The Chemical charcteristics of geothermal fluids in Jiaodong Penisula, Shandong, China

Abstract

In order to trace the processes controlling the fluid composition, fluid mixing, fluid origin and reservoir temperatures, major, trace and water isotope analysis were performed for groundwaters (boreholes and springs) in the Shandong area, China. A total of 16 hot springs were sampled, with the geothermal fluid temperatures ranging from 28 to 81°C, pH from 6.95 to 8.44, Cl from 58 to 5316 ppm, SiO2 from 61 to 137 ppm, B from 0.21 to 0.91 ppm, HCO3 from 60 to 573 ppm, δD from -72.0 to - 48.0‰, and δ18O from -9.8 to -6.6‰. Based on geochemical relations, geothermal water in study area are mainly recharged by modern atmospheric precipitation mixed with seawater or shallow groundwater with the hydrology controlled by deep faults with a NNE strike.