Geothermal Resource Assessment in Derik Region (NW-Iran)

Abstract

Derik geothermal region has area of 242 km²and is located 10 km to the west of Salmas city in west Azarbaijan province of Iran. The most outstanding surface manifestations of geothermal energy in this region are three warm springs and outcrops of travertine deposits and quaternary basalt outcrops around warm springs. Temperature range of warm springs varies from 31 to 32.6 °C. We visited and sampled warm springs of the Derik region, then chemical analysis and geochemical studies were conducted. Based on silica geothermometers, estimated temperature range of Derik geothermal reservoir is 53 to 90 °C. Due to the presence of extensive outcrops of travertine deposits in the region, it is believed that probably geothermal reservoir host rock is a carbonate lithological unit. Based on data from a shallow borehole in the region it is found that thermal gradient of the region is about 50 °C/Km, so, probably geothermal reservoir is located in 1000 to 1800 meters depth regarding geothermometry results. According to volumetric method stored thermal energy in the geothermal reservoir is approximately 7.67 × 10⁷kj.