TDEM and EM31 Methods for Detecting Sterile Bodies in the Phosphatic Bearing of Sidi Chennane (Morocco)

Exploitation of the phosphatic layers in Sidi Chennane deposit (Morocco) collides frequently with problems bound to the existence, in the phosphatic series, of sterile bodies qualified as derangements. Our study shows that these bodies, masked by the Quaternary cover can be mapped using the Time-Domain ElectroMagnetic Soundings (TDEM) and Frequency Electromagnetic Profilings (EM31) methods. It is based on the acquisition and the interpretation of a series of tests carried out above a visible derangement in an old trench of exploitation, on 2500 TDEM soundings and 5000 EM31 measures carried out in a virgin area of the deposit. This communication concerns to the analysis of the results and of the proceeding for a possible large geophysics survey.