Geochronology and Hf isotopes of zircon from volcanic rocks of the Shuangqiaoshan Group, South China: Implications for the Neoproterozoic tectonic evolution of the eastern Jiangnan orogen

Geochronological, geochemical and Nd–Hf–Os isotopic fingerprinting of an early Neoproterozoic arc–back-arc system in South China and its accretionary assembly along the margin of Rodinia

“…The strongly peraluminous Tiantangshan and Longtang (Yunkai) and Masha (Wuyi) granites were dated at 906 ± 24 Ma (SHRIMP), 901 ± 16 Ma (LA-ICPMS) and 913 ± 11 Ma (SIMS) (e.g., Qin et al, 2006;authors' unpublished data), probably representing the time of crustal anatexis during the closure of the Wuyi-Yunkai intracontinental arc-back-arc basin. Detrital zircons with U-Pb ages of ∼1.0-0.90 Ga (peak age being ∼970 Ma) likely related to the development of the arc-back arc system are abundant in the Neoproterozoic sedimentary rocks along the Wuyi (e.g., Jianning), Nanling (e.g., Zengcheng) and Yunkai (e.g., Xinyi) domains (e.g., Yu et al, 2005Yu et al, , 2007Yu et al, , 2010Wan et al, 2007Wan et al, , 2010Wang et al, 2007cWang et al, , 2008bWang et al, ,c, 2010bLi et al, 2011). Earliest Neoproterozoic (∼1000-900 Ma) inherited grains are commonly identified in the Kwangsian granitic gneiss and Neoproterozoic gneiss with some showing positive ε Hf (t) values (inset of Fig.…”

“…16). Li et al, 1994;12) Gao et al, 2009;13) 14) Ye et al, 2007;15) Chen et al, 2009a;17) Wang et al, 2012a;18) Zhou et al, 2004Zhou et al, , 200919) Zhang et al, 2009;20) Li et al, 2009;21) Ding et al, 2008;22) Zhang et al, 2012c;23) Wang et al, 2008b;24) Shu et al, 2006;25) Li et al, 2010a;26) Hu and Liu, 2002;27) Qin et al, 2006;28) Zhang et al, 1998;29) Zhang et al, 2012a;30) Shu et al, 2008;31) Liu et al, 2001; 32) Shu et al, 2011;33) Li et al, 2005;34) Li et al, 2002;35) Zhang et al, 2011b and 36) this study. Inset (a) shows the early Neoproterozoic tectonic subdivision in the eastern South China Block and associated orogenism.…”

“…However, an interior location within Rodinia does not fit readily with the presence of early Neoproterozoic (∼970-900 Ma) rock units of arc or back-arc basin affinities in the easternmost Yangtze Block (e.g., Shui, 1988;Li et al, , 2008aLi et al, 2006Li et al, , 2009Ye et al, 2007;Gao et al, 2009;Chen et al, 2009a,b;Shu et al, 2011;Cawood et al, 2013). Furthermore, additional age-data suggest that final assembly along the Jiangnan domain did not occur until at least ∼830 Ma (e.g., Wang et al, 2006Wang et al, , 2007bWang et al, , 2008bWang et al, ,c, 2011aWu et al, 2006;Zhou et al, 2004Zhou et al, , 2009Zheng et al, 2007Zheng et al, , 2008Zhao et al, 2011;Zhang et al, 2011cZhang et al, , 2012cZhao and Guo, 2012). As a result, the SCB has either been placed on the margin of Rodinia or external to the supercontinent (e.g., Zhao and Cawood, 1999;Torsvik et al, 2001;Yang et al, 2004).…”

Earliest Neoproterozoic (ca. 1.0Ga) arc–back-arc basin nature along the northern Yunkai Domain of the Cathaysia Block: Geochronological and geochemical evidence from the metabasite

“…The amalgamation process of the Yangtze Block to the northwest and Cathaysia Block to the southeast has been paid much attention due to its important significance for the Precambrian tectonic evolution of the South China Block (SCB) and assembly and breakup of the supercontinent Rodinia (e.g., Li and McCulloch, 1996;Li, 1999;Li et al, 2003aLi et al, ,b, 2008cZhou et al, 2004Zhou et al, , 2009Wang et al, 2006Wang et al, , 2008cWang et al, , 2011aZheng et al, 2006Zheng et al, , 2007Zheng et al, , 2008Zhao et al, 2011). The amalgamation boundary has been accepted as the Jiangshan-Shaoxing suture for the northeast segment (northeast Jiangxi) but probably along the southern margin of the Jiangnan Domain (southwest Jiangxi, western Hunan, northern Guangxi and southern Guizhou Provinces) for the southwest segment (e.g., Zhou and Zhu, 1993;Zhang and Yan, 2005;Li et al, 2008bLi et al, , 2009Wong et al, 2011).…”

Early Cretaceous potassic volcanic rocks in the Jiangnan Orogenic Belt, East China: Crustal melting in response to subduction of the Pacific–Izanagi ridge?

“…Melting of pelitic and granitic sources with high K 2 O concentrations, like those forming the basement to the JOB (Wu et al, 2006b;Wang et al, 2008Wang et al, , 2010Zheng et al, 2008;Yin et al, 2013), occurs through muscovite-and biotite-dehydration and will produce potassium-rich and strongly peraluminous melts (Thompson, 1982;Patiňo Douce et al, 1990;Gardien et al, 1995). Melting of calc-alkaline to tholeiitic basalts will produce low-K to calc-alkaline felsic magmas (Fig.…”