1970年以来中国大陆25次6.8级以上地震前态矢量异常特征研究

Characteristics of state vector anomaly before 25 earthquakes(M≥6.8) in China′s mainland since 1970

利用态矢量方法对中国大陆1970年以来25次6.8级以上地震进行了较为全面的分析研究,结果表明,19次地震前3年内态矢量出现明显异常,其中10次地震发生前60天内态矢量有明显的变化,只有6次地震前态矢量变化不明显。由此认为态矢量方法对强震具有一定的中期和短临预测能力。研究结果还表明,相对于态矢量增量的模、态矢量方向的改变等参量,态矢量的模在震前的变化更为敏感,此外,对于相同震级的地震,最佳扫描区域尺度大小不一,并对这些现象进行了一定的解释。

25 great earthquakes （M≥6.8） in China＇s mainland since 1970 are studied by u sing the prediction approach of slate vector in this paper. The results show that apparent anomalies occur within 3 years before 19 earthquakes among 25, of which apparent anomalies occur within 60 days before 9 among 19. This implies that the state vector could be used as a kind of methods for mid term and short-term earthquake prediction. The results also show that the module of state vector is more sensitive than other parameters staled in this paper. The results show at the same time that there are different best scan zones rela tive to the same magnitude earthquakes occurred in different locations. The causes of these phenomena are discussed in this paper.