江苏海安顾庄观测站井下地电阻率观测影响系数分析

Influence Coefficients Analysis of Down Hole Resistivity Observation in Hai'an Seismic Station,Jiangsu Province

根据地电阻率影响系数理论,分析了江苏省海安顾庄观测站井下地电阻率台站在对称四极地电阻率观测时,每层介质的影响系数随深度和极距的变化情况,并对该台站的观测装置系统进行评估.结果表明:①与地表NS向观测相比,海安顾庄观测站井下观测装置能较好地抑制地表干扰;②海安顾庄观测站井下观测的供电极距AB/2在100~235 m,电极埋深H在28~34 m较合理.该分析结果可为具有类似台址电性结构的地电阻率台站实施井下观测提供一定的参考.

Based on the theory of influence coefficient of resistivity observation,the variation of influence coefficient of each layer was analyzed,with the change of depth and polar distance for symmetrical quadrupole apparent resistivity observation system at Hai’an Guzhuang deep-well resistivity observation station in Jiangsu Province,and the observation device system of this station was evaluated.The results showed that:①Compared with the surface NS observation,the deep-well resistivity observation device of Hai’an Guzhuang observation station could better suppress the surface interference;②It is reasonable with the power supply electrode distance AB/2 observed at Hai’an station down hole resistivity between 100mand 235mand the electrode buried depth H between 28mand34m.The analysis results could provide some reference for down hole resistivity observation at stations with similar electrical structure.