TY - JOUR

T1 - Geochemical and isotopic features of the Early Cretaceous volcanism of the Torey Volcanic Field (Eastern Transbaikalia, Russia) as a record of the transition from pyroxenite to eclogite mantle source

AU - Savatenkov, V.M.

AU - Kuznetsov, M.V.

AU - Shpakovich, L.V.

N1 - Export Date: 19 October 2024 Адрес для корреспонденции: Kuznetsov, M.V.; Laboratory of Geochronology and Geochemistry of Isotopes, 2 Makarova emb., Russian Federation; эл. почта: garneteclogite@gmail.com Сведения о финансировании: Russian Science Foundation, RSF, 23-27-00165 Сведения о финансировании: Russian Science Foundation, RSF Текст о финансировании 1: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Maksim Kuznetsov reports financial support was provided by Russian Science Foundation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.This study was supported by a grant from the Russian Science Foundation \u2116 23-27-00165, https://rscf.ru/project/23-27-00165/. The fieldwork and rock sampling were carried out with the support of the administration of the State Nature Boisphere Reserve \u201CDaursky\u201D. The authors are deeply grateful to Dr. Aaron Pietruszka, Assistant Professor at the School of Ocean and Earth Science and Technology at the University of Hawai\u02BBi at M\u0101noa, and Reed Mershon, Graduate Assistant at the School of Ocean and Earth Science and Technology at the University of Hawai\u02BBi at M\u0101noa, for their invaluable help in revising the manuscript. Текст о финансировании 2: This study was supported by a grant from the Russian Science Foundation \u2116 23-27-00165 , https://rscf.ru/project/23-27-00165/ . The fieldwork and rock sampling were carried out with the support of the administration of the State Nature Boisphere Reserve \u201CDaursky\u201D. The authors are deeply grateful to Dr. Aaron Pietruszka, Assistant Professor at the School of Ocean and Earth Science and Technology at the University of Hawai\u02BBi at M\u0101noa, for his invaluable help in revising the manuscript.

PY - 2024/11/1

Y1 - 2024/11/1

N2 - The Mesozoic magmatic activation in Central and Northeast Asia resulted in the formation of a large volume of volcanic rocks with diverse compositions. The most dramatic compositional change occurred at the end of the Early Cretaceous, when mainly alkaline basaltic lavas began to erupt after subalkaline differentiated lavas. The nature of crustal and mantle processes that led to this change in volcanism remains unclear. The Torey Volcanic Field (TVF) of Eastern Transbaikalia (Russia) demonstrates a similar compositional change. Therefore, the TVF is crucial to studying the cause of the difference in geochemical and isotopic signatures of the Mesozoic volcanism in Central and Northeast Asia. TVF belongs to the northeastern end of the Eastern Mongolia Volcanic Area (EMVA). Like other volcanic fields of the EMVA, TVF formed in two stages: early (∼121–129 Ma) and late (∼101–119 Ma). The TVF is composed of subalkaline and alkaline basaltic trachyandesites – trachyandesites. All TVF rocks are characterized by negative Ti and Sr anomalies and positive Ba and Pb anomalies. Compared to the late TVF rocks, the early TVF rocks have distinct negative Ta and Nb anomalies and are highly enriched in light rare earth elements relative to heavy rare earth elements. TVF rocks have the following isotopic characteristics: 87Sr/86Sr(t) = 0.70477–0.70540, εNd(t) = − 0.9 – +2.4, 206Pb/204Pb(t) = 17.9–18.4, and 207Pb/204Pb(t) = 15.5–15.6. However, older rocks mainly have higher εNd(t) values and 206Pb/204Pb(t) and 207Pb/204Pb(t) ratios. Geochemical and isotopic data of samples suggest that the TVF formed by melting in the continental metasomatized lithospheric mantle (CMLM). Phlogopite-amphibole-rutile-bearing pyroxenite veins played a major role in the formation of older rocks. Eclogite, represented by the recycled oceanic crust or the buried lower continental crust, was dominant in the source of younger rocks. The common source for both groups of the TVF rocks was metasomatized hydrous peridotite. Lithospheric extension and subsequent asthenospheric upwelling led to melting in the CMLM and the formation of the TVF. At the early stage of the volcanism, melting occurred at relatively low temperatures where amphibole, phlogopite, and rutile were stable. Due to ongoing lithosphere extension, the melting of eclogite occurred at a higher temperature and/or lower pressure at the late stage of the volcanism. © 2024 Elsevier B.V.

