Utilization of reservoir characterization and hydraulic fracturing for reservoir sti̇mulation modeling of enhanced geothermal systems (EGS)

This thesis presents the characterization of the crack mechanisms in marble formations, which are likely to be potential reservoir rocks, in the exploration drilling located in a field with high geothermal potential in the south of the Menderes Graben. It covers the characterization of these reservoirs by deep borehole drilling and extensive field studies, creating an artificial enhanced geothermal system using the hydraulic fracturing method, and developing these fracture propagations with numerical modeling. The fracture-strain orientations will be obtained in the field by the exploration tests conducted in the borehole and field characterization studies. Furthermore, the principal stress and crack orientations that control the propagation of fracture-crack occurring in the reservoir rock will be determined in detail and controlled. Then, the principal stress and crack orientations in the reservoir rock will be determined in detail. In-situ stresses and their orientations, which determine the crack mechanisms and characteristics in the potential reservoir rock determined with the help of the input parameters obtained from these studies, will form the basis of hydraulic fracturing studies. In this way, it will be possible to numerically model the fracture network development in the rock using the hydraulic cracking method. As a result of these studies, an enhanced geothermal system developed with an artificial reservoir with optimum fluid and heat transfer properties will be implemented by controlled stimulation of the crack mechanism in the reservoir rock. In this process, Mfast software educationally supplied by Baker Hughes company will be used for hydraulic fracturing modeling.