Grenvillian continental collision in south China: New SHRIMP U-Pb zircon results and implications for the configuration of Rodinia

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

“…Our geochemical data are also in contrast to that expected for carbonatite contamination of a plume-related source, which would share highly fractionated Zr/Hf ratios (up to 100) and extremely high LREE contents ( 100 ppm) (e.g., Woodhead et al, 1993;Hastie et al, 2011). Most importantly, there is no geological observation supporting the development of an earliest Neoproterozoic plume in the eastern SCB (e.g., Li et al, 1995Li et al, , 2002Yu et al, 2009;Shu et al, 2011).…”

“…Along the Shuangxiwu domain adjacent to the Jiangshan-Shaoxing Fault system (Figs. 1, 2 and 16), plagiogranite and gabbro in the Zhangshudun ophiolitic suite are dated at 970-910 Ma and the ophiolite is interpreted as forming within a back-arc or intraoceanic arc setting (e.g., Li et al, 1994Li et al, , 2002Li et al, , 2008bGao et al, 2009;Chen et al, 2009a,b). Amphibolite-bearing tonalite and granodiorite within the domain show the geochemical signatures of arc volcanic rocks and give the SHRIMP zircon U-P ages of 915 ± 15 Ma and 905 ± 14 Ma, respectively (Ye et al, 2007).…”

“…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.…”

“…The SCB has been argued to lie within or external to the Rodinia supercontinent in the latest Mesoproterozoic to earliest Neoproterozoic (e.g., Li et al, 1995Li et al, , 2002Zhao and Cawood, 1999;Yang et al, 2004;Yu et al, 2008;Zhao et al, 2011). In the model proposed by others (1995, 2002), the proposed Sibao orogen is considered to range in age from 1.3 Ga to 1.0 Ga and constitutes a collisional orogen equivalent to the Grenville Orogen and is associated with Rodinia assembly.…”

“…The two blocks have been considered to have amalgamated at the end of the Mesoproterozoic to form the Sibao Orogen (inset of Fig. 1) associated with the assembly of Rodinia and to occupy an intracratonic keystone position between Australia and Laurentia (e.g., Li et al, 1995Li et al, , 2002Li et al, , 2008cCharvet et al, 1996;Ye et al, 2007;Boger et al, 2000;Li et al, 2008bLi et al, , 2009). 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).…”