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Nature and origin of the volcanic ash beds near the Permian–Triassic boundary in South China: new data and their geological implications

Published online by Cambridge University Press:  03 December 2019

Binsong Zheng*
Affiliation:
School of Earth Sciences, China University of Geosciences, Wuhan430074, China Chinese Academy of Geological Sciences, Beijing100037, China Chengdu Institute of Geology and Mineral Resources, Chengdu610081, China Key Laboratory for Sedimentary Basin and Oil and Gas Resources, Ministry of Natural Resources, Chengdu610081, China
Chuanlong Mou*
Affiliation:
School of Earth Sciences, China University of Geosciences, Wuhan430074, China Chinese Academy of Geological Sciences, Beijing100037, China Chengdu Institute of Geology and Mineral Resources, Chengdu610081, China Key Laboratory for Sedimentary Basin and Oil and Gas Resources, Ministry of Natural Resources, Chengdu610081, China College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao266590, China
Renjie Zhou
Affiliation:
School of Earth and Environmental Sciences, University of Queensland, St Lucia4072, Australia
Xiuping Wang
Affiliation:
Chengdu Institute of Geology and Mineral Resources, Chengdu610081, China Key Laboratory for Sedimentary Basin and Oil and Gas Resources, Ministry of Natural Resources, Chengdu610081, China
Zhaohui Xiao
Affiliation:
Hubei Shale Gas Development Co. Ltd, Wuhan430071, China
Yao Chen
Affiliation:
Hubei Shale Gas Development Co. Ltd, Wuhan430071, China
*
Author for correspondence: Binsong Zheng and Chuanlong Mou, Emails: michael199062@126.com and cdmchuanlong@163.com
Author for correspondence: Binsong Zheng and Chuanlong Mou, Emails: michael199062@126.com and cdmchuanlong@163.com
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Abstract

Permian–Triassic boundary (PTB) volcanic ash beds are widely distributed in South China and were proposed to have a connection with the PTB mass extinction and the assemblage of Pangea. However, their source and tectonic affinity have been highly debated. We present zircon U–Pb ages, trace-element and Hf isotopic data on three new-found PTB volcanic ash beds in the western Hubei area, South China. Laser ablation inductively coupled plasma mass spectrometry U–Pb dating of zircons yields ages of 252.2 ± 3.6 Ma, 251.6 ± 4.9 Ma and 250.4 ± 2.4 Ma for these three volcanic ash beds. Zircons of age c. 240–270 Ma zircons have negative εHf(t) values (–18.17 to –3.91) and Mesoproterozoic–Palaeoproterozoic two-stage Hf model ages (THf2) (1.33–2.23 Ga). Integrated with other PTB ash beds in South China, zircon trace-element signatures and Hf isotopes indicate that they were likely sourced from intermediate to felsic volcanic centres along the Simao–Indochina convergent continental margin. The Qinling convergent continental margin might be another possible source but needs further investigation. Our data support the model that strong convergent margin volcanism took place around South China during late Permian – Early Triassic time, especially in the Simao–Indochina active continental margin and possibly the Qinling active continental margin. These volcanisms overlap temporally with the PTB biocrisis triggered by the Siberian Large Igneous Province. In addition, our data argue that the South China Craton and the Simao–Indochina block had not been amalgamated with the main body of Pangea by late Permian – Early Triassic time.

Type
Original Article
Copyright
© Cambridge University Press 2019

1. Introduction

Permian–Triassic boundary (PTB) volcanic ash beds are widely distributed in South China (Fig. 1). Their nature and origin have been studied for decades due to a possible relationship with the PTB mass extinction event and the assemblage of Pangea (e.g. Yin et al. Reference Yin, Feng, Lai, Baud and Tong2007; Shen et al. Reference Shen, Crowley, Wang, Bowring, Erwin, Sadler, Cao, Rothman, Henderson, Ramezani, Zhang, Shen, Wang, Wang, Mu, Li, Tang, Liu, Liu, Zeng, Jiang and Jin2011a; Burgess et al. Reference Burgess, Bowring and Shen2014; Baresel et al. Reference Baresel, Bucher, Brosse, Cordey, Guodun and Schaltegger2017). Petrographic and mineralogical studies demonstrate a felsic nature for these volcanic ash beds (He et al. Reference He, Chai and Ma1989; Yin et al. Reference Yin, Huang, Zhang, Yang, Ding, Bi and Zhang1989, Reference Yin, Huang, Zhang, Hansen, Yang, Ding, Bie, Sweet, Yang, Dickins and Yin1992; Yang et al. Reference Yang, Wu, Yin, Xu, Zhang and Bi1991). The connection between the PTB mass extinction and the Siberian Large Igneous Province led to the conclusion that these ash beds may represent distal deposits from basaltic volcanisms of the Siberian Large Igneous Province (e.g. Shen et al. Reference Shen, Algeo, Hu, Zhang, Zhou, Xia, Xie and Feng2012). Studies on platinum-group elements in the PTB global stratotype section and point Meishan section also suggest a source from the Siberian Large Igneous Province and probably the Emeishan Large Igneous Province (Xu et al. Reference Xu, Lin, Shen, Qi, Xie and Ouyang2007). Coeval tuffs found on the uppermost of the Emeishan basalt succession have led to the conclusion that these tuffs were sourced from the Emeishan Large Igneous Province (Zhu et al. Reference Zhu, Zhang, Hou and Kang2011). However, recent studies (Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015; He et al. Reference He, Zhong, Xu and Li2014) based on U–Pb ages, trace elements and Hf isotopes of zircons suggest that these volcanic ash beds may be sourced from convergent continental margins in the eastern Tethyan region, but precise locations are subject to debate. Existing studies argue for the convergent continental margin of the southwestern South China Craton (Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015) or the convergent continental margin in the East Kunlun area (He et al. Reference He, Zhong, Xu and Li2014). In addition, these convergent events may have led to the amalgamation of East Asian blocks and Pangea (e.g. Metcalfe Reference Metcalfe, Hall and Blundell1996, Reference Metcalfe2013; Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018; Zhao et al. Reference Zhao, Zhang, Wang, Huang, Dong, Li and Yu2018). The timing of the amalgamation is still under debate, however (e.g. Scotese & McKerrow, Reference Scotese, McKerrow, McKerrow and Scotese1990; Collins, Reference Collins2003; Scotese, Reference Scotese2004; Golonka et al. Reference Golonka, Krobicki, Pająk, Nguyen and Zuchiewicz2006; Golonka, Reference Golonka2007; Metcalfe, Reference Metcalfe, Buffetaut, Cuny, Le Loeuff and Suteethorn2009; van der Meer et al. Reference van der Meer, Spakman, van Hinsbergen, Amaru and Torsvik2010; Cocks & Torsvik, Reference Cocks and Torsvik2013; Stampfli et al. Reference Stampfli, Hochard, Vérard, Wilhem and von Raumer2013; Domeier & Torsvik, Reference Domeier and Torsvik2014; Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018; Zhao et al. Reference Zhao, Zhang, Wang, Huang, Dong, Li and Yu2018).

Fig. 1. Distribution of PTB volcanic ash beds in South China (upper part) and correlation of representative PTB sections (lower part). The semitransparent areas in the upper map represent the distribution of volcanic ash beds, and n represents the number of sections. Volcanic ash bed localities and lithological columns are compiled from Yin et al. (Reference Yin, Huang, Zhang, Yang, Ding, Bi and Zhang1989), Yang et al. (Reference Yang, Wu, Yin, Xu, Zhang and Bi1991, Reference Yang, Cawood, Du, Huang, Huang and Tao2012), Shen et al. (Reference Shen, Crowley, Wang, Bowring, Erwin, Sadler, Cao, Rothman, Henderson, Ramezani, Zhang, Shen, Wang, Wang, Mu, Li, Tang, Liu, Liu, Zeng, Jiang and Jin2011a), Zhu et al. (Reference Zhu, Zhang, Hou and Kang2011), Gao et al. (Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015), Burgess et al. (Reference Burgess, Bowring and Shen2014), He et al. (Reference He, Zhong, Xu and Li2014), Liao et al. (Reference Liao, Hu, Cao, Wang, Yao and Wan2016a, b), Baresel et al. (Reference Baresel, Bucher, Brosse, Cordey, Guodun and Schaltegger2017) and the SHP section in this study. Tectonic boundaries are from Zhang et al. (Reference Zhang, Dong, Lai, Guo, Meng, Liu, Cheng, Yao, Zhang, Pei and Li2004).

The PTB mass extinction was proposed to be triggered by Siberian Large Igneous Province flood basalt volcanism, which induced a world-wide lethally hot climate (e.g. Svensen et al. Reference Svensen, Planke, Polozov, Schmidbauer, Corfu, Podladchikov and Jamtveit2009; Joachimski et al. Reference Joachimski, Lai, Shen, Jiang, Luo, Chen, Chen and Sun2012; Sun et al. Reference Sun, Joachimski, Wignall, Yan, Chen, Jiang, Wang and Lai2012; Retallack, Reference Retallack2013; Cui & Kump, Reference Cui and Kump2015; Shen et al. Reference Shen, Feng, Algeo, Li, Planavsky, Zhou and Zhang2016). Additionally, the timing of the PTB biocrisis and late Permian – Early Triassic convergent margin volcanism in the Palaeotethyan region has suggested that the Palaeotethys ignimbrite flare-up may also have contributed to the PTB mass extinction (e.g. Isozaki, Reference Isozaki2009; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013; He et al. Reference He, Zhong, Xu and Li2014), but details of their relationship are still unclear.

In this study, we present data from three newly found PTB volcanic ash beds in the western Hubei area, South China, including zircon U–Pb ages, trace elements and Hf isotopes, and compare them with other PTB volcanic ash beds in South China. The source and tectonic affinity of these ashes are discussed. In addition, we also explore their possible relationship with the PTB mass extinction and the assemblage of Pangea.

