Geochronology, geochemistry, and zircon Hf isotopic compositions of Mesozoic intermediate–felsic intrusions in central Tibet: Petrogenetic and tectonic implications

Underplating of basaltic magmas and crustal growth in a continental arc: Evidence from Late Mesozoic intermediate–felsic intrusive rocks in southern Qiangtang, central Tibet

“…Our new zircon U-Pb age data, together with currently available high-quality zircon U-Pb geochronological data (e.g., Chang et al, 2011;Kapp et al, 2005;Li et al, 2011Li et al, , 2013Li et al, , 2014aLiu et al, 2012Liu et al, , 2014Zhang, 2007;Zhang et al, 2012a), corroborate the presence of a Middle Jurassic-Early Cretaceous continental arc extending ca. 1100 km along the length of southern Qiangtang sub-block from Rotug to Amdo (Fig.…”

“…Mesozoic intermediate-felsic intrusive rocks are widely distributed in the southern Qiangtang, central Tibet (e.g., Kapp et al, 2005;Li et al, 2014a). In this study, we report zircon LA-ICPMS U-Pb age, whole-rock major and trace element, Sr-Nd and zircon Hf isotopic data for Late Jurassic granodiorites and diorites and Early Cretaceous granodiorite porphyries in the Rena Co area, north of Gerze County in southern Qiangtang.…”

“…1b). These rocks are dominated by intermediate-felsic magmatic rocks and currently available geochronological data (e.g., Chang et al, 2011;Guynn et al, 2006;Kapp et al, 2005;Li et al, 2011Li et al, , 2013Li et al, , 2014aLiu et al, 2012Liu et al, , 2014Zhang et al, 2012a) indicate that they were emplaced between 183 and 101 Ma.…”

Middle Jurassic MORB-type gabbro, high-Mg diorite, calc-alkaline diorite and granodiorite in the Ando area, central Tibet: Evidence for a slab roll-back of the Bangong-Nujiang Ocean

“…Li et al, 2014;J.X. Li et al, 2014), the petrogenesis of the Ando MORB-type gabbros and high-Mg diorites could not be explained by a normal oceanic slab subduction.…”

“…The slab roll-back model can well explain the linear distribution of the Jurassic magmatic rocks Liu et al, 2011;Liu, 2012;J.X. Li et al, 2014;Liu et al, 2015).…”