Geological and Geochemical Characteristics of the Geothermal Resources in Rucheng, China

The development of geothermal energy promotes the changing of energy consumption structure in China. A series of experiments were performed to evaluate the geothermal resources of Rucheng County, which is the largest geothermal field in Central South China. The experiments include geothermal exploration, apparent resistivity, and determining the geochemical characteristics of the geothermal water. The experimental results show that the F3 fault zone and F1 hanging wall secondary fault are the main thermal control, heat conduction, water diversion, and thermal storage structures. The pH, EC, and Eh of the river water, shallow groundwater, and geothermal water exhibit seasonal changes. The pH and EC of the geothermal water are higher than those of the river water and shallow groundwater, while the Eh is lower. In addition, the corrosivity coefficient Kk and the Ryznar index are used to evaluate the corrosivity and calcium carbonate scaling of the geothermal water, and it is found that the geothermal water has no corrosiveness or calcium carbonate scaling, which indicates that the geothermal energy in Rucheng County has wide application prospects.