Facies Interpretation and Depositional Environment of central Tethyan Upper Permian, South-West of Iran

In order to progress in the knowledge of Upper Permian evolution of the central Tethys realm, an integrated approach which includes new sedimentological described in central Iran (Shahreza area). Less than 1 kilometer of Upper Permian (Hambast Formation) to Lower Triassic limestones are exposed in the Morghab Mountain, north Shahreza, central Iran. The Upper most Hambast Formation of the Sanandag – Sirjan zone (south Isfahan) has been comprised of thin pink layers of rocks with little interlayers of shale which can be observed index Ammonites of Dorashamian (Paratirolites), even in its last beds. In this study, four paleoenvironmental belts have recognized on the basis of their depositional textures, petrographic analysis and fauna: tidal flat, lagoon, barrier and open marine. The Upper Permian Hambast Formation depicts sedimentation on a carbonate ramp. In the inner ramp, the most abundant lithofacies are medium grained wackestone-packstone with ostracoda, bivalve, echinoid and foraminifera. The middle ramp is represented by packstone-grainstone with foraminifera, algae and echinid. The outer ramp is dominated by argillaceous wackestone characterized by gasteropoda, ostracoda and foraminifera

Keywords:

Hambast Formation , Microfacies , Ramp , Upper Permian , Iran