Hidrologia isotopica de la influencia de una tormenta en la descarga natural del agua subterranea en la Sierra de Monte Alto

Abstract

One of the principal recharge zones of aquifers beneath Mexico City is the Monte Alto range which forms the west side of the Basin of Mexico. A storm runoff analysis using environmental isotopes and chemical data was effected, including hydrogeological field observations in a small basin near the summit of the range. The basin is underlain by andesitic rocks interbedded with pyroclastics. Results show that infiltration in this zone could be greater than 70% of precipitation. An anomaly in the hydrograph separation suggests three runoff components: capillary fringe water which is more important than we expected; a storm water component; and a component attributed to groundwater. -English summary