水平层状介质中深埋装置系统地电阻率影响系数特征研究

Characteristics of the influence coefficient in the cases of deeply-buried configurations for geoelectrical resistivity observation

讨论了地电阻率观测装置系统深埋条件下的影响系数特征.采用这类装置的目的在于减小甚至消除来自表层产生的干扰,以提取深部可能的地震信息.采用水平层状介质模型,应用边界积分方程法计算了不同装置埋深、不同装置参数下的影响系数及其与结构参数间的关系.结果表明,不同地层影响系数的大小与电阻率结构、电极埋深、供电极距有密切且复杂的关系.这表明为了有效地压制表层干扰并观测到底层变化,首先需要精细地探查测区电性结构,然后在此基础上,通过理论分析确认装置埋深及选定装置参数.

This paper deals with the characteristics of the influence coefficient in the cases of array deeply buried for geoelectrical resisitivity observations,which has been developed in recent years and aimed at decreasing or even eliminating the interference from the top layer and exacting the possible earthquake-related information from depth.The horizontal layered model has been taken into con-sideration in the study and the algorithm of the boundary integral equation has been adopted for calculating the influence coefficient,when the configuration of the array is located in the different depths under the ground surface.The calcu-lations demonstrate the features that influence coefficient has been closely con-trolled by the structure parameters of the model,the depth of the buried array and the separation of the array.The results in this paper strongly suggested that one must pay great attention to the following steps in the studies of the deeply-buried array：the first,exploring finely the structure parameters of true resistivity in the observed media,and the second,confirming the depth for the array having been located and the configuration parameters corresponding to the model structure.