3D inversion of DC/IP data using adaptive OcTree meshes
Eldad Haber, Justin Granek, D. Marchant, Elliot Holtham, Douglas W. Oldenburg, Roman Shekhtman · 2012
Data acquired from a direct current (DC) and induced polarization (IP) survey can be used to recover the conductivity and chargeability structures of the subsurface of the earth. In order to maximize the value of such a survey, the data should be inverted in 3D. As surveys get larger and targets get more complex, the discretization applied in regular rectilinear meshes can become cumbersome, resulting in prohibitively large numbers of cells. This problem is exacerbated in the presence of severe topography, or in cases of irregular survey geometry. Applying an adaptive OcTree mesh structure, it is possible to obtain fine resolution cells in regions of high variability without adding unnecessarily small cells where they are not required. This results in a vastly decreased number of cells, without penalizing the potential for high resolution recovered models. We develop the DC/IP inverse algorithm on the Oc-Tree mesh, and apply it to a field example from South America.