Počet záznamů: 1
Architecture and composition of ocean floor subducted beneath northern Gondwana during Neoproterozoic to Cambrian: A palinspastic reconstruction based on Ocean Plate Stratigraphy (OPS)
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SYSNO ASEP 0509766 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Architecture and composition of ocean floor subducted beneath northern Gondwana during Neoproterozoic to Cambrian: A palinspastic reconstruction based on Ocean Plate Stratigraphy (OPS) Tvůrce(i) Ackerman, L. (CZ)
Hajná, J. (CZ)
Žák, J. (CZ)
Erban, V. (CZ)
Sláma, Jiří (GLU-S) SAI, RID, ORCID
Polák, Ladislav (GLU-S) ORCID
Kachlík, V. (CZ)
Strnad, L. (CZ)
Trubač, J. (CZ)Zdroj.dok. Gondwana Research. - : Elsevier - ISSN 1342-937X
Roč. 76, December (2019), s. 77-97Poč.str. 21 s. Forma vydání Tištěná - P Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova Accretionary wedge ; Avalonian-Cadomian belt ; Basalt ; Hafnium ; Neodymium ; Ocean Plate Stratigraphy Vědní obor RIV DB - Geologie a mineralogie Obor OECD Geology CEP GA17-15700S GA ČR - Grantová agentura ČR Způsob publikování Omezený přístup Institucionální podpora GLU-S - RVO:67985831 UT WOS 000493799500006 EID SCOPUS 85069815990 DOI 10.1016/j.gr.2019.07.001 Anotace The Blovice accretionary complex, Bohemian Massif, hosts well-preserved basaltic blocks derived from an oceanic plate subducted beneath the northern active margin of Gondwana during late Neoproterozoic to early Cambrian. The major and trace element and Hf–Nd isotope systematics revealed two different suites, tholeiitic and alkaline, whose composition reflects different sources of melts within a back-arc basin setting. The former suite has composition similar to mid-ocean ridge basalts (MORB), yet with striking enrichment in large-ion lithophile elements (LILE) and Pb paralleled by depletion in Nb, in agreement with its derivation from depleted mantle fluxed by subduction-related fluids. In contrast, the latter suite has composition similar to ocean island basalts (OIB) with variable contribution of ancient, recycled crustal material. We argue that both suites represent volcanic members of Ocean Plate Stratigraphy (OPS) and indicate that the oceanic realm consumed by the Cadomian subduction was a complex mosaic of intra-oceanic subduction zones, volcanic island arcs, and back-arc basins with mantle plume impinging the spreading centre. Hence, the basalt geochemistry implies that two distinct domains of oceanic lithosphere may have existed off the Gondwana's continental edge: an outboard domain, made up of old and less buoyant oceanic lithosphere (remnants of the Mirovoi Ocean surrounding former Rodinia?) that was steeply subducted and generated the back-arcs, and young, hot, and more buoyant oceanic lithosphere generated in the back-arcs and later involved in accretionary complexes as dismembered OPS. Perhaps the best recent analogy of this setting is the Izu Bonin–Mariana arc–Philippine Sea in the western Pacific Pracoviště Geologický ústav Kontakt Jana Popelková, popelkova@gli.cas.cz, Sabina Janíčková, Tel.: 233 087 272 Rok sběru 2020 Elektronická adresa https://www.sciencedirect.com/science/article/pii/S1342937X19301637?via%3Dihub
Počet záznamů: 1