Carboniferous – Early Permian magmatic evolution of the Bogda Range (Xinjiang, NW China): Implications for the Late Paleozoic accretionary tectonics of the SW Central Asian Orogenic Belt. (March 2018)

• Record Type: Journal Article
• Authors: Wali, Guzalnur; Wang, Bo; Cluzel, Dominique; Zhong, Linglin
• Is Part Of: Journal of Asian earth sciences. Volume 153(2018)
• Page Start: 238
• Page End: 251
• Publication Date: 2018-03
• Subjects: Bogda Range -- Tianshan (Tien Shan) -- Central Asian Orogenic Belt -- Late Paleozoic -- Accretion tectonics -- Volcanic arc; Earth sciences -- Asia -- Periodicals; Sciences de la terre -- Asie -- Périodiques; Earth sciences; Asia; Periodicals; 555.05
• DOI: 10.1016/j.jseaes.2017.07.045
• Languages: English
• ISSNs: 1367-9120

Abstract

Graphical abstract: Highlights: New age was obtained for Carboniferous - Permian volcanic rocks of the Bogda Range. Volcanic - sedimentary rocks of the Bogda Range contain Precambrian xenolith and detrital zircons. Carboniferous to Early Permian magmatic rocks of the Bogda Range formed in a subduction zone. Abstract: The Late Paleozoic magmatic evolution of the Bogda Range (Chinese North Tianshan) is important for understanding the accretionary history of the Central Asian Orogenic Belt. We investigated the Carboniferous and Lower Permian volcanic and sedimentary sequences of the Daheyan section, southern Bogda Range, and present new zircon U-Pb ages and whole-rock geochemical data for the volcanic rocks. One Carboniferous rhyolite is dated at 298 ± 8 Ma; a Permian basalt yielded many Proterozoic zircon xenocrysts, and its maximum age (∼297 Ma) is constrained by the detrital zircon ages of the sandstone that stratigraphically underlies it. These volcanic rocks belong to calc-alkaline series. We further synthesize previous geochronological, geochemical and isotopic data of magmatic and sedimentary rocks in the Bogda Range. The available data indicate that the magmatism occurred continuously from 350 Ma to 280 Ma. A comprehensive analysis allows us to propose that: (1) the Carboniferous to Early Permian magmatic rocks of the Bogda Range generally show consistent arc-type features; (2) increasing mantle input through time suggests intra-arc extension in a supra-subduction zone; (3) the localized occurrence of Early Permian alkaline pillow basalts and deep water sediments close to the major shear zone advocate a transtensional crustal thinning during the transition from Carboniferous convergence to Early Permian transcurrent tectonics; (4) occurrence of a large number of Proterozoic zircon xenocrysts in the Late Paleozoic magmatic rocks, and Proterozoic detrital zircons in the coeval clastic sediments suggest a continental or transitional basement of the Bogda Arc; (5) subduction in the Bogda area terminated prior to the deposition of Middle Permian terrestrial sediments.