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将遗传算法应用于地震矩张量解的反演问题．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７．３级地震及其邻近地区（北纬２１°～２６°，东经１１５°～１２０°）ＭＬ≥５．８共５个地震的矩张量解及震源参数．在５个地震中，１９９４年９月１６日台湾海峡７．３级地震是我国东南沿海地区自１９１８年南澳７．３级地震以来最大的一次地震．结果表明：这次７．３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像．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，这次地震是受菲律宾板块向欧亚板块北西向挤压的力源控制．但从Ｐ轴接近竖直而Ｔ轴接近水平看，这是一次强烈拉张性的正断层．其它４个强震震源机制解与７．３级大震相互差别较大．这些地震震源机制解的复杂性表明了海峡地震序列发展过程是比较复杂的．
Applying Genetic Algorithm to Inverse Problem of Moment Tensor Solution of Earthquake. Based on the data of P wave in digitalized network and the data of initial P wave in Taiwan network, the magnitude 7.3 of the Taiwan Strait earthquake on September 16, 1994 and its adjacent areas (latitude 21 ° ~ 26 °, longitude 115 ° ~ 120 °) ML≥5.8 A total of five earthquakes moment vector solution and source parameters. Among the five earthquakes, the magnitude 7.3 earthquake in the Taiwan Strait on September 16, 1994 was the largest since the magnitude 7.3 South Southeastern Japan earthquake in 1918 in the southeast coast of China. The results show that the moment tensor solution of the magnitude 7.3 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 the distribution 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. It seems that the earthquake was controlled by a force source that squeezed the Philippine plate northwest of the Eurasian plate. However, when the P-axis is close to vertical and the T-axis is close to horizontal, this is a strong extensional normal fault. The focal mechanism solutions of the other 4 strong earthquakes are greatly different from those of the 7.3 magnitude earthquakes. The complexity of the focal mechanism solutions for these earthquakes shows that the development of the seismic series in the Straits is more complicated.