Contribution of geophysics for the characterization of ore deposits, case of the Bouarfa mine, Morocco.

Laboratory of Applied Geophysics, Geotechnics, Engineering Geology and Environment, Mohammadia School of Engineers, Mohammed V University, Rabat, Morocco

Abstract

Geophysical methods are one of the best ways to determine the potential of a mining area. Indeed, for the prospection of metalliferous deposits, the magnetic method remains essential as it makes it possible to characterize the extent and the depth of the anomalous bodies present in the prospected zone, mainly due to their reaction with the values of the total magnetic field. Thus, for the manganese mining zone of Bouarfa and more exactly Hammraouet, the genesis of the deposit is such that the manganese is generally associated with ferruginous minerals and clearly affect the total magnetic field. That said, the raw results obtained must imperatively be subjected to corrections to only keep the effect of the anomalous bodies on the magnetic field. Hence, we must proceed with the correction of the daytime effect then we eliminate the regional effects to get the map of the residual anomaly and finally we perform a reduction to the pole that will allow us to have well individualized and unipolar anomalies and thus allowing us to locate precisely the potentially mineralized axes. The synthesis of the various maps obtained by spatial interpolation of the data recorded in situ and corrected allows us to locate areas of mining interest and to determine the different tectonic phenomena that took place in our study area. In time, these maps will serve us to guide the subsequent mechanical surveys to confirm the results obtained by geophysical methods.