Journal of Earth Science, Vol. 28, No. 2, p. 295–304, April 2017 ISSN 1674-487X Printed in China DOI: 10.1007/s12583-017-0723-y

Detrital Zircon U-Pb Geochronologyof Sinian–Cambrian Strata in the Eastern Guangxi Area, China

Ruxin Ding 1, 2, Heping Zou *1, 2, Kyoungwon Min3, Feng Yin *4, Xiaodong Du1, 2, Xuxuan Ma5, Zhangxin Su1, 2, Wenjie Shen1, 2 1. School of Earth Science and Geological Engineering, Sun Yat-sen University, Guangzhou 510275, China 2. Guangdong Provincial Key Laboratory of Mineral Resources & Geological Processes, Guangzhou 510275, China 3. Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA 4. Exploration Branch Company, SINOPECE , Chengdu 610041, China 5. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China Ruxin Ding: http://orcid.org/0000-0002-1174-5193; Heping Zou: http://orcid.org/orcid.org/0000-0002-4054-7292 Feng Yin: http://orcid.org/orcid.org/g 0000-0001-5914-5034

ABSTRACT: The Eastern Guangxi area locates in the southwestern part of the transition zone between Yangtze and Cathaysia blocks, which is an important region because the boundary between two blocks probablycrosses there. We determined LA-ICPMS U-Pb ages for detrital zircons extracted from three sandstone samples in the Sinian-Cambrian strata in this region. The resulting ages are in the range of the Archeozoic and Neoproterozoic, with three notable concentrates at 991, 974, and 964 Ma, all of which are coeval to the Grenvillian magmatic activity. The new age distribution is siimilar to the data reported in the Precambrian strata of the adjacent southwestern Cathaysia Block, suggesting that most of our detrital zircons are likely derived from the Cathaysia Block. Combined with others’ research, we are more inclined to accept the opinion that there was not an ocean basin between the two blocks dur- ing the Sinian-Cambrian period in Eastern Guangxi area if the timing of collision is thhe Early Neopro- terzoic. But if the timing of collision is the Early Paleozoic, we conclude that Luzhai uplift (i.e., the up- lift between Guilin-Yongfu faultand Lipu fault) beyond the west of Dayaoshan regoin might be one part of southwestern sedimentation boundary of Cathaysia Block and Yangtze Block. We also get a few of detrital zircons with ages of ~590 Ma which probably sourced from northeastern Gondwana and 13 de- trital zircons with over 3 000 Ma U-Pb ages which record the early formation of the earth. KEYWORDS: Cathaysia Block, Yangtze Block, eastern Guangxi area, detrital zircon, U-Pb dating.

0 INTRODUCTION In this research, we collected Sinian–Cambrian sandstone South China Block, one of major blocks in East Asia, in- samples in the Dayaoshan region of Eastern Guangxi area, and cludes Cathaysia Block in the southeast and Yangtze Block in the conducted LA-ICP-MS U-Pb dating for detrital zircons. We northwest. Although the formation of South China Block is criti- hope to obtain new useful evidence to test whether the Paleo- cal in understanding Precambrian tectonics of China, the tiiming zoic residual oceanic basin existed or not, and further discuss of collision and the boundary location in the southwest of South the southwestern border between Cathaysia and Yangtze China Block, are yet to be disputed (Shu, 2012; Zhao, 2012). blocks. Recently, some scholars present that there was a residual oceanic basin in Early Paleozoic between Cathaysia and Yangtze blocks 1 GEOLOGICAL SETTING in the southwest of South China Block through the study of vol- The study area locates between the southwestern part of canic rocks in eastern Guangxi area (Qin et al., 2015, Liu et al., Cathaysia Block and the southeastern part of Yangtze Block 2015; Peng et al., 2015), others scholars put forward that there (Fig. 1). The Yangtze basement consists of Proterozoic and a was still a residual oceanic basin at the end of the Permian in the small amount of Achaean TTGG rocks with the ages in the southwest of South China Block (He et al., 2014). ranges of 3 200–2 900, 2 700–2 400 and 2 100–1 800 Ma (e.g., Qiu et al., 2000; Gao et al., 1999). There are minor 1 700 Ma *Corresponding author: [email protected] (Greentree and Li, 2008) and 1 100–900 Ma igneous rocks and [email protected] extensively distributed Neoproterozoic (840–740 Ma) magmat- © China University of Geosciences and Springer-Verlag Berlin ism around the margin of the Yangtze Block (e.g. Wang et al., Heidelberg 2017 2010a; Zheng et al., 2007; Li et al., 2003b; Zhou et al., 2002; Li, 1999). The Cathaysia basement has been proposed to be of a Manuscript received October 2, 2015. largely Mid-Paleoproterozoic (1 800–2 000 Ma) origin and is Manuscript accepted April 13, 2016. composed dominantly of gneiss, amphibolite and migmatite (Shu et al., 2011; Yu et al., 2010). There are igneous rocks in

Ding, R. X., Zou, H. P., Min, K., et al., 2017. Detrital Zircon U-Pb Geochronology of Sinian–Cambrian Strata in the Eastern Guangxi Area, China. Journal of Earth Science, 28(2): 295–304. doi:10.1007/s12583-017-0723-y. http://en.earth-science.net 296 Ruxin Ding, Heping Zou, Kyoungwon Min, Feng Yin, Xiaodong Du, Xuxuan Ma, Zhangxin Su and Wenjie Shen

