Groundwater flow functioning in arid zones with thick volcanic aquifer units: North-Central Mexico

Population increase in arid zones of Mexico has created the presence of 450% new cities with more that 50,000 inhabitants, as related to 1950's. Due to the arid nature of the environment, the once enough spring and shallow water are becoming insufficient for the supply of those cities. An answer leans now in the sustainable development of deep groundwater. The geological features of the country permit the presence of thick fractured volcanic aquifer units with more that 1,500 m in thickness, which have a regional continuous extent of several hundred thousands of square kilometres. Groundwater development decisions need to consider, in the long span, inter-basin groundwater flow and the need to prevent environmental impacts in distant sites hydraulically connected with extraction centres. Radiocarbon is an excellent tool that initially has been applied to characterize groundwater in thick aquifer units in central Mexico to provide with evidence on the hierarchy of flow (local/regional) and water age from where the distance of regional recharge was inferred; obtained flow path length permits to postulate inter-basin groundwater communication; a potential for radiocarbon has been identified for future expansion of research and water management application. (author)