Résumé
Groundwater is a very scarce resource in northern Chile, and in many cases it is the only water resource available for many communities. Owe to its scarcity in some cases alternatives are necessaries (e.g. desalinization) and obtaining new groundwater extraction permitsis no longer possible. The Pampa del Tamarugal Aquifer(PTA) is the most important groundwater reservoir in the Tarapacá region, hence, a better understanding of the aquifer, in terms of groundwater availability and quality it is essential for a sustainable and wise use of it.Three-dimensional modelling is an excellent tool to visualize and comprehend the extent, thickness and distribution of an aquifer, and any geological unit.No 3D model has been carried out in the PTA so far, only some hydrochemical and isotopic assessments are known. The combination of these types of assessments with 3D models is a new trend in hydrogeology, as this allowsa better comprehension ofan aquifer or basin. Three dimensional modelling is also helpful in creating a better conceptualization of aquifers in the development of numerical flow models. In this study, the three-dimensional modelling of the PTA intent to separate the PTA into two aquifer levels based on their resistivity/salinity.