Figure 1. Geological sketch map of the study area and sample locations map. (a) The geological map and sample locations (all of white regions stand for strata of post Cambrian); (b) the locations of the researched area between Yangtze Block and Cathaysia Block. the range 1 900–1 700 Ma, 1 400 Ma and 1 000–700 Ma and tact, the Devonian and Carboniferous strata present conforma- are mainly distributed in the northeastern (Wuyishan area) and ble contact, the Carboniferous and Permian strata present con- southwestern (Yunkai area) parts of the Cathaysia Block. After formable or parallel unconformable contact (Yin, 1997). The the period at ca. 825 Ma, rift basins were formed in South Chi- Jurassic, Cretaceous and Paleogene strata, corresponding to na Block (Feng et al., 2016; Shu, 2006; Li et al., 2003a, b). The terrestrial facies, are sporadically scattered in the study area. basement rocks of the Yangtze and Cathaysia blocks are un- Most of the granitic plutons in the study area were emplaced conformably overlain in turn by the Upper Neoproterozoic– during Yanshanian periods and few of them were emplaced Lower Paleozoic, Devonian–Lower Triassic and Upper during Indosinian or Caledonian. The Sinian–Cambrian and Triassic–Lower Jurassic strata (e.g., Wang et al., 2014; Shu et Devonian–Permian strata occurred regional folding. In the al., 2011; Wan et al., 2010; Yu et al., 2010). During the Later researched area, the fault strike is mainly NNE-NE with partial Neoproterozoic (Ediacaran or Sinian)–Cambrian, most of NW or close to SN. The fault experienced the multiphased Yangtze Block was covered by carbonate platform system (Xu overprinting. et al, 2012; Jiang et al., 2011); meanwhile the Cathaysia Block was broken up into three sub-blocks, namely, the Wuyi, South 2 SAMPLING Jiangxi-Nanling and Yunkai, which were separated from one Figure 1 shows sampling locations. Figure 2 shows another by intracontinental rift zones (Yao et al., 2011; Shu, field pictures of sample locations and photomicrographs of 2006). The intracontinental rift basins in the Cathaysia Block samples. Sample 712-10 (N24°54.487′, E112°01.292′) is col- were mainly covered by clastic rocks (Zhou et al., 2016; Shu, lected from a meta-siltstone layer in the Sinian stratum in 2006; Guangdong BGMR, 1988; Hunan BGMR, 1988; Gua- Mashi Town, Jianghua County, Hunan Province. Sample ngxi BGMR, 1985; Jiangxi BGMR, 1985). 802-1 (N23°45.257′, E110°39.170′) from the Cambrian sand- The exposed strata of this study area are Sinian stone is taken from near the national highway 321 in –Cambrian, Devonian–Permian, Jurassic, Cretaceous and Pa- Dongrong Town, Teng County, Guangxi Province. Sample leogene sequences. The Sinian–Cambrian strata are conforma- 802-6 (N24°06.195′, E110°35.490′) is a Cambrian sandstone ble in sequence and composed mainly of clastic rocks. The near the national highway 321, ~500 m in the north of Hua- pre-Devonian and Devonian strata present unconformable con- ngcun town, Mengshan County, Guangxi Province.

Detrital Zircon U-Pb Geochronologyof Sinian–Cambrian Strata in the Eastern Guangxi Area, China 297

Figure 2. Field pictures of sample locations (left) and photomicrographs of samples (right).

3 ANALYTICAL PROCEDURES were performed at the State Key Laboratory of Geological We followed a standard mineral separation procedure in- Processes and Mineral Resources, China University of Geos- cluding crushing, hand washing, magnetic separation, sepa- ciences (Wuhan). rated by alcohol or heavy liquid, selection under microscope, then random selection of zircon grains under binocular, stick- 4 RESULTS ing grains into target and fixing it by epoxy resin, polishing it In this study, we examined internal structures of 110 by polish plate. The selected zircon grains were examined zircons for Sample 712-10, 106 zircons for Sample 802-1 and with JXA-8100 EPMA and each grain’s CL (cathodolumi- 113 zircons for Sample 802-6. Most of these zircons are hy- nescence) images were taken. In-situ U-Pb dating was con- pidiomorphic to idiomorphic with linear dimensions of ducted using Agilent 7500a LA-ICPMS with a laser ablation 50–260 μm (sample 712-10), 100–300 μm (802-1), and system of GeoLas 2005. The diameter of the laser beam spot is 100–400 μm (802-6), respectively. Zircon grains are colorless 32 μm. The external standard sample of element content adopts to light pink and are euhedral tosubhedral crystals or crystal NIST SRM 610 and the internal standard adopts 29Si. The fragments. A few grains are subrounded to rounded crystals isotope ratios standard sample adopts 91500 and GJ-1. In the with pitted surfaces (Fig. 3). The euhedral-subhedral grains dating process, 5 to 6 zircon grains are dated every 91500 suggest little sedimentary transport, whereas the rounded dating twice. The original data were processed by ICPMSDa- grains suggest input of material that underwent prolonged and taCal (Liu et al., 2008). The U-Pb concordia diagram was possibly multicycle transport. Most of the zircons have clear generated using Isoplot 3.75 (Ludwig, 2012). The U-Pb dating evidence of oscillatory zoning (Fig. 3). It is generally

298 Ruxin Ding, Heping Zou, Kyoungwon Min, Feng Yin, Xiaodong Du, Xuxuan Ma, Zhangxin Su and Wenjie Shen

Figure 3. Representative CL images. Circles stand for the analysis spots and numbers stand for U-Pb ages (Ma). (a), (b), (c) stand for sample 712-10, 802-1, 802-6, respectively.

