Neoproterozoic peraluminous granites in the western margin of the Yangtze Block, South China: Implications for the reworking of mature continental crust

Journal Pre-proofs Neoproterozoic peraluminous granites in the western margin of the Yangtze Block, South China: Implications for the reworking of mature continental crust Yu Zhu, Shaocong Lai, Jiangfeng Qin, Renzhi Zhu, Fangyi Zhang, Zezhong Zhang, Shaowei Zhao PII: DOI: Reference:

S0301-9268(19)30217-7 https://doi.org/10.1016/j.precamres.2019.105443 PRECAM 105443

To appear in:

Precambrian Research

Received Date: Revised Date: Accepted Date:

13 April 2019 28 August 2019 30 August 2019

Please cite this article as: Y. Zhu, S. Lai, J. Qin, R. Zhu, F. Zhang, Z. Zhang, S. Zhao, Neoproterozoic peraluminous granites in the western margin of the Yangtze Block, South China: Implications for the reworking of mature continental crust, Precambrian Research (2019), doi: https://doi.org/10.1016/j.precamres.2019.105443

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

© 2019 Published by Elsevier B.V.

Neoproterozoic peraluminous granites in the western margin of the Yangtze Block, South China: Implications for the reworking of mature continental crust Yu Zhua, Shaocong Lai*a, Jiangfeng Qina, Renzhi Zhua, Fangyi Zhanga, Zezhong Zhanga, Shaowei Zhaob

a

State Key Laboratory of Continental Dynamics, Department of Geology,

Northwest University, Xi’an 710069, China.

b

Ministry of Education, Key Laboratory of Western China's Mineral

Resources and Geological Engineering, School of Earth Science & Resources, Chang'an University, Xi'an 710054, China

*Corresponding author. Tel.: +86 29 88307610 Email address: [email protected]

Abstract: Significant widespread melting of the mantle and juvenile mafic lower crust is known to have occurred along the western margin of the Yangtze Block during the Neoproterozoic, but melting of the mature continental crust remains poorly understood. Peraluminous granites can provide vital insights on the reworking of mature continental crustal materials. We present zircon U-Pb-Hf isotopic, whole-rock geochemical, and Sr-Nd isotopic data from the Neoproterozoic peraluminous granites in the western Yangtze Block, South China. Zircon U-Pb dating displays concordant crystallization ages of ca. 840 Ma for the Kuanyu granites and ca. 835 Ma for the Cida granites. These peraluminous granites have high SiO2 (66.9–75.6 wt.%), K2O (4.61–7.29 wt.%) contents, as well as high K2O/Na2O (1.44–3.25) and A/CNK (molar ratio of Al2O3/(CaO + Na2O + K2O)) (1.04–1.18) ratios. The samples are enriched in Rb, K, Th, U, and Pb, and depleted in Nb, Ta, Ba, Sr, and Ti, indicating a middle-upper crustal affinity. They are also characterized by high (87Sr/86Sr)i (0.7099–0.7217) and negative εNd(t) values (−5.1 to −2.9), which resemble the isotopic features of an evolved continental crust source. Furthermore, these peraluminous granites possess variable CaO/Na2O (0.09–0.65) and Al2O3/TiO2 (25.3–88.4) ratios, moderate Rb/Ba (1.68–3.86) and Rb/Sr (0.32–0.85) ratios, as well as high molar Al2O3/(MgO + FeOT) (2.04–5.23) and low molar CaO/(MgO + FeOT) (0.15–0.48), implying that they predominantly originate from heterogeneous metasedimentary sources

(metapelites + metagreywackes). Scarce evidence of hybridization processes between crust- and mantle-derived components indicates that their heterogeneous zircon Hf isotopic compositions (εHf(t) = −7.75 to +3.31) may be

caused

by

disequilibrium

partial

melting

of

heterogeneous

metasedimentary sources, similar to peraluminous granites from the Altai area and Jiangnan orogen in China. In combination with previously reported results, we suggest that the Kuanyu and Cida peraluminous granites represent melting of mature crustal material in an evolved middle-upper crust source during the early stages of the Neoproterozoic subduction process. The western margin of the Yangtze Block underwent not only melting of the juvenile mafic lower crust but also reworking of the mature continental crust during the Neoproterozoic. Keywords: Peraluminous granites; Neoproterozoic; Petrogenesis; Mature crust melting; Disequilibrium melting; Yangtze Block

1. Introduction The South China Block (SCB) is composed of the Yangtze Block to the northwest and the Cathaysia Block to the southeast (Wang et al., 2013; Zhao and Cawood, 2012; Zhao et al., 2018), and preserves extensive Neoproterozoic magmatism generated during the assembly and breakup of the Rodinia supercontinent (Li et al., 2003, 2006; Zhou et al., 2002, 2006a, 2006b; Zhao et al., 2013, 2017, 2018). The Neoproterozoic magmatism is characterized by voluminous felsic intrusions and some mafic-ultramafic

intrusions around the Yangtze Block (Zhou et al., 2002, 2006a, 2006b; Zhao et al., 2008a, 2013, 2018). Previous studies mainly considered these intrusions to have resulted from either a mantle plume upwelling (Li et al., 2003, 2006), lithospheric extension in response to plate-rift process (Zheng et al., 2007), or persistent subduction process (Zhou et al., 2002, 2006a, 2006b; Zhao et al., 2018 and references therein). On the western margin of the Yangtze Block, Neoproterozoic massive mafic to intermediate, adakitic, and Na-rich granitic rocks have been investigated to evaluating the crustal evolution, mantle melting and fractionation during the last decade years (Du et al., 2014; Lai et al., 2015a, 2015b; Li and Zhao, 2018; Sun et al., 2007; Zhao et al., 2008a, 2008b, 2010; Zhao and Cawood, 2012; Zhou et al., 2002, 2006a, 2006b; Zhu et al., 2019a, 2019b). The ca. 860–740 Ma mafic-intermediate rocks are dominantly considered to be from a mantle source metasomatized by subduction-related fluids and/or melts (Du et al., 2014; Sun and Zhou, 2008; Zhao et al., 2008a; Zhao and Zhou, 2007a; Zhou et al., 2006b). The ca. 800–750 Ma adakitic rocks have been explained as the products of a subducted oceanic slab (Zhao and Zhou, 2007b; Zhou et al., 2006a) or thickened continental lower crust (Huang et al., 2009; Zhu et al., 2019b). In addition, the ca. 800–750 Ma Na-rich granitoids are thought to have been produced by partial melting of juvenile mafic lower crust (Lai et al., 2015a; Zhao et al., 2008b; Zhu et al., 2019a). However, few detailed studies have addressed partial melting of mature continental crust along the western

margin of the Yangtze Block. Peraluminous granites are universal in various tectonic setting and geochemically characterized by a high aluminous saturation index (ASI = molar Al2O3/(CaO + Na2O + K2O)) (A/CNK > 1.0) (Chappell and White, 1992; Chen et al., 2014; Kemp et al., 2007; Patiňo Douce, 1995; Zhao et al., 2013). Most peraluminous granites are thought to be the products of mature metasedimentary (e.g., metapelites and metagreywackes) in a relatively evolved crust source induced by mantle-derived magma (Clemens, 2003; Clemens et al., 2016; Chappell et al., 2012). Although some peraluminous granites originated from metaluminous igneous protoliths (e.g., basaltic to andesitic rocks) (Chappell and White, 1992, 2001; Chappell et al., 2012; Clemens, 2003), mature sedimentary components were also significantly incorporated into their magmatic evolution (Clemens, 2018; Chappell et al., 2012; Kemp et al., 2007; Zhao et al., 2015). Identification of the magma source of the peraluminous granites can therefore provide important insights on the melting of mature continental crustal materials. We recently identified two peraluminous granitic plutons, including the Kuanyu and Cida granites in the Miyi region along the western margin of the Yangtze Block, South China. In this study, we present new zircon U-Pb ages, whole-rock major and trace element compositions, Sr-Nd isotopic data, and in-situ zircon Lu-Hf isotopic data of these peraluminous granites. The objectives of our work are to (1) investigate the petrogenesis of

Neoproterozoic peraluminous granites and (2) identify the Neoproterozoic mature continental crustal magmatism in the western margin of the Yangtze Block that responded to early subduction process along the Rodinia supercontinent. 2. Regional geology and sample South China is divided into two large blocks by the NNE-trending, 1500-km-long Neoproterozoic Jiangnan orogenic belt (Li et al., 2008; Wang et al., 2013, 2014), which resulted from the assembly of the Yangtze and Cathaysia blocks around 830 Ma (Zhao et al., 2011) (Fig. 1). The Jiangnan orogenic belt is mainly composed of Neoproterozoic massive, undeformed granitoids and low-grade greenschist facies metamorphosed sedimentary rocks (Wang et al., 2014). The Yangtze Block is bounded by the Indochina block to the southwest and Songpan-Ganzi terrane to the west (Gao et al., 1999; Zhao and Cawood, 2012), and separated from the North China Block by the Qinling-Dabie-Sulu orogenic belt, which was generated by the Triassic collision between the North China and Yangtze blocks (Harker et al., 2006; Zhao et al., 2008a; 2013, Zheng et al., 2005) (Fig. 1). The Yangtze Block consists of Archean to Proterozoic basement overlain by Neoproterozoic (Sinian) to Cenozoic cover sequences (Li and Zhao, 2018; Zhou et al., 2002, 2006b). The Archean to Early Neoproterozoic basement complexes are composed of metamorphosed arenaceous to argillaceaous sedimentary

strata

(Zhao

et

al.,

2010).

