ABSTRACT
The high-density DC sounding method is a cheap and easy deployed geophysical method for the shallow subsurface prospecting. It is an automatic method controlled by the Personal Computer (PC) using the principle of DC sounding in the arbitrarily inhomogeneous medium. The geophysical equipment and software have developed fully since middle 1990 (OYO 1995, PASI 2010, Loke 2012). The key to the data interpretation is based on the inversion of DC sounding method about the 2D profile and 3D space resistivity image. The usual inversions of the DC sounding method have the least squares method (Loke 2012), conjugate gradient method (Jie Zhang et al 1995, Spitzer 1995) and an iterative algorithm of Approximate Inverse Mapping (AIM) (Yaoguo Li et al 1994) for 3D resistivity data of DC sounding. All these methods involve the sensitive derivation. So, the DC sounding principle and inversion processing of the resistivity image will be further discussed in detail.