2. Geological background

In South China, PTB volcanic ash beds, most of which have been diagenetically altered to clay beds, are widely distributed; up to 35 beds with a total thickness of up to 20 cm may be found in a single section (Fig. 1) (Yin et al. Reference Yin, Huang, Zhang, Yang, Ding, Bi and Zhang1989; Yang et al. Reference Yang, Wu, Yin, Xu, Zhang and Bi1991; He et al. Reference He, Zhong, Xu and Li2014). Their distinct color (e.g. white, yellow, light grey or greyish-green) and high content of clay minerals make them distinguishable from their surrounding rocks in the outcrop (Yang et al. Reference Yang, Wu, Yin, Xu, Zhang and Bi1991; Yin et al. Reference Yin, Huang, Zhang, Hansen, Yang, Ding, Bie, Sweet, Yang, Dickins and Yin1992; Hong et al. Reference Hong, Zhang, Li, Xue, Xia and Yu2008). Weighted mean ages of zircons from these ash beds range from 254.31 ± 0.07 Ma to 246.8 ± 1.3 Ma (Shen et al. Reference Shen, Crowley, Wang, Bowring, Erwin, Sadler, Cao, Rothman, Henderson, Ramezani, Zhang, Shen, Wang, Wang, Mu, Li, Tang, Liu, Liu, Zeng, Jiang and Jin2011a; Zhu et al. Reference Zhu, Zhang, Hou and Kang2011; Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015; Burgess et al. Reference Burgess, Bowring and Shen2014; He et al. Reference He, Zhong, Xu and Li2014; Liao et al. Reference Liao, Hu, Cao, Wang, Yao and Wan2016a; Baresel et al. Reference Baresel, Bucher, Brosse, Cordey, Guodun and Schaltegger2017).

The Shuanghe Poumian (SHP) section is located at the village of Shuanghe village, western Hubei area in the northern margin of South China Craton (30° 9′ 49.6″ N, 109° 48′ 6.4″ E). A continuous and well-exposed upper Permian – Lower Triassic deepwater succession has recently been identified (Figs 1, 2). The lower part of the SHP section is composed of the upper Permian Dalong Formation and the upper part is the Lower Triassic Daye Formation (Fig. 3). The Dalong Formation is c. 60 m thick and mainly composed of carbonaceous mudstone and chert with mudstone occasionally interbedded (Fig. 3). The lower part of the Daye Formation is approximately 25 m thick and mainly composed of interbedded limestone and mudstone (Fig. 3). The rest part of the Daye Formation is composed of limestone of approximately 800 m thickness. Biostratigraphy indicates a time range of late Wuchiapingian (late Permian) to Induan (Early Triassic), that is, c. 255–250 Ma (Gradstein et al. Reference Gradstein, Ogg, Schmitz and Ogg2012), for the deposition of the Dalong Formation and the lower part of the Daye Formation (Fig. 4) (Zhang et al. Reference Zhang, He, Zhang, Yang and Wu2009; Feng & Algeo, Reference Feng and Algeo2014; Zheng et al. Reference Zheng, Mou, Wang, Xiao and Chen2019). Three PTB volcanic ash beds (beds 1 to 3) were studied (Figs 1, 3).

Fig. 2. (a) Global palaeogeography at PTB (modified from Spörli et al. Reference Spörli, Aita, Hori, Takemura, Spörli, Takemura and Hori2007). (b) Changhsingian palaeogeography of South China (modified from Feng et al. Reference Feng, Yang, Jin, He, Wu, Xin, Bao and Tan1996b; Feng & Algeo, Reference Feng and Algeo2014). 1 – land; 2 – continental facies; 3 – littoral detrital facies; 4 – shallow-water carbonate; 5 –deep-water chert-mudstone; NCC – North China Craton; SCC – South China Craton; SHP – Shuanghe Poumian.

Fig. 3. Lithologic column of the SHP section and sample locations.

Fig. 4. The late Permian – Early Triassic succession of the study area (after Zhang et al. Reference Zhang, He, Zhang, Yang and Wu2009; Zheng et al. Reference Zheng, Mou, Wang, Xiao and Chen2019). The ages of the succession are from Gradstein et al. (Reference Gradstein, Ogg, Schmitz and Ogg2012).

3. Samples and analytical methods

3.a. Sample description

Volcanic ash beds 1 to 3 were sampled and labelled as ZC, ZE and ZG, respectively (Fig. 3). These volcanic ash beds are 4–8 cm thick. They are distinct from their surrounding rocks in the outcrop due to their unique colour and high content of clay minerals similar to other sections in the adjacent area (Hong et al. Reference Hong, Zhang, Li, Xue, Xia and Yu2008; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013). Bed 1 is yellow to grey in colour and interbedded with carbonaceous mudstone at the top of the Dalong Formation. It contains millimetre-scale volcanic debris, indicating a proximal volcanic eruption (Fig. 5a, b). Beds 2 and 3 are grey-green in colour and interbedded with mudstone or limestone at the lower part of the Daye Formation (Fig. 5c, d).

Fig. 5. Outcrop photographs of the studied volcanic ash beds in the SHP section: (a, b) bed 1 (sample ZC) and (c, d) bed 3 (sample ZG).

3.b. Analytical methods

Zircon grains were separated using a combination of heavy liquid and magnetic separation techniques. Zircon grains were handpicked and mounted in epoxy and polished. Zircon grains were imaged by a Gatan mini-cathodoluminescence (CL) spectroscope attached to a JSM6510 scanning electron microscope at Langfang Yuheng Mineral and Rock Service Ltd., Hebei, China, in order to reveal their internal structures.

U–Pb dating and trace-element analysis of zircons were conducted using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) at the Key Laboratory for the study of focused Magmatism and Giant Ore Deposits, Ministry of Natural Resources, in Xi’an Center of Geological Survey, China Geological Survey. Reference materials, 91500 and Plesovice zircons, and NIST610 glass were used. Laser ablation was performed using a GeoLas Pro laser-ablation system coupled to an Agilent 7700 × ICP-MS and the beam diameter was 24 μm. Each analysis incorporated a background acquisition of approximately 10 s (gas blank) followed by 40 s data acquisition. The Agilent Chemstation was utilized for the acquisition of each individual analysis. Off-line selection and integration of background and analytical signals, and time-drift correction and quantitative calibration for U–Pb dating, were performed using UranOS 2.06a (http://www.sediment.uni-goettingen.de/staff/dunkl/software) and trace-element analyses using Iolite 3.0 (http://iolite-software.com/). Weighted mean U–Pb ages (with 95% confidence) and concordia plots were generated by IsoPlot 3.75 (Ludwig, Reference Ludwig2012). Grain ages use 207Pb/206Pb ages for grains older than 1.0 Ga and 206Pb/238U ages for younger grains.

In situ zircon Hf isotope analysis was performed using a GeoLas Pro laser-ablation system coupled to a Neptune multiple-collector ICP-MS at Xi’an Center of Geological Survey, China Geological Survey. Details of the instrumental conditions and data acquisition procedures are described by Meng et al. (Reference Meng, Liu, Liu, Liu, Yang, Wang, Shi and Cai2014). A beam diameter of 32 μm was used on top of the existing laser pit for U–Pb for those zircons with large grain sizes. Correction factors for 176Lu and 176Yb isobaric interferences on 176Hf are 176Lu/175Lu = 0.02658 and 176Yb/173Yb = 0.796218 (Chu et al. Reference Chu, Taylor, Chavagnac, Nesbitt, Boella, Milton, German, Bayon and Burton2002). Instrumental mass bias was corrected by normalizing Yb isotope ratios to 172Yb/173Yb = 1.35274 (Chu et al. Reference Chu, Taylor, Chavagnac, Nesbitt, Boella, Milton, German, Bayon and Burton2002) and Hf isotopic ratios to 179Hf/177Hf = 0.7325 using an exponential mass fractionation law. The mass bias behaviour of Lu was assumed to follow that of Yb. Details of the mass bias correction protocols are described in Iizuka & Hirata (Reference Iizuka and Hirata2005), Wu et al. (Reference Wu, Yang and Xie2006) and Hou et al. (Reference Hou, Li, Zou, Qu, Shi and Xie2007). Zircon GJ-1 was used as the reference standard and yielded a weighted mean 176Hf/177Hf ratio of 0.282030 ± 40 (2σ) for this study. This ratio overlaps with a weighted mean 176Hf/177Hf ratio of 0.282013 ± 19 (2σ) obtained by Elhlou et al. (Reference Elhlou, Belousova, Griffin, Pearson and O’Reilly2006). T Hf and T Hf2 are single- and two-stage Hf model ages, respectively. The ε Hf, T Hf and f Lu/Hf in this study are calculated following Meng et al. (Reference Meng, Liu, Liu, Liu, Yang, Wang, Shi and Cai2014), where: the decay constant for 176Lu is 1.867 × 10−11 a−1 (Amelin, Reference Amelin2005); 176Lu/177 Hf and 176Hf/177 Hf ratios for the chondritic reservoir are 0.0332 and 0.282772, respectively (Blichert-Toft & Albarede, Reference Blichert-Toft and Albarede1997); 176Lu/177Hf and present-day 176Hf/177Hf ratios for the depleted mantle are 0.0384 and 0.28325, respectively (Griffin et al. Reference Griffin, Pearson, Belousova, Jackson, van Achterbergh, O’Reilly and Shee2000); and the 176Lu/177 Hf ratio for average continental crust is 0.015 (Griffin et al. Reference Griffin, Wang, Jackson, Pearson and O’Reilly2002).