The

Kongling

TTG

(tonalite-trondhjemite-granodiorite) suite is the only Archean terrane exposed in the Yangtze Block (Gao et al, 1999), but zircon U-Pb-Hf isotopic evidence from Paleozoic granulite xenoliths suggest that Archean crust most probably exists extensively beneath the Yangtze Block (Zheng et al., 2006). Voluminous Neoproterozoic intrusive and extrusive igneous rocks were emplaced along the western margin of the Yangtze Block (Fig. 2a) (Du et al., 2014; Li et al., 2006, Munteanu et al., 2010; Zhao et al., 2010; Zhou et al., 2002, 2006a, 2006b; Zhu et al., 2008). Neoproterozoic metamorphic complexes are well preserved and include, from north to south, the Kangding, Miyi and Yuanmou complexes whose igneous rocks have concordant crystallization ages ranging from ca. 860 to 750 Ma (Zhou et al., 2002). Neoproterozoic sequences, such as the Yanbian, Ebian, Huangshuihe Groups, and Sinian strata (Geng et al., 2008), are overlain by a thick sequence (> 9 km) of Neoproterozoic to Permian strata composed of clastic, carbonate and meta-volcanic rocks

(Zhu et al., 2008). Moreover,

Neoproterozoic volcanic-sedimentary rocks are well-known as the Yanbian, Suxiong, and Kaijianqiao groups (Sun et al., 2008). Two large serpentinite blocks associated with gabbros and pillow basalts are traditionally considered to be ophiolities in the Shimian area. These ophiolite sequences have been dated to be Late Mesoproterozoic and Early Neoproterozoic, and are geochemically similar to the SSZ(supra-subduction zone)-type ophiolites (Hu et al., 2017; Zhao et al., 2017). In the western Yangtze Block, massive

Neoproterozoic

granites

are

spatially

associated

with

high-grade

metamorphic complexes and low-grade metamorphic Mesoproterozoic strata (Zhao and Zhou, 2007a). The Miyi region is located in the southern segment of the western margin of the Yangtze Block, South China (Fig. 2a). In this area, the Late Mesoproterozoic to Neoproterozoic Huili Group is widespread and consists of meta-clastic and meta-carbonate rocks interbedded with meta-volcanic rocks of about 10 km in thickness (Zheng et al., 2007; Zhu et al., 2016). From the base upward, the Huili Group contains the Yinmin, Luoxue, Heishan, Qinglongshan, Limahe, Fengshan, and Tianbaoshan formations (SPBGMR, 1966; Zhu et al., 2016). The Huili Group was intruded by later Neoproterozoic and Triassic granitic magmatism around the Kuanyu and Cida areas. In addition, there have been reports of Neoproterozoic mafic and felsic magmatism including the ca. 803–790 Ma granites and ca. 840 Ma mafic rocks from the Xiacun and Mosuoying areas (Guo et al., 2009). In this study, we investigate the Kuanyu and Cida granitic plutons situated near the town of Huayuan, which is located at the northwest part of the Miyi County. These plutons are located on both sides of the Cida River, and tectonically bounded by several faults (Fig. 2b). The Kuanyu and Cida plutons are mainly composed of medium- to medium-coarse grain biotite granites (Figs. 3a, 3b). Samples from the Kuanyu granites consist of K-feldspar (20–30 vol%), plagioclase (20–25 vol%), quartz (20–25 vol%), biotite (10–15

vol%), and accessory minerals including magnetite (0–3 vol%) and zircon (Figs. 3c, 3e). The plagioclase typically shows polysynthetic twinning and the K-feldspar displays the distinctive crossed twinning. The biotite is subhedral shape and the quartz occurs as xenomorphs to subhedral crystals. Some biotite minerals were partly modified by later magmatism. The Cida granites mainly consist of K-feldspar (15–20 vol%), perthite (0–10 vol%), plagioclase (20–25 vol%), quartz (30–35 vol%), biotite (0–5 vol%), magnetite, and zircon (Figs. 3d, 3f). The plagioclase displays the well-developed polysynthetic twins and sodium-compound twins. The K-feldspar is subhedral and partly altered to kaolinite. Some K-feldspar minerals also show crossed twinning. The biotite is inlaid between the K-feldspar and quartz. 3. Analytical methods We analyzed major and trace elements analyses, zircon geochronology, and in-situ zircon Lu-Hf isotopic at the State Key Laboratory of Continental Dynamics, Northwest University, Xi’an, China (SKLCD). Whole-rock Sr-Nd isotopic data were obtained at the Guizhou Tuopu Resource and Environment Analysis Center. 3.1 Zircon U-Pb dating Zircons were separated from ~5kg samples (KY-2, CD-1, and CD-2) collected from different sampling locations within the Kuanyu and Cida granitic plutons so that sufficient and representative zircons could be selected. Zircon grains from the samples were separated using conventional heavy

liquid and magnetic techniques. Representative zircon grains were handpicked and mounted in epoxy resin disks and then polished and carbon coated. The internal morphology was examined using cathodoluminescence (CL) microscopy prior to U–Pb isotopic dating. Laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) U-Pb analyses were conducted following the method of Yuan et al. (2004) on an Agilent 7500a ICP-MS equipped with a 193-nm laser. The laser ablation spot size was approximately 32 μm.

207

Pb/206Pb,

206

Pb/238U,

237

Pb/235U and

208

Pb/232Th ratios were calculated using GLITTER 4.0 (Macquarie University),

and then corrected using the Harvard zircon 91500 as an external standard with a recommended 206Pb/238U isotopic age of 1065.4 ± 0.6 Ma (Wiedenbeck et al., 2004). The GJ-1 is also a standard sample with a recommended 206

Pb/238U isotopic age of 603.2 ± 2.4 Ma (Liu et al., 2007). Detailed analytical

techniques are described in Yuan et al. (2004). Common Pb contents were subsequently valuated using the method described in Andersen (2002). The age calculations and plotting of concordia diagrams were made using ISOPLOT (version 3.0) (Ludwig, 2003). Uncertainties are quoted at the 2 level. 3.2 Major and trace elements Weathered surfaces of the whole-rock samples were removed and fresh parts were chipped and powdered to a ~200 mesh using a tungsten carbide ball mill. Major and trace elements were analyzed by X-ray fluorescence

(XRF; Rikagu RIX 2100) and inductively coupled plasma mass spectrometry (ICP–MS; Agilent 7500a), respectively. Analyses of USGS and Chinese national rock standards (BCR-2, GSR-1, and GSR-3) showed that the analytical precision and accuracy for the major elements were generally better than 5%. For the trace element analyses, sample powders were digested using a HF+HNO3 mixture in a high-pressure Teflon bombs at 190 °C for 48 hours., The analytical error was less than 2% for most trace elements and the precision was greater than 10% (Liu et al., 2007). 3.3 Whole-rock Sr-Nd isotopes Whole-rock Sr-Nd isotopic data were obtained using a Neptune Plasma high-resolution (HR) multi-collector (MC) mass spectrometer. Sr and Nd isotopes were determined using a method similar to that of Chu et al. (2009). Sr and Nd isotopic fractionation was corrected to

87

Sr/86Sr = 0.1194 and

146

Nd/144Nd = 0.7219. During the sample runs, the La Jolla standard yielded

an average value of

143

Nd/144Nd = 0.511862 ± 5 (2σ), and the NBS987

standard yielded an average value of

87

Sr/86Sr = 0.710236 ± 16 (2σ). The

total procedural Sr and Nd blanks are b1 ng and b50 pg, respectively. NIST SRM-987 and JMC-Nd were used as certified reference standard solutions for

87

Sr/86Sr and

143

Nd/144Nd isotopic ratios, respectively. The BCR-1 and

BHVO-1 standards yielded an average of 87Sr/86Sr ratio are 0.705014 ± 3 (2σ) and 0.703477 ± 20 (2σ), respectively. The BCR-1 and BHVO-1 standards yielded an average of

146

Nd/144Nd ratio are 0.512615 ± 12 (2σ) and 0.512987

± 23 (2σ), respectively. 3.4 In-situ zircon Lu-Hf isotopic analyses The in-situ zircon Hf isotopes were analyzed using a Neptune MC-ICPMS. The laser repetition rate was 6 Hz at 100 mJ and the spot size was 30 μm. Instrument information is available in Bao et al. (2017). The detailed analytical technique is depicted by Yuan et al. (2008). During the analyses, the measured values of well-characterized zircon standards (91500, GJ-1, and Monastery) were consistent with the recommended values within 2σ (Yuan et al., 2008). The obtained Hf isotopic compositions were 0.282016 ± 20 (2σn, n = 84) for the GJ-1 standard and 0.282735 ± 24 (2σn, n = 84) for the Monastery standard, consistent to within 2σ of the recommended values (Yuan et al., 2008). The initial 176Hf/177Hf ratios and εHf(t) were calculated with reference to the chondritic reservoir (CHUR) at the time of zircon growth from the magmas. The decay constant for 176Lu of 1.867 × 10−11 year−1 (Soderlund et al., 2004), chondritic

176

Hf/177Hf ratio of 0.282785, and

176

Lu/177Hf ratio of

0.0336 were adopted. The depleted mantle model ages (TDM) used for basic rocks were calculated with reference to the present-day depleted mantle 176

Hf/177Hf ratio of 0.28325, similar to that of the average MORB (Nowell et al.,

1998) and 176Lu/177Hf = 0.0384 (Griffin et al., 2000). For the zircons from felsic rocks, we also calculated the Hf isotope “crustal” model age (TDMC) by assuming that its parental magma was derived from an average continental crust, with

176

Lu/177Hf = 0.015, that originated from the depleted mantle

source (Griffin et al., 2000). Our conclusions remain unaffected even if other decay constants were used. 4. Results 4.1 Zircon U-Pb geochronology Zircon grains from three typical peraluminous granites samples, including one sample (KY-2) from the Kuanyu pluton and two samples (CD-1, CD-2) from the Cida pluton, were collected and analyzed. The zircon U-Pb isotopic data are presented in the Table 1 and illustrated in a U-Pb concordia diagram (Fig. 4). Kuanyu granites Zircon grains from sample KY-2 in the Kuanyu granites are dominantly colorless, transparent, and euhedral prismatic crystals. The crystal length ranges from 50 to 200 μm with aspect ratios around 1:1 to 2:1. Most grains from this sample have well-developed oscillatory zoning, which indicates a magmatic origin (Hoskin and Schaltegger, 2003). The 33 concordant analyses spots are characterized by

206

Pb/238U ages ranging from 833 ± 8 to

847 ± 9 Ma with a weighted mean age of 840.0 ± 1.5 Ma (MSWD = 0.67, n = 33) (Figs. 4a, 4b), interpreted to be the crystallization age of the Kuanyu granites. Cida granites Zircons from sample CD-1 are transparent and subhedral short-prismatic crystals with aspect ratios from 1:1 to 3:2. These zircon grains range from 50

to 100 μm long and also show the well-developed oscillatory zoning, a typical indicator of an igneous origin. The zircons from sample CD-1 have a wide range of Th contents (107–1101 ppm), U contents (175–1068 ppm), and Th/U ratios (0.42–1.21). Their 28 concordant analytical spots yield

