震源机制一致性参数方法在台湾地区的应用研究

Application of Focal Mechanism Consistency Parameter Method in Taiwan Region

基于台湾地区1977—2022年568次M_(W)4.5以上地震的震源机制解资料,反演其一致性参数应力张量方差Variance的空间分布及Misfit角的时序变化特征。结合台湾地区历史震例研究表明:台湾M_(S)≥6.0地震多数发生在应力张量方差Variance的低值区或高低值的过渡区,发震时间多为Misfit角出现≤40°过程中的几天至几年尺度。此外,该方法在台湾中央山脉以东地区通过R值检验,最佳预测时间为150 d,因此,在台湾中央山脉以东地区震情跟踪的中期预测指标中可推荐使用。

Based on the focal mechanism solution data of 568 earthquakes with M_(W)≥4.5 in Taiwan from 1977 to 2022,the spatial distribution of the consistency parameter stress tensor variance and the time series variation characteristics of the Misfit angle were inverted.Combining with the study of historical earthquake cases in Taiwan,it is shown that most of the earthquakes with M_(S)≥6.0 in Taiwan occur in the low-value area or the transition area between high and low values of the stress tensor variance,and the earthquake occurrence time is mostly a few days to several years when the Misfit angle≤40°.In addition,this method has passed the R value test in the east of central mountain range of Taiwan,and the best prediction time is 150 days.Therefore,it can be recommended for medium-term prediction indicators for earthquake tracking in the east of central mountain range of Taiwan.