Estimating groundwater mixing ratios and their uncertainties using a statistical multi parameter approach

The method is, in principle, applicable for any number of end members. In this paper, the spatial distribution of the interaction of two layers of the Continental Terminal aquifer (Niger, Africa) was investigated. Mixing between the deep CT2 and the shallow CT3 aquifer occurs where the separating layers are thinning out or due to improper sealing of some boreholes. Radiogenic 4He concentrations, which differ significantly in the two aquifers, were used as independent parameter to crosscheck the mixing calculations.