PI算法用在天山地震带的回溯性研究

Retrospective Study on the Application of Pattern Informatics Method in Tianshan Seismic Zone

以天山地震带为研究区域,以该地区1994—2014年发生的MS6.0以上强震为研究对象进行回溯性研究。以截止震级MC为MS4.0,空间网格间距0.4°×0.4°,异常学习时间窗为15年,预测时间窗为4年,系统计算天山地震带1994年以来的"地震热点"图像,分析研究时段内强震前后的PI图像演化过程,并采用ROC方法和R值评分检验,对图像信息方法在天山地区的预测效能进行评分。结果表明:(1)在回溯性研究时段内发生的强震都分布在地震热点上;(2)研究时段内发生的6次6.5级以上地震前均出现不同程度的连续热点异常演化过程;(3)ROC检验和R值评分结果显示,PI算法优于随机预测,PI算法在文章中采用的模型参数对天山地震带MS≥6.0地震具有较好的中长期预测效果。

Pattern informatics(PI)method is an earthquake prediction method based on statistical physics,which has been an active research area in recent years.This method can help to determine whether the seismicity in a grid during a time period deviates from its history and from the average state of the selected study region.In this paper,earthquakes above MS6.0 during 1994-2014 in the Tianshan seismic zone are retrospectively analyzed with the PI method.The results show that(1)most of the studied earthquakes occurred in the seismic regions(hotspots);(2)six earthquakes above MS6.5 have obvious continuous evolution process;(3)the PI method results in reasonable medium and long term prediction of MS≥6.0 earthquakes in the Tianshan seismic zone.