List of Articles Devonian

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  1 - Biostratigraphy, conodont biofacies and CAI of Late Devonian-Carboniferous deposits in Anarak section, Central Iran
  ٍٍElahe Sattari Ali Bahrami Hosyen Vaziri moghadam Ali Taheri Sandra Isabella  Kaiser Peter Königshof
  Study of Late Devonian-Carboniferous (Mississippian-Pennsylvanian) conodonts Anarak section (NE Isfahan), Central Iran, led to identifying 67 conodont species belonging to 18 genera. 22 conodont bio-intervals were separated; 15 biozones belong to Late Devonian and 7 b More

  Study of Late Devonian-Carboniferous (Mississippian-Pennsylvanian) conodonts Anarak section (NE Isfahan), Central Iran, led to identifying 67 conodont species belonging to 18 genera. 22 conodont bio-intervals were separated; 15 biozones belong to Late Devonian and 7 biozones belong to carboniferous (Mississippian-Pennsylvanian) time interval. Based on field observation and sedimentological featurs and charactristics the section, subdivided into 5 lithostratigrafic unit. The Color Alteration Index (CAI) reveals the hydrocarbure potential for the Famennian stage of the studied interval Manuscript profile
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  2 - Facies analysis and sedimentary environment of the Jeirud Formation in Garmabdar section, central Alborz: with emphasis on paleoredox conditions during deposition of black shales
  Nahid Karimi Najmeh  Etemad-Saeed Aram Bayet-Goll Afshin  Zohdi Tomas Kumpan
  The late Devonian has been associated with major global climate changes, widespread anoxia events, and the Hangenberg Crisis. The main aim of this study is to explore the relationship between paleoenvironment and paleoredox condition during deposition of the lower Devon More

  The late Devonian has been associated with major global climate changes, widespread anoxia events, and the Hangenberg Crisis. The main aim of this study is to explore the relationship between paleoenvironment and paleoredox condition during deposition of the lower Devonian Jeirud Formation in the Garmabdar section, northeast of Tehran. The Jeirud Formation in the Garmabdar section, with a thickness of about 280 m, is composed of siliciclastics, carbonates, carbonate-siliciclastic hybrids and phosphorite deposits. Sedimentary facies analysis led to recognition of three siliciclastic facies associations related to estuarine environments under the influence of waves, shoreface and offshore and two carbonate facies associations related to intertidal and subtidal environments. Moreover, the geochemical paleoredox proxies (such as U/Th and V/Cr) also suggest prevailing anoxic conditions during deposition of black shales and phosphorites in the studied section. In overall, these results suggest that there is a good agreement between the depth of the depositional environment and anoxic conditions during deposition of black shales of the Jeirud Formation. Manuscript profile
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  3 - Biostratigraphy, biofacies and CAI of the late Devonian deposits in Kale-Sardar section, North-east Tabas, based on conodont fauna
  Mina Ramshini ٍٍElahe Sattari Ali Bahrami Hosyen Vaziri moghadam
  10.61186/ispg.41138.11.22.1
  Kale-Sardar section, is located at the vicinity of Niaz village, 15 kilometers east of Tabas town. This section consists of 80 m thick and from Late Devonian deposits as known as Shishtu formation that upper part of this section has cut by a fault by Frasnian’s deposits More

  Kale-Sardar section, is located at the vicinity of Niaz village, 15 kilometers east of Tabas town. This section consists of 80 m thick and from Late Devonian deposits as known as Shishtu formation that upper part of this section has cut by a fault by Frasnian’s deposits. The entire studied thickness is subdivided into 12 lithostratigraphic units and in order to study of conodont elements, 27 species and subspecies belonging to 7 genera were recognized, that due to these revealed conodont elements, Shishtu formation’s age in the studied section spans from Eifelian to late Frasnian. The Frasnian-Famennian bio event in studied section is located between two intervals linguiformis Zone and Lower to Middle triangularis zones which is located at the top of the dark Frasnian shales and at the base of the thin limestones of the Famennian layer. The microfacies determined in studied section are subdivided into siliciclastic-carbonate and carbonate facies, which were deposited from the shore to the deep part of the marine environment. Gradual changes in facies within stratigraphical sequence, sedimentological hiatus due to sudden change in sedimentary environment’s slope, absence of reef facies (related to Wilson’s 5th facies zone) and presence of discontinuous bioclastic barrier (existence of semi-enclosed lagoon), convey that studied sediments were deposited in a homoclinal carbonate ramp. Manuscript profile
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  4 - Reconstruction of Jeirud Formation depositional environment in Aro Section (Central Alborz)
  Seyed Mohammad Zamanzadeh M. Ranjbaran K. Ghaffari
  In this paper it is attempted to reconstruct the depositional environment of the Jeirud Formation in Aro section. The Jeirud Formation (Late Devonian) is composed of about 45 meters of clastic sedimentary units in the southwest of Firoozkuh city, southern Alborz area. T More

  In this paper it is attempted to reconstruct the depositional environment of the Jeirud Formation in Aro section. The Jeirud Formation (Late Devonian) is composed of about 45 meters of clastic sedimentary units in the southwest of Firoozkuh city, southern Alborz area. To carry out this research a field work was done during which a precise and detailed sedimentary log of the section was prepared and 52 samples from different lithologies of the formation were collected. Thin sections were prepared from all conglomeratic and sandstone samples, besides some thin sections were prepared from mudrocks and just 1 sample of paleosoil and then all were petrographically studied. In the study area, both basal and top boundary of the Jeirud Formation is disconformable with Mila and Mobarak formations respectively. All facies in the section include clastics (conglomerates, sandstones, mudstones and a paleosoil horizon). The facies were classified based on Miall classification so that conglomeratic facies comprise Gcm and Gmm; sandstone facies comprise Sh, Sp and Sm and mudrocks include Fl and Fm facies. Combined field and lab studies resulted in identification of two sedimentary facies associations including channel fill and flood plain facies associations. The reconstructed sedimentary environment of the Jeirud Formation in the Aro area represents a braided river depositional environment. The lower parts of this formation represent a finning-upward sequence which indicates deposition within a braided river channel subenvironment (conglomerates and sandstones) and the upper part is dominated with mudrocks with a paleosoil horizon representing deposition in a flood plain subenvironment. Manuscript profile