Stratigraphy and Palaeontology
Zeinab Manouchehri; Tayebeh Mohtat; Seyed Ali Aghanabati; Morteza Khalatbari Jafari; Fatemeh Vakil Baghmisheh
Abstract
The sediments are generally limestone and marl. The lower boundary with the loer red Formation is disconfomity and the upper boundary with the equivalent formatin of Bakhtiari Firmation is paraconformity. The total number of fossils found in this section is 69 species, 72 genera and 46 families. These ...
Read More
The sediments are generally limestone and marl. The lower boundary with the loer red Formation is disconfomity and the upper boundary with the equivalent formatin of Bakhtiari Firmation is paraconformity. The total number of fossils found in this section is 69 species, 72 genera and 46 families. These sediments are formed in an open shelf and under the open sea and lagon environment. The variety and abundance of bentic foraminifer’s forms and the low presence of plagic forms testify to the shallow basin in this section, which is also confirmed by the study of other fossils. One of the Markable features of this section is the presence of Ammonia species, especially Ammonia parkinsonia. This section has a complete sequence of members of Qom Formation. This species are profe of shallow water and continental shelf for this carbonates. This section consist all of members of Qom Formation and based on identified foraminifera comparable to assemblage zone 1 & 2 introduced by Adams & Bourgeois (1967). These zones that inclod: 1-Borealis Melo Group- Meandropsin; 2- Miogypsinoides- Archaias- Valvulinid. Based on index foraminifer's species and their stratigraphic distribution the age of this section is Chatian- Burdigalian (Upper Oligocene-Lower Miocene)
Stratigraphy and Palaeontology
Arash shabanpour Haghighie; Lida Bakhshandeh; Tayebeh Mohtat; Masood Zamanipedram; Seyed hamid Vaziri
Abstract
In this research the Gurpi Formation in the Zagros Basin outcropping in the Dasht-e Arjan section, Shiraz province ,for the purpose of biozonational and Paleobathymetric studies were investigated. The thickness of these sediments is about 130 m and consists of Limestones and Shales.To determine the palaeobathymetry ...
Read More
In this research the Gurpi Formation in the Zagros Basin outcropping in the Dasht-e Arjan section, Shiraz province ,for the purpose of biozonational and Paleobathymetric studies were investigated. The thickness of these sediments is about 130 m and consists of Limestones and Shales.To determine the palaeobathymetry of the Gurpi Formation, Planktonic and benthic foraminifera were investigated . A depth of about 270m to 510m was determined for these sediments based on the ratio of planktonic foraminifera to the total assemblages of foraminifera after omitting infaunal benthic foraminifera (%P*) by using the equation D = e (3.58718+(0.03534 × %P* )).In this study sixty-two species of planktonic foraminifera belonging to eighteen genera were recognised .According to the studied planktonic foraminifera the Upper Cretaceous deposits in this area were divided into nine biozones as following :biozone1- Dicarinella concavata Interval Zone. Biozone2- Dicarinella asymetrica Total Range Zone. Biozone3- Globotruncanita elevata Partial range zone .Biozone4- Globotruncana ventricosa Interval Zone. Biozone5- Radotruncana calcarata Interval zone. Biozone 6- Globotruncanella havanensis Partial Range Zone. Biozone7- Globotruncana aegyptiaca Interval Zone. Biozone 8- Gansserina gansseri Interval Zone. Biozone 9- Contusotruncana contusa Interval ZoneBased on the studied planktonic foraminifera the Early Santonian to Maastrichtian ages were determined for the sediments .
Stratigraphy and Palaeontology
A. Shaabanpour Haghighi; , L. Bakhshandeh; T. Mohtat; , M. Zamani Pedram; S. H. Vaziri
Abstract
In this study the Upper Cretaceous sediments in the Zagrous Basins Fars province,the Pyrgheib Section,for the purpose of Biostratighraphy and sea level change studies were investigated. These sediments with about 206 m thickness consist of Limestone, Shale, Marl and limy marl. The investigated ...
