Geothermal exploration in the Nemrut Caldera and surroundings (Eastern Anatolia-Turkey): Trying to unlock of geothermal potential in one of the world's largest calderas

Nemrut Volcano, which surfaces in the north of Bitlis province in Türkiye, is one of the most important active members of the Quaternary volcano sequence in Eastern Anatolia. 

According to historical records, the last volcanic activity in the region was in 1441 in the north of Nemrut Caldera and the basalt flows formed as a result of this volcanic activity caused Nemrut to be one of the last known active stratavolcano volcanoes in Turkey. It is possible to talk about a formation mechanism in which the intense tectonism in Eastern Anatolia is also effective.

Nemrut Caldera, which has a surface area of approximately 36 km², has a total of 5 lake formations, two of which are large, and Lake Nemrut is known as the second largest caldera lake in the world. Water temperatures in the lakes in the caldera vary between 16-41 ⁰C. Hot water and gas outflows are observed in and around the caldera, which makes the region interesting for both geoscientists and geothermal energy investors. Due to the volcanic activity extending towards the north-east, there are hot water springs formed due to volcanism on the shore of Lake Van in the east of the region. 

The potential for geothermal energy applications in the region is still being investigated. In this context, the surface geology of the caldera and its surroundings was analysed and a series of hydrogeochemical investigations were carried out by taking samples from the hot and cold waters in and around the caldera and evaluating some critical elements. According to the results of chemical analyses and isotope analyses, since the hot-cold water mixture is intensely observed in the region, an exploration drilling to be carried out at the correct location in the region is also important in terms of understanding the reservoir levels and conditions.