Geological and reservoir modelling of coalbed methane in Karadon Region of Zonguldak Basin (Türkiye): A case study

The Zonguldak Basin stands out as Türkiye's primary hub for bituminous coal production alongside a notable coalbed methane content of mined coal seams. In this study, we are proposing for the first time an integrated approach of geological modelling, reservoir characterization, and production forecasting of one coalbed methane block within Zonguldak Basin to understand the potential of this unconventional resource. The study initiated with the development of a 3D geological model data from the Karadon coal mine. Results of several laboratory tests conducted on coal samples such as desorption capacity which is measured as 666.67 scf/ton is integrated into the model. A reservoir model was developed by incorporating gas composition, pressure-volume-temperature (PVT) characteristics, and special core analysis (SCAL) data. A combination of 1,2,3,4 and 5 wells scenarios is proposed to figure out the best production solution adapted to the study area. As a result, a 5-wells configuration also known as the "5 spot wells" layout is selected. Five wells will be in the same well pad but deviated 600 meters distance in target zones. Each well in the pad includes two frac stages at two separated coal and shale interbedded intervals. The final volumetric projection suggests a cumulative gas production estimates around 1.803 billion m3 from 5 wells, which confirms the potential of coalbed methane as an important additional energy resource to Türkiye’s economy.