高密度电阻率勘测方法分辨率研究与探讨

ANALYSIS OF RESOLUTION INFLUENCE FACTORS OF HIGH-DENSITY ELECTRICAL METHOD AND ITS APPLICATION

随着高密度电阻率法在工程中的应用日益广泛,对分辨率的影响因素分析研究也受到重视。论文以均匀半空间局部直立异常体为探测目标,建立多个基于温纳高密度电法装置的地电模型,采用有限元等方法进行正反演数值模拟分析,对高密度电阻率法探测分辨率的影响规律进行探讨。分析表明,地形起伏会引起异常体的位置与形态发生畸变和位移,分辨率降低;电阻率差异增大,分辨率提高;深径比增大,分辨率降低;当异常体的水平范围一定时,探测分辨率随纵深的增大而提高。

In recent years,high-density electrical method have been used more and more widely and the researches on resolution influence factors analysis of the high-density electrical method have been drawn much attentions.This paper takes the partially erect anomaly of a uniform half-space as detect target,building different models to simulate and analyze with the Wenner high-density electrical device,employing 2DRES software to process forward and inverse numerical simulation and analysis to obtain the effects of the terrain,resistivity differences,depth to diameter ratio and deepening on the high-density electrical probe resolution.The results show that the undulating terrain makes the apparent resistivity anomaly location displaced,shape distorted and the resolution reduced;the detecting resolution of high-density resistivity method increases with the increase of resistivity difference;the detecting resolution decreases with the increase of depth to diameter ratio,and the detecting resolution increases with the increase of extended depth when the lateral width of certain anomalies reaching a critical level.Finally,the recommendations to improve the detecting resolution are given by combining the theoretical analysis and the engineering application.