List of Articles کرتاسه

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  1 - Late Cretaceous Island-arc subduction magmatism in northern edge of central Iran, SW Sabzevar
  Elham Mirzakazemi Habibollah Ghasemi Fardin Mousivand Wilyam Griffin
  A thick sequence of Late Cretaceous volcano-sedimentary rocks crops out on the northern margin of Central Iran, in the southwest of the Sabzevar. The igneous rocks include extrusions (trachy-andesite, dacite and rhyolite) and shallow depth intrusions (gabbro, gabbrodior More

  A thick sequence of Late Cretaceous volcano-sedimentary rocks crops out on the northern margin of Central Iran, in the southwest of the Sabzevar. The igneous rocks include extrusions (trachy-andesite, dacite and rhyolite) and shallow depth intrusions (gabbro, gabbrodiorite, diorite and granite). These igneous rocks have geochemical signatures of magmatic rocks of island-arc subduction zones and plot within field in different tectonic setting discrimination diagrams. The parental magma of these rocks has island arc tholeiitic nature and was produced via partial melting of a depleted spinel lherzolite mantle source during closing of the Sabzevar Neo-Tethyan oceanic basin in the Late Cretaceous. This depleted mantle source was affected by the metasomatic fluids released from dehydration of the Neo-Tethys subducted oceanic slab. Manuscript profile
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  2 - Microfacies and sedimentary environment of Lower Cretaceous deposits in Qumenjan section, south west of Qayen
  Hourieh Zarei Seyed Naser Raisossadat M. Mortazavi M. Yazdi
  In order to study the Lower Cretaceous deposits, Qumenjan section has been selected and measured. Field and lab studies of the Lower Cretaceous deposits in this section reveal a gradual change of the depositional setting, from a fluvial depositional system (continental More

  In order to study the Lower Cretaceous deposits, Qumenjan section has been selected and measured. Field and lab studies of the Lower Cretaceous deposits in this section reveal a gradual change of the depositional setting, from a fluvial depositional system (continental environment) to a mixed siliciclastic- carbonate ramp (marine environment). The continental deposits of the studied section include conglomerate and sandstone lithofacies that are deposited in a proximal gravel- bed braided river. In the studied sedimentary sequence, the marine siliciclastic- carbonate facies associations are formed in three tidal flat, lagoon and shoal facies belt in the inner and mid ramp setting. Manuscript profile
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  3 - Calcareous nannofossil biostratigraphy in the upper part of the Garau Formation in the Sheikh Saleh section in Northwest of Kermanshah, Lurestan Province (Zagros Basin)
  سعیده  سنماری
  In this study, the upper part of the Garau Formation with a thickness of 24 m in the section of Sheikh Saleh anticline located in the northwest of Kermanshah was investigated from the calcareous nannofossils. In this section, the Garau Formation is mainly composed of me More

  In this study, the upper part of the Garau Formation with a thickness of 24 m in the section of Sheikh Saleh anticline located in the northwest of Kermanshah was investigated from the calcareous nannofossils. In this section, the Garau Formation is mainly composed of medium bedded argillaceous limestone. In order to introduce the index species and biozones, 17 slides from the Garau Formation were studied, which resulted in the identification of three biozones. As a result of this study, 20 species and 15 genera of calcareous nannofossils were identified. Based on the obtained biozones, the age of the upper part of the Garau Formation in the studied section is suggested the late early Cenomanian to the late late Cenomanian. This age is corresponding to the upper part of Eiffellithus turriseiffelii Zone (CC9), Microrhabdulus decorates Zone (CC10), lower part of Quadrum gartneri Zone (CC11) from the Sissingh (1977) zonation and UC1, UC2, UC3, and lower part of UC7 from the Burnett (1998) zonation. Manuscript profile
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  4 - Biostratigraphy of Dariyan Formation in Lar Anticline (north east Gachsaran) and Lower Cretaceous sediments in Kolah Ghazi section (South west Isfahan)
  Mahdie Shirzad Hosyen Vaziri moghadam Ali Bahrami
  In order to identify foraminifera and determine the age of Dariyan Formation and the lower Cretaceous sediments of Central Iran, a section of Dariyan Formation in Lar Anticline (northeast Gachsaran) (with a thickness of 111m, thick, medium and thin layer of limestone, m More

  In order to identify foraminifera and determine the age of Dariyan Formation and the lower Cretaceous sediments of Central Iran, a section of Dariyan Formation in Lar Anticline (northeast Gachsaran) (with a thickness of 111m, thick, medium and thin layer of limestone, marl and marly limestone) and Kolah Ghazi section (south west Isfahan) (with a thickness of 260m, thick to medium layer limestone and shale) were studied. Based on biostratigraphic studies of Lar Anticline section, 28 benthonic foraminifera and 4 planktonic foraminifera have been identified in 4 biozones contains: Hedbergellids - Orbitolinids assemblage zone, Mesorbitolina texana zone, Mesorbitolina gr. subconcava zone, Favusella washitensis rang zone. Based on biostratigraphic of Lower Cretaseous sediments in Kuh-e-Kolah Ghazi, 21 benthonic foraminifera and 1 planktonic foraminifera have been identified and consequently 2 biozones are recognized contains: Mesorbitolina texana zone, Mesorbitolina gr. subconcava zonethe studied areas were correlated with some sections of the Dariyan in Kuh-e-Fahliyan, Kuh-e- Mangasht and Meymand. Accordingly, the sedimentation of two studied sections in Lar Anticline and Kuh-e-Kolah Ghazi were started from Late Aptian which were later than the other sections, and the end of sedimentation in the Kuh-e-Kolah Ghazi was earlier than the other sections in the Late Aptian age, while the end of sedimentation of Dariyan Formation in other sections was in Early Albian age Manuscript profile
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  5 - Calcareous nannofossil biostratigraphy of the Cretaceous deposits in Khunik startigraphic section (West Qaen, eastern Iran)
  M. Notghi Moghaddam F. Jalili S. Senemari
  In this research, the biostratigraphy of the Cretaceous deposits was investigated in the eastern margin of Lut Block in Khunik startigraphic section, west of Qaen, based on calcareous nannofossils. The stratigraphic interval mainly consists of marls with sandstone inter More

