L Bakhshandeh1; KH Khosro Tehrani; T Mohtat; S.H Vaziri; F Keshani
Abstract
The Gurpi Formation is located in the Zagros basin, SW Iran . This Formation in the Banroushan section, SW Ilam,consists of 225 m shale with interbeds of marl that has two formal Members including Seymareh (Lopha) and Emam Hassan . These Members are made up of limestone. The lower and upper boundaries ...
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The Gurpi Formation is located in the Zagros basin, SW Iran . This Formation in the Banroushan section, SW Ilam,consists of 225 m shale with interbeds of marl that has two formal Members including Seymareh (Lopha) and Emam Hassan . These Members are made up of limestone. The lower and upper boundaries of this Formation are continuos with the Ilam and Pabdeh Formations. In the present investigation, 46 planktonic species of 13 genera have been identified. The Gurpi Formation is divided into 10 biozone on the basis of planktonic foraminifera which are cosmopolitan and consist of :biozone1-Globotruncanita elevata Partial Range Zone; Biozone2- Globotruncana ventricosa Interval Zone; Biozone3- Globotruncanita calcarata Interval Zone; Biozone4- Globotruncanella havanensis Partial Range Zone; Biozone5- Globotruncana aegyptiaca Interval Zone; Biozone6- Gansserina gansseri Interval Zone; Biozone7-Contusotruncana contusa Interval Zone; Biozone8- Abathomphalus mayaroensis Interval Zone; Biozone9-Parasubbotina pseudobulloides Interval Zone; Biozone 10- Globanomalina pseudomenardii Interval Zone Based on planktonic foraminifera the Gurpi Formation in the study area was deposited during the Early Campanian to Paleocene times.
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.
L. Bakhshandeh; A. Aghanabati; F. Keshani; T. Mohtat
Abstract
To revise the Abderaz Formation in Koppeh-Dagh basin, its type section was studied considering stratigraphical properties. The main lithology of Abderaz Formation includes gray to blue shale with a thickness of 286.86 meters. This Formation has an attitude of N 45˚ W and 80˚ ...
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To revise the Abderaz Formation in Koppeh-Dagh basin, its type section was studied considering stratigraphical properties. The main lithology of Abderaz Formation includes gray to blue shale with a thickness of 286.86 meters. This Formation has an attitude of N 45˚ W and 80˚ SW. Its lower boundary with Aitamir Formation is unconformable and upper boundary with Abtalkh Formation conformable.
In this study, 58 planktonic species of 26 genuses were identified and presented. The age of Abderaz Formation, based on the identified planktonic foraminifera, was determined from Early Turonian to Early Campanian. Planktonic foraminifera fossils found in Abderaz Formation are more abundant than benthic foraminifera ones that show deep sea and continental slope environment.
Regarding the foraminifera content of the Abderaz Formation, 7 biozones were determined in the Mozduran section (Kopeh-Dagh) which shows Early Turonian – Early Campanian age for Abderaz Formation.
