安徽省数字化地电阻率观测数据的干扰分析与处理方法

Interference Factors and Processing of Digital Geoelectrical Resistivity Data in Anhui Province

近年来安徽地区地电阻率观测多次出现异常数据,同期间省内发生了多次M_S3.0以上地震,我们对安徽省观测较好的几个台站数据进行年变化特征、干扰因素的分析,发现水位、降雨是影响地电阻率数据变化的主要因素,通过以月为窗长的回归拟合分析进行水位的干扰消除,计算的残差值能有效地消除地电阻率年变化干扰,运用消除干扰后的曲线对近期发生的地震进行分析,发现霍山M_S4.3和阜阳M_S4.3等地震前未出现明显趋势性前兆异常,临近台站出现的异常变化可能与该区域的地下水位干扰性变化有关。

In recent years, many abnormal geoelectrical resistivity data appeared in seismic stations, while magnitude Ms≥3.0 earthquakes have occurred many times in Anhui prov- ince. We analyzed annual change characteristics and interference factors of geoelectrical re- sistivity data in many high quality stations, and found that water level and the rainfall were the main factors influencing geoelectrical resistivity data changes. Furthermore, we had the interference analysis for water level through calculating regression fitting for the window length of a month, so that the calculated residuals can effectively eliminate annual change characteristics, and get the curve to analyze recent earthquakes. Finally, we found that there have no obvious abnormal images before the Huoshan and Fuyang 4. 3 earth- quakes.