206

Pb/238U ages

varying from 830 ± 9 to 845 ± 9 Ma and produce a weighted mean age of 835.2 ± 1.6 Ma (MSWD = 0.57, n = 33) (Figs. 4c, 4d). Zircons from sample CD-2 are also subhedral stubby crystals with aspect ratios around 1:1. The crystals are furvous and range from 40 to 100 μm long. The zircon grains from the sample CD-2 contain variable U (287–2046 ppm), Th (83–2795 ppm), with Th/U ratios of 0.50–1.98. Among the 18 concordant analyses plots, these samples yield a concordant weighted mean age of 834.9 ± 1.9 Ma (MSWD = 0.35, n = 18) (Figs. 4e, 4f). 4.2 Major and trace element compositions Major and trace element data measured from the Kuanyu and Cida peraluminous granites are listed in Table 2 and Figs. 5–7. The Neoproterozoic juvenile mafic lower crust-derived granitoids are shown for comparison (Lai et al., 2015a; Zhu et al., 2019a). All samples in the A/NK versus A/CNK diagram (Fig. 5a) plot in the peraluminous granites field, and mostly in the alkali-calcic field on the (Na2O + K2O - CaO) versus SiO2 diagram (Fig. 5b), The kuanyu and Cida peraluminous granites are both a potassium-rich series with high K2O/Na2O ratios (1.44–3.25) (Fig. 5c). They also show the similar Mg# (molar (MgO/(MgO + FeOT)) × 100)) values (17–33) to those pure crustal melts

under continental crust pressure and temperature (P-T) conditions (Fig. 5d). Kuanyu granites The Kuanyu granites show a range of major elements compositions, particularly with regards to SiO2 contents (66.9–75.0 wt.%), total alkali contents (K2O + Na2O = 7.43–9.53 wt.%), K2O/Na2O ratios (1.44–3.25), and Al2O3 contents (12.3–15.8 wt.%), with A/CNK values of 1.05–1.18. FeOT, CaO, Al2O3, MgO, and TiO2 all decrease with increasing SiO2 contents (Fig. 6). The samples also contain moderate P2O5 (0.06–0.22 wt.%) and Mg# values (17–33). On the chondrite-normalized REE pattern diagram (Fig. 7a), the Kuanyu granites display similar rare earth elements (REEs) distribution patterns, enrichment in light rare earth elements (LREEs) with (La/Yb)N = 8.7–19.6, relatively flat heavy rare earth elements (HREEs) patterns with (Dy/Yb)N = 1.22–1.80. They have high total REE contents of 231–336 ppm and clearly display negative Eu anomalies (Eu/Eu* = 0.23–0.57). On the primitive-mantle normalized diagram (Fig. 7b), the Kuanyu granites exhibit the enrichment of large ion lithophile elements (LILEs) (e.g., Rb, Th, U, and K) and Pb, and depletion of high field strength elements (HFSEs) (e.g., Nb, Ta, Zr, and Ti), resembling trends of the middle-upper crust (Rudnick and Gao, 2003). According to the whole-rock zircon saturation thermometry from Watson and Harrison (1983), the Kuanyu granites yield high crystallization temperature varying from 795 to 851 ºC with an average of 819 ºC. Cida granites

All the Cida granites samples show high and concentrated SiO2 contents ranging from 73.1 to 75.6 wt.%, K2O contents from 5.20 to 6.00 wt.%, Na2O contents from 2.88 to 3.29 wt.%, K2O/Na2O ratios from 1.71 to 1.96, and A/CNK values from 1.04 to 1.14. They contain relatively low CaO (0.25–0.57 wt.%), Al2O3 (12.4–13.8 wt.%), MgO (0.17–0.25 wt.%), P2O5 (0.02–0.04 wt.%), and TiO2 (0.14–0.24 wt.%) (Fig. 6). They also have low Fe2O3T (1.54–2.22 wt.%) and Mg# values (18–20). In the chondrite-normalized REE pattern diagram (Fig. 7a), the Cida granites display more fractionated REE patterns with (La/Yb)N ratios of 19.3–39.5, (Dy/Yb)N ratios of 1.64–2.27, and pronouncedly negative Eu anomalies (Eu/Eu* = 0.22–0.32). On the primitive-mantle normalized diagram (Fig. 7b), the enrichment of Rb, Th, U, K, and Pb and the depletion of Nb, Ta, Sr, and Ti are also observed. All the Cida granites have high zircon saturation temperature ranging from 790 to 845 ºC with an average of 820 ºC. 4.3 Whole-rock Sr-Nd isotopic compositions The whole-rock Sr-Nd isotopic data for the Kuanyu and Cida peraluminous granites are listed in Table 3, and a diagram of εNd(t) versus initial ratios (Isr) is shown in Fig. 8. The εNd(t) and initial

87

Sr/86Sr

87

Sr/86Sr ratios of all

samples were calculated according to concordant crystallization ages and using the model of Depaolo (1981). The Kuanyu granites have variable initial

87

Sr/86Sr ratios (Isr) from 0.7099

to 0.7217. They are characterized by enriched Nd isotopic compositions with

εNd(t) values of –5.1 to –4.9. They yield the ancient two-stage Nd model ages ranging from 1.74 to 1.75 Ga. The Cida granites yield relatively constant initial 87Sr/86Sr ratios (Isr) varying from 0.7128 to 0.7148. They also show the negative εNd(t) values of –3.5 to –2.9 and old two-stage Nd model ages of 1.60 to 1.64 Ga. 4.4 Zircon Lu-Hf isotopic compositions Zircon grains from there peraluminous granites samples (KY-2, CD-1, and CD-2) were also analyzed for in-situ Lu-Hf isotopes on the same domains with U-Pb dating. The results are shown in Table 4 and Figs. 9–10. The initial 176

Hf/177Hf, εHf(t), and two-stage model ages were calculated according to

their corresponding zircon crystallization ages. Zircons from sample KY-2 show initial 176Hf/177Hf ratios (176Hf/177Hf)i ranging from 0.282047 to 0.282302. They yield variable εHf(t) values of −7.75 to +1.31 and two-stage Hf model ages of 1643 to 2210 Ma (a mean of 1831 Ma) (Figs. 9, 10a, 10b). Zircon grains from sample CD-1 share high initial

176

Hf/177Hf ratios

(176Hf/177Hf)i from 0.282196 to 0.282384. The εHf(t) values are distributed from −3.71 to +3.21 with corresponding two-stage Hf model ages of 1519 to 1953 Ma (a mean of 1735 Ma) (Figs. 9, 10c, 10d). The zircons from sample CD-2 exhibit initial

176

Hf/177Hf ratios (176Hf/177Hf)i

varying from 0.282221 to 0.282360. Their εHf(t) values and two-stage Hf model ages are in the range of −2.15 to +3.31 and 1512 to 1854 Ma,

respectively (Figs. 9, 10e, 10f). 5 Discussion 5.1 Petrogenesis of the Neoproterozoic peraluminous granites 5.1.1 Magma source The Kuanyu and Cida granites formed at ca. 840–835 Ma. The samples are all geochemically characterized by the peraluminous to strongly peraluminous features with high A/CNK values ranging from 1.04 to 1.18. They display a geochemical consistent with experimental melts under crustal conditions (Figs. 6, 7) (Guo et al., 2012). Experimental petrology has revealed that peraluminous intermediate to felsic melts can form by the partial melting of metaluminous basaltic to andesitic rocks under crustal conditions (Chappell, 1999; Chappell et al., 2012; Rapp and Watson, 1995; Sission et al., 2005; Sylvester, 1998). Nevertheless, such peraluminous rocks usually contain low K2O contents with K2O/Na2O ratios <1, which significantly contrasts with the results presented here of peraluminous granites

with

particularly high K2O contents (4.61–7.29 wt.%) and K2O/Na2O ratios (1.44–3.25 > 1) (Fig. 5c). We can therefore preclude metabasaltic rocks in the magma source. Previous voluminous studies also suggested that the peraluminous, silica-rich rocks are mainly generated by the partial melting of metasedimentary protoliths in a mature continental crust source including the clay-rich metapelites and clay-poor metagreywackes (psammites) (Clemens, 2003; Sylvester, 1998). Several lines of evidence suggest that the Kuanyu

and

Cida

peraluminous

granites

predominantly

originate

from

a

metasedimentary source under middle-upper crust conditions. (1) The Kuanyu and Cida peraluminous granites contain high and variable concentrations of SiO2 (66.9–75.6 wt.%), K2O (4.61–7.29 wt.%), and A/CNK ratios (1.04–1.18), suggesting that their sources are dominated by metasedimentary rocks rather than meta-igneous protoliths (Cai et al., 2011; Zhu et al., 2018). (2) The weakly fractionated HREE patterns, low (Gd/Yb)N values (1.85–4.66)

and

Sr/Y

ratios

(1.31–7.62)

indicate

that

these

peraluminous granites were derived from a relatively shallow crustal source above the garnet stability depth (Patiňo Douce, 1996; Rossi et al., 2002). In addition, the samples display the pronounced Th, U, K, and Pb peaks and Nb, Ta, Ti, Ba, Sr, and Eu troughs (Fig. 7), which resemble geochemical characteristics of middle-upper crust-derived melts (Chen et al., 2014; Rudnick and Gao, 2003). (3) On the diagrams of CaO/Al2O3 versus CaO + Al2O3 and Al2O3/(Fe2O3T + MgO +TiO2) versus Al2O3 + Fe2O3T + MgO +TiO2 (Patiňo Douce, 1999) (Figs. 11a, 11b), the compositions of the peraluminous granites are comparable with experimental melts of various metasediments under relatively low pressure (<5 kbar), suggesting a shallow crustal level (Cai et al., 2011). This is in agreement with CIPW-normative Qz-Ab-Or phase compositions (Fig. 11c), which also reflect precursor

magmas that were derived from the relatively low pressure conditions (1–5 kbar) in a shallow crustal source. They also display relatively higher whole-rock Zr saturation temperatures than juvenile mafic lower crust-derived granitoids (Fig. 11d) (Lai et al., 2015a; Zhu et al., 2019a). (4) The enriched Sr-Nd isotopic compositions (e.g., (87Sr/86Sr)i = 0.7099 to 0.7217, εNd(t) = −5.1 to −2.9) together with ancient two-stage Nd model ages (1.60 Ga to 1.75 Ga) suggest an evolved and ancient crustal source of these peraluminous granites (Zhu et al., 2018), distinct from the Sr-Nd isotopic features of previously reported Neoproterozoic mantle-derived mafic-intermediate rocks and juvenile mafic lower crust-derived granitoids in the western Yangtze Block (Fig. 8). Sylvester. (1998) proposed that peraluminous granites can inherit different CaO/Na2O

ratios

by

the

partial

melting

of

various

protoliths.

