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Lower Paleogene shallow marine carbonate rocks are exposed nearby the Shusf city in the Nehbandan area, East Central Iran. The sedimentary succession consists of siliciclastic rocks, siliciclastic-carbonate rocks, evaporitic rocks and carbonate rocks. The stratigraphic analysis of nearby the Shusf city allows to identify four informal rock units namely Palang, Chahchocho, Zibro and Debil formations in the study area. Likewise this paper introduces a detailed study of benthic foraminifera and four local assemblage zones from Selandian to Early Ilerdian age were established for the first time. These assemblages are correctable with the benthic foraminiferal assemblages from Adriatic area (Slovenia), Pyrenees (Spain) and Egypt. The wackestone facies contains the small and large porcelaneous foraminifera which accompany with small hyaline foraminifera, depositing approximately in the same depth in the inner ramp. The grainstone facies consists of hyaline foraminifera, which deposited in middle ramp. The distinctive characteristics of the middle ramp are thinning and flattening of the larger foraminifera shells. Ten microfacies types were recognized corresponding to ramp environment in three depositional settings (littoral, lagoon and barrier) based on sedimentological characteristics and foraminiferal assemblages. The identified microfacies are: evaporitic facies, siliciclastic facies, siliciclastic-carbonate facies, miliolid-pellet wackestone, Valvulina-miliolid wackestone, Alveolina-miliolid wackestone, green algal-Nummulites packstone, hyaline-porcellaneous foraminifera grainstone, hyaline foraminifera sandy limestone and hyaline foraminifera grainstone.