4. Results

4.a. Zircon U–Pb ages

A total of 43 zircons from sample ZC (bed 1), 40 from sample ZE (bed 2) and 57 from sample ZG (bed 3) were dated (online Supplementary Table S1, available at http://journals.cambridge.org/geo). Analysed zircons are 60–200 µm prismatic euhedral crystals (Fig. 6), suggesting little transportation. Most of them have distinct oscillatory zoning, implying a magmatic origin (Fig. 6).

Fig. 6. Representative zircon CL images of our samples and their U–Pb ages and ε Hf(t) values. Circles represent laser pits.

Among all zircons, 27 from ZC, 29 from ZE and 42 from ZG yield concordant U–Pb ages, and abundant ages fall near the PTB ranging from 237.2 ± 14.8 Ma to 271 ± 14.3 Ma (n = 90), which we used to calculate ages for the studied ash beds and obtained 252.2 ± 3.6 Ma (MSWD = 1.6) for Bed 1 (ZC), 251.6 ± 4.9 Ma (MSWD = 0.12) for Bed 2 (ZE) and 250.4 ± 2.4 Ma (MSWD = 0.46) for Bed 3 (ZG) (Supplementary Table S1; Fig. 7). Inherited zircon ages range from 444.8 ± 42.7 Ma to 2305.8 ± 60.4 Ma (n = 8) (Supplementary Table S1; Fig. 7).

Fig. 7. Zircon U–Pb concordia plots of samples (data-point error ellipses are 2σ).

4.b. Zircon trace elements

All zircons were analysed for their trace elements (online Supplementary Table S2, available at http://journals.cambridge.org/geo) and those with concordant U–Pb ages are summarized as follows. For all the samples, yttrium (Y) content ranges from 196 to 7340 ppm, hafnium (Hf) content ranges from 11090 to 18600 ppm and lead (Pb) content ranges from 11 to 735 ppm. The Th/U ratio ranges from 0.308 to 0.88 for sample ZC, 0.205–1.429 for sample ZE and 0.235–1.064 for sample ZG (Supplementary Table S1), indicating a magmatic origin (Rubatto, Reference Rubatto2002). The chondrite-normalized rare Earth element (REE) pattern shows enrichment of heavy rare Earth elements (HREE), positive Ce anomaly and negative Eu anomaly, similar to other PTB volcanic ash beds in South China (Fig. 8).

Fig. 8. Chondrite-normalized REE patterns for zircons. Chondritic values used for normalization are from Taylor & McLennan (Reference Taylor and McLennan1981). Curves represent zircons from the SHP section. Shaded areas are compiled from other PTB volcanic ash beds in South China (Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015).

4.c. Zircon Hf isotopes

Sixty zircon grains were analysed by in situ zircon Hf isotope analysis (online Supplementary Table S3, available at http://journals.cambridge.org/geo; Fig. 9a). ε Hf(t) values of the zircons aged c. 240–270 Ma range from –18.17 to –3.91, which is generally more negative than zircons from other volcanic ash beds in South China (Fig. 9b). Their T Hf ages range from 0.84 to 1.46 Ga and T Hf2 ages range from 1.33 to 2.23 Ga. For inherited zircons, the ε Hf(t) values range from –50.98 to –9.59 with T Hf ages of 1.05–2.73 Ga and T Hf2 ages of 1.69–4.23 Ga.

Fig. 9. ε Hf(t) plots for zircons: (a) from the SHP section; and (b) of age c. 240–270 Ma different PTB sections in South China. Daxiakou section is from Gao et al. (Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013), Zunyi section is from Gao et al. (Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015), Meishan section, Chaotian section, Shangsi section and Dongpan section are from He et al. (Reference He, Zhong, Xu and Li2014).

5. Discussion

5.a. Source and tectonic affinity of the volcanic ash beds

Trace elements may be diagnostic for source rocks and related tectonic backgrounds for magmatic zircons (Shnukov et al. Reference Shnukov, Andreev and Savenok1997; Belousova et al. Reference Belousova, Griffin, O’Reilly and Fisher2002; Grimes et al. Reference Grimes, John, Kelermen, Mazdab, Wooden, Cheadle, Hanghoj and Schwartz2007; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013). Y versus U and Y versus (Yb/Sm)N plots show that zircons from PTB volcanic ash beds in the SHP section, as well as in other PTB sections in South China, were mainly distributed in the areas of felsic rocks, such as granitoids, larvikites and syenite pegmatites, and the area of mafic rocks that overlaps with felsic rocks (Fig. 10a, b). The Y versus Hf plot points to an intermediate to felsic source (Fig. 10c). The Y versus (U/Yb) diagram shows that these zircons were most likely sourced from felsic volcanic sources at convergent continental margins before post-collisional extension (Fig. 10d).

Fig. 10. Trace-element diagrams for source rock and tectonic setting discrimination of the zircons aged c. 240–270 Ma. (a–c) Y versus U, Y versus (Yb/Sm)N and Hf versus Y diagrams for source-rock discrimination (Shnukov et al. Reference Shnukov, Andreev and Savenok1997; Belousova et al. Reference Belousova, Griffin, O’Reilly and Fisher2002), where subscript N represents chondrite-normalized value; I – kimberlites; II – ultramafic, mafic and intermediate rocks; III – quartz-bearing intermediate and felsic rocks; IV – felsic rocks with high SiO2 content; V – greisens; VI – alkaline rocks and alkaline metasomatites of alkaline complexes; VII – carbonatites. (d) U/Yb versus Y diagram for tectonic setting discrimination (Grimes et al. Reference Grimes, John, Kelermen, Mazdab, Wooden, Cheadle, Hanghoj and Schwartz2007; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013). The red circle represents zircons from felsic rocks at convergent continental margins before post-collisional extension. The shaded area represents data compiled from other PTB volcanic ash beds in South China (after Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015).

The values of ε Hf(t) and T Hf2 ages of the zircons aged c. 240–270 Ma in the SHP section as well as in other PTB sections in South China indicate that the parent magma might be mainly sourced from Palaeoproterozoic–Mesoproterozoic crustal materials (online Supplementary Table S3, available at http://journals.cambridge.org/geo; Figs 9, 11). However, pre-Palaeoproterozoic T Hf2 ages from ancient zircon cores (Figs 9, 11) provide a possibility that the source of magma may require some contribution from younger (post-Mesoproterozoic) juvenile materials. Slightly positive to slightly negative ε Hf(t) values in some sections also imply a contribution from juvenile mantle-derived mafic materials to the source magma (Fig. 9b) (e.g. Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013).

Fig. 11. T Hf2 ages of zircons from different PTB volcanic ash beds in South China. Daxiakou section is from Gao et al. (Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013), Zunyi section is from Gao et al. (Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015), and Meishan, Chaotian, Shangsi and Dongpan sections are from He et al. (Reference He, Zhong, Xu and Li2014).

In summary, PTB volcanic ash beds in South China may be sourced from intermediate to felsic volcanisms at convergent continental margins before post-collisional extension. Their source magma may have been mainly derived from Palaeoproterozoic–Mesoproterozoic crustal materials with juvenile mantle-derived mafic materials contributing to varying degrees.

5.b. Location of the volcanic source

Two theories exist for the source of PTB volcanic ash beds in South China. A first view suggests that these volcanic ash beds may be sourced from the Siberian Large Igneous Province and probably the Emeishan Large Igneous Province (e.g. Xu et al. Reference Xu, Lin, Shen, Qi, Xie and Ouyang2007; Zhu et al. Reference Zhu, Zhang, Hou and Kang2011; Shen et al. Reference Shen, Algeo, Hu, Zhang, Zhou, Xia, Xie and Feng2012). For the Siberian Large Igneous Province, the maximum age for pyroclastic magmatism was dated at 255.58 ± 0.38 Ma and the youngest felsic tuff bed was dated at 251.403 ± 0.048 Ma (Burgess & Bowring, Reference Burgess and Bowring2015), indicating an overlap in timing with those coeval volcanic ash beds in South China except for those later during Early Triassic time. For the Emeishan Large Igneous Province in southwestern South China, the major basaltic eruption is thought to have occurred at c. 260 Ma (He et al. Reference He, Xu, Chung, Xiao and Wang2003) and the associated intermediate to felsic plutons were dated at c. 260–251 Ma (Xu et al. Reference Xu, Luo, Huang, He, Xiao, Xie and Shi2008; Shellnutt et al. Reference Shellnutt, Wang, Zhou and Yang2009; Zhong et al. Reference Zhong, Zhu, Hu, Xie, He, Liu and Chu2009, Reference Zhong, Campbell, Zhu, Allen, Hu, Xie and He2011; He, Reference He2016), regardless of the compositional discrepancy, also suggesting a timing overlap with those coeval volcanic ash beds in South China except for those later during Early Triassic time. A second view argues that they may have been sourced from intermediate to felsic volcanism that is related to the closure of the Palaeotethys Ocean or the formation of the Pangea supercontinent (Clark et al. Reference Clark, Wang, Orth and Gilmore1986; He et al. Reference He, Chai and Ma1989, Reference He, Zhong, Xu and Li2014; Yin et al. Reference Yin, Huang, Zhang, Yang, Ding, Bi and Zhang1989, Reference Yin, Huang, Zhang, Hansen, Yang, Ding, Bie, Sweet, Yang, Dickins and Yin1992, Reference Yin, Feng, Lai, Baud and Tong2007; Yang et al. Reference Yang, Wu, Yin, Xu, Zhang and Bi1991, Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Isozaki et al. Reference Isozaki, Shimizu, Yao, Ji and Matsuda2007; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015).

Our data argue for a convergent continental margin source for the PTB ash beds in South China; however, the precise location of the source volcanism is subject to debate. Existing studies argue for the convergent continental margin of the southwestern South China Craton (Yang et al. Reference Yang, Cawood, Du, Huang, Huang and Tao2012; Gao et al. Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015) or the convergent continental margin in the East Kunlun area (He et al. Reference He, Zhong, Xu and Li2014). However, except for the intermediate to felsic nature and their tectonic affinity to magmatic arc, the link between these possible parent volcanisms and PTB volcanic ash beds in South China was mainly developed based on obtained ages and the spatial variation in the thickness and numbers of the PTB ash beds.

