Hydrogeology and geomorphology of the Calar del Espino (Betic Cordillera, Southern Spain), A highly interesting scientific and experimental karstic system

Abstract

Sierra de Segura is an extensive mountain range, about 3000km2 in area, with 800-1200mm/year of precipitation and groundwater resources assessed as 236 hm3/year. Calar del Espino forms a small and representative hydrogeological unit that discharges almost all groundwater flow through the El Tejo spring. Carbonate rocks nearly 500m thick are exposed over 6 km2 in the core of a synclinal structure and constitute a hanging aquifer. The summit of Calar del Espino (1600-1700m asl) is a karstic plateau corresponding to a remnant of the Segura post-Miocene paleosurface. Hydrograph analysis and physical and chemical characteristics of the water lead to the conclusion that the El Tejo karstic system shows a heterogeneous degree of karstification, little variability in the physical and chemical characteristics of the water, high dynamic reserves, and a long water residence time.