云南水汞在连发地震前短临异常及震后变化特征

Short-impending anomalies of mercury in groundwater before the continual occurrence earthquake and their later changes in Yunnan, China

通过对1995年5月6日～1996年2月3日发生在云南境内及其中缅边境一带的4组5次M≥6 0级强震的研究,发现水汞在强震连发期都出现短临异常及震后变化;与2001年云南省内6组7次5 0～5 9级中强地震短临异常及震后变化进行比较,结果表明强震连发期水汞的短临异常特征表现为异常台站多、异常幅度大、异常范围广和多台站水汞在异常中发震。中强震连发期水汞的短临异常特征与此相反,表现为异常台站少、异常幅度小、异常范围小和多台站水汞在异常结束后发震。

Based on the study of 4 group of 5 earthquakes with M≥60 which occurred in Yunnan and the boundary of China-Burma from May 6, 1995 to February 3, 1996, we found that there were some short-impending anomalies about mercury in groundwater and later-earthquake changes in continual occurrence period of strong earthquakes. The result shows that the short-impending anomaly of mercury in groundwater in their continual occurrence period characterized more anomaly stations, bigger anomaly amplitude, wider anomaly area and that earthquakes occurred in multi-station anomaly compared to 6 group of 7 medium-strong earthquakes with M50～59 occurred in Yunnan in 2001.On the contrary, short-impending anomalies of mercury in groundwater in continual occurrence period of medium-strong earthquakes characterized fewer anomaly station, smaller anomaly amplitude, smaller anomaly areas and earthquakes would occur after multi-station anomaly ending.