Detrital Zircon U-Pb Geochronologyof Sinian–Cambrian Strata in the Eastern Guangxi Area, China 299 considered that Th/U ratio for the magmatic zircon is greater Figure 5 shows the U-Pb age distributions for three sam- than 0.2 whereas the metamorphic zircons have Th/U ratios of ples. The U-Pb ages are concentrated in four groups: 514–618, <0.10 (Rubatto, 2002; Hoskin and Schaltegger, 2003). The 631–1 278, 1 306–2 047, 2 131–2 886 and >3000 Ma. The majority of our grains yielded Th/U greater than 0.2, indicat- three samples yield three most prominent peaks at 991, 964 and ing a magmatic origin. 974 Ma. The age pattern corresponds to the timing of Grenvil- Most of the U-Pb ages are concordant (Fig. 4). Because lian magmatic activities, and possibly marked the formation of 207Pb/206Pb ages are commonly considered to be more reliable Rodinia supercontinent (Li et al., 2008). The period of 514–618 than 206Pb/238U ages for older zircons with the age of more than Ma can correspond to Pan-Africa movement and 1 306–2 047 1 000 Ma (Compston et al., 1992), 207Pb/206Pb ages for samples Ma roughly correspond to the formation of Columbia super- are used. For young grains with 206U/238Pb ages<1 000 Ma, we continent (Zhao et al., 2004; Rogers and Santosh, 2009). The used their 206U/238Pb ages for further discussion. age group of 2 131–2 886 Ma is probably related to the forma- tion of the Kenorland supercontinent (Pesonen et al, 2003). The oldest age group (>3 000 Ma) is composed of relatively small number of zircons, but they recorded the early formation of the Earth.

5 DISCUSSIONS 5.1 The Identification of Provenance Areas To identify provenances of the Sinian–Cambrian strata, we compared the new zircon ages with published geochronologic data from the nearby areas, including the Precambrian strata of southeastern Yangtze Block and southwestern Cathaysia Block (Fig. 5). The U-Pb ages obtained from detrital zircons in the Neoproterozoic sedimentary rocks of southeastern Yangtze Block concentrate on Jinningian Period (ca. 800 Ma). The age peak is at 819 Ma, which is within the range reported from various rocks in Yangtze Block (800–850 Ma; Wang et al., 2010a). This period corresponds to the breakup of the Rodinia continent (Li et al., 2003a, b). The U-Pb ages of the detrital zircons in the Neoproterozoic sedimentary rocks of southwes- tern Cathaysia Block are grouped on the Grenvillian Period (ca. 1000 Ma), with the peak at 956 Ma. This suggests that a large scale magmatic activity occurred in Cathaysia Block in the Grenvillian Period, or Cathaysia Block was very close to a Grenvillian orogen (Wang et al, 2008). In fact, recent study showed that granitic gneisses from the Wuyi-Yunkai domain in Cathaysia Block gave zircon U-Pb ages of 985–913 Ma, indi- cating the presence of the Early Neoproterozoic granitic mag- matism in the Cathaysia interior (Wang et al., 2014). The morphological characteristics of most of our analyzed detrital zircons from the Sinian–Cambrian sandstone samples favor a shorter transport distance. In addition, the paleocurrent data of lower Paleozoic strata in South China Block showed a W‐NNW orientated transport direction from Cathaysia Block across to the central Yangtze Block (Wang et al, 2010b). These data suggest that the source lay to the southeast, either within the southeastern Cathaysia Block or beyond the current margins of the block. Since numerous Paleoproterozoic and Neoprote- rozoic igneous rocks exposed in the Wuyishan and Yunkaida- shan domains of Cathaysia Block (e.g., Li et al., 2014; Wang et al., 2014; Wan et al., 2010, 2007; Shu, et al., 2008), Cathaysia Block is of a suitable age to supply the Paleoproterozoic and Neoproterozoic grains of the analyzed Sinian–Cambrian sam- ples. In Cathaysia Block, there are age distributions from Arc- heozoic to Neoproterozoic Period and peaks around 1 700–1 800 Ma and 2 500 Ma. This phenomenon shows that Figure 4. The 207Pb／235U–206Pb／238U concordia plots. magmatic thermal events occurred in the same period and were

300 Ruxin Ding, Heping Zou, Kyoungwon Min, Feng Yin, Xiaodong Du, Xuxuan Ma, Zhangxin Su and Wenjie Shen recorded by Yangtze Block. The Sinian–Cambrian strata of and paleontological data, it was suggested that during the Neo- Yangtze Block are mainly composed of carbonates but those of proterozoic and Early Paleozoic, South China Block lay along Cathaysia Block are mainly composed of clastic rocks. This the northern margin of Gondwana (Zhao and Cawood, 2012). means that detritus could not extend readily across the margin Recent work of provenance data in combination with general of Yangtze Block because of the intervening carbonate plat- geological information has suggested that South China Block form. was located at the nexus between India, Antarctica, and Aus- Until now, igneous rocks with ages of ~2 490 Ma and tralia, along the northern margin of East Gondwana during the ~590 Ma have not yet been found in Cathaysia Block. However, Cambrian (Xu et al., 2013, 2014; Cawood et al., 2013), so a there are metavolcanic rocks which chemically fall into tra- few of our detrital zircons with ages of ~2 500 Ma and ~590 chyandesitic and rhyolitic sections with U-Pb zircon age of 527 Ma probably came from this portion of northeast Gondwana. Ma existed in Tunchang, Hainan Island (Ding et al., 2002). The Therefore, the main evidence to identify the provenances ages of 537 Ma to 507 Ma found in Guzhai pluton located in of Sinian–Cambrian sedimentary rocks is which provides the eastern Guangdong province are interpreted as the Cambrian ages of the detrital zircons, Grenvillian Period (ca. 1 000 Ma) magmatic event (Ding et al., 2005). Also, Chen et al. (2009) or Jinning Period (ca. 800 Ma). It is apparently shown that the argued for the existence of a magmatic or thermal event exis- U-Pb ages of the three sample detrital zircons are consistent tent in South China Block during the Cambrian time (ca. 526 with the ages of the detrital zircons in the Precambrian strata of Ma). On the other hand, according to geochemical, provenance, southwestern Cathaysia Block. This shows that most of the

Figure 5. The comparison between the U-Pb age patterns of the detrital zircon in this study and the published data in southeastern Yangtze Block and south- western Cathaysia Block. (a), (b), (c) are the U-Pb age patterns of 712-10, 802-1 and 802-6, respectively; (d) is the U-Pb age pattern of total our three samples; (e) and (f) are the U-Pb age patterns of southeastern Yangtze Block and southwestern Cathaysia Block, respectively. The age data of the southeastern Yangtze Block is from Wang et al. (2012, 2010a), Wang and Zhou (2012). The age data of the southwestern Cathaysia Block is from Yu et al. (2010, 2008), Wang et al. (2008).

