【摘要】 对2008年汶川8.0级地震前周边远近台站的电阻率异常特征进行了分析。离震中400km内的郫县、甘孜、冕宁、武都四个台站基本都存在1年以上的中期异常;距震中较远的兰州台和天水台则出现了短临异常变化。总结了我国9次7级以上大震前地电阻率台观测资料,认为电阻率异常形态以负异常为主,在极值附近或转折恢复过程中发生地震。震中附近台站多数有异常,大部分为一年以上中期的变化,年变形态消失;震前能观测到短临变化;一般在极值点附近发震。较远台站部分存在异常;短期和临震异常变化相对增多;在回升过程中或异常恢复后发震。更多还原

【Abstract】 The anomalous change features of resistivity in the monitoring stations,which are located near or far from the epicenter of Wenchuan M8.0 earthquake in 2008,are analyzed. There were intermediate-term anomalies for more than one year at Pixian,Ganzi,Mianning and Wudu stations which are less than 400 km from the epicenter,and short and imminent-term anomalies even existed at Lanzhou and Tianshui stations which are far from the epicenter. Also the data of electrical resistivity in past several tens years for 9 large earthquakes with M≥7.0 are summarized. The result shows that most anomalous resistivity changes before large earthquake are negative and the value curves are decline,earthquake often occur near the position of extremum or in resuming process. The anomalies can be found at most stations near epicenter,lasting for more than one year with annual rariation disappear. The short and imminent-term change can be observed also. For far stations,only some have the anomaly,mainly are short and imminent,and event occurs in or after resuming process.更多还原