Document Type : Original Research Paper


Assistant Professor, Department of Geology, Faculty of Science, Payame Noor University (PNU), Tehran, Iran


In this research the biostratigraphy and lithostratigraphy of the Talou section (northwest Damghan) have been studied based on brachiopods of Lower Carboniferous in Mobarak Formation. The 580 me thick Mobarak Formation in Talou section consists of dark gray limestone with intercalation of organic rich black shale. This formation in the studied area is conformably overlie on Jeirud Formation. Vermiculate limestone of Elika Formation overlies the Mobarak Formation with an erosional surface. In the studied interval 25 genera and 30 species of brachiopods were identified. 4 assemblage zones have been identified in the early Carboniferous.
Biozone 1 (Early Tournaisian): this zone is characterized by the following indicator species community. Spinocarinifera nigra, Rugosochonetes cf. hardrensis (Phillips,1841), Rossirhynchus adamantinus, Shumardella sp., Cleiothyridina transversa., Rossirhynchusadamantinus, Shumardella sp.; Biozone 2 (Middle Tournaisian): Spirifermissouriensis, Spirifer attenuatus (Sowerby,1839), Spirifer cf. trigonalis (Martin, 1809), Athyrishibernica Syringothyriscospidata; Biozone 3 (Late Tournaisian): Tomiproductus elegantulus, Marginatia aff. burlingtonensis (Hall,1893), Leptagonia cf. regularis, Fusellatornacensis, Marginatiaburlingtonensis; Biozone of 4 (Early- Middle Visean): Buxtonia cf. praejuresanensis, Marginatia cf. kinghirica, Cleiothyridina cf. okensis (Grunt,1980). therefore, the age of Mobarak Formation in the Talou section, is Tournaisian to Middle Visean. The sedimentary environment of Brachiopods of the Mobarak Formation are lagoon, bar or reef and fore-reef.


Main Subjects

Alavi, M., and Salehi-Rad, R., 1975- Geological map of Damgan (Scale1/100000). Geological Survey of Iran, Sheet no.6862.
Assereto, R. 1963- The palaeozoic formation in central Alborz (Iran) (preliminary note). Rivista Italiana di palaeontologia e stratigrafia 69: 503-543.
Assereto, R., 1966-Geological map of upper Djajerud and Lar Valleys (central Alborz, Iran), scale 1/50000,with explanatory note. Institute of Geology, University of Milano, serie G, publication 232, 1-86.
Bahrammanesh, M., 2008- Brachiopods from the Early Carboniferous of North Iran: Classification, Biostratigraphy and Paleobiogeography. Universital degli Studi di Milano. pp. 160. Ph. D. Thesis.
Bahrammanesh, M., Angiolini, L., Antonelli, A. A., Aghababalou, B. , and Gaetani, M., 2011-Tournaisian (Mississippian) brachiopods from the Mobarak Formation, North Iran, Geo Arabia, Vol: 16, no. 3, P. 129-192.  doi: org/10.26879/758.
Boucot, A. J., 1975-Evolution and Extinction Rate Controls. Developments in Palaeontology and Stratigraphy, Volume 1. xv + 427 pp., 42 figs, 6 tables, 3 pls. Elsevier Scientific Publishing Co., Amsterdam, Oxford, New York.
Fantini Sestini, 1966- The Geology of upper Djajerud and Lar valleys.II.palaeontology. Brachiopods from Geirud Formation, Member D (Lower Permian).Rivista Italiana di palaeontologia e stratigrafia 72-1: 9 -50.
Gaetani, M., 1964- Rossirhynchus adamantinus gen. n., sp. n. from the Tournaisian of Central Elburz, Iran (Rhynchonellida). Rivista Italiana di Paleontologia e Stratigrafia, Milano, v. 70, no. 4, p. 637-648.
Gaetani, M., 1965-The geology of the upper Djadjerud and Lar valleys (north Iran), II. Rivista Italiana di palaeontologia e Stratigrafia 71-3: 679-770.
Gaetani, M., 1968- The geology of the Upper Djadjerud and Lar valleys II. Pal., Lower Carboniferous brachiopods from Central Alborz, Iran. Riv., Ital., pal., 74: p. 665-744.
Gaetani, M., Angiolini, L., Ueon, K., Nicora, A., Stephenson, M., Sciunnach, D., Petroi, R., Price, G., and Saburi, J., 2009- Pensylvanian Early Triassic Stratigraphy in the Alborz mountains. Geol. Soc., London. Sp. Pub., 312:p. 79-128.
Jenny, J., 1977- Geologie de stratigraphic de la Elborz oriental entre Aliabad et Shahrud, Iran. Ph.D. thesis, Univ., de Geneva. Geneve. 230p.
Langa, L., and Puura, I., 2008- Systematic position, distribution, and shell structure of the Devonian linguloid brachiopod Bicarinatina bicarinata (Kutorga, 1837); pp. 63–70. 10.3176/earth.2009.1.06.
Legrand –Blain, M., Delvolvé, J. J., and  Perret, M. F., 1984- Les brachiopodes Carboniféres des Pyréneés centrales françaises. 2: Étude desorthida et des spiriferida; Biostratigraphie, Paléoécologie, Paléobiogéographie. Geobios. 17: p. 297-325.
Poletaev, I., and  Lazarev, S. S., 1995- general stratigraphic scale and Brachiopod Evolution in the late Devonian and Carboniferous Subequatorial belt. Bull., Soc., Bel., Geol., 103:p. 99-107.
Waterhouse, J.B., 1982- New Carboniferous brachiopod genera from Huai Bun Nak, North-east Thailand. Paläontologische Zeitschrift 56 (1-2) 39-52.
Wolniewicz, P., 2009-Late Famennian stromatoporoids from Dębnik Anticline, southern Poland. Acta Palaeontologica Polonica 54 (2): 337–350. 10.4202/app.2007.0096.