994 and its adjacent area (latitude 21-26 °, longitude 115-120 ° longitude) The moment tensor solution and source parameters of 5 earthquakes with ML≥58. The results show that the moment tensor solution of the 73 earthquake is dominated by dual couple components and is a normal fault with a fault plane approaching NW. The strike of the fault plane is similar to that of the strikes of the earthquakes before the major earthquake and the rupture image shown by the aftershock distribution. The focal stress axis of the focal mechanism is close to horizontal and nearly NE-trending; the compressive stress axis is almost perpendicular to the NWW, This indicates that the earthquake was controlled by the force source that the Philippine Sea Plate squeezed northwestward from the Eurasian Plate. Seen from the P-axis close to vertical and the T-axis close to horizontal, the seismogenic fault is a strong extensional normal fault and may have vertical upward stress simultaneously. The focal mechanism solutions of the other four strong earthquakes are quite different from those of the 7.3 earthquakes. The complexity of the focal mechanism solutions for these earthquakes shows that the development process of the Taiwan Strait seismic sequence is rather complicated.