South China provenance of the lower-grade Penglai Group north of the Sulu UHP orogenic belt, eastern China: Evidence from detrital zircon ages and Nd-Hf isotopic composition

Abstract

The Dabie-Sulu ultrahigh-pressure orogenic belt resulted from the early Mesozoic collision of the North China block and South China block (comprising the Yangtze and the Cathaysia) and subsequent exhumation of the subducted South China continental slabs. This belt consists of tectonically juxtaposed rock units of different metamorphic grade. Provenance of the low-grade metamorphic terranes exposed along the northern part of the belt can offer useful information about the location of the boundary between these two continental blocks. This study reports detrital zircon ages and Nd-Hf isotopic composition of sedimentary rocks of the low-grade Penglai Group, situated north of the Sulu UHP terrane. Results show that detrital zircon grains mostly crystallized during Mesoproterozoic time, clustering at 1.7 Ga to 1.6 Ga and 1.2 Ga. Nd isotopic composition (T DM value) of the Penglai Group suggests that sedimentary sources are similar to average crustal material of the Yangtze block and mostly formed in Paleo-to Mesoproterozoic. Late Mesoproterozoic detrital zircons probably demonstrate that sedimentary material was derived from the boundary of the Yangtze and Cathaysia blocks, which was formed by the late Mesoproterozoic convergence. Absence of Neoproterozoic detrital zircons from the Penglai sediments probably suggests a late Mesoproterozoic to early Neoproterozoic deposition age (about 1.1 Ga to 0.8 Ga). The age and isotopic evidence implies that the Penglai Group originated from the South China block and probably was thrust onto the basement of the North China block during the early Mesozoic continental collision.

Mesoproterozoic magmatic events in the eastern North China Craton and their tectonic implications: Geochronological evidence from detrital zircons in the Shandong Peninsula and North Korea

“…Besides, the Neoproterozoic Penglai Group in the eastern Shandong Peninsula (Fig. 2; Li et al, 2007) and the Yushulazi Group in the Liaodong Peninsula ( Fig. 1b; Luo et al, 2006) also possess 1.3-1.0 Ga detrital zircon U-Pb ages.…”

Episodic Crustal Extension and Contraction Characterizing the Late Mesozoic Tectonics of East China: Evidence From the Jiaodong Peninsula, East China

“…The Jiaobei domain contains three metamorphic units. From bottom to top: (1) Neoarchean to Paleoproterozoic metagranite, gneissic migmatite, granulite with metamafic or amphibolite lenses; (2) Paleoproterozoic metasedimentary rocks including micaschist, paragneiss, marble, and amphibolite; (3) Neoproterozoic weakly to unmetamorphosed terrigenous rocks (Hacker et al, 2006;X. H. Li et al, 2007;Wan et al, 2006).…”

“…The Jiaobei domain contains three metamorphic units. From bottom to top: (1) Neoarchean to Paleoproterozoic metagranite, gneissic migmatite, granulite with metamafic or amphibolite lenses; (2) Paleoproterozoic metasedimentary rocks including micaschist, paragneiss, marble, and amphibolite; (3) Neoproterozoic weakly to unmetamorphosed terrigenous rocks (Hacker et al., 2006; X. H. Li et al., 2007; Wan et al., 2006). Geochronological works reveal that these rocks have Neoarchean‐Paleoproterozoic protolith ages with peaks at 2.9, 2.7, and 2.5 Ga and experienced a 1.8 Ga amphibolite‐facies metamorphism, belonging to the NCC (Zhai et al., 2000, 2005; S. B. Zhang et al., 2014; G. C. Zhao et al., 1998).…”

Early Triassic potassic volcanism in the Afyon Zone of the Anatolides/Turkey: implications for the rifting of the Neo-Tethys

“…These variations are related to the crystallization history and the U/Th ratio of zircon grain. More details on analytical techniques are given in Wang et al (2006) and Li et al (2007). Values of 207 Pb/ 206 Pb ratio and corresponding ages obtained by the evaporation method are given as weighted average and the errors refer to the 95% confidence level, calculated using the Isoplot/Ex 3.0 program (Ludwig 2003).…”