Read More
In this study the Upper Cretaceous sediments in the Zagrous Basins Fars province,the Pyrgheib Section,for the purpose of Biostratighraphy and sea level change studies were investigated. These sediments with about 206 m thickness consist of Limestone, Shale, Marl and limy marl. The investigated foraminifera led to identification of 70 species of planktonic foraminifera that belong to 16genera. Based on planktonic foraminifera the Upper Cretaceous deposits were divided into 6 biozone which are cosmopolitan and respectively are:biozone1 - Dicarinella concavata Interval Zone,Biozone2- Dicarinella asymetrica Total Range Zone,Biozone3- Globotruncanita elevata Partial range zone Biozone4- Globotruncana ventricosa Interval Zone,Biozone5- Radotruncana calcarata Interval zone. Biozone6- Globotruncanella havanensis Partial range zone ,Biozone7- Globotruncana aegyptiaca Interval zone. Biozone8- Gansserina gansseri Interval zone, Biozone9- Contusotruncana contusa Interval Zone. The Upper Cretaceous sediments in the study area on the basis of Planktonic Foraminifera are of the Late middle Coniacian to theLate Maastrichtian ages. According to the Morphotype groups of planktonic foraminifera deeping the basin from the Coniacian to the Middle Santonian is seen .However, in the late Santonian shallowing the basin and again in the Early Campanian deeping the basin, in the Late Campanian and close to the Campanian-Maastrichtian boundary shallowing the basin and a sea regression is observed.
Stratigraphy and Palaeontology
Fateme Mahdikhani; Mahmoud Reza Majidifard; T. Mohtat; L. Bakhshande; M. Zamanipedram
Abstract
In order to study the biostratigraphy and lithostratigraphy of the K/Pg boundary two sections was considered. They are the Kuh-e Zaluband and Kuh-e Hunu sections in east of Khur (Esfehan Province). At the Kuh-e Zaluband section has a maximum thickness of 100 m, consisting of marl, limestone, sandy limestone, ...
Read More
In order to study the biostratigraphy and lithostratigraphy of the K/Pg boundary two sections was considered. They are the Kuh-e Zaluband and Kuh-e Hunu sections in east of Khur (Esfehan Province). At the Kuh-e Zaluband section has a maximum thickness of 100 m, consisting of marl, limestone, sandy limestone, sandstone and conglomerate and in the Kuh-e Hunu consisting of marl, limestone and sandy limestone. The lower part of the sections belonging to Farrokhi formation and upper part to Chupanan formation. Based of biostratigraphy at the study sections, summing up 88 thin sections were collected, among which the foraminifera with 17 specimens clearly predominate and belonging to 31 genera. Based on the foraminifera the age of the upper part of Farrokhi formation in the investigated area ranges Late Maastrichtian and Late Paleocene for lower part of Chupanan formation. Based on the paleontology, lithology and facies, there is disconformity in Cretaceous-Paleogene boundary in Kuh-e Zaluband and paraconformity in Kuh-e Hunu.
H Seif; M Majidifard; T Mohtat
Abstract
The Farrokhi formation in 15 km southwest of Khur with a thickness of up to 117m consists of marl and limestone with Maastrichtian age. In this section, the Farrokhi formation disconformably overlies the Haftoman formation below and the Chupanan formation above. In the present study, 87 genera and 103 ...