Detrital Zircon U-Pb Geochronologyof Sinian–Cambrian Strata in the Eastern Guangxi Area, China 301

Figure 6. The isopach map of the Nanhua–Cambrian strata in Eastern Guangxi area. detrital zircons in our three samples probably come from the But if the timing of collision is the Early Paleozoic (e.g., Qin et Cathaysia Block, and a few of the detrital zircons with ages of al., 2015), we can say that Luzhai uplift beyond the west of ~2 500 and ~590 Ma probably have some relationship with Dayaoshan region might be one part of southwestern sedimen- Gondwana. tation boundary of Cathaysia Block and Yangtze Block.

5.2 Constraints on the Yangtze-Cathaysian Boundary 5.3 Identification of Old Zircons (>3 000 Ma) We acquire the Nanhua–Cambrian overall thickness con- Among the 328 zircon grains in this study, thirteen yielded tour map (Fig. 6) by Kriging interpolation based on the many U-Pb ages of older than 3 000 Ma (Appendix Table 1). They locations’ thickness measurement (Chen et al., 2006). Seen have (1) Th/U ratios are between 0.17 and 0.78, and (2) oscil- from the figure, there are two sedimentary centers which sedi- latory zones suggesting the magmatic origin of these zircon mentary thicknesses are up to 4 000 m, even 6 000 m. grains. One sedimentary center locates to the north of Guilin- Twelve ages (between 3 018–3 639 Ma) with over 90% Yongfu faultwhere sediments are mainly carbonate rocks. By concordance are selected for statistical analysis (Fig. 7a) with this center, the samples from Nanhua stratum by Wang and those published U-Pb age data over 3 000 Ma of detrital zircons Zhou (2012) and Sinian–Cambrian stratum by Wang et al. from the Cambrian and Precambrian strata in Cathaysia Block (2013) have shown their provenances are from Yangtze Block. (Wang P M et al., 2012; Li et al., 2009;Yu et al., 2008, 2007; The other sedimentary center locates to the south of Lipu fault Wan et al., 2007). The results show a very weak supply be- where sediments are mainly clastic rocks (Chen et al., 2006). tween 3 000–3 300 Ma (Fig. 7a). We also analyzed statistically Our samples locate by this clastic sedimentary center, which (Fig. 7b) the published U-Pb age data over 3 000 Ma of detrital shows their provenance is Cathaysia Block. In addition, Wang zircons from the Cambrian and Precambrian strata in Yangtze et al. (2013) acquired some samples from the Sinian–Cambrian Block (Chen et al., 2013; Wang L J et al., 2012; Xiao, 2012; stratum in Jinjiling Mountain which also shows sediments Gao et al., 2011; Zhao et al., 2010; Jiao et al., 2009; Liu et al., come from the Cathaysia Block. 2006; Zhang et al., 2006), the results show a cluster of Based on the thickness contour map and all the samples’ 3200–3300 Ma (Fig. 7b). Furthermore, the published U-Pb age locations relatively arranging on both sides, we present that data over 3 000 Ma of detrital zircons from Permian and older Luzhai uplift (i.e., the uplift between Guilin-Yongfu fault and strata in South China Block (Chen et al., 2013; Li et al., 2012, Lipu fault and with few Nanhua–Cambrian sediment) is a very 2009; Wang P M et al., 2012; Wang L J et al., 2012; Wang Y J important area. If the timing of collision is the Early Neopro- et al., 2010; Xiao, 2012; Xu et al., 2012; Yao et al., 2012, 2011; terzoic, we are more inclined to accept the opinion that there Gao et al., 2011; Xiang and Shu, 2010; Zhao et al., 2010; Jiao was not an ocean basin between the two blocks during the et al., 2009; Yu et al., 2008, 2007; Wan et al., 2007; Liu et al., Sinian–Cambrian Period (Shu, 2012, 2006; Wang et al., 2010b). 2006; Zhang et al., 2006), the results also shows a cluster of