Metapelite-derived melts usually contain lower CaO/Na2O ratios (< 0.3) than the metagreywacke-derived counterparts (CaO/Na2O > 0.3) (Sylvester, 1998). On the CaO/Na2O versus Al2O3/TiO2 diagram (Fig. 12a), the majority of the Kuanyu peraluminous granite samples display high and variable CaO/Na2O ratios (0.22–0.65, mostly >0.3) and low Al2O3/TiO2 ratios (25.3–65.8), suggesting a dominant origin of psammites (metagreywackes). All of the Cida peraluminous granite samples yield low CaO/Na2O ratios (0.09–0.19 < 0.3) and moderate Al2O3/TiO2 ratios (51.2–88.4), indicating a metapelite source (Fig. 12a). In term of the Rb/Ba versus Rb/Sr diagram (Fig. 12b), the Kuanyu

and Cida peraluminous granites suggest an affinity to a heterogeneous source of metapelite- and metagreywacke-derived melts, as indicated by moderate Rb/Ba (1.68–3.86) and Rb/Sr (0.32–0.85) ratios. Furthermore, differing from juvenile mafic lower crust-derived granitoids along the western periphery of the Yangtze Block (Lai et al., 2015a; Zhu et al., 2019a), the peraluminous granites in this study contain high molar Al2O3/(MgO + FeOT) values of 2.04 to 5.23 and low molar CaO/(MgO + FeOT) values of 0.15–0.48 (Fig. 12c) (Altherr et al., 2000), which are scattered in the metapelites and metagreywackes

fields.

These

geochemical

features

all

support

a

heterogeneous metasedimentary source for the peraluminous granites studied here. Previous studies have interpreted the wide range of isotopic variation in peraluminous granites to reflect isotopic heterogeneity inherited from a heterogenous source (Champion and Bultitude, 2013; Huang et al., 2019; Villaros et al., 2012; Wang et al., 2018; Zhu et al., 2018). Source heterogeneity can be transferred to a granitic magma by the formation of discrete magma batches (Villaros et al., 2012). The Kuanyu and Cida peraluminous granites in this study contain a wide range of zircon εHf(t) values varying from −7.75 to +1.31 and −3.71 to +3.31, respectively (Figs. 9, 10), further demonstrating the heterogeneous metasedimentary source (metapelites + metagreywackes) (Zhu et al., 2018). In addition, the ancient two-stage Hf model ages of 1643 to 2210 Ma for the Kuanyu granites and 1512 to 1953 Ma for the Cida granites can also support a evolved continental

crustal source (Fig. 10) (Zhu et al., 2018). In summary, our results suggest that the Kuanyu and Cida peraluminous granites in the western Yangtze Block predominantly formed by the partial melting of heterogeneous metasedimentary protoliths, including variable proportions of metagreywackes and metapelites from an evolved continental crust source (i.e., middle-upper crust level). 5.1.2 Hybridization process or disequilibrium melting? As mentioned above, the peraluminous granites investigated in this study were derived from heterogeneous metasedimentary sources (metapelites + metagreywackes). It is notable that these peraluminous granites partly display a depleted Hf isotopic compositions (εHf(t) values up to +3.31) (Figs. 9, 10). This phenomenon is likely caused by the hybridization process between mantle- and crust-derived inputs (Brown, 2013; Chen et al., 2014; Clemens, 2003; Kemp et al., 2007) or disequilibrium partial melting of zircon-bearing crustal rocks (Dou et al., 2019; Farinia et al., 2014; Flowerdew et al., 2006; IIes et al., 2018; Kong et al., 2019; Tang et al., 2014; Wang et al., 2018). There is a general knowledge that mantle-derived magmas may provide necessary heat and materials for crustal melting, and peraluminous granites can crystallize from both mantle- and crust-derived inputs (Brown, 2013; Clemens, 2003; Jiang et al., 2017; Sylvester, 1998). The Kuanyu and Cida peraluminous granites in this study yield positive and negative zircon εHf(t)

values ranging from −7.75 to +3.31 (Figs. 9, 10), suggesting an open system and mixing source (Kemp et al., 2007). Their heterogeneous zircon εHf(t) values differ from the zircon Hf isotopic compositions of Neoproterozoic juvenile mafic lower crust-derived granitoids in the western Yangtze Block, but are partly consistent with Neoproterozoic peraluminous granites from the Jiangnan fold belt (Jiang et al., 2017; Wang et al., 2013, 2014; Zhao et al., 2013), further indicating the possibility of magma mixing between the mantleand crust-derived components (Belousova et al., 2006). However, the following hints lend limited support to the hybridization process between crustal melts and mantle-derived magmas. First, the significant microgranular mafic enclaves and disequilibrium mineral pairs, which are strong evidences for magma mixing (Tang et al., 2014; Vernon, 1984), are rarely observed in the field and micrographs (Fig. 3). Second, magma mixing of voluminous mantle- and crust-derived melts elevates the Mg# values of the resultant melts (Jiang et al., 2017), but the high observed SiO2 (66.9–75.6 wt.%) contents and low Mg# values (17–33) measured here are similar to pure crustal partial melts (Fig. 5d), which weakens the hybridization process. There is no clear positive correlation between La/Sm and Th/Sc ratios for our granites samples (Fig. 13a), further ruling out the possibility of magma mixing (Huang et al., 2019). Third, Dickin. (2018) suggested that a positive correlation between 1/Sr and initial

87

Sr/86Sr values is expected for magma

mixing between mafic and felsic magmas. However, the negative correlation

of our peraluminous granites argues against the hybridization process (Fig. 13b). In addition, a negative correlation of SiO2 and εNd(t) values would develop during mixing (Jiang et al., 2017), which is not observed in the samples studied here (Fig. 13c). In summary, the comprehensive evidence leads us to support that the hybridization of crustal melts with mantle-derived magmas played a minor role in the genesis of the peraluminous granites. Underplating of mantle-derived magma merely acted as a heat source that triggered the partial melting of a middle-upper curst source. Alternatively, the zircon Hf isotopic heterogeneity in our peraluminous granites may result from disequilibrium partial melting (IIes et al., 2018; Kong et al., 2019; Tang et al., 2014; Wang et al., 2018). As the major carrier of Hf, zircon controls the Hf budget at the source, and its dissolution may dictate Hf isotopic evolution in the melt (Tang et al., 2014). Flowerdew et al. (2006) proposed that the varying zircon dissolution rate can lead to heterogeneous zircon εHf(t) values between different melt batches at a single source and give rise to a decoupling of the Hf isotope system from other radiogenic isotope systems. In this study, the existence of zircons xenocrysts in our peraluminous granites suggests that some residual zircons from the source were entrained by the melt during melt loss (Fig. 4) (Kong et al., 2019). These residual zircons would retain the Hf relative to Nd, which leads to relatively high Nd/Hf (6.17–9.76) ratios and low Hf (5.00–8.43 ppm) concentrations in our peraluminous granites. Accordingly, the undissolved residual zircons may

retain a significant amount of

177

Hf at the source, elevating the

ratios of the melts and decoupling them from the

177

Hf/176Hf

143

Nd/144Nd ratios (Kong et

al., 2019; Tang et al., 2014). Nd-Hf isotopic decoupling was observed in our peraluminous granites, which show that enriched Nd isotopes (εNd(t) = −5.1 to −2.9) and heterogeneous Hf isotopes (εHf(t) = -7.75 to +3.31). Zirconium is abundant in the continental crust with average concentrations ranging from 68 ppm in the lower crust to 193 ppm in the upper curst (Rudnick and Gao, 2003). This means that the zircon effect may be common during the crustal melting because of the slow disequilibrium melting of zircon, (Tang et al., 2014). Because high Zr concentrations at the source can easily saturate the melt with zircon and zircon dissolution will cease until more melt is generated to dilute the remaining Zr at the source, the Zr concentration at the source is a significant factor for controlling the zircon dissolution rate (Kong et al., 2019; Tang et al., 2014). As mentioned in section 5.1.1, our peraluminous granites were derived from a middle-upper crustal source. The presence of residual zircon grains and high Zr concentrations (159–304 ppm) in our peraluminous granites indicate the high initial Zr concentrations. The model presented by Tang et al. (2014) showed that when the initial Zr concentration at the source is sufficiently high (e.g., >100 ppm), the inter-batch Hf varies from low concentration and highly radiogenic to high concentration and less radiogenic than the bulk protolith, which may produce a melt extracted from a single source that evolves from a mantle-like source at the early stage to a crust-like

source after extensive melting. They emphasized that the mixing of magma batches from individual crustal sources may mimic the Hf isotopic features from the hybridization of crust- and mantle-derived magmas (Tang et al., 2014), which is similar to that observed in our peraluminous granites with positive and negative zircon εHf(t) values (–7.75 to +3.31). The high Zr content in the source along with disequilibrium melting can therefore explain the isotopic heterogeneity in our peraluminous granites. In addition, variable Sr isotopic compositions may also reflect significant disequilibrium melting process during crustal anatexis (Farina et al., 2014; Mcleod et al., 2012; Zeng et al., 2005a, 2005b), which can be displayed in our peraluminous granites with variable (87Sr/86Sr)i values from 0.7099 to 0.7217 (Fig. 8). Therefore, the integrated evidences leads to the conclusion that the zircon Hf isotopic heterogeneity in our peraluminous granites may be attributed to disequilibrium partial melting of a heterogeneous metasedimentary source, similar to that of peraluminous granites from the Altai area and Jiangnan orogen (Kong et al., 2019; Tang et al., 2014). Multi-sourced magma mixing between crust- and mantle-derived components is therefore insignificant for our peraluminous granites in the western margin of the Yangtze Block. 5.2 Petrological and geological implications 5.2.1 Formation of Neoproterozoic peraluminous granites There are several main mechanisms that account for the generation of peraluminous granites, such as crustal reworking during ridge subduction,