  In this research, the biostratigraphy of the Cretaceous deposits was investigated in the eastern margin of Lut Block in Khunik startigraphic section, west of Qaen, based on calcareous nannofossils. The stratigraphic interval mainly consists of marls with sandstone interlayers (196 m thick). According to the systematic studies, 30 nannofossil species belonging to 20 genera were identified. Based on the presence of index calcareous nannofossils such as Calcicalathina oblongata, Speetonia colligata, Eiffellithus striatus and the fossil assemblages Calcicalathina oblongata Zone (CC3), Cretarhabdus loriei Zone (CC4) and Lithraphidites bollii Zone (CC5) these deposits are equivalent to NK3A subzone – middle part of NC5B subzone. According to the determined biozones, early Valanginian to late Hauterivian age was suggested for the studied interval. Manuscript profile
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  6 - Biostratigraphy and paleoecology of Family Gavelinellidae in Sanganeh and Aitamir Formations at the Kopeh-Dagh basin
  Maryam Motamedalshariati Mahmoud Jalali
  10.61186/ispg.41339.11.22.89
  The sedimentary basin of Kopeh-Dagh is located in the northeast of Iran. This sedimentary basin has been of interest for a long time because of hydrocarbon materials. Gavelinellids are the most abundant and dominant groups of benthic foraminifera in epicontinenal seas d More

  The sedimentary basin of Kopeh-Dagh is located in the northeast of Iran. This sedimentary basin has been of interest for a long time because of hydrocarbon materials. Gavelinellids are the most abundant and dominant groups of benthic foraminifera in epicontinenal seas during Cretaceous period which belong to Rotaliinacean foraminifera. They have shown a wide biogeographical distribution and dispersion in many areas of Tethys. Their evolutionary trend during the Cretaceous time was success. The high concentration of marine sedimentary rocks and the absence of igneous activities in the Kope-Dagh sedimentary basinhave caused it to be considered the most suitable basin for the formation and accumulation of hydrocarbons after the Zagros sedimentary basin. This basin has suitable layers of carbonate rocks and porous sandstones to store hydrocarbon materials, also thick layers of shales in this basin can act as suitable source and cap rocks. In this research some genera and species from this family in Sanganeh and Aitamir Formations at five stratigraphic sections including Marave Tappeh, Takal kuh, Sheykh, Gadvecanlou and Kalat from point of biostratigraphical and paleoecological applications have been investigated. In this study, four biozones including Gavelinella flandrini-Gaudryina cf. praedividens assemblage zone, Berthelina intermedia assemblage zone, Berthelina cenomanica Assemblage Zone, Berthelina intermedia-Osangularia schloenbachi Assemblage Zone have been introduced. Based on the reported genera and species of the Gavellinidae family, it can be stated that the studied formations were deposited in the middle and outer part of the continental shelf to the upper part of the continental slope and in aerobic to semi-aerobic environments. The presence of more planktonic foraminifera than benthic foraminifera in the Aitamir Formation, the depth of the basin increases. Manuscript profile
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  7 - Global record of oceanic anoxic event in the carbonates of the Daryian Formation in the northern High Zagros, Zargran mountain (Gadvan)
  Mazaher Yavari M. Yazdi Hormoz Ghalavand Mohammad Hossein Adabi
  The recording of oceanic anoxic event al record and the time of this event in the shallow carbonates of the Dariyan Formation in Zargran mountain (Gadvan) section in the east of Shiraz, was studied based on carbon and oxygen isotopes, microfacies and fossil data. More

  The recording of oceanic anoxic event al record and the time of this event in the shallow carbonates of the Dariyan Formation in Zargran mountain (Gadvan) section in the east of Shiraz, was studied based on carbon and oxygen isotopes, microfacies and fossil data. In this section, thickness of the Dariyan Formation is 287 m and 191 samples were taken. Based on field data, the sedimentary sequence of this formation, , begins at the base with thick-layered to massive gray limestones containing orbitolinas and rudists, and in the upper parts it includes medium to thick-layered gray limestones including abundant benthic foraminifera, such as orbitolinas. In the mentioned section, based on the study of the embryonic cells of orbitolinas, a late Barmian-early Aptian age was determined for the lower part of this unit, which is the beginning of the formation of anoxic oceanic deposits. The carbon isotope curves between the C3 and C6 curves in the carbonates at the base of the Daryian Formation show disturbances. These changes and the appearance of the Lithocodium-Bacinella facies in this part of the formation confirm the existence of an oceanic anoxic event. The oceanic anoxic event indicates warming of the environment and greenhouse conditions, which was accompanied by abundant rudists in this section and can be a confirmation for the weather conditions of this event. Manuscript profile