Fractal Modeling of Outcrop Fracture Patterns in Alasehir Geothermal Reservoir Turkey

Abstract

Alasehir geothermal area located in Gediz graben is the current high enthalpy geothermal target in Turkey. The geothermal system mainly produces from fractured Paleozoic Menderes metamorphics. In order to characterize the fractured reservoir formations, marble and schist outcrop fracture networks were identified and traced using image analysis software. Primary and secondary fracture histograms were developed and box counting method was used to calculate fractal dimension. It was observed that for both formations fractal dimensions changed between 1.3 and 1.5 similar to those observed for Kizildere and Germencik geothermal fields. Permeability and porosity estimates were obtained using cubic law and a fractal model. It has been observed that permeability and porosity estimates were in accord with those obtained with well test analysis.