302 Ruxin Ding, Heping Zou, Kyoungwon Min, Feng Yin, Xiaodong Du, Xuxuan Ma, Zhangxin Su and Wenjie Shen

3 200–3 300 Ma (Fig. 7c). All of the three results show that Sinian–Cambrian period if the timing of collision is the Early there maybe occurred some magmatic thermal events before Neoproterzoic. But if the timing of collision is the Early Pa- 3 000 Ma. The summit period maybe is between 3 200–3 300 leozoic, we present that Luzhai uplift beyond the west of Ma. As mentioned before, most of the detrital zircons in our Dayaoshan regionmight be one part of southwestern sedimen- three samples probably come from Cathaysia Block. However, tation boundary of Cathaysia Block and Yangtze Block. we cannot make sure that the magmatic thermal events before (3) We get 13 detrital zircons acquired with over 3 000 3 000 Ma occurred in Cathaysia Block since the grains might Ma U-Pb ages. This shows that there occurred some magmatic be repeatedly transported or transported from an exotic Arc- thermal events before 3 000 Ma. Combining with the former hean continent (probably from Gondwana). studies we think the summit of these thermal events maybe is ca. 3 200–3 300 Ma. But we cannot make sure that the mag- 6 CONCLUSIONS matic thermal events before 3 000 Ma occurred in Cathaysia (1) The detrital zircons LA-ICPMS U-Pb age spectrum of Block since the grains might be repeatedly transported or 3 Sinian–Cambrian sandstone samples in the Eastern Guangxi transported from an exotic Archean continent. area have the most notable age summits being 991, 974, and 964 Ma. These summits are similar to the summit of detrital zir- ACKNOWLEDGMENTS cons U-Pb age in the Precambrian strata of the adjacent southwest This study was jointly supported by the National Natural Cathaysia Block, which means most of the studied three sample Science Foundation of China (No. 41102131), the Fundamental detrital zircons probably come from Cathaysia Block. Research Funds for the Central Universities of China (No. (2) We are more inclined to accept the opinion that there 12lgpy22), Guangdong Natural Science Foundation (No. was not an ocean basin between the two blocks during the 2015A030313193), China Geological Survey (No. 1212011121064), Chinese Association for science and technology project (No. 2014XSJLW01-02) and China Scholarship Council. We are grateful to Shi’ai Chen, Miaoji Lao and Gang Yang for their assistance in field work. The final publication is available at Sprin- ger via http://dx.doi.org/10.1007/s12583-017-0723-y.

Electronic Supplementary Material: Supplementary material (Appendix Table 1) is available in the online version of this article at http://dx.doi.org/10.1007/s12583-017-0723-y.

REFERENCES CITED Cawood, P. A., Wang, Y. J., Xu, Y. J., et al., 2013. Locating South China in Rodi- nia and Gondwana: A Fragment of Greater India Lithosphere? Geology, 41(8): 903–906. doi:10.1130/g34395.1 Chen, D. Z., Wang, J. G., Qing, H. R., et al., 2009. Hydrothermal Venting Activi- ties in the Early Cambrian, South China: Petrological, Geochronological and Stable Isotopic Constraints. Chemical Geology, 258(3–4): 168–181. doi:10.1016/j.chemgeo.2008.10.016 Chen, K., Gao, S., Wu, Y. B., et al., 2013. 2.6–2.7 Ga Crustal Growth in Yangtze Craton, South China. Precambrian Research, 224: 472–490. doi:10.1016/j.precamres.2012.10.017 Chen, M. H., Liang, J. C., Zhang, G. L., et al., 2006. Lithofacies Paleogeographic Constraints of Southwestern Boundary between Yangtze and Cathaysian Plates in Caledonian. Geological Journal of China Universities, 12(1): 111–122 (in Chinese with English Abstract) Compston, W., Williams, I. S., Kirschvink, J. L., et al., 1992. Zircon U-Pb Ages for the Early Cambrian Time-Scale. Journal of the Geological Society of London, 149(2): 171–184. doi:10.1144/gsjgs.149.2.0171 Ding, S. J., Xu, C. H., Long, W. G., et al., 2002. Tectonic Attribute and Geochro- nology of Meta-Volcanic Rocks, Techang, Hainan Island. Acta Petrolo-

gica Sinica, 18(1): 83–90 Figure 7. The pattern for detrital zircon U-Pb ages of over 3 000 Ma from Ding, X., Zhou, X. M., Sun, T., 2005. The Episodic Growth of the Continental the Cathaysia (a), Yangtze (b) and South China Block (c), respectively Crustal Basement in South China: Single Zircon LA-ICPMS U-Pb Dating (a)U-Pb age data over 3 000 Ma distribution of detrital zircons from the of Guzhai Granodiorite in Guangdong. Geological Review, 51(4): Cambrian and Precambrian strata in Cathaysia Block; (b)U-Pb age data over 382–392 3 000 Ma distribution of detrital zircons from the Cambrian and Precam- Feng, L. J., Zhang, Q. R., 2016. The Pre-Sturtian Negative δ13C Excursion of the brian strata in Yangtze Block; (c) U-Pb age data over 3 000 Ma distribution Dajiangbian Formation Deposited on the Western Margin of Cathaysia of detrital zircons from the Permian and earlier strata in South China Block.

Detrital Zircon U-Pb Geochronologyof Sinian–Cambrian Strata in the Eastern Guangxi Area, China 303

