Initiation of the Indosinian Orogeny in South China: Evidence for a Permian Magmatic Arc on Hainan Island

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The University of Chicago Press is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Geology. A B S T R A C TIt has been widely accepted that an active continental margin existed along the coast of Southeast China during the Mesozoic time that produced extensive magmatism in the region. However, there is little constraint as to when this active margin was first initiated. Here we present new SHRIMP U-Pb zircon ages and geochemical and Sr-Nd isotopic data for syntectonic granites on Hainan Island. Our data demonstrate that these rocks, dated at 267-262 Ma, are typical of calc-alkaline I-type granites formed in continental arc environments. The age of this magmatic arc coincides with a sudden change in sedimentary environments in South China during the Permian time, suggesting that the South China Indosinian Orogeny was likely contemporaneous with the onset of continental arc magmatism.

Zircon U-Pb geochronology and heavy mineral composition constraints on the provenance of the middle Miocene deep-water reservoir sedimentary rocks in the Yinggehai-Song Hong Basin, South China Sea

“…9), which may associated to the Grenvillian Orogenic event in this region (Xu et al, 2007b;Li et al, 2008). Representatives of the Indosinian intrusions in Hainan ranging from 280 to 220 Ma (Li et al, 2006;Xie et al, 2006aXie et al, , 2006bWen, 2013;Wen et al, 2013). Cretaceous granitoids and volcanic rocks with ages ranging from 160 to 80 Ma occur in the southern part of the island (Wang et al, 1991(Wang et al, , 2011(Wang et al, , 2015bJia et al, 2009) (Fig.…”

Zircon U–Pb, molybdenite Re–Os and muscovite Ar–Ar isotopic dating of the Xitian W–Sn polymetallic deposit, eastern Hunan Province, South China and its geological significance

“…The flat subduction of the Paleo-Pacific plate beneath the SCB in Mesozoic might have terminated beneath the belt, where there existed contemporaneous bimodal magmatism, diagnostic of the continental arc to intra-arc rift setting due to slab rollback (Jiang et al, 2009 and references therein); (2) The Early Yanshanian granitic magmatism took place only in the Nanling region, with a southeastward-younging trend, in comparison with the distribution of the Late Yanshanian (140-90 Ma) volcanic and intrusive rocks near to the coast (Gilder et al, 1991;Chen and Jahn, 1998;Zhou and Li, 2000;Sun et al, 2003;Wang et al, 2005;Li et al, 2006;Li and Li, 2007;Li et al, 2007a). Li and Li (2007) attributed this younging trend to the slab rollback or high-angle subduction of the Paleo-Pacific plate (Fig.…”

Late Miocene provenance change on the eastern margin of the Yinggehai-Song Hong Basin, South China Sea: Evidence from U–Pb dating and Hf isotope analyses of detrital zircons

“…9, area C). Representative igneous intrusions include the Jianfengling granite (249 Ma), Shilu granite (262 Ma), Panyangdong granite (234 Ma), Changtangling granite (264 Ma), Baolang granite (272 Ma), Tianzai granite (245 Ma) and Zhizhong granite (272 Ma) (Li et al, 2006;Xie et al, 2006aXie et al, , 2006bWen, 2013;Wen et al, 2013). The Yanshanian granitoids are mainly distributed in the southern and western parts of Hainan Island, and their UePb ages are mainly in the range of 170e80 Ma (Wang et al, 1991Jia et al, 2009).…”

“…241 Ma are consistent with those of the Indosinian granites in the South China Block. Also, the Permian (272e254 Ma) and Triassic (249e227 Ma) granitoids which are dominantly shoshonitic-higk-K A-type and I-type granites (Li et al, 2006;Xie et al, 2006a;Wen et al, 2013) have been widely discovered in the Hainan Uplift. The Late PermianeTriassic zircons in our sample have negative ε Hf (t) values of À10.78 to À4.79 with the Mesoproterozoic model ages (Table 2), which are consistent with the ε Hf (t) values (À10 to þ1) in the Hianan Uplift, suggesting they were largely derived from recycling of an old crust.…”