Late Palaeozoic extensional volcanism along the northern margin of Gondwana in southern Turkey: implications for Palaeotethyan development

Autor: Osman Parlak, Timur Ustaömer, Alastair H. F. Robertson
Rok vydání: 2021
Předmět:
Zdroj: Robertson, A H F, Parlak, O & Ustaömer, T 2021, ' Late Palaeozoic extensional volcanism along the northern margin of Gondwana in southern Turkey: implications for Palaeotethyan development ', International Journal of Earth Sciences, vol. 110, no. 6, pp. 1961-1994 . https://doi.org/10.1007/s00531-021-02051-7
ISSN: 1437-3262
1437-3254
DOI: 10.1007/s00531-021-02051-7
Popis: The Late Palaeozoic-Early Mesozoic Tethyan development of the Eastern Mediterranean region remains debatable, especially in Turkey, where alternative northward and southward subduction hypotheses are proposed. Relevant to this debate, new whole-rock geochemical data are provided here for early Carboniferous (Late Tournaisian-Late Visean; c. 340-350 Ma) tuffaceous sedimentary rocks within the cataloturan thrust sheet (Aladag nappe), eastern Taurides. The tuffs accumulated from evolved alkaline volcanism, variably mixed with terrigenous and radiolarian-rich sediments. In addition, Late Palaeozoic meta-volcanic rocks, c. 150 km farther NE, within the Binboga (= Malatya) metamorphics (a low-grade high-pressure unit), are indicative of a within-plate setting. An impersistent geochemical subduction signature in these volcanics may represent an inherited, rather than contemporaneous, subduction influence, mainly because of the absence of a continental margin arc or of arc-derived tuff. Both the Binboga metamorphics and the cataloturan thrust sheet (Aladag nappe) restore generally to the north of the relatively autochthonous Tauride carbonate platform (Geyik Dag), within the carbonate platform bordering north-Gondwana. The cataloturan thrust sheet is interpreted, specifically, as a c. E-W, deep-water, volcanically active rift that progressively infilled. Regional geological evidence suggests that melange units (Konya Complex, Afyon zone), Teke Dere unit, Lycian nappes), and Chios-Karaburun melange, E Aegean) accreted to the north-Gondwana continental margin during the late Carboniferous; this was coupled with localised calc-alkaline granitic magmatism (Afyon zone of Anatolide crustal block). We propose an interpretation in which Late Devonian-Carboniferous alkaline intra-plate volcanism relates to extension/rifting along the north-Gondwana margin. In contrast, the melange accretion and granitic magmatism could relate to short-lived late Carboniferous southward subduction that accompanied the diachronous closure of Palaeotethys. DARIUS project; John Dixon memorial fund; State Key Lab for GPMR Open fund at CUG [GPMR201702]; NSFCNational Natural Science Foundation of China (NSFC) [91755213]; TUBITAK research grantsTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [111R015, 115Y213] We thank the DARIUS project for financial support to carry out the fieldwork in the eastern Taurides (2012-2013) and for covering the cost of the chemical analysis. Yaz Demirtay kindly assisted with diagram preparation. The first author's research (AHFR) on the Carboniferous melange and turbidites was assisted by the John Dixon memorial fund. The second author's research (OP) benefitted from on-going support from the State Key Lab for GPMR Open fund (GPMR201702) at CUG, and NSFC 91755213. The third author's research on the Carboniferous and Triassic units of the central Taurides and the Karaburun Peninsula (TU) was aided by TuBTAK research grants (Nos. 111R015 and 115Y213). The manuscript benefitted from constructive reviews by Prof. Dov Avigad and Prof. O. Candan.
Databáze: OpenAIRE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje