Conodont biostratigraphy of the Kesheh and Dizlu sections, and the age range of the Bahram Formation in central Iran

Conodont fauna from the Kesheh and Dizlu sections in the North Isfahan province were investigated. Shallow-water and/or near-shore conodonts, mainly belonging to the icriodid-polygnathid biofacies, dominate the conodont fauna. Due to the depositional setting which is characterised by predominantly shallow-water palaeoenvironments and the lack of some important zonal index taxa (e.g. Palmatolepis species), a precise conodont biostratigraphy is difficult to establish. The Kesheh section covers sediments ranging from the Givetian hermanni Zone to disparilis Zone whereas in the Dizlu section, the ranges of Middle triangularis to Uppermost crepida, the marginifera to Upper trachytera, and the Lower and Middle expansa Zones indicate a Famennian age. The stratigraphic range of the Bahram Formation is discussed, and according to literature and new conodont data presented herein, it is likely that the age of the Bahram Formation in central Iran has a stratigraphical range from the Givetian (hermanni Zone) to the late Famennian (Middle expansa Zone).