List of Articles افیولیت

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  1 - Geochemical and Tectonomagmatic analysis of dibasic dikes and basaltic lavas in the Noorabad ophiolite (North-West Lorestan)
  Ahmad Ahmadi Khalaji mehrdad kiani Zahra Kamali Hadi Shafaei Moghadam asadollah kordnaeij
  The Noorabad ophiolite is a part of Eastern Mediterranean-Zagros-Oman Tethyan ophiolites, cropping out in south-southwest of the Main Zagros Thrust fault. In this sequence of the ophiolite rocks, diabase dikes and basaltic lavas are widespread. The chemical composition More

  The Noorabad ophiolite is a part of Eastern Mediterranean-Zagros-Oman Tethyan ophiolites, cropping out in south-southwest of the Main Zagros Thrust fault. In this sequence of the ophiolite rocks, diabase dikes and basaltic lavas are widespread. The chemical composition of these rocks comprise sub-alkaline basalts, andesitic basalt and andesite. According to normalized REE diagrams to the chondrite and trace elements normalized to the primitive mantle, these rocks show calc-alkaline series, the enrichment of LREE and LILE and depletion of HFSE elements. The characteristics of these ophiolites are similar to other exposed Tethyan ophiolites along Bitlis-Zagros suture zone, and their formation is associated with supra-subduction zones. Manuscript profile
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  2 - Structural style of the eastern part of Dehsheikh peridotite massif, Esfandagheh ophiolitic mélanges, Southwest of Iran
  Sahra Jalalat Vakil-Kandi Majid Shahpasandzadeh Mahdi Honarmand Hamid Ahmadipour
  The Dehsheikh peridotite massif, as a part of the Esfandagheh ophiolitic mélanges, is located in the south of Baft, Kerman province. Structural analysis of the ophiolitic complexes play an important role in understanding geodynamics of the orogenic belts. In this resear More

  The Dehsheikh peridotite massif, as a part of the Esfandagheh ophiolitic mélanges, is located in the south of Baft, Kerman province. Structural analysis of the ophiolitic complexes play an important role in understanding geodynamics of the orogenic belts. In this research, structural elements of the eastern part of the Dehsheikh peridotite massif as well as prevailing deformational patterns of the area and its relation to the Zagros orogenic belt was studied. The chromitite folds, dunitic/pyroxenitic dykes and ductile to brittle shear zones (faults and magnesite veins) constitute the principal structures of this area. Structural evidence indicate two successive tentional/transtentional and dextral transpressional deformational phases. The early D1 deformation took place in a back-arc basin during ascending of the Dehsheikh Peridotite massif. This caused emplacement of the lithospheric mantle in the low crust level, and was accompanied by deformation of the chromitites and intrusion of the dunitic/pyroxenitic dykes. The next D2 right-lateral transpressional deformation with development of the brittle-ductile shear zones accommodated emplacement of this massif in the high pressure-low tempretaure Sanandaj-Sirjan metamorphic zone. Manuscript profile
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  3 - Petrology and geochemistry of basic rocks of the Piranshahr Ophiolitic complex in Zagros belt (NW Iran), compared with the similar rocks from Iraqi Zagros ophiolitic complex
  Maryam Yazdani
  The Piranshahr ophiolitic complex is located in NW Iran and in the north west of Piranshahr town. Tectonically, the NW Piranshahr ophiolitic complex is severely mingled and the boundary of different units in this complex is indistinguishable. Piranshahr ophiolite includ More

  The Piranshahr ophiolitic complex is located in NW Iran and in the north west of Piranshahr town. Tectonically, the NW Piranshahr ophiolitic complex is severely mingled and the boundary of different units in this complex is indistinguishable. Piranshahr ophiolite includes ultramafic, mafic, sedimentary and metamorphic rocks. Basic rocks with basalt and diabase compositions are exposed in several parts of the region. In this paper, whole rocks geochemistry and petrogenesis of basic rocks were studied in the Piramshahr ophiolite (in the Mashkan and Gerdikavalan areas) and were compared with the geochemistry of basic rocks located in the west of Mawat ophiolite in Iraq (in the Hasanbag, Walash and Neopurdan regions). Composition of basic rocks of Mashkan area in Piranshahr ophiolite and Hasanbag area in Iraq ophiolite is calc-alkaline in nature and depleted with respect to MREE, HREE,Zr, Hf, Y, Ti elements and enriched in Rb, Cs, Ba, U, Th, Pb, LREE elements with negative Ta, Nb anomalies. These geochemical features show that the source of magma was generated in the supra-subduction zone tectonic settings. Composition of basic rocks of Gerdikavalan area in Piranshahr ophiolite and similar rocks in the Walash-Neopurdan areas in Iraq ophiolite represent tholeiitic nature. Tholeiitic nature in these areas show both MORB and volcanic arc affinity. It seems that the tholeiitic magma was probably generated in the lithospheric extension over on subduction zone and these features conform asupra-subduction setting for basic rocks in Piranshahr ophiolite and similar rocks in western continuation of Iraq ophiolitic complex. Manuscript profile
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  4 - Geochemical study of the soils provenance of The Gysian-Silvana-Urmia ophiolitic region
  zainab sadeghi Hossein Pirkharrati monir modjarrad Reza dehbandi
  Gysian ophiolite is a remnant of the Neotethys, located in the north-west Iran at the intersection of the ophiolite belts of south-eastern Turkey, north-eastern Iraq and north-western Iran. The geochemical comparison of the soils with the average of global rocks and the More

