Petrogenesis and tectonic significance of the late Triassic mafic dikes and felsic volcanic rocks in the East Kunlun Orogenic Belt, Northern Tibet Plateau

Abstract

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Geochemistry of silicate melt inclusions in middle and southern Okinawa Trough rocks: Implications for petrogenesis and variable subducted sediment component injection

“…The limited bulk rock compositions of the MOT and SOT make it impossible to determine the evolution and crystallization of the magma, so we have attempted to use compositions of the SMIs to reconstruct the evolution of MOT and SOT basaltic magmas. In Harker diagrams (Figure ), typical first‐order trends are shown in the major element oxide versus MgO diagrams, illustrating the evolution of magma fractional crystallization (Hu et al, ). Content levels of fluid‐mobile element Rb in the SMIs can be used as an indicator of the magma evolution process owing to its incompatibility with all crystallizing minerals (Sun et al, ; Zajacz & Halter, ).…”

Chemical compositions of garnet and clinopyroxene and their genetic significances in Yemaquan skarn iron–copper–zinc deposit, Qimantagh, eastern Kunlun

“…From the Permian to Middle Triassic, abundant granitoids (280 Ma-250 Ma) intruded during this period and were associated with the Paleo-Tethys oceanic basin subducting northward (Deng et al, 2014b;Huang et al, 2014;Li et al, 2001Li et al, , 2013aLi et al, ,2013bMo et al, 2007;QRGST, 1981;Xiong et al, 2013;Yang et al, 1996). The granitoids of Middle Triassic to Early Jurassic indicated the closure of the Paleo-Tethys Ocean and the Eastern Kunlun area entered the intracontinental orogenic stage (Deng et al, 2015b;Guo et al, 1998;Kui et al, 2010;Li et al, 2015c;Mo et al, 2007;Li et al, 2015d;Ding et al, 2015;Hu et al, 2015;Wang et al, 2016). A great number of skarn-type and porphyry-related poly-metallic deposits are temporally and spatially related to Middle to Late Triassic granitic intrusions (235-219 Ma) ( Fig.…”

Geological characteristics, metallogenesis, and tectonic setting of porphyry–skarn Cu deposits in East Kunlun Orogen

“…The regional angular unconformity between the Late Triassic terrestrial Babaoshan (Elashan) Formation and the underlying Early–Middle Triassic shallow marine Naocangjian Formation and the Xilikete Formation (Xia et al, ; Yan et al, ) indicates that the closure of the A'nyemaqen Ocean and continental collision occurred prior to the Late Triassic. Hence, the late Triassic large‐scale granitic magmatism in the EKO generally is associated with syn‐collision or postcollisional processes (Hu et al, ; Shao et al, ; Yan, Wang, Li, Xu, & Deng, ; Yang, Shi, Wu, Wang, & Robinson, ; Yu et al, ). Xiong () summarized the Permian–Triassic granitoids in the EKO and divided them into three stages, that is, the first (270–248 Ma), the second (238–230 Ma), and the third stage (230–185 Ma), representing subduction, syn‐collision, and post–collision extensional settings, respectively.…”

“…The regional angular unconformity between the Late Triassic terrestrial Babaoshan (Elashan) Formation and the underlying Early-Middle Triassic shallow marine Naocangjian Formation and the Xilikete Formation Yan et al, 2008) indicates that the closure of the A'nyemaqen Ocean and continental collision occurred prior to the Late Triassic. Hence, the late Triassic large-scale granitic magmatism in the EKO generally is associated with syn-collision or postcollisional processes (Hu et al, 2016;Shao et al, 2017;Yan, Wang, Li, Xu, & Deng, 2012;Yang, Shi, Wu, Wang, & Robinson, 2009;Yu et al, 2015). Xiong (2014) 2.…”