Block in South China. Journal of Earth Science, 27(2): 225–232 43–57. doi:10.1016/s0301-9268(99)00020-0 Gao, S., Yang, J., Zhou, L., et al., 2011. Age and Growth of the Archean Kongling Li, Z. X., Bogdanova, S. V., Collins, A. S., et al., 2008. Assembly, Configuration, Terrain, South China, with Emphasis on 3.3 Ga Granitoid Gneisses, and Break-Up History of Rodinia: A Synthesis. Precambrian Research, American Journal of Science, 311(2): 153–182. doi:10.2475/02.2011.03 160(1–2): 179–210. doi:10.1016/j.precamres.2007.04.021 Gao, S., Luo, T. C., Zhang, B. R., et al., 1999. Structure and Composition of the Li, Z. X., Li, X. H., Kinny, P. D., et al., 2003. Geochronology of Neoproterozoic Continental Crust in East China．Science in China (Series D): Earth Science, Syn-Rift Magmatism in the Yangtze Craton, South China and Correlations 42(2): 129–140. doi:10.1007/bf02878511 with Other Continents: Evidence for a Mantle Superplume that Broke up Guangdong BGMR (Bureau of Geology and Mineral Resources of Guangdong Rodinia. Precambrian Research, 122(1–4): 85–109. Province), 1988. Regional Geology of the Guangdong Province. Geological doi:10.1016/s0301-9268(02)00208-5 Publishing House, Beijing. 941 (in Chinese with English Abstract) Liu, S. F., Peng, S. B., Lin, M. S., 2015. The Discovery and Implication of Early Guangxi BGMR (Bureau of Geology and Mineral Resources of Guangxi Zhuang Paleozoic Ophiolite in Nuodong, Cenxi, Northwestern Yunkai Uplift. An- Autonomous Region), 1985. Regional Geology of the Guangxi Zhuang Au- nual Meeting of the Geoscience of China. (in Chinese) tonomous Region. Geological Publishing House, Beijing. 853 (in Chinese Liu, X. M., Gao, S., Ling, W. L., et al., 2006. Identification of 3.5 Ga Detrital with English Abstract) Zircons from Yangtze Craton in South China and the Implication for Arc- Greentree, M. R., Li, Z. X., 2008. The Oldest Known Rocks in South Western hean Crust Evolution. Progress in Natural Science, 16(6): 663–666. China: SHRIMP U-Pb Magmatic Crystallisation Age and Detrital Prove- doi:10.1080/10020070612330050 nance Analysis of the Paleoproterozoic Dahongshan Group. Journal of Liu, Y. S., Hu, Z. C., Gao, S., et al., 2008. In Situ Analysis of Major and Trace Asian Earth Science, 33(5–6): 289–302. doi:10.1016/j.jseaes.2008.01.001 Elements of an Hydrous Minerals by LA-ICP-MS without Applying an In- He, W. H., Tang, T. T., Yue, M. L., et al., 2014. Sedimentary and Tectonic Evolu- ternal Standard. Chemical Geology, 257(1–2): 34–43. tion of Nanhuan–Permian in South China. Earth Science—Journal of China doi:10.1016/j.chemgeo.2008.08.004 University of Geosciences, 39(8): 929–953 (in Chinese with English Ab- Ludwig, K. R., 2012. Isoplot／Ex Version 3.7. A Geochronological Toolkit for stract) Microsoft Excel. Berkeley: Berkeley Geochronology Center Special Publi- Hoskin, P. W. O., Schaltegger, U., 2003. The Composition of Zircon and Igneous cation, 5: 1–75 and Metamorphic Petrogenesis. In: Hanchar, J. M., Hoskin, P. W. O. eds., Peng, S. B., Liu, S. F., Lin, M. S., et al., 2015. The Discovery of Early Paleozoic Zircon. Reviews in Mineralogy & Geochemistry, 53(1): 27–62. High Magnesium-Magnesia Basaltic Andesite-Andesite (Sanukite) Dacite: doi:10.2113/0530027 the New Evidence of Caledonian Ocean-Continent Subduction in Norhwes- Hunan BGMR (Bureau of Geology and Mineral Resources of Hunan Province), tern Yunkai Uplift. Annual Meeting of the Geoscience of China. (in Chi- 1988. Regional Geology of the Hunan Province. Geological Publishing nese) House, Beijing. 719 (in Chinese with English Abstract) Pesonen, L. J., Elming, S., Mertanen, S., et al., 2003. Palaeomagnetic Configura- Jiang, G. Q., Shi, X. Y., Zhang, S. H., et al., 2011. Stratigraphy and Paleogeogra- tion of Continents during the Proterozoic. Tectonophysics, 375(1–4): phy of the Ediacaran Doushantuo Formation (ca. 635–551 Ma) in South 289–324. doi:10.1016/s0040-1951(03)00343-3 China. Gondwana Research, 19(4): 831–849. doi:10.1016/j.gr.2011.01.006 Qin, X. F., Wang, Z. Q., Wang, T., et al. 2015.The Reconfirmation of Age and Jiangxi BGMR (Bureau of Geology and Mineral Resources of Jiangxi Province), Tectonic Setting of the Volcanic Rocks of Yingyangguan Group in the 1985. Regional Geology of the Jiangxi Province. Geological Publishing Eastern Guangxi: Constraints on the Structural Pattern of the Southwestern House, Beijing. 921 (in Chinese with English Abstract) Segment of Qinzhou-Hangzhou Joint Belt. Acta Geoscientica Sinica, 36(3): Jiao, W. F., Wu, Y. B., Yang, S. H., et al., 2009. The Oldest Basement Rock in 283–292 (in Chinese with English Abstract) the Yangtze Craton Revealed by Zircon U-Pb Age and Hf Isotope Composi- Qiu, Y. M., Gao, S., McNaughton, N. J., et al., 2000. First Evidence of ＞3.2 Ga tion. Science China: Earth Sciences, 52(9): 1393–1399. Continental Crust in the Yangtze Craton of South and Its Implications for doi:10.1007/s11430-009-0135-7 Archean Crustal Evolution and Phanerozoic Tectonics. Geology, 28(1): Li, Q., Duan, R. C., Ling, W., et al., 2009. Detrital Zircon U-Pb Geochronology 11–14. doi:10.1130/0091-7613(2000)028<0011:feogcc>2.3.co;2 of the Early Paleozoic Strata in Eastern Guangxi and Its Constraint on the Rogers, J. J. W., Santosh, M., 2009. Tectonics and Surface Effects of the Super- Caledonian Tectonic Nature of the Cathaysian Continental Block. Earth continent Columbia. Gondwana Research, 15(3–4): 373–380. Science—Journal of China University of Geosciences, 34(1): 189–202 (in doi:10.1016/j.gr.2008.06.008 Chinese with English Abstract) Rubatto, D., 2002. Zircon Trace Element Geochemistry: Partitioning with Garnet Li, X. H., Li, Z. X., Li, W. X., 2014. Detrital Zircon U-Pb Age and Hf Isotope and the Link between U-Pb Ages and Metamorphism. Chemical Geology, Constrains on the Generation and Reworking of Precambrian Continental 184(1–2): 123–138. doi:10.1016/s0009-2541(01)00355-2 Crust in the Cathaysia Block, South China: A Synthesis. Gondwana Re- Shu, L. S., 2012. An Analysis of Principal Features of Tectonic Evolution in search, 25(3): 1202–1215 South China Block. Geological Bulletin of China, 31(7): 1035–1053 (in Li, X. H., Li, Z. X., Ge, W., et al., 2003a. Neoproterozoic Granitoids in South Chinese with English Abstract) China: Crustal Melting above a Mantle Plume at ca. 825 Ma? Precambrian Shu, L. S., Deng, P., Yu, J. H., et al., 2008. The Age and Tectonic Environment Research, 122(1–4): 45–83. doi:10.1016/s0301-9268(02)00207-3 of the Rhyolitic Rocks on the Western Side of Wuyi Mountain, South China. Li, X. H., Li, Z. X., He, B., et al., 2012. The Early Permian Active Continental Science in China D: Earth Science, 51(8): 1053–1063 (in Chinese with Eng- Margin and Crustal Growth of the Cathaysia Block: In-Situ U-Pb, Lu-Hf lish Abstract) and O Isotope Analyses of Detrital Zircons. Chemical Geology, 328(11): Shu, L. S., Faure, M., Yu, J. H., et al., 2011. Geochronological and Geochemical 195–207. doi:10.1016/j.chemgeo.2011.10.027 Features of the Cathaysia Block (South China): New Evidence for the Neo- Li, X. H., 1999. U-Pb Zircon Ages of Granites from the Southern Margin of the proterozoic Breakup of Rodinia. Precambrian Research, 187(3–4): 263–276. Yangtze Block: Timing of Neoproterozoic Jinning Orogeny in SE China doi:10.1016/j.precamres.2011.03.003 and Implications for Rodinia Assembly. Precambrian Research, 97(1–2): Shu, L. S., 2006. Predevonian Tectonic Evolution of South China: From Cathay-