During late Permian – Early Triassic time, the subduction of the Palaeotethys Ocean resulted in the formation of several convergent continental margins in the eastern Palaeotethys region (Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018), including the Kunlun (e.g. Xiao et al. Reference Xiao, Windley, Hao and Li2002; Yan et al. Reference Yan, Bian, Korchagin, Pospelov, Li and Wang2008; Dai et al. Reference Dai, Wang, Hourigan and Santosh2013), Qinling (e.g. Guo et al. Reference Guo, Yan, Wang, Wang, Hou, Fu and Li2012; Yan et al. Reference Yan, Wang, Li, Xu and Deng2012, Reference Yan, Guo, Fu, Aitchison, Wang and Li2014; Dong & Santosh, Reference Dong and Santosh2016) and Simao–Indochina convergent continental margins (e.g. Cai & Zhang, Reference Cai and Zhang2009; Faure et al. Reference Faure, Lepvrier, Nguyen, Vu, Lin and Chen2014; Liu et al. Reference Liu, Wang, Li, Zi and Huangfu2018) (Fig. 12). These coeval convergent continental margins are the most likely sources for PTB ash beds in South China. Zircon Hf isotopes and model ages are useful indicators of tectonic setting and the nature of the associated magma, providing a possibility to precisely locate the parent volcanism of PTB ash beds in South China. Available data allow us to directly compare these Hf-related parameters of magmatic zircons in PTB ash beds in South China with those in coeval intermediate to felsic magmatic rocks (c. 255–246 Ma) in Simao–Indochina and East Kunlun convergent continental margins. For the coeval magmatic zircons in the Simao–Indochina convergent continental margin, both ε Hf(t) values and T Hf2 ages overlap those in PTB ash beds in South China, and their distribution patterns also show similarities with ε Hf(t) values of c. −12 to −4 and T Hf2 ages of c. 1.5–2.1 Ga (Fig. 13), indicating that the Simao–Indochina convergent continental margin may be the major source of PTB ash beds in South China. The coeval magmatic zircons in the East Kunlun convergent continental margin generally show higher ε Hf(t) values and younger T Hf2 ages compared with those in PTB ash beds in South China (Fig. 13), indicating the East Kunlun convergent continental margin is unlikely to be the major source. For the Qinling convergent continental margin, metamorphic ages of the subducted oceanic crust (Sun et al. Reference Sun, Williams and Li2002; Cheng et al. Reference Cheng, King, Nakamura, Vervoort, Zheng, Ota, Wu, Kobayashi and Zhou2009; Wu et al. Reference Wu, Hanchar, Gao, Sylvester, Tubrett, Qiu, Wijbrans, Brouwer, Yang, Yang, Liu and Yuan2009; Liu et al. Reference Liu, Wu, Gao, Wang, Peng, Gong, Liu and Yuan2011) and ages of arc-related volcanic rocks (Feng et al. Reference Feng, Du, Yin, Sheng and Xu1996a; Li et al. Reference Li, Hou, Yang, Sun, Zhang and Li2004) indicate that the subduction of the oceanic crust under the Qinling – North China composite continent occurred during Carboniferous time. Palaeomagnetic data (Zhao & Coe, Reference Zhao and Coe1987; Enkin et al. Reference Enkin, Yang, Chen and Courtillot1992; Yang et al. Reference Yang, Ma, Huang, Sun and Zhou1998; Zhu et al. Reference Zhu, Yang, Wu, Ma, Huang, Meng and Fang1998; Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018) and high and ultrahigh-pressure eclogite facies metamorphic events in the Dabie mountains (Liu et al. Reference Liu, Jahn, Dong, Lou and Cui2008; Cheng et al. Reference Cheng, Zhang, Vervoort, Wu, Zheng, Zheng and Zhou2011; Gao et al. Reference Gao, Zheng and Chen2011; Liu & Liou, Reference Liu and Liou2011) support a scissors-like closure of the ocean between South and North China cratons that was initiated during Late Permian time, with its eastern part closed earlier. The final collision in the western orogen occurred during late Triassic time as evidenced by a large volume of collision-related granitoids in the western Qinling area (Wang et al. Reference Wang, Wang and Zhang2015). However, the suture zone has been intensely reworked by the Mesozoic and Cenozoic intracontinental orogeny and mostly covered by the Bashan arcuate thrust system (Zhang et al. Reference Zhang, Dong, Lai, Guo, Meng, Liu, Cheng, Yao, Zhang, Pei and Li2004), and the late Permian – Early Triassic intermediate to felsic magmatic rocks have not yet been found. However, as an adjacent coeval active continental margin (Fig. 12), it cannot be excluded as a possible source for the PTB ash beds in South China. Considering the large number of PTB ash beds and their wide distribution in South China (Fig. 1), they may not be derived from a single source. For example, magmatic zircons in the SHP section, adjacent to the Qinling convergent continental margin (Fig. 12), generally show lower ε Hf(t) values and older T Hf2 ages compared with those in other PTB ash beds in South China (Fig. 13), providing the possibility that they may be sourced from the Qinling convergent continental margin.

Fig. 12. Late Permian palaeogeography map of the Palaeotethys region showing the convergent continental margins around South China (modified from Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018). Detailed palaeogeography of South China Craton is shown in Figure 2b.

Fig. 13. Zircon ε Hf(t) value and T Hf2 age histograms of PTB ash beds in South China and late Permian – Early Triassic intermediate to felsic magmatic rocks in Simao–Indochina and East Kunlun convergent continental margins. Data for South China PTB ash beds are compiled from Gao et al. (Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013, Reference Gao, Chen, Zhang, Griffin, Xia, Wang, Jiang, Xia and O’Reilly2015) and He et al. (Reference He, Zhong, Xu and Li2014). Data for Simao–Indochina convergent continental margin are compiled from Zi et al. (Reference Zi, Cawood, Fan, Tohver, Wang and McCuaig2012), Li et al. (Reference Li, Wang, Yu, Hu, Ma and Huang2013) and Liu et al. (Reference Liu, Wang, Cawood, Fan, Cai and Xing2015). Data for East Kunlun convergent continental margin are compiled from Huang et al. (Reference Huang, Niu, Nowell, Zhao, Yu, Zhu, Mo and Ding2014), Ding et al. (Reference Ding, Liu and Yan2015) and Ren et al. (Reference Ren, Wang, Zhang, Wang, Huang, Feng, Teschner and Song2016).

5.c. Geological implications

The c. 252 Ma PTB mass extinction caused a reduction of c. 70% of terrestrial and c. 90% of marine species and the ecosystem took 5 Ma or longer to recover from the extinction (Chen et al. Reference Chen, Algeo and Bottjer2014; Algeo et al. Reference Algeo, Chen and Bottjer2015). The Siberian Large Igneous Province flood basalt volcanism was proposed to trigger the PTB mass extinction by inducing the lethally hot climate (Wignall, Reference Wignall2001; Retallack & Jahren, Reference Retallack and Jahren2008; Svensen et al. Reference Svensen, Planke, Polozov, Schmidbauer, Corfu, Podladchikov and Jamtveit2009; Joachimski et al. Reference Joachimski, Lai, Shen, Jiang, Luo, Chen, Chen and Sun2012; Shen et al. Reference Shen, Algeo, Hu, Zhang, Zhou, Xia, Xie and Feng2012, Reference Shen, Algeo, Feng, Zhou, Feng, Zhang and Huang2013, Reference Shen, Feng, Algeo, Li, Planavsky, Zhou and Zhang2016; Sun et al. Reference Sun, Joachimski, Wignall, Yan, Chen, Jiang, Wang and Lai2012; Retallack, Reference Retallack2013; Cui & Kump, Reference Cui and Kump2015). In addition, Isozaki (Reference Isozaki2009) and He et al. (Reference He, Zhong, Xu and Li2014) proposed that possible Palaeotethys ignimbrite flare-up may have injected a large volume of sulphur aerosols and ash particles into the late Permian – Early Triassic stratosphere, which may have caused severe environmental changes in the biosphere in a ‘volcanic ash winter’ scenario. Shen et al. (Reference Shen, Sun, Lin, Liu and Chai2011b) and Gao et al. (Reference Gao, Zhang, Xia, Feng, Chen, Zheng, Griffin, O’Reilly, Pearson, Wang, Wu, Zhong and Sun2013) proposed that, as a plausible heat source, silicic volcanism at a convergent continental margin related to Palaeotethys subduction may also have triggered the widespread wildfires on the continent, evidenced by combustion-derived black carbon and polynuclear aromatic hydrocarbons found in sediments in the PTB global stratotype section and point Meishan section. Our data reveal that the long-term intermediate to felsic volcanism at convergent continental margins around South China overlap temporally with the PTB biocrisis triggered by the Siberian Large Igneous Province flood basalt volcanism.

