Kh. Khosrotehrani; D. Baghbani; F. Keshani; M. Omrani
Abstract
In order to study Biostratigraphy of Cenomanian – Late Campanian deposits (upper part of Sarvak Fm.,Ilam Fm. and lower part of Gurpi Fm.), kuhe Assaluyeh stratigraphic section selected. Sediments of this interval consist of limestone, argillaceous limestone and marl with thickness of 162 m. In ...
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In order to study Biostratigraphy of Cenomanian – Late Campanian deposits (upper part of Sarvak Fm.,Ilam Fm. and lower part of Gurpi Fm.), kuhe Assaluyeh stratigraphic section selected. Sediments of this interval consist of limestone, argillaceous limestone and marl with thickness of 162 m. In this section Ilam Fm. in age of Santonian overlies Sarvak Fm. disconformably and is underlain by Gurpi Fm. conformably. By micropaleontological study on 55 thin sections, 5 genus and 9 species of planktonic and 16 genus and 13 species of benthic foraminifers were identified. Among distinguished foraminifers, Rotaliidae family forms were studied carefully and revised. It should be mentioned that, 5 genus and 6 species of benthic foraminifers (Rotaliid forms) were recognized in Iran for the first time (in Assaluyeh section) which consist of: Rotorbinella mesogeensis,Rotorbinella campaniola,Iberorotalia reicheli,Calcarinella schaubi, Pararotalia tuberculifera and Pyrenerotalia longifolia. Santonian age was determined for Ilam Fm. by identified foraminifers. In studied section, stratigraphy development of benthic foraminifers was compared by Martinez Biozones Martinez (2007). This biozones were presented on the base of Rotaliid forms for Pyrenees area in Spain. By this comparison, four biostratigraphy zones for upper part of Sarvak and Ilam Fm. are suggested.
saeedeh senemari; L. Fazli; M. Omrani
Abstract
Nannofossils and foraminifera planktonic have been short range stratigraphy and spread vast geographical because of that two fossils groups can be used for subdividing biostratigraphy. According to this, and due to the lack of any correlational paleontological study, the nannofossils of Gurpi Formation ...
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Nannofossils and foraminifera planktonic have been short range stratigraphy and spread vast geographical because of that two fossils groups can be used for subdividing biostratigraphy. According to this, and due to the lack of any correlational paleontological study, the nannofossils of Gurpi Formation have been investigated in north of Gachsaran. This formation has been formed of marl. As a result of this study and based on the obtained nannofossils and foraminifera planktonic, the studied section is Late Santonian to Late Maastrichtian in age, that corresponding to CC16-CC26 Zones (Sissingh, 1977) and Dicarinella asymetrica- Globotruncanita elevata Zone toAbathomphalus mayaroensis Zone (James & wind, 1985).