Estimating depth of investigation in dc resistivity and IP surveys

• DOI: 10.1190/1.1444545
• Publication Date: 2002-10-11T15:23:40Z
• Authors: Douglas W. Oldenburg; Yaoguo Li
• Keywords: Induced polarization

In this paper, the term “depth of investigation” refers generically to depth below which surface data are insensitive value physical property earth. Estimates for dc resistivity and induced polarization (IP) surveys essential when interpreting models obtained from any inversion because structure beneath that should not be interpreted geologically. We advocate carrying out a limited exploration model space generate few have minimum differ substantially final used interpretation. Visual assessment these often provides answers about existence deeper structures. Differences between can quantified into investigation (DOI) index displayed with An explicit algorithm evaluating DOI is presented. The curves somewhat dependent upon parameters different models, but results robust enough provide user first‐order estimate region earth no longer constrained by data. This prevents overinterpretation results. analysis reaffirms generally accepted conclusions electrode array geometries depths penetration. However, differences inverted arrays far less than in pseudosection images. Field Century deposit presented their index.