304 Ruxin Ding, Heping Zou, Kyoungwon Min, Feng Yin, Xiaodong Du, Xuxuan Ma, Zhangxin Su and Wenjie Shen

sia Block to Caledonian Period Folded Orogenic Belt. Geological Journal of Xu, Y. J., Cawood, P. A., Du, Y. S., et al., 2014. Early Paleozoic Orogenesis China Universities, 12(4): 418–431 (in Chinese with English Abstract) along Gondwana’s Northern Margin Constrained by Provenance Data from Wan, Y. S., Liu, D. Y., Wilde, S. A. et al., 2010. Evolution of the Yunkai Terrane, South China, Tectonophysics, 636: 40–51 South China: Evidence from SHRIMP Zircon U-Pb Dating, Geochemistry Xu, Y. J., Cawood, P. A., Du, Y. S., et al., 2013. Linking South China to North- and Nd Isotope. Journal of Asian Earth Science, 37(2):140–153. ern Australia and India on the Margin of Gondwana: Constraints from De- doi:10.1016/j.jseaes.2009.08.002 trital Zircon U-Pb and Hf Isotopes in Cambrian Strata. Tectonics, 32(6): Wan, Y. S., Liu, D. Y., Xu, M. H., et al., 2007. SHRIMP U-Pb Zircon Geochro- 1547–1558. doi:10.1016/j.tecto.2014.08.022 nology and Geochemistry of Metavolcanic and Metasedimentary Rocks in Xu, Y. J., Du, Y. S., Cawood, P. A., et al., 2012. Detrital Zircon Provenance of Northwestern Fujian, Cathaysia Block, China: Tectonic Implications and the Upper Ordovician and Silurian Strata in the Northeastern Yangtze Block: Need to Redefine Lithostratigraphic Units. Gondwana Research, 12(1–2): Response to Orogenesis in South China. Sedimentary Geology, 267–268: 166–183. doi:10.1016/j.gr.2006.10.016 63–72. doi:10.1002/tect.20099 Wang, L. J., Griffin, W. L., Yu, J. H., et al., 2010. Precambrian Crustal Evolution Yao, J. L., Shu, L. S., Santosh, M., et al., 2012. Precambrian Crustal Evolution of of the Yangtze Block Tracked by Detrital Zircons from Neoproterozoic Se- the South China Block and Its Relation to Supercontinent History: Con- dimentary Rocks. Precambrian Research, 177(1–2): 131–144. straints from U-Pb Ages, Lu-Hf Isotopes and REE Geochemistry of Zircons doi:10.1016/j.precamres.2009.11.008 from Sandstones and Granodiorite, Precambrian Research, 208–211(7): Wang, L. J., Yu, J. H., Griffin, W. L., et al., 2012a. Early Crustal Evolution in the 19–48. doi:10.1016/j.precamres.2012.03.009 Western Yangtze Block: Evidence from U-Pb and Lu-Hf Isotopes on Detrit- Yao, J. L., Shu, L. S., Santosh, M., 2011. Detrital Zircon U-Pb Geochronology, al Zircons from Sedimentary Rocks. Precambrian Research, 222–223: Hf-Isotopes and Geochemistry—New Clues for the Precambrian Crustal 368–385. doi:10.1016/j.precamres.2011.08.001 Evolution of Cathaysia Block, South China, Gondwana Research, 20(2–3): Wang, L. J., Yu, J. H., O'Reilly, S. Y., et al., 2008. Grenvillian Orogeny in the 553–567. doi:10.1016/j.gr.2011.01.005 Southern Cathaysia Block: Constraints from U-Pb Ages and Lu-Hf Isotopes Yin, B. A., 1997. Lithostratigraphy of Guangxi Province. China University of in Zircon from Metamorphic Basement. Chinese Science Bulletin, 53(19): Geosciences Press, Wuhan. 310 (in Chinese) 3037–3050. doi:10.1007/s11434-008-0262-0 Yu, J. H., O’Reilly, S. Y., Wang, L. J., et al., 2010. Components and Episodic Wang, P. M., Yu, J. H., Sun, T., et al., 2012. Geochemistry and Detrital Zircon Growth of Precambrian Crust in the Cathaysia Block, South China: Evidence Geochronology of Neoproterozoic Sedimentary Rocks in Eastern Hunan from U-Pb Ages and Hf Isotopes of Zircons in Neoproterozoic Sediments. Province and Their Tectonic Significance. Acta Petrologica Sinica, 28(12): Precambrian Research, 181(1–4): 97–114. 