青海乐都断层气氡的年变异常特征分析

Analysis on the anomaly characteristics of fault gas radon annual variation in Ledu of Qinghai

在地震预报研究中,断层气观测具有重要意义。以青海乐都断层气氡的观测资料为基础,结合该测点的环境变化特征、地球化学特征、震例等及其机理分析,认为乐都断层气氡在门源6.4级地震前有较好的前兆指示意义。2017年,因附近河道施工改造,影响断层气的运移路径,引起观测数据年形态改变。这些现象表明,该测点位于构造活动敏感部位,具有较好的映震效能,当异常出现时,排除环境及观测系统干扰后,可作为震情跟踪的重要依据。

Fault gas observation plays an important role in earthquake prediction.This paper studies further and discusses on long-term observational data of fault gas radon in Ledu.In conjunction with the analysis on observation environment interference,geochemical characteristics and so on,it is found that fault gas radon reveals obvious precursor characteristic before the Menyuan Ms6.4 earthquake,In 2017,the annual variation was broken due to river reconstruction and the fault gas migration path was affected.These phenomenon indicate that fault gas radon of Ledu of Qinghai is located in the area of tectonic activity.It′s able to reflect earthquake precursors if we can exclude the interference from the observation working system and environment through formation mechanism analysis,hence applicable to earthquake monitoring.