Investigation technology and approaches for the deep groundwater geochemistry

The development of equipment for sampling and the evaluation of existing technology of in-situ physicochemical parameter for the geochemical investigation of deep groundwater carried out to understand the realistic geochemistry of deep geological environment at Tono area, Japan. The chemical and isotopic composition of deep groundwater to approx. 840m depth has been determined using existing and established techniques. The redox condition of groundwater in the deep granite at approx. 180m depth are monitored using developed equipment. The analysis of water-rock interaction in relation to hydrology, geological structure and mineral saturation indeces, and the analysis of chemical composition using mass balance are available to understand the groundwater evolution. (author)