Influence of faulting on groundwater quality in Valle del Mezquital, Mexico

The hydrogeology and geological structure of the Mezquital basin are proposed as causes influencing groundwater quality. The integration of a geological survey with groundwater analyses and subsurface stratigraphy explains the spatial and temporal trends of groundwater quality. Higher concentrations of nitrates were measured near faults and fractures acting as recharge sites of wastewater into a shallow aquifer. The faults allow the main aquifer to discharge at specific sites. Deep groundwater flow from limestones recharges the main volcanic aquifer.