The Heart of China revisited: II Early Paleozoic (ultra)high‐pressure and (ultra)high‐temperature metamorphic Qinling orogenic collage. Issue 4 (6th August 2013)

• Record Type: Journal Article
• Authors: Bader, Thomas; Franz, Leander; Ratschbacher, Lothar; de Capitani, Christian; Webb, A. Alexander G.; Yang, Zhao; Pfänder, Jörg A.; Hofmann, Mandy; Linnemann, Ulf
• Is Part Of: Tectonics. Volume 32:Issue 4(2013:Jul./Aug.)
• Page Start: 922
• Page End: 947
• Publication Date: 2013-08-06
• Subjects: (ultra)high pressure metamorphism -- (ultra)high temperature metamorphism -- Qinling orogen -- Central China; Geology, Structural -- Periodicals; 551.8
• DOI: 10.1002/tect.20056
• Languages: English
• ISSNs: 0278-7407

Abstract

Abstract : [1] Orogens with multiple (ultra)high‐pressure ((U)HP) and (ultra)high‐temperature ((U)HT) metamorphic events provide a complex but telling record of oceanic and continental interaction. The Early Paleozoic history of the "Heart of China, " the Qinling orogenic collage, offers snapshots of at least three (U)HP and two (U)HT metamorphic events. The preservation of remnants of both oceanic and continental domains together with a ≥110 Myr record of magmatism allows the reconstruction of the processes that resulted in this disparate metamorphism. Herein, we first illuminate the pressure‐temperature‐time (P‐T‐t) evolution of the Early Paleozoic (U)HP and (U)HT events by refining the petrographic descriptions and P‐T estimates, assess published, and employ new U/Th‐Pb zircon, monazite, and titanite, and 40 Ar‐ 39 Ar phengite geochronology to date the magmatic and metamorphic events. Then we explore how the metamorphic and magmatic events are related tectonically and how they elucidate the affinities among the various complexes in the Qinling orogenic collage. We argue that a Meso‐Neoproterozoic crustal fragment—the Qinling complex—localized subduction‐accretion events that involved subduction, oceanic‐arc formation, and back‐arc spreading along its northern margin, and mtantle‐wedge exhumation and spreading‐ridge subduction along its southern margin. Key Points: Qinling‐Qilian tectonic model based on petrology and geochronology Pressure‐temperature‐time evolution of (U)HP and (U)HT rocks Proterozoic Qinling complex localized several subduction‐accretion events