断层活动协调比在地震预测中的应用

为了有效捕获潜在震源区前兆变化信息与断层应变积累状态, 本文应用断层活动协调比概念, 对川滇地区和首都圈地区断层活动进行了分析。 结果表明: ① 丽江7.0级地震前震源区经历了至少有10多年的断层闭锁阶段, 不同观测场地协调比变化的时空差异性特征可能反映了震源区以及外围的异常演化特征; ② 断层活动协调比参数可帮助判识断层活动的性质, 当基线、 水准原始观测曲线出现显著的变化, 而协调比处于正常水平时, 断层活动即为无应变积累的自由蠕滑; ③ 断层活动协调比在大部分地震前都出现一定的离散性变化, 对分析强震前的断层活动性质和应变积累状态以及地震中长期预测具有一定的参考价值。

Application of Fault Motion Coordination Ratio in Earthquake Prediction

In order to effectively obtain earthquake precursors of potential seismic source and state of fault strain accumulation,we analyzed the fault movements in Sichuan-Yunnan region and the Capital area of China applying the concept of fault motion coordination ratio(FCR).The results show that: ① The fault had been locked for at least ten years at the source region of M7.0 Lijiang earthquake.The different characteristics of spatial and temporal of FCR change among several surveying sites,which may reflect the evolution of abnormal changes in the seismic source and external regions.② The nature of fault motion can be identified using parameter of FCR.Fault movement is in free and non-strain accumulation state if FCR is in normal level,even though baseline and level surveying curve showed abnormal changes.③ Certain kind of discrete changes of FCR appear before the majority of great earthquakes,which has certain values in analyzing the nature of fault motion,strain accumulation state and long-term earthquake prediction.