crustal thickening and melting during continental collision, post-collisional collapse and melting of pre-existed sediments in the back-arc basin, or continental crust reworking in the early stage of subduction (Barbarin, 1999; Cai et al., 2011; Chen et al., 2014; Collision, 2002; Collins and Richard, 2008; Liu and Zhao, 2018; Sylvester, 1998). Ridge subduction can trigger the partial melting of continental crust and generate peraluminous granites (Cai et al., 2011) but it will cause the high-T and low-P metamorphism (Jiang et al., 2010), which remain unreported from Neoproterozoic rocks of the western Yangtze Block. We can thus preclude the ridge subduction model. The zircon U-Pb ages (ca. 840–835 Ma) of the Kuanyu and Cida peraluminous granites are obviously older than the formation age of thickened crust-derived adakites (ca. 800–780 Ma) along the margins of Yangtze Block (Huang et al., 2009; Zhao et al., 2010; Zhu et al., 2019b). There is also no geological evidence for the presence of an early Neoproterozoic back-arc basin around the Miyi region. Therefore,

the

continental

collisional-related

models

are

therefore

unreasonable, and continental crust reworking in the early stage of subduction setting might account for the genesis of the Kuanyu and Cida peraluminous granites in the western Yangtze Block. Chen et al. (2014) suggested that the Cambrian Chaidanuo peraluminous granites in the North Qilian suture zone were formed by the re-melting of crustal materials during the early onset of subduction initiation. Similarly, a subduction setting is also proposed in the western margin of the Yangtze Block during the dominant

interval of ca. 860 Ma to 750 Ma (Lai et al., 2015a, 2015b; Sun et al., 2007, 2008; Zhou et al. 2002, 2006a, 2006b; Zhao et al., 2008a, 2008b, 2017, 2018; Zhu et al., 2017, 2019a, 2019b). Although a mantle plume setting is a controversial model for the widespread Neoproterozoic magmatism in the western Yangtze Block (Li et al., 2003, 2006, 2008), an increasing number of sedimentary, geophysical, and igneous studies of the region strengthen the viewpoint of subduction process (Gao et al., 2016; Sun et al., 2008, 2009; Zhao et al., 2017, 2018). Sun et al. (2009) concretely proposed that detrital zircons in Precambrian strata show a vital period of juvenile magmatism at ca. 1000–740 Ma, which is consistent with the interval of long-lasting Neoproterozoic subduction along the western Yangtze Block. Gao et al. (2016) proposed that the multichannel seismic reflection profiles across the Sichuan Basin are similar to the geometry of ancient subduction-related mantle, which has been explained as the remnant mantle of Neoproterozoic subduction process in the Yangtze Block. Zhao et al. (2017) suggested that the western margin of the Yangtze Block is an Andean-type arc system by the evidence of the ca. 800 Ma SSZ-type Shimian ophiolite assemblage. They further summarized that Neoproterozoic magmatism in the western and northern margins of the Yangtze Block was controlled by continuous slab subduction and subduction-transform-edge-propagator system (Zhao et al., 2018 and references therein). We therefore support that the massive Neoproterozoic magmatism in the western Yangtze Block, including the Kuanyu and Cida

peraluminous granites in this study, were formed under persistent subduction process. As mentioned above, the crystallization ages of our studied peraluminous granites (ca. 840-835 Ma) approach the age of the Guandaoshan pluton (ca. 860 Ma) that is considered to be the products of initial subduction process in the western Yangtze Block (Du et al., 2014). The age constraint implies that these peraluminous granites were generated in the early stage of subduction. Combining with the regional tectonic background, we suggest that the Kuanyu and Cida peraluminous granites may have formed by the following process (Fig. 14a). During the early subduction of an oceanic slab beneath the western margin of the Yangtze Block, strong slab rollback towards the vertical direction increased the subduction rate (Niu et al., 2003) and lead to intensive seafloor spreading (Gerya, 2011; Zhu et al., 2009). Trench retreat and extension of the overriding plate would subsequently be expected in the fore-arc region (Chen et al., 2014). The overriding plate would be rheologically weakened by arc magmatism, therefore resulting in a regionally thinning of the overriding plate (Gerya and Meilick, 2011). This process will also lead to decompression melting of the asthenosphere mantle (Gerya et al., 2008) and simultaneously generation of basaltic magmatism along the western Yangtze Block, i.e., the parental magma of the ca. 860 Ma Guandaoshan pluton, the ca. 842 Ma Xiacun mafic intrusions, and the ca. 840 Ma MORB-type Yanbian basalt (Du et al., 2014; Guo et al., 2009; Sun et

al., 2007). In the meantime, the overlaying continental crust in the Miyi region may have been heated by the strong upwelling of voluminous mantle-derived magma and undergone disequilibrium partial melting of heterogeneous metasediments when the temperature reached the solidus (Chen et al., 2014), producing the Kuanyu and Cida peraluminous granites in the Miyi region. In summary, the Kuanyu and Cida peraluminous granites represent partial melting of mature continental crust under early subduction stages during the Neoproterozoic. 5.2.2 Widespread Neoproterozoic juvenile and mature crustal melting The enriched Sr-Nd isotopes and negative-dominantly zircon εHf(t) values, together with the whole-rock geochemical evidences, suggest that the Kuanyu and Cida peraluminous granites in the western Yangtze Block represent mature continental crust-derived metasediment melts. Actually, Neoproterozoic large-scale crustal growth and melting occurred along the western periphery of the Yangtze Block in a subduction setting (Huang et al., 2009; Zhao et al., 2008a; Zhu et al., 2019a, 2019b). Zhao et al. (2008a) proposed that the voluminous mafic-intermediate plutons, which display depleted zircon Hf isotopic compositions (Fig. 14b), were derived from a depleted mantle source modified by subduction components. The extraction of voluminous mantle melts was a significant process involved in crustal growth. They also suggested that several adakitic granitoid plutons formed by the partial melting of a subduction oceanic slab, and the recycling of oceanic

crust was also a main contributor for crustal growth (Zhao et al., 2008a). Moreover, there was widespread juvenile and ancient crustal melting along the western Yangtze Block during the Neoproterozoic (Zhu et al., 2019a) (Fig. 14b). In the Kangding-Shimian region (Fig. 2a), the ca. 850 Ma Tianquan peraluminous granites were thought to generate from the partial melting of crust-derived basalts and greywackes under H2O saturation and a high geothermal gradient (Lai et al., 2015b). The ca. 816 Ma Daxiangling A-type granites have been considered from recycled juvenile crust-derived rocks, and the ca. 800 Ma Shimian I-type granites were derived from an ancient TTG source as a result of underplating of mantle-derived mafic magmas (Zhao et al., 2008b). In addition, the ca. 777 Ma Shimian K-feldspar granites formed by the re-melting of middle-upper crust-derivation metagreywackes (Zhu et al., 2017), and the ca. 770 Ma Baoxing granites have been explained by the partial melting of the juvenile crust according to the positive zircon εHf(t) values of +2.53 to +10.58 (Fig, 14b) (Meng et al., 2015). Moreover, Lai et al. (2015a) proposed that relatively younger ca. 754 Ma Luding high-Mg# quartz monzodiorites were generated by ~40% partial melting of newly formed mafic lower crust. They also suggested that the ca. 748 Ma Kangding granodiorite was produced by the partial melting of a plagioclase-rich crustal source (Lai et al., 2015a). In the Mianning region (Fig. 2a), the ca. 780 Ma Mianning highly fractionated A2-type granites were ascribed from a juvenile crust source

owing to the depleted whole-rock Nd isotopes (εNd(t) = +2.97 to +5.24) and zircon Hf isotopes compositions (εHf(t) = +9.2 to +12.1) (Fig. 14b) (Huang et al., 2008). In the Miyi region, our identification is that the ca. 840–835 Ma Kuanyu and Cida peraluminous granites were mainly formed by the reworking of heterogeneous metasediments in the evolved middle-upper crust source. Additionally, Guo et al. (2009) proposed that the ca. 803 Ma Xiacun granite and ca. 790 Ma Yonglang granite were derived from the ancient crust-derived materials. In the Panzhihua-Yanbian region (Fig. 2a), the recently identified ca.

780

Ma

Dalu

I-type

granodiorites-granites

association

yielded

positive-dominantly zircon εHf(t) values (–4.65 to +7.39) (Fig. 14b), and were considered to be from the juvenile mafic lower crust-derived melts and mixing of juvenile curst-derived melts and mature metasediments melts (Zhu et al., 2019a). These ca. 850–740 Ma granitoids magmatism correspond with an interval of a Neoproterozoic subduction setting. In general, the western Yangtze Block underwent long-lasting crustal re-melting during the Neoproterozoic subduction process, including not only the juvenile mafic lower crust but also mature continental crustal compositions. 6 Conclusions (1) Zircon U-Pb ages show that the Kuanyu and Cida peraluminous granites were formed at ca. 840–835 Ma, coeval with the early Neoproterozoic magmatism in the western margin of the Yangtze Block. (2) The Kuanyu and Cida peraluminous granites were mainly produced by

the partial melting of mature and heterogeneous metasediments in the middle-upper crust source. The absence of sufficient evidence for magma mixing between mantle-derived magmas and crust-derived melts, the heterogeneous zircon Hf (εHf(t) = -7.75 to +3.31) isotopic compositions can be ascribed to disequilibrium partial melting. (3) Compared with the mantle-derived mafic-intermediate magmatism and juvenile mafic lower crust-derived granitoid magmatism in the western Yangtze Block, we suggest that the Kuanyu and Cida peraluminous granites represent melting of mature continental crust during the early stage of Neoproterozoic subduction. Widespread Neoproterozoic crustal melting, including juvenile mafic lower crust and mature crustal sources, occurred along the western margin of the Yangtze Block. Acknowledgement Thanks so much for the help and constructive comments from Chief editor Prof. Guochun Zhao and other anonymous reviewers, which significantly improved the shape, language, and discussion of this manuscript. We also grateful to the further English polish from Esther Posner, PhD. This work was jointly supported by the National Natural Science Foundation of China [Grant Nos. 41421002, 41802054 and 41772052] and the program for Changjiang Scholars and Innovative Research Team in University [Grant IRT1281]. Support was also provided by the Foundation for the Author of National Excellent Doctoral Dissertation of China (201324) and independent

innovation project of graduate students of Northwest University [YZZ17192]. References Altherr, R., Holl, A., Hegner, E., Langer, C., Kreuzer, H., 2000. High-potassium, calc-alkaline I-type plutonismin the European Variscides: northern Vosges (France) and northern Schwarzwald (Germany). Lithos 50, 51–73. Andersen, T., 2002. Correction of common lead in U–Pb analyses that do not report 204Pb. Chemical Geology, 192(1–2), 59–79. Bao, Z.A., Chen, L., Zong, C.L., Yuan, H.L., Chen, K.Y., Dai, M.N., 2017. Development of pressed sulfide powder tablets for in situ, sulfur and lead isotope measurement using LA-MC-ICP-MS. International Journal of Mass Spectrometry, 421, 255–262. Barbarin B., 1999. A review of the relationships between granitoid types, their origins and their geodynamic environments. Lithos, 46(3), 605–626. Belousova, E.A., Griffin, W.L., O’Reilly, S.Y., 2006. Zircon crystal morphology, trace element signatures and Hf isotope composition as a tool for petrogenetic modelling: Examples from eastern Australian granitoids. Journal of Petrology, 47, 329–353. Brown. M., 2013, Granites: from genesis to emplacement. Geological Society of America Bulletin, 125, 1079–1113. Cai, K.D., Sun, M., Yuan, C., Zhao, G.C., Xiao, W.J., Long, X.P., Wu, F.Y., 2011.