Pangea formed at c. 320–250 Ma with Laurasia in the north and Gondwana in the south (Fig. 12) (Smith & Livermore, Reference Smith and Livermore1991; Murphy & Nance, Reference Murphy and Nance2008; Stampfli et al. Reference Stampfli, Hochard, Vérard, Wilhem and von Raumer2013). However, it is controversial whether East Asian blocks have ever been a part of Pangea before it broke up during Early Jurassic time (e.g. Scotese & McKerrow, Reference Scotese, McKerrow, McKerrow and Scotese1990; Collins, Reference Collins2003; Scotese, Reference Scotese2004; Golonka et al. Reference Golonka, Krobicki, Pająk, Nguyen and Zuchiewicz2006; Golonka, Reference Golonka2007; Metcalfe, Reference Metcalfe, Buffetaut, Cuny, Le Loeuff and Suteethorn2009; van der Meer et al. Reference van der Meer, Spakman, van Hinsbergen, Amaru and Torsvik2010; Cocks & Torsvik, Reference Cocks and Torsvik2013; Stampfli et al. Reference Stampfli, Hochard, Vérard, Wilhem and von Raumer2013; Domeier & Torsvik, Reference Domeier and Torsvik2014; Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018; Zhao et al. Reference Zhao, Zhang, Wang, Huang, Dong, Li and Yu2018). Regarding the South China Craton and the Simao–Indochina block, most reconstructions propose that they may have been separated from Pangea by the Palaeotethys Ocean (e.g. Collins, Reference Collins2003; Scotese, Reference Scotese2004; Golonka, Reference Golonka2007; Metcalfe, Reference Metcalfe, Buffetaut, Cuny, Le Loeuff and Suteethorn2009; Cocks & Torsvik, Reference Cocks and Torsvik2013; Domeier & Torsvik, Reference Domeier and Torsvik2014). Recent studies on palaeomagnetism and orogenic belts of East Asian blocks argue that these two blocks may have been connected to Pangea by c. 220 Ma (Huang et al. Reference Huang, Yan, Piper, Zhang, Yi, Yu and Zhou2018; Zhao et al. Reference Zhao, Zhang, Wang, Huang, Dong, Li and Yu2018). Our data support the theory that strong magmatic activity may have taken place in the Simao–Indochina active continental margin and possibly the Qinling active continental margin of North China Craton during late Permian – Early Triassic time, indicating that eastern branches of the Palaeotethys Ocean, which separated the South China Craton and Simao–Indochina block from Pangea, had not yet been completely consumed during this time (Fig. 12).

6. Conclusions

Three volcanic ash beds (beds 1 to 3) were reported in the late Permian – Early Triassic SHP section in the western Hubei area, South China. LA–ICP–MS U–Pb dating of zircons yields ages of 252.2 ± 3.6 Ma for bed 1, 251.6 ± 4.9 Ma for bed 2 and 250.4 ± 2.4 Ma for bed 3. Zircon trace-element signatures and Hf isotopes indicate that the PTB volcanic ash beds in South China were likely sourced from coeval intermediate to felsic volcanic sources at the Simao–Indochina convergent continental margin. The Qinling active continental margin may be another source, but this possibility requires further investigation before being considered seriously.

Our new data indicate that convergent continental margin magmatism took place around South China during late Permian – Early Triassic time, especially in the Simao–Indochina active continental margin and possibly the Qinling active continental margin. These volcanisms took place around the same time as the PTB biocrisis triggered by the Siberian Large Igneous Province. In addition, our data indicate that the South China Craton and Simao–Indochina block had not been amalgamated with Pangea by late Permian – Early Triassic time.

Acknowledgments

This work was supported by the Shale Gas Development Co. Ltd, Hubei Province, China (contract no. HBYYQ-GC1075) and the National Natural Science Foundation of China (project no. 41772113). Binsong Zheng was supported by the Joint Training study program for excellent doctoral candidates at the School of Earth Sciences, China University of Geosciences (Wuhan). We would also like to thank the editor and the reviewers for their constructive comments and suggestions.

Supplementary material

To view supplementary material for this article, please visit https://doi.org/10.1017/S001675681900133X.

