Depth of Investigation of Dipole-dipole, Noncolinear and Focused Geoelectric Arrays

Szalai, Sándor and Novák, Attila and Szarka, László Csaba (2007) Depth of Investigation of Dipole-dipole, Noncolinear and Focused Geoelectric Arrays. In: 13th European Meeting of Environmental and Engineering Geophysics, 2007. szeptember 3-5., Istanbul, Törökország.

Preview

PDF 1081958.pdf Download (457kB)

Abstract

Investigation depth of various DC geoelectric arrays has always been in the focus of interest of geoelectricians. According to its classical definition (Roy and Apparao 1971), the depth of investigation is the depth of the maximum response due to a horizontal thin-sheet embedded in a half-space, by using a given geoelectric array. On basis of the graph of the thin-sheet response as a function of the depth (from the so-called „depth of investigation characteristics” or DIC function) Edwards (1977) found more realistic to compute the medium depth than the depth of the maximum response. DIC functions have been known so far only for simple colinear arrays, the dipole equatorial array and two focused arrays. Here we provide a summary about the depth of investigation values of various dipole-dipole arrays (for parallel, perpendicular, radial, azimuthal ones), and for the most important noncolinear and focused arrays. Depth of investigation values are computed from both approaches. DIC functions (obtained by a new analytical formula) are also presented, as illustrations. The analytical formula can be used to compute DIC function of any surface geoelectric array. A systematic interpretation of the resulting depth of investigation values provides simple but useful thumb-rules for practical applications.

Actions (login required)

Edit Item