Natural fractures characterization by integration of FMI logs, well logs and core data: a case study from the Sarvak Formation (Iran)

Abstract Carbonate reservoirs in Iran are the most important and main sources of oil gas production. Hydrocarbon flow rates from carbonate heavily rely on development natural fractures. This study focuses role fractures reservoir quality considering Sarvak (southwest Iran) as second Iran. To identify small-scale around borehole walls, cores description image logs were utilized. Due to high cost coring, lack orientation low core recovery fractured zones indirect methods based conventional well exploited for fracture characterizations. For this purpose, a complete set data including (FMI), well-log-derived porosity permeability together with petrophysical employed. Interpretation allows different types structures such open, vuggy, partly-filled filled fractures, bedding planes stylolites be identified. Comparisons between petrophysical-log image-log interpretations provide useful relationships characteristics. Neutron sonic show direct relationship porosity, while density log displays an inverse correlation porosity. Neutron-density neutron-sonic cross-plots that dominant lithology studied is limestone minor fractions dolomite shale. Total ranges 2 30%, contribution secondary average, below 3%. Relationships fracture-frequency diagrams correlated frequencies open vuggy have flowed associated production tests. Natural characterization systematic integrated can play optimizing field development, resource reservoir. Once calibrated, method also offers potential exploration tool.