Supra-subduction

List of Articles Supra-subduction

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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 - Investigations on the geotectonic environment of Abdasht peridotites, SE Kerman Province, using spinel chemistry
Tayabeh Roudbari Mohsen Moazzen Seyed Hesamedin Moeinzadeh Abdolmajid ahangari

Peridotites are one of the main rock types of the Abdasht ophiolitic complex in southern Iran. Peridotites of this ophiolite are dunite and harzburgite. The important original minerals in the peridotites include olivine, orthopyroxene, spinel and to the lesser amounts, More

Peridotites are one of the main rock types of the Abdasht ophiolitic complex in southern Iran. Peridotites of this ophiolite are dunite and harzburgite. The important original minerals in the peridotites include olivine, orthopyroxene, spinel and to the lesser amounts, clinopyroxene. Study of the chemistry of spinel in these peridotites shows that their composition, based on the end-member chemistry, is Spl0.4 Chr0.57 Mag0.03 to Spl0.46 Chr0.51 Mag0.03. The chromium number (Cr#) varies from 0.73 to 0.92 and the Al2O3 contents are3.61 to 11.29 wt%. The chemical compositions show that spinel is mantle residua phase and its high Cr content indicates the peridotites depletion. Spinel chemistry shows that the studied peridotites are related to supra-subduction environment at a fore-arc setting with boninitic features. 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 - Petrology and geochemistry of Siahjangal ophiolite, northeastern Taftan volcano
saeideh Nikbakht حبیب بیابانگرد Sasan Baghari
20.1001.1.17357128.1399.14.56.2.5

Siahjangal ophiolite is located in the North and Northeastern part of Taftan volcano in the Sistan Suture Zone (SSZ). This ophiolite (Upper Cretaceous) is exposed in the Flysch rocks (Eocene). Harzburgite, lherzolite, serpentine, spilite and gabbro are major rocks in th More

Siahjangal ophiolite is located in the North and Northeastern part of Taftan volcano in the Sistan Suture Zone (SSZ). This ophiolite (Upper Cretaceous) is exposed in the Flysch rocks (Eocene). Harzburgite, lherzolite, serpentine, spilite and gabbro are major rocks in this ophiolite. Ultramafic units have olivine, orthopyroxene and clinopyroxene minerals. Mafic units have clinopyroxene and plagioclase. Ultramafic rocks have mainly granular and gabbro rocks have ophitic, sub-ophitic and granular textures. Geochemical verities of major, minor and rare earth elements in the Siahjangal ophiolite revealed that the ultrabasic and basic rocks were formed due to partial melting than crystal differentiation. REE elements diagrams normalized to the Chondrite and MORB and their comparison with the normal and enriched MORBs, chemical differentiation diagrams, the ratios of accessory elements and changes of Zr, Nb, Y, U, Ti elements against Zr / Nb ratio all indicates the similarity to N-MORB. Transition elements diagrams (V, Co, Cr, Ni) against La / Ce ratio and the ratio of (La / Yb) N, La / Yb, La / Ce versus (La / Sm) N, show that these ratios compared with N-MORB and E-MORB represent enrichment and geochemical similarities to N-MORB. Tectonomagmatic diagrams show Siahjangal ophiolite belongs to supra-subduction zone. Manuscript profile

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List of Articles Supra-subduction