Preliminary Study on Hydrogeochemical Characteristics of Yanqing Geothermal Field, Beijing

Abstract

Geothermal resource is a sort of renewable clean energy. The development and utilization of geothermal resource in Beijing plain for nearly 50 years. Yanqing basin, a stable production low temperature geothermal field, is located in the northwest of Beijing, 80 km from the center. This paper discusses the hydrochemical characteristics of Yanqing geothermal field by study of the data of geothermal wells in this area. The research shows that the hydrochemical types of geothermal water are HCO3-Na and HCO3-Na·Ca. The Na-K-Mg ternary diagram indicates that the water - rock reaction has not reached equilibrium and the equilibrium temperature of the reaction is low, or that the geothermal water samples has the possibility of receiving precipitation recharge and cold water mixing. The reservoir temperature is estimated by using SiO2 and cation geothermometer.