Multilayer Stratification Earth by Kernel Function and Quasi-Newton Method

Obtaining the resistivity of the soil layers and their thicknesses from measurements constitutes an essential stage of grounding systems projects, since these data provide valuable guidance to the engineer. The literature presents methods that may result in inaccurate stratification. In order to implement a robust quasi-Newton algorithm to calculate the parameters of horizontal multilayer soils using measurement data collected with the Wenner array, this article uses first derivatives of the objective function and two approaches: a kernel function with the Prony's method and the other for the apparent resistivity. The method does not use infinite series neither solves improper integrals, and shows accuracy and robustness. Soil stratifications with two, three, four and five layers are obtained from published data in order to validate the proposed method.