青海玉树M7.1地震前地下流体异常分析

ANALYSIS OF UNDERGROUND FLUID ANOMALY BEFORE YUSHU M7.1 EARTHQUAKE IN QINGHAI

利用原始数据和小波分析方法对青海省地下流体资料进行分析,提取玉树7.1级地震前观测数据的异常。结果表明:①选取的8个测项中,有4个测项出现了异常,占50%。异常分布范围较大,震中距最大达480 km,异常都发生在震前8个月之内。②从原始数据看,玉树水温、德令哈水温和玉树水位震前异常明显,其中德令哈水温原始数据在震前12天出现快速上升的短临异常变化。③从小波分析的结果来看,有4个测项在震前出现明显异常。异常过程与发震时间的关系为异常开始—异常峰值—异常结束—恢复正常后发震。

In this paper,the original data and wavelet analysis methods are used to analyze the underground fluid data in Qinghai to extract the anomalies of the observed data before Yushu M 7.1 earthquake.The results show that:①Among the 8 test items selected in this paper,4 of them appears abnormal,accounting for 50%.Among them,2 anomalies are the water temperature anomaly,1 is the radon anomaly and 1 is the water level anomaly.The distribution range of anomalies is large,and the maximum epicenter distance is 480 km.All the anomalies occurred within 8 months before the earthquake.②From the original data,the water temperature of Yushu,Delingha and the water level of Yushu before the earthquake were unusually obvious.Among them,the original data of water temperature in Delingha showed a short-term anomalous rapid rise change in the 12 days before the earthquake.③According to the results of wavelet analysis,there are four items with obvious anomalies before the earthquake.The relationship between the abnormal process and the earthquake initiation time is the beginning of the anomaly-the peak of the anomaly-the end of the anomaly-the earthquake initiation after the anomaly return to normal.