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根据由南加州地震目录回顾性地震建模及已发表的对新马德里地震带的估算结果,改进型破裂时间法可以作为一种中期地震预测技术用来确定未来主震的地点并预测其大小和时间。提出假设并对先前主震的建模表明本方法预测的主震震级精度达到了约±0.5个震级单位。假设已知前兆序列中最后的事件,则破裂时间误差约是±1.1年。当不知道序列中最后的事件时,预测震级保持相同,但随着时间的推移,往序列中追加事件时,预测时间将需要更新。本方法还可以把主震位置确定在半径为几十公里的一个圆形区域内。我们提供了判定加速序列和主震位置的判据,此判据减少了虚报次数,但也删除了我们估算中的一些主震。根据南加州地震目录,我们估算了发生在1980～1995年间5.5级以上的地震。我们用这些研究结果结合以前的研究结果形成了一个可实际应用(预测未来)的方法。为了捕捉在1998年8月17日以后将发生的未来主震,我们使用改进型破裂时间法搜索了南加州地震目录,结果发现,有一个区域满足了所有的判据,可以由改进型破裂时间法模拟。这个可能发生主震的区域中心在31.43°N,115.47°W,半径为65km 的圆形区域(墨西哥下加利福尼亚北部),预测的震级是6.36±0.55,预测的破裂时间是1998.565(1998年7月25日)±1.127年。随着新的前兆事件的发生,此预测值也将被更新。
Based on the retrospective seismic modeling from the Southern California Seismic Inventory and the published estimates of the New Madrid Seismic Belt, the improved rupture time method can be used as a medium-term seismic prediction technique to determine the location of a future mainshock and predict its size and time. The hypothesis and the modeling of the previous mainshock indicate that the accuracy of the mainshock magnitude predicted by this method reaches about ± 0.5 magnitude units. Assuming that the last event in the sequence of precursors is known, the rupture time error is about ± 1.1 years. When you do not know the last event in the sequence, the predicted magnitude stays the same, but as time goes on, the forecast time will need to be updated as additional events are added to the sequence. The method can also determine the location of the main shock in a circular area of tens of kilometers in radius. We provide criteria for determining acceleration sequences and mainshock positions, which reduce the number of false positives but also delete some of the main shocks from our estimation. According to the Southern California Earthquake Catalog, we estimate earthquakes that occurred above 5.5 in 1980-1995. We use these findings combined with previous findings to form a practical application (predict the future) of the method. In order to capture the future mainshock that will take place after August 17, 1998, we searched for the Southern California earthquake catalog using the improved rupture time method and found that there was an area that met all the criteria and was modified by the improved rupture time Law simulation. This center where the main shock may occur is at a circular region (northern Baja California, 31.43 ° N, 115.47 ° W) with a radius of 65 km and the predicted magnitude is 6.36 ± 0.55 with a predicted rupture time of 1998.565 (July 1998 25 days) ± 1.127 years. This predictive value will also be updated as new precursor events occur.