Drilling applications for geothermal purposes: Kayseri-İncesu-Subaşı (kis-2016) representative geothermal energy exploration drilling case study

Geothermal exploration drilling activities were carried out for geothermal exploration in the geothermal resource exploration area of MTA General Directorate located in the southwest of Erciyes Mountain. Yellibel and Karlığıntepe formations of the Yahyalı Stack, which are composed of schist and crystallized limestones deposited in the Silurian-Upper Cretaceous range and have undergone metamorphism in the green schist facies, are located in the area where the sounding was carried out. The Yahyalı sequence is tectonically overlain by the Aladağ ophiolite nappe. Volcanic and sedimentary rocks are deposited in the Middle Eocene-Quaternary interval. KİS-2016/9 geothermal exploration drilling was completed at a depth of 2.753 m. 9 5/8" closed enclosure pipe was descended between 0-1,393,50 m and cemented behind the pipe in order to prevent low temperature fluid mixing from upper levels and to ensure well safety. In the well, closed and filtered pipes with 6 5/8 diameter have been descended between 1,378,06-2,750 m. Fluid could not be obtained in the well after production. As a result of negative production results, wells were tried to be developed by acidification and perforation operations. In this context, 20 l/sec compressor, 18 l/sec artesianic discharge and 45.2 °C production temperature were obtained in geothermal drilling of KİS-2016/9 by perforating acid levels of 1.075-1.110 m. In order to reveal the classification of the waters, the process of the waters until they reach the surface, the water-rock interaction, the mixing ratio, the hydrochemical facies and the hydrochemical history of the field, thermal water sample was taken from the well during the production and the analysis of the sample was performed in the laboratories of MTA General Directorate. According to the International Association of Hydrogeologists (IAH) classification, water produced in KİS-2016/9 geothermal drilling is classified as with sodium, chlorinated, boron, iron, arsenic, thermal-mineralized groundwater.