Read More
The Farrokhi formation in 15 km southwest of Khur with a thickness of up to 117m consists of marl and limestone with Maastrichtian age. In this section, the Farrokhi formation disconformably overlies the Haftoman formation below and the Chupanan formation above. In the present study, 87 genera and 103 species have been recognized. Based on foraminifera, the Farrokhi formation ranges from the Maastrichtian and 3 biozones in the rock unit 1 of the formation have been recognized: (1) Contusotruncana contuse Partial range zone (CF6), indexing Early Maastrichtian.(2) Pseudotextularia intermedia Partial range zone (CF5), index for late Early Maastrichtian index and (3) Racemiguembelin fructicosa Taxon Range Zone (CF4), an index for early Late maastrichtian. The Farrokhi formation can be subdivided into four rock units which are composed of marl and marly limestone. In addition, the Farrokhi formation fauna contains ostracods and high abundance of invertebrate as diverse species of brachiopods, echinoderms and bivalves with rare fragments of ammonites. The K/Pg boundary is in this section paraconform and can be compared with boundary of the Farrokhi and Chupanan formations. The evidence of paraconformity is a gap of Early Paleocene and changes in lithfacies. The Farrokhi formation is carbonate and it is parts of a carbonate system consisting of a platform and the adjacent slope.
F Chegeni; D Baghebani; S.H Vaziri; T Mohtat; N Kohansal Ghadimvand
Abstract
For the purpose of biozonation of the Pabdeh Formation (Middle-Upper Eocene) based on planktonic foraminifera, a stratigraphic section in the southern slope of the Mishan Mountain and another in the Eshgar Mountain were studied. The thickness of these sections is 162.5 and 150 meters, respectively. The ...
Read More
For the purpose of biozonation of the Pabdeh Formation (Middle-Upper Eocene) based on planktonic foraminifera, a stratigraphic section in the southern slope of the Mishan Mountain and another in the Eshgar Mountain were studied. The thickness of these sections is 162.5 and 150 meters, respectively. The Pabdeh Formation in the southern slope of the Mishan Mountain consists of marl, marly limestone, shale and limestone, and in the Eshgar Mountain includes alternating cream limestone and thin-bedded marl. In this study, most of the identified microfauna are Planktonic foraminifera. Identified Planktonic and benthic foraminifers in the southern slope of the Mishan Mountain include 18 genera and 8 species, and in the Eshgar Mountain include 21 genera and 10 species. Also four biozones are introduced of which one belongs to the Mishan Mountain and three belong to the Eshgar Mountain as follow: Hantkenina nuttalli Range Zone; Hantkenina nuttalli Turborotalia cerro-azulensis Interval Zone; Turborotalia cerro-azulensis Range Zone; Turborotalia cerro-azulensis/ Hantkenina sp. Assemblage Zone.
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 ...
Read More
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.
B Ghasemshirazi; M.R Majidifard; A Kheradmand; T Mohtat
Abstract
In this research, the Campanian -Maastrichtian deposits in Jupar section, Central Iran have been studied to determine biozonation and Paleobathymetry of the deposits. The planktonic and benthic foraminifera were studied in order to assign palaeobathymetry of the Campanian- Maastrichtian deposits. A depth ...
Read More
In this research, the Campanian -Maastrichtian deposits in Jupar section, Central Iran have been studied to determine biozonation and Paleobathymetry of the deposits. The planktonic and benthic foraminifera were studied in order to assign palaeobathymetry of the Campanian- Maastrichtian deposits. A depth of 490- 650 m was assigned for most parts of the sediments according to planktonic/epibenthic ratio and the regression equation D = e (3.58718+ (0.03534 × %P*)). In the present investigation, 58 planktonic species of 27 genera have been identified. The Campanian -Maastrichtian deposits is divided into 7 biozones 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, and Biozone7- Contusotruncana contusa Interval Zone.
L Bakhshandeh; T Mohtat; H Bakhshandeh; S Senmari
Abstract
The Ilam Formation, cropping out in the ZagrosMountain, consists of 195m of cream-colored limestones in the type section, south of Ilam city. This formation has conformable and continuous contacts with the lower Surgah and the upper Gurpi formations. In the present study, 35 foraminifera planktonic species ...
