强震前单台测震学异常综合研究——以喀什地震台为例

Comprehensive study on the single station seismic anomalies before strong earthquakes——Taking Kashi seismic station as an example

利用喀什地震台 1 980～ 1 996年单台地震报告资料 ,以震中距 2 0 0 km、1 50 km、1 0 0 km3种空间尺度为界进行地震频度、 b值、缺震、η值、小震调制比、地震危险度 D等方法的计算分析 ,尝试研究提取台站周围 6级以上强震前 ,各种方法的前兆异常特征。研究结果表明 ,强震前多种方法存在不同程度的中短期异常 ,对应地震在 1 50 km范围内 ,远场对应效果不好。多种方法在3种空间尺度条件下的异常反应 。

We tried to refine the comprehensive seismic anomaly characteristics of multiple methods before the large earthquakes (M S ≥6.0) in the range of 150 km from the single seismic station. The seismic frequency, b value, seismic gap, η value, small earthquake modulating ratio and seismic danger degree with the epicenter distances of 200 km, 150 km and 100 km were calculated by using the seismic data of the Kashi seismic station. Through analyzing these components, it is found that there are anomalies with various grades on each method before the strong earthquakes, which corresponded to the strong earthquakes with the range of 150 km. However, there is no good respondence to the strong earthquakes with larger epicenter distances. It is also found that the anomalies of multiple methods with the three distance scales have the empirical correlation with the space extent of the coming strong earthquakes.