多方法联合分析未来地震发生趋势

综合多种前兆方法分析地震活动规律,研究目标地区未来地震发生的趋势。首先采用图像信息法(PI)进行扫描,从长期尺度上找出研究区域内地震活动异常的地区,并结合相关的活动断裂分布及区域地震活动确定未来地震的发震危险区;然后采用加卸载响应比(LURR)、态矢量(SV)、矩张量加速释放(AMR)等中短期前兆方法分析这些区域的地震发生可能,并对地震发生的相关信息做进一步估算;在空间上实现向地震危险区域的逐渐逼近,时间上实现从长期预测到中短期预测的自然过渡。作为回顾性震例研究,我们对近3年来发生在中国西部的强震(ML6.5)进行了检验,结果表明,相对于单一算法而言,将不同前兆方法适当组合结合能够更为明确地为未来地震危险性评估提供信息和约束。

Multi-method Linked to Study Future Seismic Tendency

Several earthquake precursory methods are combined to investigate the future large earthquake potential in the research region.First the Pattern Informatics(PI) method is used to quantify localized changes surrounding the epicenters of large earthquakes and to objectively quantify the anomalous areas(hot spots) of the upcoming events.Then the seismogenic regions of the ensuing large events are delineated by integrating with associated active fault zones.Finally,the earthquake potential in the region is evaluated using 3 other short-to-intermediate-term earthquake prediction methods(Load Unload Response Ratio,State Vector,and Accelerate Moment Release).In the spatial scale the approach can achieve the gradual approximation to the seismogenic zones;while in the temporal scale,the approach can achieve the natural transition from the long term to the short-to-intermediate-term earthquake forecast.As a retrospective study,the large earthquakes(ML>6.5) occurred in western China in last 3 years are examined.The results may suggest that,rather than a single precursory method,the multi-methods combined approach can be a useful tool to provide stronger constraints on forecasts of future large events.