Paleoecology of the Kalat Formation's shale units based on Ostracods in the Kopet Dagh Basin - Chahchaheh section (Khorasan Razavi)

The Kalat Formation is one of units in the Kopet Dagh sedimentary basin and so far have been studied by other fossils (case study) (palynomorphs، calcareous nanoplankton and foraminifera). According to the important ostracoda in diagnosis paleoecology and paleoenvironment، in this study، investigated ostracoda in shale units of the Kalat Formation in Chahchaheh section have been studied for the first time. The Kalat Formation is 115 meter thick in this section and lithologically، it is mainly composed of limestone، sandy limestone and shale. In this study، 44 samples collected from shale units and 30 genera are recognized as well as 44 species of ostracoda. According to the recognized ostracoda، we can consider warm and shallow sedimentary environment with low to high oxygen and fluctuation in rate of sedimentation during deposition of shale units.