前兆地电阻率资料处理的剥皮法

在台址下电阻率分层均匀的前提下，针对我国绝大多数前兆地电台单极距观测的事实与现状，提出一种试图从这种观测所获得的视电阻率时间序列中识别电阻率表层变化和深部变化的等效模型方法．分析表明，在保持布极方式和观测结果不变的前提下，任意多层的地电结构都可以视为一个二层地电结构——等效模型．本文中，等效模型上层的地电参数（电阻率和厚度）与实际模型第一层相同，下层的地电参数（电阻率）则根据等效要求，由实际模型第二层及其以下各层的地电参数经计算得到，因此，等效模型的下层包含了实际模型第二层及其以下各层的综合影响．初步研究表明，这种方法是可行的． 

THE “PEELING” METHOD TO PROCESS APPARENT RESISTIVITY DATA FOR EARTHQUAKK PRECURSORY MONITORING

Considering the fact that, between two fixed current poles there is only one pair of fixed potential poles used to monitor the resistivity changes under the observatory station which may indicates process of earthquake preparation, based on the precondition that the resistivity structure is 1 dimensional under the observatory station, and by way of equivalent model put forward by the authors, this paper suggests a kind of method trying to identify the resistivity changes in deep layers from that of the shallowest layer. Analysis shows that, to obtain the same measured data with the same array, any a multi layer geo electrical structure can be equivalently seen as a two layer one, we call it equivalent model. In this paper, the resistivity and thickness of the upper layer of the equivalent model are equal to that of the first layer of the original one, the resistivity of the lower layer of the equivalent model is obtained with calculation according to the requirement of equivalence, and one can see the value of it is relevant with the resistivities and thicknesses of all layer of the original model except for the first one, so the resistivity change of the equivalent layer can indicates the synthetic effect of variation of all of the layers of the original model except for the first one. The primary research results show that this method can work well.