부산 북서부 화강암지역 지하수의 화학적 특성 = Geochemical characteristics of groundwater in granite of northwestern area , Pusan

다국어 초록 (Multilingual Abstract)

The purpose of this study is to examine hydrogeochemical characteristics of groundwater for granite in the northwestern area of Pusan city and the potential of groundwater pollution in this area. According to the Piper diagram, groundwater in the study area mostly belongs to Ca^(2+)-HCO₃^- and Na^+-HCO₃^- types. High concentration of Ca^(2+) and Na^+ in groundwater are ascribed to the dissolution of plagioclase. According to the factor analysis, three factors are determined. Factor 1 consists of EC, pH, Na^+, K^+, NH₄^+, Cl^-, SO₄^(2-), and NO₃^-. Factor 2 consists of SiO₂ and HCO₃^-. Factor 3 is composed of Mg^(2+) and SiO₂. Based on the hydrogeochemical modeling. groundwater in the study area is undersaturated with respect to amorphous silica, and is oversaturated with respect to quartz and chalcedony. Based on phase stability diagrams^(1-2)), groundwater in the both areas is mostly in equilibrium with kaolinite and becomes undersaturated with respect to feldspars, evolved from the gibbsite during water-rock interaction.