Geochronology,

petrogenesis

and

tectonic

significance

of

peraluminous granites from the Chinese Altai, NW China. Lithos, 127(1-2), 261-281. Champion, D.C., Bultitude, R.J., 2013. The geochemical and Sr, Nd isotopic characteristics of Paleozoic fractionated S-types granites of north Queensland: implications for S-type granite petrogenesis. Lithos, 162–163(2), 37–56. Chappell, B.W., White, A. J.R., 1992. I- and S-type granites in the Lachlan

fold belt. Transactions of the Royal Society of Edinburgh: Earth Sciences, 83 Chappell, B.W., 1999. Aluminium saturation in I- and S-type granites and the characterization of fractionated haplogranites. Lithos, 46(3), 535–551. Chappell, B.W., White, A. J.R., 2001. Two contrasting granite types: 25 years later. Australian Journal of Earth Sciences, 48(4), 489–499. Chappell B.W., Bryant C.J., Wyborn D., 2012. Peraluminous I-type granites. Lithos, 153(8), 142–153. Chen, Y.X., Song, S.G., Niu, Y.L., Wei, C.J., 2014. Melting of continental crust during subduction initiation: A case study from the Chaidanuo peraluminous granite in the north Qilian suture zone. Geochimica et Cosmochimica Acta, 132, 311–336. Chu, Z.Y., Chen, F.K., Yang, Y.H., Guo, J.H., 2009, Precise determination of Sm, Nd concentrations and Nd isotopic compositions at the nanogram level in geological samples by thermal ionization mass spectrometry: Journal of Analytical Atomic Spectrometry, 24, 1534–1544. Clemens, J.D., 2003. S-type granitic magmas-petrogenetic issues, models and evidence. Earth Science Review, 61, 1–18. Clemens, J.D., and Stevens, G., 2012. What controls chemical variation in granitic magmas? Lithos, 134–135, 317–329. Clemens, J.D., Regmi, K., Nicholls, I.A., Weinberg, R., Maas, R., 2016. The Tynong pluton, its mafic synplutonic sheets and igneous microgranular enclaves: the nature of the mantle connection in I-type granitic magmas. Contributions to Mineralogy and Petrology, 171(4), 35. Clemens J.D., 2018. Granitic magmas with I-type affinities, from mainly metasedimentary sources: The Harcourt batholith of southeastern Australia. Contributions to Mineralogy and Petrology, 173(11), 93. Collins,

W.J.,

1996.

Lachlan

Fold

Belt

granitoids:

products

of

three-component mixing. Trans. Roy. Soc. Edinb.: Earth Sci. 87, 171–181.

Collins W.J., 1998. Evaluation of petrogenetic models for Lachlan Fold Belt granitoids: implications for crustal architecture and tectonic models. Australia Journal of Earth Science, 45, 483–500. Collins W.J., 2002. Hot orogens, tectonic switching, and creation of continental crust. Geology, 30, 535–538. Collins W.J., Richards S.W., 2008. Geodynamic significance of S-type granites in circum-Pacific orogens. Geology, 36, 559–562. DePaolo, D.J., 1981. A Neodymium and Strontium Isotopic Study of the Mesozoic Calc-Alkaline Granitic Batholiths of the Sierra Nevada and Peninsular Ranges, California. Granites and Rhyolites. Journal of Geophysical Research, 86(B11), 10470–10488. Dickin, A.P., 2018. Radiogenic Isotope Geology, Third Edition. Cambridge University Press, Cambridge, 171–172. Dou, J.Z., Sibel, W., He, J.F., Chen, F.K., 2019. Different melting conditions and petrogenesis of peraluminous granites in western Qinling, China, and tectonic implications. Lithos, 2019, 336–337, 97–111. Du, L.L., Guo, J.H., Nutman, A.P., Wyman, D., Geng, Y.S., Yang, C.H., Liu, F.L.,

Ren,

L.D.,

Zhou,

X.W.,

2014.

Implications

for

Rodinia

reconstructions for the initiation of Neoproterozoic subduction at ~860 Ma on the western margin of the Yangtze Block: evidence from the Guandaoshan Pluton. Lithos, s196–197, 67–82. Farina, F., Dini, A., Rocchi, S., Stevens, G., 2014. Extreme mineral-scale sr isotope heterogeneity in granites by disequilibrium melting of the crust. Earth and Planetary Science Letters, 399, 103–115. Flowerdew, M.J., Millar, I.L., Vaughan, A.P.M., Horstwood, M.S.A., Fanning, C.M., 2006. The source of granitic gneisses and migmatites in the Antarctic Peninsula: A combined U-Pb SHRIMP and laser ablation Hf isotope study of complex zircons: Contributions to Mineralogy and Petrology, 151, 751–768. Frost, B.R., Barnes, C.G., Collins, W.J., Arculus, R.J., Ellis, D.J., Frost, C.D.,

2001. A geochemical classification for granitic rocks. Journal of Petrology, 42, 2033–2048. Gan, B.P., Lai, S.C., Qin, J.F., Zhu, R.Z., Zhao, S.W., Li, T., 2017. Neoproterozoic alkaline intrusive complex in the northwestern Yangtze Block, Micang Mountains region, south china: petrogenesis and tectonic significance: International Geology Review, 59(3), 311–332. Gao, R., Chen, C., Wang, H.Y., Lu, Z.W., Brown, L., Dong, S.W., Feng, S.Y., Li, Q.S., Li, W.H., Wen, Z.P., Li, F., 2016. SINOPROBE deep reflection profile reveals a Neo-proterozoic subduction zone beneath Sichuan basin. Earth and Planetary Science Letters, 454, 86–91. Gao, S., Ling, W.L., Qiu, Y., Zhou, L., Hartmann, G., Simon, K., 1999. Contrasting geochemical and Sm–Nd isotopic compositions of Archean metasediments from the Kongling high–grade terrain of the Yangtze craton: Evidence for cratonic evolution and redistribution of REE during crustal anatexis: Geochimica Et Cosmochimica Acta, 63(13–14), 2071–2088. Geng, Y.S., Yang, C.H., Wang, X.S., Du, L.L., Ren, L.D., Zhou, X.W., 2008. Metamorphic basement evolution in western margin of Yangtze Block: Geological Publishing House, Beijing 1–215 (in Chinese). Gerya T.V., 2011. Future directions in subduction modeling. Journal of Geodynamic, 52, 344–378. Gerya T.V., Meilick F.I., 2011. Geodynamic regimes of subduction under an active margin: effects of rheological weakening by fluids and melts. Journal of Metamorphic Geology, 29, 7–31. Gerya T.V., Connolly J.A.D., Yuen D.A., 2008. Why is terrestrial subduction one-sided? Geology, 36, 43–46. Griffin, W.L., Pearson, N.J., Belousova, E., Jackson, S.E., van Achterbergh, E., O'Reilly, S.Y., Shee, S.R., 2000. The Hf isotope composition of cratonic mantle: LAM–MC-ICPMS analysis of zircon megacrysts in kimberlites. Geochimica et Cosmochimica Acta, 64(1), 133–147.

Guo, C.L., Wang, D.H., Chen, Y.C., Zhao, Z.G., Wang Y.B., Fu X.F., Fu, D.M., 2007. SHRIMP U-Pb zircon ages and major element, trace element and Nd-Sr isotope geochemical studies of a Neoproterozoic granitic complex in western Sichuan: petrogenesis and tectonic significance: Acta Petrologica Sinica, 23(10), 2457–2470 (in Chinese with English abstract). Guo, F., Fan, W.M., Li, C.W., Zhao, L., Li, H.X., Yang, J.H., 2012. Multi-stage crust-mantle

interaction

in

SE

China:

temporal,

thermal

and

compositional constraints from the Mesozoic felsic volcanic rocks in eastern Guangdong-Fujian provinces, Lithos, 150, 62–84. Hacker., B.R., Wallis., S.R., Ratschbacher, L., Grove, M., Gehrels, G., 2006. High-temperature geochronology constraints on the tectonic history and architecture of the ultrahigh-pressure Dabie-Sulu Orogen. Tectonics, 25, TC5006, Healy, B., Collins, W.J., Richards, S.W., 2004. A hybrid origin for Lachlan S-type granites: The Murrumbidgee batholith example. Lithos, 79, 197–216. Hoskin, P.W.O., Schaltegger, U., 2003. The composition of zircon and igneous and metamorphic petrogenesis: Reviews in Mineralogy and Geochemistry, 53,27–62. Hu, P.Y., Zhai, Q.G., Wang, J., Tang, Y., Ren, G.M., 2017. The Shimian ophiolite in the western Yangtze Block, SW China: Zircon SHRIMP U-Pb ages, geochemical and Hf-O isotopic characteristics, and tectonic implications. Precambrian Research, 298, 107–122. Huang, X.L., Xu, Y.G., Li, X.H., Li, W.X., Lan, J.B., Zhang, H.H., Liu, Y.S., Wang, Y.B., Li, H.Y., Luo. Z.Y., Yang, Q.J., 2008. Petrogenesis and tectonic implications of Neoproterozoic, highly fractionated A-type granites from Mianning, South China. Precambrian Research, 165(3–4), 190–204. Huang, X.L., Xu, Y.G., Lan, J.B., Yang, Q.J., Luo, Z.Y., 2009. Neoproterozoic

