基于Fisher判别方法计算断层破裂面积的研究

Computation of Fault Rupture Area Based on Fisher Discriminant Method

实时计算并快速得到破坏性地震断层破裂分布范围可及时向潜在破坏区发出预警信息,为大震预警提供重要依据。本研究基于我国发生的5个重大破坏性地震的强震观测数据,利用Fisher线性判别方法,拟合出能够有效将台站记录进行分类的线性判别函数。应用该方法对2008年汶川地震断层破裂面积进行模拟计算,持续更新震后5~74s断层破裂面积,反演得到的断层破裂分布区域与野外地质调查结果基本一致。通过对实际震例测试分析表明,该方法反演的结果能够较准确地覆盖断层破裂区域,震后快速计算的断层破裂分布区域能够为地震预警及后续的烈度速报产出结果进行实时修正。

Real-time computation and rapid determination of the distribution range of destructive earthquake fault ruptures are critical to the early warning of major earthquakes and for the timely dissemination of early warning information to potentially affected regions.Utilizing strong earthquake observation data from five significant destructive earthquakes in China,this study employs the Fisher linear discriminant method to establish a discriminant function capable of effectively classifying station records.The method was applied to simulate the fault rupture area of the 2008 Wenchuan earthquake,achieving continuous updates on the rupture area within 5~74s post-earthquake.The inversion results were found to be largely consistent with field geological survey outcomes.Through testing and analysis of actual earthquake cases,this study demonstrates that the inversion results from the applied method can more precisely delineate the fault rupture distribution area.Such precision has the potential to enhance the accuracy of earthquake early warning systems and subsequent rapid intensity reports.