Read More
The Ilam Formation, cropping out in the ZagrosMountain, consists of 195m of cream-colored limestones in the type section, south of Ilam city. This formation has conformable and continuous contacts with the lower Surgah and the upper Gurpi formations. In the present study, 35 foraminifera planktonic species of 17 genus have been identified. The Ilam formation was divided into 4 cosmopolitan biozones on the basis of the planktonic foraminifera which, consist of: Biozone 1-Marginotruncana sigali -Dicarinella primitiva Partial Zone, Biozone 2- Dicarinella concavata Interval Zone, Biozone 3- Dicarinella asymetrica Total -range zone, and Biozone 4- Globotruncanita elevata Partial- range zone. According to these biozones, the Ilam formation was deposited from the late middle Turonian to the early Campanian.
E. Ghasemi-Nejad; M., Asadi; M. Shahmoradi; A. Aghanabati; T. Mohtat
Abstract
The Nayband Formation was sampled at Chal-Sefid and Zard mountains in central Iran, for palynology and palynostratigraphy in order to take the advantage of dinoflagellate cysts to locate the Triassic and so called Jurassic boundary. The Chal-Sefid section is located about 45 km southwest of Kashan city ...
Read More
The Nayband Formation was sampled at Chal-Sefid and Zard mountains in central Iran, for palynology and palynostratigraphy in order to take the advantage of dinoflagellate cysts to locate the Triassic and so called Jurassic boundary. The Chal-Sefid section is located about 45 km southwest of Kashan city and Zard Mountain some 70 km northeast of Esfahan. The studied strata attain a thickness of 1750 meters in Chal-Sefid and 1820 meters in Zard Mountain. They consists sandstone and shale beds. Totally 75 samples from Chal-Sefid and 22 samples from Zard Mountain were collected and treated in the Palynology laboratory of the Geological Survey of Iran. The recorded dinoflagellate cyst species were differentiated in four palynozones in Chal-Sefid and two palynozones in Zard Mountain as follows: Chal-Sefid section: Palynozone 1: Rhaetogonyaulax wigginsii, encompasses 160 meters of the section, suggesting an early to middle Norian age. Palynozone 2: Suessia listeri with a thickness of 140 meters, suggesting a middle Norian age. Palynozone 3: Hebecysta balmei encompasses 550 meters of the section, suggesting middle to late Norian age. Palynozone 4: Rhaetogonyaulax rhaetica with a thickneses of 900 meters suggests an early to middle Rhaetian age. Zard Mountain section: Palynozone 1: Hebecysta balmei, encompasses 442 meters of the section, suggesting a middle to late Norian age. Palynozone 2: Raetogonyaulax rhaetica, encompasses 491 meters of the section, suggesting an early to middle Rhaetian age. It is revealed that all the rock units investigated here are of late Triassic age and no evidence of Jurassic ages was identified.
L. Bakhshandeh; A. Aghanabati; T. Mohtat
Abstract
The first studied Abtalkh Formation with Campanian – Maastrichtian age is well exposed in Kopeh Dagh area (Mozduran section). This formation conformably underlain carbonates of Abderaz Formation and overlain by Neyzar sandeston Formation, both formations have a gradual contact.
The second studied ...
Read More
The first studied Abtalkh Formation with Campanian – Maastrichtian age is well exposed in Kopeh Dagh area (Mozduran section). This formation conformably underlain carbonates of Abderaz Formation and overlain by Neyzar sandeston Formation, both formations have a gradual contact.
The second studied formation so called Echinid marl formation of Santonian –Late Campanian age is exposed in Baharestan section, Central Iran, Esfehan area.
Based on 100 studied samples, there are litological and paleontological similarities between Abtalkh and Echinid marl formations. These evidences support strongly paleoecological and environmental similarities.
This ascertainment shows the close relation between the Kopeh Dagh and Central Iranbasins.
The fossil evidences found in both sections are as follow:
Globotruncana ventricosa (White), Globotruncanita elevata (Brotzen)
Globotruncana arca (Cushman), Globotruncanita stuartiformis (Dalbiez)
Globotruncana bulloides Volger, Globotruncana lapparenti Brotzen
Globotruncanita calcarata (Cushman), Globotruncana linneiana (d' Orbigny)
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˚ ...
Read More
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.
