The studied area is located in Southern Khorassan province at margin of Lut platform. Kaboudeh and North Ark stratigraphic sections were measured and sampled in order to describe sedimentary facies and determine the depositional environments. Carbonate facies, terrigenous facies and mixed terrigenous-carbonate facies were recognized as three main sedimentary facies sets in both sections. Seven microfacies types were distinguished for Kabudeh section which are occurred in lithoral sand bar, lagoon, coral-coralin algal-nummulitic patch reefs and proximal foreslope sub-environments and Six microfacies types were recognized for North Arc section in lithoral sand bar, lagoon, reworking sand bar, nunmulitic patch reefs and proximal foreslope sub-environmets; ranging from lithoral to proximal part of outer ramp settings. On the basis of the index species larger benthic foraminifera as follows: Nummulites atacicus, Assilina leymereie and foraminiferal assemblages: Alveolina desipiens, Alveolina cf. ellipsoidalis, Opertorbitolites douvillie, Orbitolites minimous, Nummulites globulus, Luckartia haimei, Early Eocene (Yprisian) is suggested for the studied deposits. Absence real coral reefs and replacement larger benthic foraminifera are considered as the effects of Paleocene-Eocene boundary global changes in the studied area
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