3841–3857 (in Chinese with English Abstract) doi:10.1016/j.precamres.2010.05.016 Wang, P. M., Yu, J. H., Sun, T., et al., 2013. Composition Variations of the Yu, J. H., O’Reilly, S. Y., Suzanne, S. Y., et al., 2008. Where Was South China Sinian-Cambrian Sedimentary Rocks in Hunan and Guangxi and Their Tec- in the Rodinia Supercontinent? Evidence from U-Pb Geochronology and Hf tonic Significance. Science China: Earth Sciences, 56(11): 1899–1917. Isotopes of Detrital Zircons. Precambrian Research, 164(1–2): 1–15 doi:10.1007/s11430-013-4634-1 Zhang, S. B., Zheng, Y. F., Wu, F. Y., et al., 2006. Zircon U-Pb Age and Hf Wang, W., Zhou, M. F., 2012. Sedimentary Records of the Yangtze Block (South Isotope Evidence for 3.8 Ga Crustal Remnant and Episodic Reworking of China) and Their Correlation with Equivalent Neoproterozoic Sequences on Archean Crust in South China. Earth and Planetary Science Letters, Adjacent Continents. Sedimentary Geology, 265–266: 126–142. 252(1–2): 56–71. doi:10.1016/j.epsl.2006.09.027 doi:10.1016/j.sedgeo.2012.04.003 Zhao, G. C., Cawood, P. A., 2012. Precambrian Geology of China. Precambrian Wang, W., Zhou, M.F., Yan, D. P., et al,. 2012. Depositional Age, Provenance, Research, 222–223: 13–54. doi:10.1016/j.earscirev.2004.02.003 and Tectonic Setting of the Neoproterozoic Sibao Group, Southeastern Zhao, G. C., Sun, M., Wilde, S. A., et al., 2004. A Paleo-Mesoproterozoic Su- Yangtze Block, South China. Precambrian Research, 192–195(1): 107–124. percontinent: Assembly, Growth and Breakup. Earth Science Reviews, doi:10.1016/j.precamres.2011.10.010 67(1–2): 91–123 Wang, Y. J., Fan, W. M., Guo, F., et al., 2003. Geochemistry of Mesozoic Mafic Zhao, X. F., Zhou, M. F., Li, J. W., et al., 2010. Late Paleoproterozoic to Early Rocks around the Chenzhou-Linwu Fault in South China: Implication for the Mesoproterozoic Dongchuan Group in Yunnan, SW China: Implications for Lithospheric Boundary between the Yangtze and the Cathaysia Blocks. In- Tectonic Evolution of the Yangtze Block. Precambrian Research, 182(1–2): ternational Geology Review, 45(3): 263–286 57–69. doi:10.1016/j.precamres.2010.06.021 Wang, Y. J., Zhang, Y. Z., Fan, W. M., et al., 2014. Early Neoproterozoic Accre- Zheng, Y. F., Zhang, S. B., Zhao, Z. F., et al., 2007. Contrasting Zircon Hf and O tionary Assemblage in the Cathaysia Block: Geochronological, Lu-Hf Iso- Isotopes in the Two Episodes of Neoproterozoic Granitoids in South China: topic and Geochemical Evidence from Granitoid Gneisses. Precambrian Implications for Growth and Reworking of Continental Crust. Lithos, Research, 249(4): 144–161.doi:10.2747/0020-6814.45.3.263 96(1–2): 127–150. doi:10.1016/j.lithos.2006.10.003 Wang, Y. J., Zhang, F. F., Fan, W. M., et al., 2010. Tectonic Setting of the South Zhou, Q., Du, Y. S., Yuan, L. J., et al., 2016. The Structure of the Wuling Rift China Block in the Early Paleozoic: Resolving Intracontinental and Ocean Basin and Its Control on the Manganese Deposit during the Nanhua Period Closure Models from Detrital Zircon U-Pb Geochronology. Tectonics, 29(6): in Guizhou Hunan Chongqing Border Area, South China. Earth TC6020. doi:10.1016/j.precamres.2014.05.003 Science—Journal of China University of Geosciences, 41(2): 177–188 Xiang, L., Shu, L.S., 2010. Pre-Devonian Tectonic Evolution of the Eastern Zhou, M. F., Yan, D. P., Kennedy, A. K., et al., 2002. SHRIMP U-Pb Zircon South China Block: Geochronological Evidence from Detrital Zircons, Earth Geochronological and Geochemical Evidence for Neoproterozoic Sciences, 53(10): 1427–1444 Arc-Magmatism along the Western Margin of the Yangtze Block, South Xiao, Z. B., 2012. Reseach of the Detrital Zircon from Mesoproterozoic Sedi- China. Earth and Planetary Science Letters, 196(1–2): 51–67. mentary Strata in the North Margin of Yangtze Craton, China: [Dissertation]. doi:10.1016/s0012-821x(01)00595-7 Northwest University, Xi’an (in Chinese with English Abstract)