References

Algeo, TJ, Chen, ZQ and Bottjer, DJ (2015) Global review of the Permian–Triassic mass extinction and subsequent recovery: part II. Earth-Science Reviews 149, 14.CrossRefGoogle Scholar
Amelin, Y (2005) Meteorite phosphates show constant 176Lu decay rate since 4557 million years ago. Science 310, 839–41.CrossRefGoogle ScholarPubMed
Baresel, B, Bucher, H, Brosse, M, Cordey, F, Guodun, K and Schaltegger, U (2017) Precise age for the Permian–Triassic boundary in South China from high-precision U-Pb geochronology and Bayesian age–depth modeling. Solid Earth 8, 361–78.CrossRefGoogle Scholar
Belousova, EA, Griffin, WL, O’Reilly, SY and Fisher, NI (2002) Igneous zircon: trace element composition as an indicator of source rock type. Contributions to Mineralogy and Petrology 143, 602–22.CrossRefGoogle Scholar
Blichert-Toft, J and Albarede, F (1997) The Lu–Hf isotope geochemistry of chondrites and the evolution of the mantle-crust system. Earth and Planetary Science Letters 148, 243–58.CrossRefGoogle Scholar
Burgess, SD and Bowring, SA (2015) High-precision geochronology confirms voluminous magmatism before, during, and after Earth’s most severe extinction. Science Advances 1, 114.CrossRefGoogle ScholarPubMed
Burgess, SD, Bowring, SA and Shen, SZ (2014) High-precision timeline for Earth’s most severe extinction. Proceedings of the National Academy of Sciences 111, 3316–21.CrossRefGoogle ScholarPubMed
Cai, J-X and Zhang, K-J (2009) A new model for the Indochina and South China collision during the Late Permian to the Middle Triassic. Tectonophysics 467, 3543.CrossRefGoogle Scholar
Chen, ZQ, Algeo, TJ and Bottjer, DJ (2014) Global review of the Permian–Triassic mass extinction and subsequent recovery: part I. Earth-Science Reviews 137, 15.CrossRefGoogle Scholar
Cheng, H, King, RL, Nakamura, E, Vervoort, JD, Zheng, YF, Ota, T, Wu, YB, Kobayashi, K and Zhou, ZY (2009) Transitional time of oceanic to continental subduction in the Dabie orogen: constraints from U-Pb, Lu-Hf, Sm-Nd and Ar-Ar multichronometric dating. Lithos 110, 327–42.CrossRefGoogle Scholar
Cheng, H, Zhang, C, Vervoort, JD, Wu, YB, Zheng, YF, Zheng, S and Zhou, ZY (2011) New Lu–Hf geochronology constrains the onset of continental subduction in the Dabie orogen. Lithos 121, 4154.CrossRefGoogle Scholar
Chu, NC, Taylor, RN, Chavagnac, V, Nesbitt, RW, Boella, RM, Milton, JA, German, CR, Bayon, G and Burton, K (2002) Hf isotope ratio analysis using multi-collector inductively coupled plasma mass spectrometry: an evaluation of isobaric interference corrections. Journal of Analytical Atomic Spectrometry 17, 1567–74.CrossRefGoogle Scholar
Clark, DL, Wang, CY, Orth, CJ and Gilmore, JS (1986) Conodont survival and low iridium abundances across the Permian–Triassic boundary in South-China. Science 233, 984–6.CrossRefGoogle ScholarPubMed
Cocks, LRM and Torsvik, TH (2013) The dynamic evolution of the Palaeozoic geography of eastern Asia. Earth-Science Reviews 117, 4079.CrossRefGoogle Scholar
Collins, WJ (2003) Slab pull, mantle convection, and Pangaean assembly and dispersal. Earth and Planetary Science Letters 205, 225–37.CrossRefGoogle Scholar
Cui, Y and Kump, LR (2015) Global warming and the end-Permian extinction event: Proxy and modeling perspectives. Earth-Science Reviews 149, 522.CrossRefGoogle Scholar
Dai, JG, Wang, CS, Hourigan, J and Santosh, M (2013) Multi-stage tectono-magmatic events of the Eastern Kunlun Range, northern Tibet: Insights from U–Pb geochronology and (U–Th)/He thermochronology. Tectonophysics 599, 97106.CrossRefGoogle Scholar
Ding, QF, Liu, F and Yan, W (2015) Zircon U–Pb geochronology and Hf isotopic constraints on the petrogenesis of Early Triassic granites in the Wulonggou area of the Eastern Kunlun Orogen, Northwest China. International Geology Review 57, 1735–54.CrossRefGoogle Scholar
Domeier, M and Torsvik, TH (2014) Plate tectonics in the late Paleozoic. Geoscience Frontiers 5, 303–50.CrossRefGoogle Scholar
Dong, YP and Santosh, M (2016) Tectonic architecture and multiple orogeny of the Qinling Orogenic Belt, Central China. Gondwana Research 29, 140.CrossRefGoogle Scholar
Elhlou, S, Belousova, E, Griffin, WL, Pearson, NJ and O’Reilly, SY (2006) Trace element and isotopic composition of GJ-red zircon standard by laser ablation. Geochimica et Cosmochimica Acta 70, A158.CrossRefGoogle Scholar
Enkin, RJ, Yang, Z, Chen, Y and Courtillot, V (1992) Paleomagnetic constraints on the geodynamic history of the major blocks of China from Permian to the present. Journal of Geophysical Research 97, 13953–89.CrossRefGoogle Scholar
Faure, M, Lepvrier, C, Nguyen, VV, Vu, TV, Lin, W and Chen, Z (2014) The South China block-Indochina collision: Where, when, and how? Journal of Asian Earth Sciences 79, 260–74.CrossRefGoogle Scholar
Feng, QL and Algeo, TJ (2014) Evolution of oceanic redox conditions during the Permo–Triassic transition: evidence from deepwater radiolarian facies. Earth-Science Reviews 137, 3451.CrossRefGoogle Scholar
Feng, ZZ, Yang, YQ, Jin, ZK, He, YB, Wu, SH, Xin, WJ, Bao, ZD and Tan, J (1996b) Lithofacies paleogeography of the Permian of South China. Acta Sedimentologica Sinica 14, 111 (in Chinese with English abstract).Google Scholar
Feng, QL, Du, YS, Yin, HF, Sheng, JH and Xu, JF (1996a) Carboniferous radiolaria fauna firstly discovered in Mian-Lüe ophiolitic mélange belt of South Qinling Mountains. Science in China (Series D) 39, 8792.Google Scholar
Gao, Q, Chen, ZQ, Zhang, N, Griffin, WL, Xia, W, Wang, G, Jiang, T, Xia, X and O’Reilly, SY (2015) Ages, trace elements and Hf-isotopic compositions of zircons from claystones around the Permian–Triassic boundary in the Zunyi Section, South China: implications for nature and tectonic setting of the volcanism. Journal of Earth Science 26, 872–82.CrossRefGoogle Scholar
Gao, Q, Zhang, N, Xia, W, Feng, Q, Chen, ZQ, Zheng, J, Griffin, WL, O’Reilly, SY, Pearson, NJ, Wang, G, Wu, S, Zhong, W and Sun, X (2013) Origin of volcanic ash beds across the Permian–Triassic boundary, Daxiakou, South China: petrology and U-Pb age, trace elements and Hf-isotope composition of zircon. Chemical Geology 360–361, 4153.CrossRefGoogle Scholar
Gao, XY, Zheng, YF and Chen, YX (2011) U-Pb ages and trace elements in metamorphic zircon and titanite from UHP eclogite in the Dabie orogen: constraints on P–T–t path. Journal of Metamorphic Geology 29, 721–40.CrossRefGoogle Scholar
Golonka, J (2007) Late Triassic and Early Jurassic palaeogeography of the world. Palaeogeography, Palaeoclimatology, Palaeoecology 244, 297307.CrossRefGoogle Scholar
Golonka, J, Krobicki, M, Pająk, J, Nguyen, VG and Zuchiewicz, W (2006) Global Plate Tectonics and Paleogeography of Southeast Asia. Faculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, 128 pp.Google Scholar
Gradstein, FM, Ogg, JG, Schmitz, MD and Ogg, G (2012) The Geologic Time Scale 2012. Amsterdam: Elsevier, 1176 pp.Google Scholar
Griffin, WL, Pearson, NJ, Belousova, EA, Jackson, SE, van Achterbergh, E, O’Reilly, SY and Shee, SR (2000) The Hf isotope composition of cratonic mantle: LA-MC-ICPMS analysis of zircon megacrysts in kimberlites. Geochimica et Cosmochimica Acta 64, 133–47.CrossRefGoogle Scholar
Griffin, WL, Wang, X, Jackson, SE, Pearson, NJ and O’Reilly, SY (2002) Zircon chemistry and magma mixing, SE China: in-situ analysis of Hf isotopes, Tonglu and Pingtan igneous complexes. Lithos 61, 237–69.CrossRefGoogle Scholar
Grimes, CB, John, BE, Kelermen, PB, Mazdab, FK, Wooden, JL, Cheadle, MJ, Hanghoj, K and Schwartz, JJ (2007) Trace element chemistry of zircons from oceanic crust: a method for distinguishing detrital zircon provenance. Geology 35, 643–6.CrossRefGoogle Scholar
Guo, X, Yan, Z, Wang, Z, Wang, T, Hou, K, Fu, C and Li, J (2012) Middle-Triassic arc magmatism along the northeastern margin of the Tibet: U-Pb and Lu-Hf zircon characterization of the Gangcha complex in the West Qinling terrane, central China. Journal of Geological Society, London 169, 327–36.CrossRefGoogle Scholar
He, B, Xu, Y, Chung, SL, Xiao, L and Wang, Y (2003) Sedimentary evidence for a rapid, kilometer-scale crustal doming prior to the eruption of the Emeishan flood basalts. Earth and Planetary Science Letters 213, 391405.CrossRefGoogle Scholar
He, B, Zhong, YT, Xu, YG and Li, XH (2014) Triggers of Permo-Triassic boundary mass extinction in South China: The Siberian Traps or Paleo-Tethys ignimbrite flare-up? Lithos 204, 258–67.CrossRefGoogle Scholar
He, BH (2016) Research progress on some issues on the Emeishan Large Igneous Province. Advances in Earth Science 31, 2342 (in Chinese with English abstract).Google Scholar
He, JW, Chai, ZF and Ma, SL (1989) Discovery of paramorph of high-quartz in the stratotype section of the Permian–Triassic boundary at Meishan of Changxing, Zhejiang, and its significance. Chinese Science Bulletin 34, 474–7.Google Scholar
Hong, HL, Zhang, N, Li, ZH, Xue, HJ, Xia, WC and Yu, N (2008) Clay mineralogy across the P–T boundary of the Xiakou section, China: evidence of clay provenance and environment. Clays and Clay Minerals 56, 131–43.CrossRefGoogle Scholar
Hou, KJ, Li, YH, Zou, TR, Qu, XM, Shi, YR and Xie, GQ (2007) Laser ablation-MC-ICP-MS technique for Hf isotope microanalysis of zircon and its geological applications. Acta Petrologica Sinica 23, 2595–604 (in Chinese with English abstract).Google Scholar
Huang, BC, Yan, YG, Piper, JDA, Zhang, DH, Yi, ZY, Yu, S and Zhou, TH (2018) Paleomagnetic constraints on the paleogeography of the East Asian blocks during Late Paleozoic and Early Mesozoic times. Earth-Science Reviews 186, 836.CrossRefGoogle Scholar
Huang, H, Niu, YL, Nowell, G, Zhao, ZD, Yu, XH, Zhu, DC, Mo, XX and Ding, S (2014) Geochemical constraints on the petrogenesis of granitoids in the East Kunlun Orogenic belt, northern Tibetan Plateau: implications for continental crust growth through syn-collisional felsic magmatism. Chemical Geology 370, 118.CrossRefGoogle Scholar
Iizuka, T and Hirata, T (2005) Improvements of precision and accuracy in in situ Hf isotope microanalysis of zircon using the laser ablation-MC-ICPMS technique. Chemical Geology 220, 121–37.CrossRefGoogle Scholar
Isozaki, Y (2009) Integrated “plume winter” scenario for the double-phased extinction during the Paleozoic-Mesozoic transition: The G-LB and P-TB events from a Panthalassan perspective. Journal of Asian Earth Sciences 36, 459–80.CrossRefGoogle Scholar
Isozaki, Y, Shimizu, N, Yao, J, Ji, Z and Matsuda, T (2007) End-Permian extinction and volcanism-induced environmental stress: Permian–Triassic boundary interval of a lower-slope facies at Chaotian, South China. Palaeogeography, Palaeoclimatology, Palaeoecology 252, 218–38.CrossRefGoogle Scholar
Joachimski, MM, Lai, X, Shen, S, Jiang, H, Luo, G, Chen, B, Chen, J and Sun, Y (2012) Climate warming in the latest Permian and the Permian–Triassic mass extinction. Geology 40, 195–8.CrossRefGoogle Scholar
Li, GJ, Wang, QF, Yu, L, Hu, ZC, Ma, N and Huang, YH (2013) Closure time of the Ailaoshan Paleo-Tethys Ocean: Constraints from the zircon U-Pb dating geochemistry of the Late Permian granitoids. Acta Petrologica Sinica 29, 3883–900 (in Chinese with English abstract).Google Scholar
Li, SG, Hou, ZH, Yang, YC, Sun, WD, Zhang, GW and Li, QL (2004) Timing and geochemistry characters of the Sanchazi magmatic arc in Mianlüe tectonic zone, South Qinling. Science in China (Series D) 47, 317–28.CrossRefGoogle Scholar
Liao, Z, Hu, W, Cao, J, Wang, X, Yao, S and Wan, Y (2016a) Permian–Triassic boundary (PTB) in the Lower Yangtze Region, southeastern China: a new discovery of deep-water archive based on organic carbon isotopic and U–Pb geochronological studies. Palaeogeography, Palaeoclimatology, Palaeoecology 451, 124–39.CrossRefGoogle Scholar
Liao, Z, Hu, W, Wang, X, Cao, J, Yao, S and Wan, Y (2016b) Volcanic origin of claystone near the Permian-Triassic boundary in the deep water environment of the Lower Yangtze region and its implications for LPME. Acta Geologica Sinica 90, 785800 (in Chinese with English abstract).Google Scholar
Liu, FL and Liou, JG (2011) Zircon as the best mineral for P–T–time history of UHP metamorphism: a review on mineral inclusions and U-Pb SHRIMP ages of zircons from the Dabie-Sulu UHP rocks. Journal of Asian Earth Sciences 40, 139.CrossRefGoogle Scholar
Liu, HC, Wang, YJ, Cawood, PA, Fan, WM, Cai, YF and Xing, XW (2015) Record of Tethyan ocean closure and Indosinian collision along the Ailaoshan suture zone (SW China). Gondwana Research 27, 1292–306.CrossRefGoogle Scholar
Liu, HC, Wang, YJ, Li, ZH, Zi, JW and Huangfu, PP (2018) Geodynamics of the Indosinian orogeny between the South China and Indochina blocks: insights from latest Permian–Triassic granitoids and numerical modeling. Geological Society of America Bulletin 130, 1289–306.CrossRefGoogle Scholar
Liu, XC, Jahn, BM, Dong, SW, Lou, YX and Cui, JJ (2008) High-pressure metamorphic rocks from Tongbaishan, central China: U-Pb and 40Ar/39Ar age constraints on the provenance of protoliths and timing of metamorphism. Lithos 105, 301–18.CrossRefGoogle Scholar
