Geochemical characteristics and spatial distribution of spring water at Jinfo Mountain, Chongqing

Abstract：Spring waters of twenty-two springs at Jinfo Mountain, Chongqing, were sampled and their geochemical characteristics were studied in detail during July and September 2006. Field and laboratory measurements of the concentrations of major cations and anions and other physico-geochemical parameters in the spring waters show that the hydrochemical types of these springs are Ca-HCO3 and Ca and Mg-HCO3, and on that basis, combined with the geological and geomorphological characteristics of the springs, six spring groups may be identified and the significance of the spatial distribution of these spring groups are discussed. The authors calculated the saturation indexes of calcite, dolomite and gypsum in the springs, which can indicate the influences of the lithology of the strata, topography and residence time of groundwater on the water quality. The results show that the spring waters in the area mainly come from penetration of meteoric water, without mixture of groundwater from the deep aquifer. The geochemical characteristics and spatial distribution of the spring waters may well reflect the geology of the study area. This study may provide baseline data for the investigation of groundwater resources and protection of the environment in the Jinfo Mountain area.