Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting

The Neogene post-collisional volcanism in eastern Iran is represented by the Sikh Kuh and Bobak high-Na rocks including trachybasalt, trachyandesite, trachydacite, and dacite. We report whole rock geochemistry and Nd–Sr isotopic data which constrain the characteristics of the mantle source. The rock...

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Main Authors: Biabangard, H, Sepidbar, F, Palin, RM, Boomeri, M, Whattam, SA, Homam, SM, Shahraki, OB
Format: Journal article
Language:English
Published: Springer 2022
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author Biabangard, H
Sepidbar, F
Palin, RM
Boomeri, M
Whattam, SA
Homam, SM
Shahraki, OB
author_facet Biabangard, H
Sepidbar, F
Palin, RM
Boomeri, M
Whattam, SA
Homam, SM
Shahraki, OB
author_sort Biabangard, H
collection OXFORD
description The Neogene post-collisional volcanism in eastern Iran is represented by the Sikh Kuh and Bobak high-Na rocks including trachybasalt, trachyandesite, trachydacite, and dacite. We report whole rock geochemistry and Nd–Sr isotopic data which constrain the characteristics of the mantle source. The rocks are highly enriched in incompatible trace elements, suggesting a metasomatized subcontinental lithospheric mantle (SCLM) as the magma source. Felsic rocks record abundant petrographic evidence, major and trace element data, and isotopic (87Sr/86Sr(i) = 0.70727–0.70902) signatures indicative of fractional crystallization, and potentially, crustal assimilation. Such processes however, have not significantly affected the isotopic signatures (87Sr/86Sr(i) = 0.70417–0.70428) of the mafic members, suggesting that they are derived from a mantle source. The geochemical and isotopic data for the Sikh Kuh and Bobak volcanic rocks suggest that these Neogene magmas were derived from a small degree of partial melting (~ 2–10 vol%) of a spinel-bearing subcontinental lithospheric mantle source in a post-collisional setting. The generated more unfractionated mafic magmas erupted during an episode of extensional tectonics, presumably caused by extension that followed Eocene collision between the Lut and Afghan continental blocks. These melts interacted with continental crust during ascent, experiencing crystal fractionation, and crustal assimilation, to produce more evolved felsic volcanic rocks.
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spelling oxford-uuid:73840e95-6b7f-44e3-8de5-25838aa4cfb32024-04-26T14:37:10ZNeogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic settingJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:73840e95-6b7f-44e3-8de5-25838aa4cfb3EnglishSymplectic ElementsSpringer2022Biabangard, HSepidbar, FPalin, RMBoomeri, MWhattam, SAHomam, SMShahraki, OBThe Neogene post-collisional volcanism in eastern Iran is represented by the Sikh Kuh and Bobak high-Na rocks including trachybasalt, trachyandesite, trachydacite, and dacite. We report whole rock geochemistry and Nd–Sr isotopic data which constrain the characteristics of the mantle source. The rocks are highly enriched in incompatible trace elements, suggesting a metasomatized subcontinental lithospheric mantle (SCLM) as the magma source. Felsic rocks record abundant petrographic evidence, major and trace element data, and isotopic (87Sr/86Sr(i) = 0.70727–0.70902) signatures indicative of fractional crystallization, and potentially, crustal assimilation. Such processes however, have not significantly affected the isotopic signatures (87Sr/86Sr(i) = 0.70417–0.70428) of the mafic members, suggesting that they are derived from a mantle source. The geochemical and isotopic data for the Sikh Kuh and Bobak volcanic rocks suggest that these Neogene magmas were derived from a small degree of partial melting (~ 2–10 vol%) of a spinel-bearing subcontinental lithospheric mantle source in a post-collisional setting. The generated more unfractionated mafic magmas erupted during an episode of extensional tectonics, presumably caused by extension that followed Eocene collision between the Lut and Afghan continental blocks. These melts interacted with continental crust during ascent, experiencing crystal fractionation, and crustal assimilation, to produce more evolved felsic volcanic rocks.
spellingShingle Biabangard, H
Sepidbar, F
Palin, RM
Boomeri, M
Whattam, SA
Homam, SM
Shahraki, OB
Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title_full Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title_fullStr Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title_full_unstemmed Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title_short Neogene calc-alkaline volcanism in Bobak and Sikh Kuh, Eastern Iran: implications for magma genesis and tectonic setting
title_sort neogene calc alkaline volcanism in bobak and sikh kuh eastern iran implications for magma genesis and tectonic setting
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