Liu, XC, Wu, YB, Gao, S, Wang, J, Peng, M, Gong, HJ, Liu, YS and Yuan, HL (2011) Zircon U-Pb and Hf evidence for coupled subduction of oceanic and continental crust during the Carboniferous in the Huwan shear zone, western Dabie orogen, central China. Journal of Metamorphic Geology 29, 233–49.CrossRefGoogle Scholar
Ludwig, KR (2012) Isoplot 3.75: A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Centre, Berkeley, Special Publication no. 5, 75 pp.Google Scholar
Meng, E, Liu, FL, Liu, PH, Liu, CH, Yang, H, Wang, F, Shi, JR and Cai, J (2014) Petrogenesis and tectonic significance of Paleoproterozoic meta-mafic rocks from central Liaodong Peninsula, northeast China: Evidence from zircon U–Pb dating and in situ Lu–Hf isotopes, and whole-rock geochemistry. Precambrian Research 247, 92109.CrossRefGoogle Scholar
Metcalfe, I (1996) Pre-Cretaceous evolution of SE Asian terranes. In Tectonic Evolution of Southeast Asia (eds Hall, R and Blundell, D), pp. 97122. Geological Society of London, Special Publication no. 106.Google Scholar
Metcalfe, I (2009) Late Palaeozoic and Mesozoic tectonic and palaeogeographical evolution of SE Asia. In Late Palaeozoic and Mesozoic Ecosystems in SE Asia (eds Buffetaut, E, Cuny, G, Le Loeuff, J and Suteethorn, V), pp. 723. Geological Society of London, Special Publication no. 315.Google Scholar
Metcalfe, I (2013) Gondwana dispersion and Asian accretion: Tectonic and palaeogeographic evolution of eastern Tethys. Journal of Asian Earth Sciences 66, 133.CrossRefGoogle Scholar
Murphy, BJ and Nance, D (2008) The Pangea conundrum. Geology 36, 703–6.CrossRefGoogle Scholar
Ren, HD, Wang, T, Zhang, L, Wang, XX, Huang, H, Feng, CY, Teschner, C and Song, P (2016) Age, sources and tectonic setting of the Triassic igneous rocks in the easternmost segment of the East Kunlun Orogen, Central China. Acta Geologica Sinica (English Edition) 90, 641–68.Google Scholar
Retallack, GJ (2013) Permian and Triassic greenhouse crises. Gondwana Research 24, 90103.CrossRefGoogle Scholar
Retallack, GJ and Jahren, AH (2008) Methane release from igneous intrusion of coal at the Permian–Triassic boundary. Journal of Geology 116, 120.CrossRefGoogle Scholar
Rubatto, D (2002) Zircon trace element geochemistry: partitioning with garnet and the link between U-Pb ages and metamorphism. Chemical Geology 184, 123–38.CrossRefGoogle Scholar
Scotese, CR (2004) A continental drift flipbook. The Journal of Geology 112, 729–41.CrossRefGoogle Scholar
Scotese, CR and McKerrow, WS (1990) Revised world maps and introduction. In Palaeozoic Palaeogeography and Biogeography (eds McKerrow, WS and Scotese, CR), pp. 121. Geological Society of London, Memoir no. 12.Google Scholar
Shellnutt, JG, Wang, CY, Zhou, MF and Yang, Y (2009) Zircon Lu-Hf isotopic compositions of metaluminous and peralkaline A-type granitic plutons of the Emeishan large igneous provence (SW China): constraints on the mantle plume. Journal of Asian Earth Sciences 35, 4555.CrossRefGoogle Scholar
Shen, J, Algeo, TJ, Feng, QL, Zhou, L, Feng, LP, Zhang, N and Huang, JH (2013) Volcanically induced environmental change at the Permian–Triassic boundary (Xiakou, Hubei Province, South China): related to West Siberian coal-field methane releases? Journal of Asian Earth Sciences 75, 95109.CrossRefGoogle Scholar
Shen, J, Algeo, TJ, Hu, Q, Zhang, N, Zhou, L, Xia, WC, Xie, SC and Feng, QL (2012) Negative C-isotope excursions at the Permian–Triassic boundary linked to volcanism. Geology 40, 963–66.CrossRefGoogle Scholar
Shen, J, Feng, Q, Algeo, TJ, Li, C, Planavsky, NJ, Zhou, L and Zhang, M (2016) Two pulses of oceanic environmental disturbance during the Permian–Triassic boundary crisis. Earth and Planetary Science Letters 443, 139–52.CrossRefGoogle Scholar
Shen, SZ, Crowley, JL, Wang, Y, Bowring, SA, Erwin, DH, Sadler, PM, Cao, CQ, Rothman, DH, Henderson, CM, Ramezani, J, Zhang, H, Shen, Y, Wang, XD, Wang, W, Mu, L, Li, WZ, Tang, YG, Liu, XL, Liu, LJ, Zeng, Y, Jiang, YF and Jin, YG (2011a) Calibrating the end-Permian mass extinction. Science 334, 1367–72.CrossRefGoogle ScholarPubMed
Shen, WJ, Sun, YG, Lin, YT, Liu, DT and Chai, PX (2011b) Evidence for wildfire in the Meishan section and implications for Permian–Triassic events. Geochimica et Cosmochimica Acta 75, 19922006.CrossRefGoogle Scholar
Shnukov, SE, Andreev, AV and Savenok, SP (1997) Admixture elements in zircons and apatite: a tool for provenances studies of terrigenous sedimentary rocks. In Proceedings of the Ninth European Union of Geosciences Meeting (EUG 9), 23–23 March 1997, Strasbourg, Abstract 65/4P 16:597.Google Scholar
Smith, AG and Livermore, RA (1991) Pangea in Permian to Jurassic time. Tectonophysics 187, 135–79.CrossRefGoogle Scholar
Spörli, B, Aita, Y, Hori, RS and Takemura, A (2007) Results of multidisciplinary studies of the Permian/Triassic ocean floor sequence (Waipapa Terrane) at Arrow Rocks in the framework of paleomagnetism in Pre-Neogene rocks from New Zealand. In The Oceanic Permian/Triassic Boundary Sequence at Arrow Rocks (Oruatemanu), Northland (eds Spörli, B, Takemura, A and Hori, RS), pp. 219229. New Zealand: GNS Science Monograph, no. 24.Google Scholar
Stampfli, GM, Hochard, C, Vérard, C, Wilhem, C and von Raumer, J (2013) The formation of Pangea. Tectonophysics 593, 119.CrossRefGoogle Scholar
Sun, WD, Williams, IS and Li, SG (2002) Carboniferous and Triassic eclogites in the western Dabie Mountains, east-central China: evidence for protracted convergence of the North and South China Blocks. Journal of Metamorphic Geology 20, 873–86.CrossRefGoogle Scholar
Sun, YD, Joachimski, MM, Wignall, PB, Yan, CB, Chen, YL, Jiang, HS, Wang, LN and Lai, XL (2012) Lethally hot temperatures during the early Triassic greenhouse. Science 388, 366–70.CrossRefGoogle Scholar
Svensen, H, Planke, S, Polozov, AG, Schmidbauer, N, Corfu, F, Podladchikov, YY and Jamtveit, B (2009) Siberian gas venting and the end-Permian environmental crisis. Earth and Planetary Science Letters 277, 490500.CrossRefGoogle Scholar
Taylor, SR and McLennan, SM (1981) The composition and evolution of the continental crust—rare-earth element evidence from sedimentary-rocks. Philosophical Transactions of the Royal Society of London Series A – Mathematical Physical and Engineering Sciences 301, 381–99.Google Scholar
van der Meer, DG, Spakman, W, van Hinsbergen, DJJ, Amaru, ML and Torsvik, TH (2010) Towards absolute plate motions constrained by lower-mantle slab remnants. Nature Geoscience 3, 3640.CrossRefGoogle Scholar
Wang, XX, Wang, T and Zhang, CL (2015) Granitoid magmatism in the Qinling orogen, central China and its bearing on orogenic evolution. Science China: Earth Sciences 58, 1497–512.CrossRefGoogle Scholar
Wignall, PB (2001) Large igneous provinces and mass extinctions. Earth-Science Reviews 53, 133.CrossRefGoogle Scholar
Wu, FY, Yang, YH and Xie, LW (2006) Hf isotopic compositions of standard zircons and baddeleyites used in U–Pb geochronology. Chemical Geology 231, 105–26.CrossRefGoogle Scholar
Wu, YB, Hanchar, JM, Gao, S, Sylvester, PJ, Tubrett, M, Qiu, HN, Wijbrans, JR, Brouwer, FM, Yang, SH, Yang, QJ, Liu, YS and Yuan, HL (2009) Age and nature of eclogites in the Huwan shear zone, and the multi-stage evolution of the Qinling-Dabie-Sulu orogen, central China. Earth and Planetary Science Letters 277, 345–54.CrossRefGoogle Scholar
Xiao, WJ, Windley, BF, Hao, J and Li, JL (2002) Arc-ophiolite obduction in the Western Kunlun Range (China): implications for the Palaeozoic evolution of central Asia. Journal of the Geological Society of London 159, 517–28.CrossRefGoogle Scholar
Xu, L, Lin, Y, Shen, W, Qi, L, Xie, L and Ouyang, Z (2007) Platinum-group elements of the Meishan Permian–Triassic boundary section: evidence for flood basaltic volcanism. Chemical Geology 246, 5564.CrossRefGoogle Scholar
Xu, YG, Luo, ZY, Huang, XL, He, B, Xiao, L, Xie, LW and Shi, YR (2008) Zircon U–Pb and Hf isotope constraints on crustal melting associated with the Emeishan mantle plume. Geochimica et Cosmochimica Acta 72, 3084–104.CrossRefGoogle Scholar
Yan, Z, Bian, QT, Korchagin, OA, Pospelov, II, Li, JL and Wang, ZQ (2008) Provenance of Early Triassic Hongshuichuan Formation in the southern margin of the East Kunlun Mountains: Constrains from detrital framework, heavy mineral analysis and geochemistry. Acta Petrologica Sinica 24, 1068–78 (in Chinese with English abstract).Google Scholar
Yan, Z, Guo, X, Fu, C, Aitchison, J, Wang, Z and Li, J (2014) Detrital heavy mineral constraints on the Triassic tectonic evolution of the West Qinling terrane, NW China: Implications for understanding subduction of the Paleotethyan Ocean. The Journal of Geology 122, 591608.CrossRefGoogle Scholar
Yan, Z, Wang, ZQ, Li, JL, Xu, ZQ and Deng, JF (2012) Tectonic settings and accretionary orogenesis of the West Qinling Terrane, northeastern margin of the Tibet Plateau. Acta Petrologica Sinica 28, 1808–28 (in Chinese with English abstract).Google Scholar
Yang, JH, Cawood, PA, Du, YS, Huang, H, Huang, HW and Tao, P (2012) Large Igneous Province and magmatic arc sourced Permian–Triassic volcanogenic sediments in China. Sedimentary Geology 261, 120–31.CrossRefGoogle Scholar
Yang, ZY, Ma, XH, Huang, BC, Sun, ZM and Zhou, YX (1998) Apparent polar wander path and tectonic movement of the North China Block in Phanerozoic. Science in China (Series D) 41, 5165.Google Scholar
Yang, ZY, Wu, SB, Yin, HF, Xu, GR, Zhang, KX and Bi, XM (1991) Geological Events of Permo-Triassic Transitional Period in South China. Beijing: Geological Publishing House, 190 pp. (in Chinese with English abstract).Google Scholar
Yin, HF, Feng, QL, Lai, XL, Baud, A and Tong, JN (2007) The protracted Permo-Triassic crisis and multi-episode extinction around the Permian–Triassic boundary. Global and Planetary Change 55, 120.CrossRefGoogle Scholar
Yin, HF, Huang, SJ, Zhang, KX, Hansen, HJ, Yang, FQ, Ding, MH and Bie, X (1992) The effects of volcanism on the Permo-Triassic mass extinction in South China. In Permo-Triassic events in the eastern Tethys: stratigraphy, classification, and relations with the Western Tethys (eds Sweet, WC, Yang, ZY, Dickins, JM and Yin, HF), pp. 146–57. Cambridge: Cambridge University Press.Google Scholar
Yin, HF, Huang, SJ, Zhang, KX, Yang, FQ, Ding, MH, Bi, XM and Zhang, SX (1989) Volcanism at the Permian–Triassic boundary in South China and its effects on mass extinction. Acta Geologica Sinica (English Edition) 62, 169–81.Google Scholar
Zhang, G, Dong, Y, Lai, S, Guo, A, Meng, Q, Liu, S, Cheng, S, Yao, A, Zhang, Z, Pei, X and Li, S (2004) Mianlue tectonic zone and Mianlue suture zone on southern margin of Qinling–Dabie orogenic belt. Science in China (Series D) 47, 300–16.CrossRefGoogle Scholar
Zhang, ZY, He, WH, Zhang, Y, Yang, TL and Wu, SB (2009) Late Permian–earliest Triassic ammonoid sequences from the Rencunping section, Sangzhi County, Hunan Province, South China and their regional correlation. Geological Science and Technology Information 28, 2330 (in Chinese with English abstract).Google Scholar
Zhao, GC, Zhang, GW, Wang, YJ, Huang, BC, Dong, YP, Li, SZ and Yu, S (2018) Geological reconstructions of the East Asian blocks: from the breakup of Rodinia to the assembly of Pangea. Earth-Science Reviews 186, 262–86.CrossRefGoogle Scholar
Zhao, XX and Coe, RS (1987) Palaeomagnetic constraints on the collision and rotation of North and South China. Nature 327, 141–4.CrossRefGoogle Scholar
Zheng, B, Mou, C, Wang, X, Xiao, Z and Chen, Y (2019) Sedimentary record of the collision of the North and South China cratons: new insights from the Western Hubei Trough. Geological Journal 54(6), 3335–48.Google Scholar
Zhong, H, Campbell, IH, Zhu, WG, Allen, CM, Hu, RZ, Xie, LW and He, DF (2011) Timing and source constraints on the relationship between mafic and silicic intrusions in the Emeishan large igneous province. Geochimica et Cosmochimica Acta 75, 1374–95.CrossRefGoogle Scholar
Zhong, H, Zhu, WG, Hu, RZ, Xie, LW, He, DF, Liu, F and Chu, ZY (2009) Zircon U–Pb age and Sr–Nd–Hf isotope geochemistry of the Panzhihua A-type syenitic intrusion in the Emeishan large igneous province, southwest China and implications for growth of juvenile crust. Lithos 110, 109–28.CrossRefGoogle Scholar
Zhu, J, Zhang, ZC, Hou, T and Kang, JL (2011) LA-ICP-MS zircon U-Pb geochronology of the tuffs on the uppermost of the Emeishan basalt succession in Panxian County, Guizhou Province: Constraints on genetic link between Emeishan large igneous province and the mass extinction. Acta Petrologica Sinica 27, 2743–51 (in Chinese with English abstract).Google Scholar
Zhu, RX, Yang, ZY, Wu, HN, Ma, XH, Huang, BC, Meng, ZF and Fang, DJ (1998) Paleomagnetic constraints on the tectonic history of the major blocks of China during the Phanerozoic. Science in China (Series D) 41, 119.Google Scholar
Zi, JW, Cawood, PA, Fan, WM, Tohver, E, Wang, YJ and McCuaig, TC (2012) Generation of early Indosinian enriched mantle-derived granitoid pluton in the Sanjiang Orogen (SW China) in response to closure of the Paleo-Tethys. Lithos 140–141, 166–82.CrossRefGoogle Scholar
Figure 0

