Depositional Environment and Sequence Stratigraphy of the Kangan Formation in South Pars Field

The Early Triassic carbonates of Kangan Formation are major gas reservoirs in the Southwest of Iran and the northern Persian Gulf. Facies analyses of Kangan Formation led to recognition of 13 microfacies which are related to tidal flat, lagoon, shoal and open marine environments. Examination of vertical and lateral facies changes and thire comparison with their modernand ancient counterparts, all indicate that Kangan Formation were deposited in a shallow carbonate ramp platform similar to the present day Persian Gulf. The sequence stratigraphic studies showed that the Kangan Formation consists of two third order depositional sequences (in the A and B wells), each consisting of transgressive and highstand systems tracts. The lower boundary of the first sequence is a type 1 unconformity, but other boundaries are type 2 unconformity. Typical reservoir zone in the Kangan Formation is dominated in early highstand systems tract deposits and concentrated in shoal grainstone facies. However, in this paper, typical intervals such as sequence boundaries, maximum flooding surfaces, stacking patterns and system tracts were studied. Keywords: Kangan Formation, Early Triassic, Lithofacies, Microfacies, Sequence Stratigraphy.