AB - The Mesozoic magmatic activation in Central and Northeast Asia resulted in the formation of a large volume of volcanic rocks with diverse compositions. The most dramatic compositional change occurred at the end of the Early Cretaceous, when mainly alkaline basaltic lavas began to erupt after subalkaline differentiated lavas. The nature of crustal and mantle processes that led to this change in volcanism remains unclear. The Torey Volcanic Field (TVF) of Eastern Transbaikalia (Russia) demonstrates a similar compositional change. Therefore, the TVF is crucial to studying the cause of the difference in geochemical and isotopic signatures of the Mesozoic volcanism in Central and Northeast Asia. TVF belongs to the northeastern end of the Eastern Mongolia Volcanic Area (EMVA). Like other volcanic fields of the EMVA, TVF formed in two stages: early (∼121–129 Ma) and late (∼101–119 Ma). The TVF is composed of subalkaline and alkaline basaltic trachyandesites – trachyandesites. All TVF rocks are characterized by negative Ti and Sr anomalies and positive Ba and Pb anomalies. Compared to the late TVF rocks, the early TVF rocks have distinct negative Ta and Nb anomalies and are highly enriched in light rare earth elements relative to heavy rare earth elements. TVF rocks have the following isotopic characteristics: 87Sr/86Sr(t) = 0.70477–0.70540, εNd(t) = − 0.9 – +2.4, 206Pb/204Pb(t) = 17.9–18.4, and 207Pb/204Pb(t) = 15.5–15.6. However, older rocks mainly have higher εNd(t) values and 206Pb/204Pb(t) and 207Pb/204Pb(t) ratios. Geochemical and isotopic data of samples suggest that the TVF formed by melting in the continental metasomatized lithospheric mantle (CMLM). Phlogopite-amphibole-rutile-bearing pyroxenite veins played a major role in the formation of older rocks. Eclogite, represented by the recycled oceanic crust or the buried lower continental crust, was dominant in the source of younger rocks. The common source for both groups of the TVF rocks was metasomatized hydrous peridotite. Lithospheric extension and subsequent asthenospheric upwelling led to melting in the CMLM and the formation of the TVF. At the early stage of the volcanism, melting occurred at relatively low temperatures where amphibole, phlogopite, and rutile were stable. Due to ongoing lithosphere extension, the melting of eclogite occurred at a higher temperature and/or lower pressure at the late stage of the volcanism. © 2024 Elsevier B.V.

KW - Early Cretaceous

KW - Eastern Mongolia

KW - intraplate volcanism

KW - metasomatized lithospheric mantle

KW - Sr–Nd–Pb isotopes

KW - Transbaikalia

KW - Cretaceous

KW - eclogite

KW - igneous geochemistry

KW - isotopic composition

KW - lead isotope

KW - mantle source

KW - neodymium isotope

KW - pyroxenite

KW - strontium isotope

KW - volcanism

KW - Mongolia

KW - Russian Federation

UR - https://www.mendeley.com/catalogue/01fd764b-98fa-3304-a6ca-6192816e3812/

U2 - 10.1016/j.lithos.2024.107778

DO - 10.1016/j.lithos.2024.107778

M3 - статья

VL - 486-487

JO - Lithos

JF - Lithos

SN - 0024-4937

ER -