Fig. 1. Distribution of PTB volcanic ash beds in South China (upper part) and correlation of representative PTB sections (lower part). The semitransparent areas in the upper map represent the distribution of volcanic ash beds, and n represents the number of sections. Volcanic ash bed localities and lithological columns are compiled from Yin et al. (1989), Yang et al. (1991, 2012), Shen et al. (2011a), Zhu et al. (2011), Gao et al. (2013, 2015), Burgess et al. (2014), He et al. (2014), Liao et al. (2016a, b), Baresel et al. (2017) and the SHP section in this study. Tectonic boundaries are from Zhang et al. (2004).

Figure 1

Fig. 2. (a) Global palaeogeography at PTB (modified from Spörli et al.2007). (b) Changhsingian palaeogeography of South China (modified from Feng et al.1996b; Feng & Algeo, 2014). 1 – land; 2 – continental facies; 3 – littoral detrital facies; 4 – shallow-water carbonate; 5 –deep-water chert-mudstone; NCC – North China Craton; SCC – South China Craton; SHP – Shuanghe Poumian.

Figure 2

Fig. 3. Lithologic column of the SHP section and sample locations.

Figure 3

Fig. 4. The late Permian – Early Triassic succession of the study area (after Zhang et al.2009; Zheng et al.2019). The ages of the succession are from Gradstein et al. (2012).

Figure 4

Fig. 5. Outcrop photographs of the studied volcanic ash beds in the SHP section: (a, b) bed 1 (sample ZC) and (c, d) bed 3 (sample ZG).

Figure 5

Fig. 6. Representative zircon CL images of our samples and their U–Pb ages and εHf(t) values. Circles represent laser pits.

Figure 6

Fig. 7. Zircon U–Pb concordia plots of samples (data-point error ellipses are 2σ).

Figure 7

Fig. 8. Chondrite-normalized REE patterns for zircons. Chondritic values used for normalization are from Taylor & McLennan (1981). Curves represent zircons from the SHP section. Shaded areas are compiled from other PTB volcanic ash beds in South China (Yang et al.2012; Gao et al.2013, 2015).

Figure 8

Fig. 9. εHf(t) plots for zircons: (a) from the SHP section; and (b) of age c. 240–270 Ma different PTB sections in South China. Daxiakou section is from Gao et al. (2013), Zunyi section is from Gao et al. (2015), Meishan section, Chaotian section, Shangsi section and Dongpan section are from He et al. (2014).

Figure 9

Fig. 10. Trace-element diagrams for source rock and tectonic setting discrimination of the zircons aged c. 240–270 Ma. (a–c) Y versus U, Y versus (Yb/Sm)N and Hf versus Y diagrams for source-rock discrimination (Shnukov et al.1997; Belousova et al.2002), where subscript N represents chondrite-normalized value; I – kimberlites; II – ultramafic, mafic and intermediate rocks; III – quartz-bearing intermediate and felsic rocks; IV – felsic rocks with high SiO2 content; V – greisens; VI – alkaline rocks and alkaline metasomatites of alkaline complexes; VII – carbonatites. (d) U/Yb versus Y diagram for tectonic setting discrimination (Grimes et al.2007; Gao et al.2013). The red circle represents zircons from felsic rocks at convergent continental margins before post-collisional extension. The shaded area represents data compiled from other PTB volcanic ash beds in South China (after Yang et al.2012; Gao et al.2013, 2015).

Figure 10

Fig. 11. THf2 ages of zircons from different PTB volcanic ash beds in South China. Daxiakou section is from Gao et al. (2013), Zunyi section is from Gao et al. (2015), and Meishan, Chaotian, Shangsi and Dongpan sections are from He et al. (2014).

Figure 11

Fig. 12. Late Permian palaeogeography map of the Palaeotethys region showing the convergent continental margins around South China (modified from Huang et al.2018). Detailed palaeogeography of South China Craton is shown in Figure 2b.

Figure 12

Fig. 13. Zircon εHf(t) value and THf2 age histograms of PTB ash beds in South China and late Permian – Early Triassic intermediate to felsic magmatic rocks in Simao–Indochina and East Kunlun convergent continental margins. Data for South China PTB ash beds are compiled from Gao et al. (2013, 2015) and He et al. (2014). Data for Simao–Indochina convergent continental margin are compiled from Zi et al. (2012), Li et al. (2013) and Liu et al. (2015). Data for East Kunlun convergent continental margin are compiled from Huang et al. (2014), Ding et al. (2015) and Ren et al. (2016).

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