Integrated Approach For Geothermal Exploration In Salmas Region, N-W Iran

The Northwestern parts of Iran are enriched by many geothermal resources. One of the promising prospects in this area is Salmas geothermal region. According to the geological and geochemical studies in the region, there is a low to medium-deep geothermal reservoir. At the first step geothermal map of the study area had been prepared then the locations of all geothermal surface manifestations were plotted on the map. Field observations show that the fractures and faults play the main role in the circulation of geothermal fluid. Altered areas can be seen in many parts of the region and most of them are related to geothermal activity. Geochemical studies have been carried out on 6 warm springs that emerge in this region whose temperature ranges from 27 to 40 ° C. The warm springs are located in two separate places. One of the spring’s complexes, in the eastern parts of the region, has different temperatures and contains H2S. The other complex is located in the western part which contains CO2. Travertine deposition can be seen around these springs. The characteristics of thermal water have been indicated through analyzing water samples from hot springs. The results of the chemical analysis show that the geothermal fluid is in the range of bicornate waters. There is also evidence of the mixing of geothermal fluid with meteoric water. This geothermal fluid is considered alkaline water. Geothermometers are applied to estimate reservoir temperature, according to the results of geothermometry studies, the minimum temperature considered for Salmas geothermal reservoir is 110 ° C.