【摘要】 对宝昌台地电阻率日变、年变和长期变化3种典型变化进行了分析,结果显示:整点值曲线存在明显的日变形态,可能是由外线系统对地绝缘不良造成的;地电阻率年变主要是由气象因素年变引起的,其中温度和降雨量贡献基本相同;地电阻率NS测道存在长期下降变化,而EW测道没有,这一现象与测区内水位、温度和降雨量等长期变化无关,主要是由于受到台站所在区域近EW向应力长期、持续作用引起的,并不对应地震。更多还原

【Abstract】 Three kinds of typical variations of earth resistivity at Baochang Station are analyzed,which includes daily,annual and secular variations.The result shows that there exists significantly daily variation morphology in the curve of earth resistivity hour-point values,which is caused by unstable insulating properties of transmission lines.The annual variation of earth resistivity is mainly caused by meteorological factors including temperature and rainfall.There exists secular oblique-type variation only in the curve of earth resistivity in NS direction,which is not related with the secular variation of water level,temperature,and rainfall etc..However it is mainly caused by the long-time prolonged action of stress in EW direction,which is not corresponding with the earthquake.更多还原