Chemistry of geothermal fluids in Dienbien and Sonla provinces, NW-Vietnam,

Abstract

North-west Vietnam is a very special area where development of geothermal energy will be significant for socio-economic activities. The data in this project is taken from a previous research in 2004. Thirty-four samples are taken from 119 hot springs for further study, with the purpose of estimating and interpreting the chemical compositions of the water, by using the methods as triangle diagrams, geothermometers, evidence of mixing and log Q/K plot. The 34 samples were divided into 5 groups based on the location and structure of geology. The study results show that Group 1 with samples S1, S2, and S3 give a good estimation of the temperature of the reservoir from 73°C to 150°C with small deviation between methods. Group 2 with samples S8, S18, and S19 give a temperature from 76°C to 111°C. In Group 3 with samples S11 and S12, reservoir temperature is from 59°C to 110°C. Group 4 with S72 and S73 samples, the temperature of reservoir drops between 60-100°C. Group 5 with samples S6, S65, S75, S77, and S78 the reservoir temperatures estimated by silica geothermometers are quite low and they might be from a different reservoir.