Hydrogeological investigations in the Nzega area of western Tanzania

Abstract

Multi-disciplinary hydrogeological investigations have been carried out for five years in the Manonga Basin in western Tanzania, to locate underground water for the Golden Pride gold mine. Ground transient electromagnetic profiling has been found to be useful in defining the total thickness of sands in the basin, and thus provides a vector for drill-targeting potentially water-bearing sands of suitable yield. This however is not diagnostic on its own and must be interfaced with other geoscientific data sets and basin knowledge. Digital elevation models and airborne magnetics have also provided structural information. Thickest sands have been located in areas close to existing drainage. We postulate that the best targets for significant sub-surface water are marked by a coincidence of thick mapped sands near existing drainage, and major structures which cross-cut the basin axis.