Fractures Analysis Using Core Data and Image Logs: A Case Study in the Dalan–Kangan Reservoir of South Pars Gas Field, Iran

South Pars Gas Field is the largest gas field in the world. This field in the Persian Gulf and is located on the border of Iran and Qatar. In it, Dalan–Kangan formations are containing gas reservoirs. Evaluation and study of fractures in carbonate reservoirs is essential in the process of production and development of hydrocarbon fields. Core data and imaging logs are the most important tools in achieving this goal.in this study, using core data and image logs, Dalan–Kangan reservoir fractures in terms of distribution and relative orientation were investigated. Based on the results, both natural and closed fractures were present in large quantities in the studied well. In core data, the ratio of closed fractures filled with minerals was higher than other natural fractures. No major faults were observed in the wells studied and only a minor fault with a displacement of several millimetres was observed. The results of the FMI log showed 120 open fractures as well as 20 closed fractures. Open fractures often had a slope of 50 to 80 degrees and the azimuth was N74W and S80E. Their average aperture was 0.27 mm in the K4 section. Also, closed fractures were mostly in the two main directions of azimuth N48E and S84W with a slope of 51 and 63 degrees. The results of this study can be used to discuss field development and fabrication of fracture models as well as facies models.