adakitic rocks from Mopanshan in the Western Yangtze craton: partial melts of a thickened lower crust. Lithos, 112(3), 367–381. Huang, S.F., Wang, W., Pandit, M.K., Zhao, J.H., Lu, G.M., Xue, E.K., 2019. Neoproterozoic S-type granites in the western Jiangnan Orogenic Belt, South China: Implications for petrogenesis and geodynamic significance. Lithos, 342–343, 45-58. IIes, K.A., Hergt, J.M., Woodhead, J.D., 2018. Modelling isotopic responses to disequilibrium melting in granitic systems. Journal of Petrology, 59(1), 87–114. Johannes, W., Holtz, F., 1996. Petrogenesis and Experimental petrology of Granitic rocks. Springer, Berlin, pp. 1–335. Jiang, Y.D., Sun, M., Zhao, G.C., Yuan, C., Xiao, W.J., Xia, X.P., Long, X.P., Wu, F.Y., 2010. The 390 Ma high-T metamorphism in the Chinese Altai: consequence of ridge-subduction ? American Journal of Sciences, 310 (10), 1421–1452. Jiang, Y.H., Zhu, S.Q., 2017. Petrogenesis of the Late Jurassic peraluminous biotite

granites

and

muscovite-bearing

granites

in

SE

China:

geochronological, elemental and Sr-Nd-O-Hf isotopic constraints. Contribution to Mineral and Petrology, 172, 1–27. Keay S., Collins W.J., McCulloch M.T., 1997. A three component Sr–Nd isotopic mixing model for granitoid genesis, Lachlan fold belt, eastern Australia. Geology 25, 307–310. Kemp, A.I.S., Hawkesworth, C.J., Foster, G.L., Paterson, B.A., Woodhead, J.D., Hergt, J.M., Gray, C.M., Whitehouse, M.J., 2007. Magmatic and crustal differentiation history of granitic rocks from Hf–O isotopes in zircon. Science, 315, 980–983. Kong, X.Y., Zhang, C., Liu, D.D., Jiang, S., Luo, Q., Zeng, J.H., Liu, L.F., Luo, L., Shao, H.B., Liu, D., Liu, X.Y., Wang, X.P., 2019. Disequilibrium partial melting of metasediments in subduction zones: Evidence from O-Nd-Hf isotopes and trace elements in S-type granites of the Chinese Altai.

Lithosphere, 11(1), 149–168. Lai, S.C., Qin, J.F., Zhu, R.Z., Zhao, S.W., 2015a. Neoproterozoic quartz monzodiorite–granodiorite association from the Luding–Kangding area: implications for the interpretation of an active continental margin along the Yangtze Block (South China Block). Precambrian Research, 267(3–4), 196–208. Lai, S.C., Qin, J.F., Zhu, R.Z., Zhao, S.W., 2015b. Petrogenesis and tectonic implication of Neoproterozoic peraluminous granitoids from the Tianquan area, western Yangtze Block, South China. Acta Petrologica Sinica, 31(8), 2245–2258 (in Chinese with English abstract). Li, J.Y., Wang, X.L., Gu, Z.D., 2018. Petrogenesis of the Jiaoziding granitoids and associated basaltic porphyries: implications for extensive early Neoproterozoic arc magmatism in western Yangtze block. Lithos, s296–299, 547–562. Li, Q.W., Zhao, J.H., 2018. The Neoproterozoic high-Mg dioritic dikes in south china formed by high pressures fractional crystallization of hydrous basaltic melts. Precambrian Research, 309, 198–211. Li, X.H., Li, Z.X., Ge, W.C., Zhou, H.W., Li, W.X., Liu, Y., Wingate, M.T.D., 2003. Neoproterozoic granitoids in South China: Crustal melting above a mantle plume at ca. 825 Ma? Precambrian Research, 122(1–4), 45–83. Li, X.H., Li, Z.X., Sinclair, J.A., Li, W.X., Carter, G., 2006. Revisiting the “Yanbian Terrane”: Implications for Neoproterozoic tectonic evolution of the western Yangtze block, South China. Precambrian Research, 151(1–2), 14–30. Li, Z.X., Bogdanova, S.V., Collins, A.S., Davidson, A., De Waele, B., Ernst, R.E., Fitzsi-mons, I.C.W., Fuck, R.A., Gladkochub, D.P., Jacobs, J., Karlstrom, K.E., Lu, S., Natapov, L.M., Pease, V., Pisarevsky, S.A., Thrane, K., Vernikovsky, V., 2008. Assembly, configuration, and break-up history of Rodinia: a synthesis. Precambrian Research, 160, 179–210. Liu, X.M., Gao, S., Diwu, C.R., Yuan, H.L., Hu, Z.C., 2007. Simultaneous

in-situ determination of U-Pb age and trace elements in zircon by LA-ICP-MS in 20 μm spot size. Chinese Science Bulletin, 52(9), 1257–1264. Liu, Y., Liu, X.M., Hu, Z.C., Diwu, C.R., Yuan, H.L., Gao, S., 2007. Evaluation of accuracy and long-term stability of determination of 37 trace elements in geological samples by ICP-MS. Acta Petrologica Sinica, 23(5), 1203–1210. (in Chinese with English abstract). Liu H., Zhao J.H., 2018. Neoproterozoic peraluminous granitoids in the Jiangnan Fold Belt: Implications for lithospheric differentiation and crustal growth. Precambrian Research, 309, 152–165. Ludwig, K.R., 2003. ISOPLOT 3.0: A geochronological toolkit for Microsoft Excel. Berkeley Geochronology Center, Special Publication, No. 4. Mcleod, C.L., Davidson, J.P., Nowell, G.M., De Silva, S.L., 2012. Disequilibrium melting during crustal anatexis and implications for modeling open magmatic systems. Geology, 40(5), 435–438. Moyen, J.F., Martin, H., 2012. Forty years of TTG research. Lithos, 148, 312–336. Meng, E., Liu, F.L., Du, L.L., Liu, P.H., Liu, J. H., 2015. Petrogenesis and tectonic significance of the Baoxing granitic and mafic intrusions, southwestern china: evidence from zircon U–Pb dating and Lu–Hf isotopes, and whole-rock geochemistry. Gondwana Research, 28(2), 800–815. Munteanu, M., Wilson, A., Yao, Y., Harris, C., Chunnett, G., Luo, Y., 2010. The Tongde dioritic pluton (Sichuan, SW China) and its geotectonic setting: regional implications of a local-scale study. Gondwana Research, 18(2), 455–465. Niu Y.L., O’Hara M.J., Pearce J.A., 2003. Initiation of subduction zones as a consequence of lateral compositional buoyancy contrast within the lithosphere: a petrological perspective. Journal of Petrology, 44, 851–866.

Nowell, G.M., Kempton, P.D., Noble, S.R., Fitton, J.G., Saunders, A.D., Mahoney,

J.J.,

Taylor,

R.N.,

1998.

High

precision

Hf

isotope

measurements of MORB and OIB by thermal ionisation mass spectrometry: insights into the depleted mantle. Chemical Geology, 149(3–4), 211–233. Patiňo Douce, A.E., 1995. Experimental generation of hybrid silicic melts by reaction of high-Al basalt with metamorphic rocks. Journal of Geophysical Research Solid Earth, 100, 15623–15639. Patiňo Douce, A.E., 1996. Effects of pressure and H2O content on the compositions of primary crustal melts. Transaction of the Royal Society of Edinburgh, Earth Science, 87, 11–21. Patiño Douce, A.E., 1999. What do experiments tell us about the relative contributions of crust and mantle to the origin of the granitic magmas. Geological Society London Special Publications, 168(1), 55–75. Patiňo Douce, A.E., Johnston, A.D., 1991. Phase equilibria and melt productivity in the pelitic system: implications for the origin of peraluminous granitoids and aluminous granulites. Contributions to Mineralogy and Petrology, 107, 202–218. Rapp, R.P., Watson, E.B., 1995. Dehydration melting of metabasalt at 8–32 kbar: implications for continental growth and crust-mantle recycling. Journal of Petrology, 36(4), 891–931. Rossi, J.N., Toselli, A.J., Saavedra, J., Sial, A.N., Pellitero, E., Ferreira, V.P., 2002. Common crustal sources for contrasting peraluminous facies in the early Paleozoic Capillitas Batholith, NW Argentina. Gondwana Research. 5, 325–337. Rudnick, R.L., Gao, S., 2003. Composition of the continental crust. Treatise Geochem, 3, 1–64. Sichuan Provincial Bureau of Geology and Mineral Resources (SPBGMR), 1966. Regional geological survey of People's Republic of China, the Miyi Sheet map and report, scale 1: 200,000. (in Chinese)

Sisson, T.W., Ratajeski, K., Hankins, W.B., Glazner, A.F., 2005. Voluminous granitic magmas from common basaltic sources. Contributions to Mineralogy and Petrology, 148, 635–661. Soderlund, U., Patchett, P.J., Vervoort, J.D., Isachsen, C.E., 2004. The

176

Lu

decay constant determined by Lu–Hf and U–Pb isotope systematics of Precambrian mafic intrusions. Earth and Planetary Science Letters, 219(3–4), 311–324. Sun, S.S., and McDonough, W.F., 1989, Chemical and isotopic systematics of oceanic basalts; implications for mantle composition and processes. In: Saunders, A.D., Norry, M.J. eds., Magmatism in the Ocean Basins. Geological Social Lond Special Publication, 42, 313–345. Sun, W.H., and Zhou, M.F., 2008. The ~860 Ma, cordilleran-type Guandaoshan dioritic pluton in the Yangtze Block, SW China: implications for the origin of Neoproterozoic magmatism. Journal of Geology, 116(3), 238–253. Sun, W.H., Zhou, M.F., Zhao, J.H., 2007. Geochemistry and Tectonic Significance of Basaltic Lavas in the Neoproterozoic Yanbian Group, Southern Sichuan Province, Southwest China. International Geology Review, 49(6), 554–571. Sun, W.H., Zhou, M.F., Yan, D.P., Li, J.W., Ma, Y.X., 2008. Provenance and tectonic setting of the Neoproterozoic Yanbian Group, western Yangtze Block (SW China). Precambrian Research, 167(s1–2), 213–236. Sylvester, P.J., 1998. Post-collisional strongly peraluminous granites. Lithos, 45, 29–44. Tang, M., Wang, X.L., Shu, X.J., Wang, D., Yang, T., Gopon, P., 2014. Hafnium

isotopic

heterogeneity

in

zircons

from

granitic

rocks:

geochemical evaluation and modeling of “zircon effect” in crustal anatexis. Earth and Planetary Science Letters, 389, 188–199. Tompson, A.B., 1996. Fertility of crustal rocks during anataxis. Transactions of the Royal Society of Edinburgh, Earth Sciences, 87, 1–10.

