Integrated biostratigraphy of the Upper Cretaceous Abderaz Formation of the East Kopet Dagh Basin (NE Iran)

Pages: 
pp. 21-37
Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran
Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran
Department of Geology, Faculty of Science, University of Shahid Beheshti, Tehran, Iran
Departamento de Ciencias de la Tierra (Paleontología) e Instituto de Investigación en Ciencias Ambientales (IUCA), Universidad de Zaragoza, C/ Pedro Cerbuna 12, E-50009 Zaragoza, Spain
Department of Geology, Paleontology and Fossil Fuels, Faculty of Geology and Geography, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria
Abstract: 

Based on planktonic foraminifera, inoceramids and echinoids, we present a detailed biostratigraphic analysis of the Abderaz Formation at the 606 m thick Padeha section, NE Iran. This sequence consists mainly of gray shales and marls with four levels of chalky limestones intercalated. The lower boundary of the Abderaz Formation with the Aitamir Formation is a paraconformity, while the upper boundary with the Abtalkh Formation represents a gradual transition. Fifty four species of planktonic foraminifera from 15 genera were identified, and five zones were recognized, namely: Whiteinella archaeocretacea (Bolli) Partial-Range-Zone; Helvetoglobotruncana helvetica (Sigal) Total-Range-Zone; Marginotruncana schneegansi (Dalbiez) Interval-Range-Zone; Dicarinella concavata (Brotzen) Interval-Range-Zone; and Dicarinella asymetrica (Sigal) Total-Range-Zone. Based on these data, the age of the Abderaz Formation is determined as earliest Turonian to earliest Campanian. Inoceramid bivalves Cremnoceramus walterdorfensis walterdorfensis (Andert) and Cremnoceramus deformis deformis (Meek) were identified in the uppermost Turonian and in the middle part of the early Coniacian, respectively. Echinocorys ex. gr. scutata and Cordiceramus sp. were recorded near the Coniacian/Santonian boundary.

Keywords: 

Upper Cretaceous, Abderaz Formation, Biostratigraphy, Planktonic foraminiferal zonation, Inoceramids, NE Iran

VOLUME 41 (1-3)/December 2012

Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran
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Faculty of Science, Department of Geology, Ferdowsi University of Mashhad, Mashhad, Iran
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Department of Geology, Faculty of Science, University of Shahid Beheshti, Tehran, Iran
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Departamento de Ciencias de la Tierra (Paleontología) e Instituto de Investigación en Ciencias Ambientales (IUCA), Universidad de Zaragoza, C/ Pedro Cerbuna 12, E-50009 Zaragoza, Spain
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Department of Geology, Paleontology and Fossil Fuels, Faculty of Geology and Geography, Sofia University “St. Kliment Ohridski”, Sofia, Bulgaria

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bl. 24, 1113 Sofia, Bulgaria

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 24, 1113 Sofia, Bulgaria
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Department of Geology, Faculty of Mining and Geology, University of Belgrade, Kamenicka 6, P.O. Box 227, 11000 Belgrade, Serbia
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 24, 1113 Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 24, 1113 Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 24, 1113 Sofia, Bulgaria
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Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, Bl. 24, 1113 Sofia, Bulgaria
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Department of Geology, Faculty of Mining and Geology, University of Belgrade, Kamenicka 6, P.O. Box 227, 11000 Belgrade, Serbia

USM 203 du Muséum national d’Histoire naturelle et UMR 7207 du CNRS, 17 rue du Docteur Magnan, 75013 Paris, France
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Department of Geology and Paleontology, University of Mining and Geology “St. Ivan Rilski”, 1700 Sofia, Bulgaria

Faculty of Geology and Geoenvironment, Department of Geography-Climatology, University of Athens, Panepistimioupolis, 15784, Athens, Greece