oa Reservoir Rock Characterization, Classification and Pore Typing in the Dalan/Kangan Carbonates (Khuff Analogues), South Pars Field

The South Pars Field, discovered in 1990, is part of the world's largest single gas accumulation located in the Gulf. The Iranian part of this immense gas accumulation accounts for 5% of the world’s and 60% of Iran's total gas reserves. This Field produces from Dalan/Kangan carbonates (Khuff analogues). These Permian–Triassic carbonate reservoirs in the field are highly stratified in nature and display layer-cake geometry. Combined core analysis and detailed thin section studies are used for facies analysis. Accordingly, 14 major facies were recognized in these carbonates. Facies analysis shows that their depositional setting was located along the inner part of an epiric carbonate system that extended from a peritidal setting to a shallow subtidal zone (back-shoal setting), passing over to a high energy shoal and fore-shoal facies (Figure 1).