GEOCHEMISTRY OF LOW-TEMPERATURE GEOTHERMAL FLUIDS AND WELL SCALES

Direct geothermal uses have been reported both in Romania and Iceland. As a result of a research cooperation between the authors from the mentioned institutions, a geochemical assessment of Romanian geothermal field is presented based on analytical data of fluids sampled at the wellhead of low-temperature well. Analyses of the water samples include major and minor elements. According to different diagrams, geothermal waters have been classified. With the aid of speciation programs, the analytical data were used to model individual species activities in the initial aquifer fluids that feed the well. The modelled aquifer fluid compositions were used to assess how closely equilibrium is approached between solution and various minerals. Then the deposits which have been formed by geothermal water utilization were structurally analysed