Biostratigraphy of Dalichai Formation in Bar and Sarmeran sections (Binalud Mountains) Northeastern of Iran on based ammonite fauna with special emphasis on Phylloceratidae Family

IIn this research, the biostratigraphy of the Dalichai Formation in the Bar and Sarmeran sections at theBinalud Mountains has been studied with special emphasis on the most abundant ammonite family(Phylloceratidae family). The Dalichai Formation is mostly composed of marl, shale, siltstone, nodularmarly limestone and limestone. In this study, by studying 219 specimens taken from the Bar andSarmeran sections, ammonites belonging to 11 species, 4 Genus and 1 subgenus of the Phylloceratidaefamily have been identified. Based on the research completed, it is possible to consider an age equivalentto the Middle to Late Jurassic for the examined sequence of the Dalichai Formation in the Bar andSarmeran sections. Paleobiogeographically, the existing ammonite fauna are closely related to the sub-Mediterranean Province of the northwestern Tethys. The Zigzag Zone of the Early Bathonian and theBimammatum and Planula Zones of the Late Oxfordian have been recognized.