Stratigraphy and Palaeontology
Hamideh Noroozpour
Abstract
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 ...
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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.
Stratigraphy and Palaeontology
Mahin mohamadi; R. Shabanian; H. M. Alizadeh
Abstract
This research has aimed to study the biostrtigraphy and lithostratigraphy of late cretaceous deposits in south of Maracan village , with 320 m thickness.This sequence overlaid the lower cretaceous deposits and have been covered by Quaternary sedimentary and magmatic rocks. Based on field ...
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This research has aimed to study the biostrtigraphy and lithostratigraphy of late cretaceous deposits in south of Maracan village , with 320 m thickness.This sequence overlaid the lower cretaceous deposits and have been covered by Quaternary sedimentary and magmatic rocks. Based on field study and lithological diversity 8 lithic zone have been investigated. 102 samples have been picked up systematically from this sequence. This study lead to determining 41 species from 15 genera of planktonic foraminifera.The systematic and classification of fauna are based on The (Postuma 1971) , (Caron1985) , (Loeblich and Tappan 1988) and (Permoli Silva And Verga 2004). .Based on their range chart the bio zonation model for this deposit with 9 Bio Zones as bellow have been suggested and have compared with cretaceous global standard bio zones (Robazynsky and Caron 1985) and (Permoli Silva and Verga, 2004) Dicarinella concavata Interval Zone (Robazynsky and Caron, 1995) Dicarinella asymetrica Total range Zone(Robazynsky and Caron, 1995) Globotruncanita elevata IntervalrangeZone(Robazynsky and Caron, 1995) Globotruncana ventricosa IntervalZone (Robazynsky and Caron, 1995) Rodotruncana calcarata Total range Zone(Robazynsky and Caron, 1995) Globotruncanella havnensis Partial Range Zone (Robaszynski and Caron, 1985) Globotruncana aegyptiaca Interval Zone (Robazynsky and Caron, 1995) Gansserina gansseri Interval Zone (Robazynsky and Caron, 1995) Abathamphalus mayaroensis Total range Zone(Robazynsky and Caron, 1995) The suggested age for th.is sequence based on planktonic foraminifera is upper coniantian to upper Maestrichtian and belong to deep shelf area . Based on the morphology of planktonic foraminifera and their keei we suggest deep sea environment for these deposits.
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 ...
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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.
M. R. Esmaeilbeig
Abstract
The study of planktonic foraminifera of the Gurpi Formation at Kuh-e Khane Kat (east of Shiraz) led me to find standard biozones from Early Santonian to Middle Campaninan. Four biozones were determined: biozones I (Dicarinella asymetrica zone) and II (Rosita fornicata zone) belong to Early and Late Santonian. ...
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The study of planktonic foraminifera of the Gurpi Formation at Kuh-e Khane Kat (east of Shiraz) led me to find standard biozones from Early Santonian to Middle Campaninan. Four biozones were determined: biozones I (Dicarinella asymetrica zone) and II (Rosita fornicata zone) belong to Early and Late Santonian. Biozones III (Globotruncanita stuartiformis zone) and IV (Globotruncana ventricosa zone) represent the Early and Middle Campaninan. Due to a decrease in water depth in Kuh-e Khane Kat, Globotruncanita calcarata zone and other Maastrichtian plagic biozones were not recognized. In this section, Gurpi Formation is 220.5 meters thick and contains shale and argillaceous limestone. Its underlying and overlying formations are Sarvak and Tarbur.
P. Rajabi; I. M. Moghadam; F. Gharib
Abstract
In this study, the Sediments of Taleh-Zang Formation was investigated in South West of Khoramabad. The thickness of Taleh-Zang Formation in Qalebi section measured 200m. In this section the sediment of Taleh-Zang Formation is isoclines between Amiran Formation at the base, and Kashkan Formation at the ...
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In this study, the Sediments of Taleh-Zang Formation was investigated in South West of Khoramabad. The thickness of Taleh-Zang Formation in Qalebi section measured 200m. In this section the sediment of Taleh-Zang Formation is isoclines between Amiran Formation at the base, and Kashkan Formation at the top. This Formation composed of gray limestone with chert nodules and Sandy Limestone. The study of samples taken from the studied section led to identification 28 genera and 4 species of benthonic Foraminifera and 6 genera and 2 species of green algae. The benthonic Foraminifera of the measured section were used to recognized the age of Succession and justify their correlation Based on the recognized Foraminifera such as Miscellanea miscella. The Qalebi section is Comparable to biozonation introduced by Wynd (1965). It is analogous to Miscellanea – Kathina assemblage zone (No# 43). According to distribution of the index Foraminifera, the age of the Sediments in Qalebi Section is Thanetian.
R. Azimi; K. Seyed-Emami; A. Sadeghi
Abstract
The calpionellid biozonation within Shal and Kolur Formations in Shal region, SE Khalkhal are accomplished based on standard biozonation of Allemann et al. (1977). In this study, 5 biozones are introduced from Tithonian to Hauterivian:biozone. Biozone 1 belongs to Shal Formation ...
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The calpionellid biozonation within Shal and Kolur Formations in Shal region, SE Khalkhal are accomplished based on standard biozonation of Allemann et al. (1977). In this study, 5 biozones are introduced from Tithonian to Hauterivian:biozone. Biozone 1 belongs to Shal Formation and biozones 2 to 5 to Kolur Formation: 1- Crassicollaria intermedia Taxon Range Zone; Late Tithonian, 2- Calpionella alpina Acme Zone; Early Berriassian, 3- Calpionellopsis simplex - Calpionellites darderi Interval Zone; Late Berriassian to Early Valanginian, 4- Calpionellites darderi - Tintinopsella longa Interval Zone; Valanginian, 5- Tintinopsella longa - Tintinopsella carpathica Interval Zone; Late Valanginian- Hauterivian. Biozone 2 is also subdivided into the Calpionella alpina and Calpionella elliptica Subzones. Biozone 3 is subdivided into the Calpionellopsis simplex and Calpionellopsis oblonga Subzones. Based on this zonation, the Jurassic /Cretaceous boundary (Tithonian/ Berriassian) is defined at the Lower boundary of the Calpionella alpina zone which is equivalent to the Shal and Kolour Formations boundary.
S.H. Vaziri; D. Jahani; M. Safdari; F. Chegeni
Abstract
The Ilam Formation in southwestern Khorram Abad with a thickness of up to 204 meters consists of uniform limestones with Middle Turonian to Early Campanian age which were deposited in a continuous sedimentation process. In this section, the Ilam Formation has continuous ...
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The Ilam Formation in southwestern Khorram Abad with a thickness of up to 204 meters consists of uniform limestones with Middle Turonian to Early Campanian age which were deposited in a continuous sedimentation process. In this section, the Ilam Formation has continuous and transitional contacts with the Sourgah Formation in the lower boundary and the Gurpi Formation in the upper boundary. In the present study, 9 genera, 30 species and 2 biozones of the planktonic foraminifera have been recognized. The Ilam Formation in the studied section consists of a shaly facies and three carbonatic microfacies include mudstone, wackestone and packstone containing planktonic foraminifera. Shaly facies and mentioned microfacies were deposited in deep-open marine, which formed in a quiet environmental condition and increased environmental energy in microfacies with mudstone texture toward microfacies with wackestone and packstone textures. Whereas in the studied section recognized microfacies are not related to parts of continental shelf,such as ; bar, lagoon and tidal flat, therefore it could be said that, the studied area was part of profound depositional basin in Middle Turonian to Early Campanian.