The Gurpi Formation (Upper Santonian – Upper Maastrichtian, Marun Oil Field) Biostratigraphy and Paleoecology Investigation

The Gurpi Formation, one of the geologycal units of the Zagros Basin, stretches with in the Folded Zagros in the provinces of Khuzestan, Lorestan, and Fars,in southwest Iran. In all 525 samples were collected from five stratigraphic sectiones of the Gurpi Formation in Dezful embayment Zone for studying biostratigraphy. Totally 47 species from 23 Planktonic foraminifera genera were recognized in this study. From a biochronostratigraphic point of view, eight of the identified biozones are typically restricted to the Late Santonian to Late Maastrichtian. To examine the paleoecology of the formation, some important ecological factors including water level, salinity, and oxygen regime changes during the depositional courses of the formation were analysed.