Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Allemagne → 2018 → Understanding deep groundwater flow systems to contribute to a sustainable use of the water resource in the Mexican Altiplano

RWTH Aachen University (2018)

Understanding deep groundwater flow systems to contribute to a sustainable use of the water resource in the Mexican Altiplano

Krienen, Lisa

Titre : Understanding deep groundwater flow systems to contribute to a sustainable use of the water resource in the Mexican Altiplano

Auteur : Krienen, Lisa

Université de soutenance : RWTH Aachen University

Grade : Doktorin der Naturwissenschaften 2018

Résumé partiel
In the present research, two sedimentary basins in the Mexican Altiplano were investigated regarding their hydrogeological settings and flow processes : the basin of San Luis Potosí (state San Luis Potosí) and the Calera-Benito Juárez basin (state Zacatecas). The study areas are located in central Mexico within the Mesa Central at around 2,000 m asl. Despite the semi-arid climate, both regions have been developed to important agglomeration centres surrounded by agricultural holdings ; consequently, intense groundwater exploitation is a common challenge. Since the last decades, the water demand has been risen, provoking significant drawdowns of the groundwater surface with 0.6 m to 2.5 m per year. New approaches in water management are therefore needed to sustain the water supply. The aim of this research is to contribute to a sustainable use of the groundwater resource by analysing the hydrogeological setting of two aquifer systems and to assess implications on a regional point of view for the Mexican Altiplano. The technical implementation was achieved by the development of numerical flow models, following the hydrogeological model representations, which are important tools for the assessment of strategies in water management. The investigations also comprise the determination of the structural settings and their realisation in 3D models, since the faults within the graben systems present important flow paths for deep thermal groundwater. The two investigated catchment areas comprise an area of around 1,900 km² (San Luis Potosí) and 2,500 km² (Calera-Benito Juárez), respectively. The horizontal groundwater flow takes place in the porous media of the sedimentary filling. In contrast to the Calera-Benito Juárez aquifer system, which comprises one unconfined groundwater body, a low permeable layer of compacted sand divides the San Luis Potosí aquifer system in two separated systems, an unconfined, near-surface (“shallow”) aquifer and a confined to leaky deep aquifer. The basement of the sedimentary basins is built of fractured Tertiary volcanic rocks underlain by low permeable Cretaceous or Mesozoic rocks. The evaluation of geophysical data exposed the buried fault systems within the basins, which coincide with the regional tectonic structures on the Mesa Central. The depth of the sedimentary filling could not be determined in the Calera-Benito Juárez basin, but allow assertions to a depth of 600 m. This result is against expectations, since other sedimentary basins in the Mexican Altiplano, e.g. the San Luis Potosí basin, are maximum 500 m deep.

Présentation

Version intégrale

Page publiée le 12 mars 2020