Biostratigraphy of the Oligocene deposits of Pabdeh Formation based on planktonic foraminifera in Bandar Abbas area

• Main Authors: Jahanbakhash Daneshian, Mahboobeh Sadat Tabatabaei, Alireza Tahmasbi
• Format: Article in Journal/Newspaper
• Language: Persian
• Published: University of Isfahan 2020
• Subjects: pabdeh formation; biozonation; oligocene; planktonic foraminifera; bandar abbas hinterland; Stratigraphy; QE640-699; Planktonic foraminifera
• Online Access: https://doi.org/10.22108/jssr.2020.121426.1152; https://doaj.org/article/27112b4770e74a32be53d509e523a551

Abstract In this research, the biostratigraphy of Oligocene deposits of the Pabdeh Formation in Bandar Abbas region is considered. For this purpose, the planktonic foraminifera was studied and identified. Based on the index forms of these microfossils, biozones were recognized and compared to global biozonation. Investigation of the stratigraphic distribution of these microfossils in the four studied surface and subsurface sections (Champeh, Safid, Band-e Lengeh, and Taftan) led us to the identification of the Eocene/Oligocene boundary and four biozones of planktonic foraminifera (Zone E16, Hantkenina alabamensis Highest-occurrence Zone, Zone O1, Pseudohastigerina naguewichiensis Highest-occurrence Zone, Zone O2, Turborotalia ampliapertura Highest-occurrence Zone, Zone O3, Dentoglobigerina sellii Partial-range Zone) in this region. Based on the foraminiferal assemblages and their biozonation, the age of Oligocene deposits of the Pabdeh Formation is Rupelian. Also, the lateral extension of Oligocene deposits of the Pabdeh Formation in the studied area has been considered. Keywords: Pabdeh Formation, Biozonation, Oligocene, Planktonic foraminifera, Bandar Abbas Hinterland. Introduction Folded Zagros with about 2,000 km long is divided into Lurestan, Dezful Embayment, Izeh Zone, Abadan Plain, Fars, and Bandar Abbas hinterland. ThePabdeh Formation mainly is composed of shales and marls with a marine origin, comprises alternation of dark to light gray shale beds and thin to thick limestones with good preservation of planktonic foraminifera, developed in southwest Lorestan, Khuzestan and Fars Provinces (Aghanabati 2011). James and Wynd (1965) introduced a type section of this formation in Tang-e Pabdeh and Wynd (1965) presented biofacies and biostratigraphic zonations of this formation for the first time. In this research, the Oligocene deposit of Pabdeh Formation has been studied in terms of biostratigraphy and standard biozonation. Material & Methods In order to study of planktonic foraminifera in Bandar Abbas ...