  Gysian ophiolite is a remnant of the Neotethys, located in the north-west Iran at the intersection of the ophiolite belts of south-eastern Turkey, north-eastern Iraq and north-western Iran. The geochemical comparison of the soils with the average of global rocks and the study area led to determination of the composition group of the region soils. The geochemical evidence of the first group of soil samples with low silica percentage by Harker and triangular diagrams is close to the position of ultramafic rocks of the region (serpentenites) and primary mantle and expresses their compositional similarity. The second group of soils ranges in the area between the earth's crust and basalt, and they show more distribution near basalt. The normalized pattern of REE rare earth elements in this group of soils is similar to the mafic rocks pattern in the region, also in the minor elements chart, they classified in the mafic group. Soils with high percentage of silica in the diagram of major and minor element oxides are located near the positiion of meta-plates rocks in the region, in the range between the earth's crust and global shale. So, this suggests the intermediate composition of their origin. Most likely, the tectonic setting of the three soil groups is based on the oxides of the main elements of the active continental margin. Manuscript profile
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  5 - Geochemistry and mineral chemistry of ultramafic rocks in the Koopan area, south of Bavanat (Fars Province)
  Maryam  Zurmand Sangari Ahmad Ahmadi Khalaji Kamal  Noori Khankahdani Zahra Tahmasbi
  20.1001.1.17357128.1403.18.69.1.8
  The studied area is located in the high Zagros zone and it is considered a part of the Neyriz ophiolite. In this area, the ophiolitic complex is small coloured melanges include radiolarite cherts and serpentinized ultrabasic rocks. The main lithological unit is serpen More

  The studied area is located in the high Zagros zone and it is considered a part of the Neyriz ophiolite. In this area, the ophiolitic complex is small coloured melanges include radiolarite cherts and serpentinized ultrabasic rocks. The main lithological unit is serpentinized ultrabasic rocks, which have a variety of colors from dark to light brown and dark to light green. These ultrabasic rocks have composed of olivine, pyroxene, amphibole, opaque, serpentine and spinel. Olivines have been highly altered to serpentine and pyroxenes to bastite. Based on whole rock chemistry, the studied rocks are basic and ultrabasic cumulates type (lherzolite-harzburgite) with a composition close to the average composition of the mid-ocean ridge basalt (MAR). Based on mineral chemistry, pyroxenes are calcic type and in the range of diopside and augite, and amphiboles are calcic and actinolite type. Pyroxenes have crystallized under conditions of low oxygen fugacity, temperature higher than 910 °C (1100 - 1200 °C) and pressure more than 2 kbar (2 to 10 kbar). Amphiboles have crystallized at a temperature below 700 °C and a pressure less than 1 kbar. Based on the geochemical characteristics and mineral chemistry, the ultrabasic rocks in the Koopan area were formed in a subduction zone. Manuscript profile
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  6 - Geochemistry of Central part of the Neo-Tethys Suture zone serpentinites (From NW Iran to Iraqi Zagros and Eastern Anatoly)
  monir modjarrad Mohsen Moayyed
  20.1001.1.17357128.1403.18.69.4.1
  The subduction and closure of the vast Neo-Tethys ocean between the Arabian and Eurasian plates has left numerous ophiolitic traces, the unique position of Iran in its central part is noticeable. The lack of information, right on the border of Iran with Iraq and Turke More

  The subduction and closure of the vast Neo-Tethys ocean between the Arabian and Eurasian plates has left numerous ophiolitic traces, the unique position of Iran in its central part is noticeable. The lack of information, right on the border of Iran with Iraq and Turkey, due to security considerations, has so far prevented the overview of this suture zone in the northwestern border of Iran. Adding Gysian ophiolite in southern Urmia as a missing link in this stretch can partially cover this lack of information. A comparative study of whole rock chemistry of serpentinites in the central part of the Neo-Tethys ophiolites, considering several sectors from Iran (Kamyaran, Marivan and Gysian), Iraq (Penjwin and Mawat) and Turkey (Guleman and Osmanie) in this article, indicates that they belong to subducted serpentinites, whether they were originally formed in the fore-arc environment or the at abyssal oceanic environment. Composition of the serpentinites of the central part of the suture zone is similar to the average global serpentinites which have mostly lizardite/chrysotile. All of them show depletion of Mg resulting sea floor alteration during serpentinization. The mentioned point may be caused to data deviation from abyssal peridotites field. Considering that the transition metals contents the confirmed the above setting. Almost all of the studied serpentinites are from subducted type which indicates refertilization of LILE evidences as a result of rock/fluid interaction through serpentinization. Manuscript profile