Vernon, R.H., 1984. Microgranitoid enclaves in granites—globules of hybrid magma quenched in a plutonic environment. Nature, 309, 438–439. Vielzeuf, D., Schmidt, N.W., 2001. Melting relations in hydrous systems revisited: applications to metapelites, metagreywackes and metabasalts. Contribution to Mineralogy and Petrology, 141, 251–267. Villaros, A., Buick, I.S., Stevens, G., 2012. Isotopic variations in S-type granites: an inheritance from a heterogeneous source? Contributions to Mineralogy and Petrology, 163(2), 243–257. Wang, D., Wang, X.L., Cai, Y., Goldstein, S.L., Yang, T., 2018. Do Hf isotopes in magmatic zircons represent those of their host rocks? Journal of Asian Earth Sciences, 154, 202–212. Wang, X.L., Zhou, J.C., Wan, Y.S., Kitajima, K., Wang, D., Bonamici, C., Qiu, J.S., Sun, T., 2013. Magmatic evolution and crustal recycling for Neoproterozoic strongly peraluminous granitoids from Southern China: Hf and O isotopes in zircon. Earth and Planetary Science Letters, 366(2), 71–82. Wang, X.L., Zhou, J.C., Griffin, W.L., Zhao, G.C., Yu, J.H., Qiu, J.S., Zhang, Y.J.,

and

Xing,

G.F.,

2014.

Geochemical

zonation

across

a

Neoproterozoic orogenic belt: isotopic evidence from granitoids and metasedimentary rocks of the Jiangnan orogen, China. Precambrian Research, 242(2), 154–171. Wang, Y.J., Zhou, Y.Z., Cai, Y.F., Liu, H.C., Zhang, Y.Z., and Fan, W.M., 2016. Geochronological and geochemical constraints on the petrogenesis of the Ailaoshan granitic and migmatite rocks and its implications on Neoproterozoic subduction along the SW Yangtze Block. Precambrian Research, 283, 106–124. Watson E.B., Harrison T.M., 1983. Zircon saturation revisited: temperature and composition effects in a variety of crustal magma types. Earth and Planetary Science Letters, 64, 295–304. Wiedenbeck, M., Hanchar, J.M., Peck, W.H., Sylvester, P., Valley, J.,

Whitehouse, M., Kronz, A., Morishita, Y., et al., 2004. Further characterisation of the 91500 zircon crystal. Geostandards and Geoanalytical Research, 28(1), 9–39. Yang J.H., Wu F.Y., Wilde S., Xie L.W., Yang Y.H., Liu X.M., 2007. Tracing magma mixing in granite genesis: in situ U–Pb dating and Hf-isotope analysis of zircons. Contribution to Mineralogy and Petrology, 153, 177–190. Yang, Y.J., Zhu, W.G., Bai, Z., Zhong, H., Ye, X.T., Fan, H.P., 2016. Petrogenesis and tectonic implications of the Neoproterozoic Datian mafic–Ultramafic dykes in the Panzhihua area, western Yangtze block, SW China. International Journal of Earth Sciences, 106 (1), 1–29. Yuan, H.L., Gao, S., Liu, X.M., Li, H.M., Gunther, D., Wu, F.Y., 2004. Accurate U–Pb age and trace element determinations of zircon by laser ablation-inductively coupled plasma mass spectrometry. Geostandards & Geoanalytical Research, 28(3), 353–370. Yuan, H.L., Gao, S., Dai, M.N., Zong, C.L., Gunther, D., Fontaine, G.H., Liu, X.M., Diwu, C.R., 2008. Simultaneous determinations of U–Pb age, Hf isotopes and trace element compositions of zircon by excimer laser-ablation quadrupole and multiple-collector ICPMS. Chemical Geology, 247(1–2), 100–118. Zeng, L.S., Asimow, P.D., Saleeby, J.B., 2005a. Coupling of anatectic reactions and dissolution of accessory phases and the Sr and Nd isotope systematics of anatectic melts from a metasedimentory source. Geochimica Et Cosmochimica Acta, 69, 3671–3682. Zeng, L.S., Saleeby, J.B., Asimow, P., 2005b. Nd isotopic disequilibrium during crustal anatexis: a record from the Goat Ranch migmatite complex, southern Sierra Nevada batholith, California. Geology, 33, 53–56. Zhao, G.C., and Cawood, P.A., 2012. Precambrian geology of china. Precambrian Research, s 222–223, 13–54. Zhao, J.H., and Zhou, M.F., 2007a. Geochemistry of Neoproterozoic mafic

intrusions in the Panzhihua district (Sichuan Province, SW China): Implications for subduction-related metasomatism in the upper mantle: Precambrian Research, 152(1), 27–47. Zhao, J.H., and Zhou, M.F., 2007b. Neoproterozoic Adakitic Plutons and Arc Magmatism along the western Margin of the Yangtze Block, South China. Journal of Geology, 115(6), 675–689. Zhao, J.H., Zhou, M.F., Yan, D.P., Yang, Y.H., Sun, M., 2008a. Zircon Lu–Hf isotopic constraints on Neoproterozoic subduction-related crustal growth along the western margin of the Yangtze Block, South China. Precambrian Research, 163(3), 189–209. Zhao, J.H., Zhou, M.F., Zheng, J.P., and Fang, S.M., 2010. Neoproterozoic crustal growth and reworking of the Northwestern Yangtze Block: Constraints from the Xixiang dioritic intrusion, South China. Lithos, 120(3–4), 439–452. Zhao, J.H., Zhou, M.F., Yan, D.P., Zheng, J.P., Li, J.W., 2011. Reappraisal of the ages of Neoproterozoic strata in South China: No connection with the Grenvillian orogeny. Geology, 39(4), 299–302. Zhao, J.H., Zhou, M.F., Zheng, J.P., 2013, Constraints from zircon U–Pb ages, O and Hf isotopic compositions on the origin of Neoproterozoic peraluminous granitoids from the Jiangnan fold belt, south China. Contributions to Mineralogy and Petrology, 166(5), 1505–1519. Zhao, J.H., Asimow, P.D., Zhou, M.F., Zhang, J., Yan, D.P., Zheng, J.P., 2017. An

Andean-type

arc

system

in

Rodinia

constrained

by

the

Neoproterozoic Shimian ophiolite in south china. Precambrian Research, 296, 93–111. Zhao, J.H., Li, Q.W., Liu, H., Wang, W., 2018. Neoproterozoic magmatism in the western and northern margins of the Yangtze Block (South China) controlled by slab subduction and subduction-transform-edge-propagator. Earth-Science Reviews, 187, 1–18. Zhao, X.F., Zhou, M.F., Li, J.W., Wu, F.Y., 2008b. Association of

Neoproterozoic A- and I-type granites in south china: implications for generation of A-type granites in a subduction-related environment. Chemical Geology, 257(s1), 1–15. Zhao Z.F., Gao P., Zheng Y.F., 2015. The source of Mesozoic granitoids in South China: Integrated geochemical constraints from the Taoshan batholith in the Nanling Range. Chemical Geology, 395, 11–26. Zheng, J.P., Griffin, W.L., O’Reilly, S.Y., Zhang, M., Pearson, N., Pan, Y.M., 2006. Widespread Archean basement beneath the Yangtze craton. Geology, 34, 417–420. Zheng, Y.F., Wu, Y.B., Zhao, Z.F., Zhang, S.B., Xu, P., Wu, F.Y., 2005. Metamorphic effect on zircon Lu–Hf and U–Pb isotope systems in ultrahigh-pressure eclogite-facies metagranite and metabasite. Earth and Planetary Science Letters, 240(2), 378–400. Zheng, Y.F., Zhang, S.B., Zhao, Z.F., Wu, Y.B., Li, X.H., Li, Z.X., Wu, F.Y., 2007. Contrasting zircon Hf and O isotopes in the two episodes of Neoproterozoic granitoids in South China: implications for growth and reworking of continental crust. Lithos, 96, 127–150. Zhou, M.F., Yan, D., Kennedy, A.K., Li, Y.Q., Ding, J., 2002. SHRIMP U–Pb zircon geochronological and geochemical evidence for Neoproterozoic arc-magmatism along the western margin of the Yangtze Block, South China. Earth and Planetary Science Letters, 196(1–2), 51–67. Zhou, M.F., Yan, D.P., Wang, C.L., Qi, L., Kennedy, A., 2006a. Subduction-related origin of the 750 Ma Xuelongbao adakitic complex (Sichuan Province, China): Implications for the tectonic setting of the giant Neoproterozoic magmatic event in South China. Earth and Planetary Science Letters, 248, (1–2), 286–300. Zhou, M.F., Ma, Y.X., Yan, D.P., Xia, X.P., Zhao, J.H., S, M., 2006b. The Yanbian

Terrane

(Southern

Sichuan

Province,

SW

China):

A

Neoproterozoic arc assemblage in the western margin of the Yangtze Block. Precambrian Research, 144(1–2), 19–38.

Zhu G.Z., Gerya T.V., Yuen D.A., Honda S., Yoshida T., Connolly J.A.D., 2009. Three-dimensional dynamics of hydrous thermal-chemical plumes in oceanic subduction zones. Geochemistry. Geophysics. Geosystem. 10, Q11006. Zhu, R.Z., Lai, S.C., Qin, J.F., Zhao, S.W., Santosh, M., 2018. Strongly peraluminous fractionated S-type granites in the Baoshan Block, SW China: Implications for two-stage melting of fertile continental materials following the closure of Bangong-Nujiang Tethys. Lithos, 316–317, 178–198. Zhu, W.G., Zhong, H., Li, X.H., Deng, H.L., He, D.F., Wu, K.W., Bai, Z.J., 2008. SHRIMP zircon U–Pb geochronology, elemental, and Nd isotopic geochemistry of the Neoproterozoic mafic dykes in the Yanbian area, SW China: Precambrian Research, 164(1–2), 66–85. Zhu, W.G., Zhong, H., Li, Z.X., Bai, Z.J., Yang, Y.J., 2016. SIMS zircon U–Pb ages, geochemistry and Nd–Hf isotopes of ca. 1.0 Ga mafic dykes and volcanic rocks in the Huili area, SW China: origin and tectonic significance. Precambrian Research, 273, 67–89. Zhu, Y., Lai, S.C., Zhao, S.W., Zhang, Z.Z., Qin, J.F., 2017. Geochemical characteristics and geological significance of the Neoproterozoic K-feldspar granites from the Anshunchang, Shimian area, Western Yangtze Block. Geological Review, 63(5), 1193–1208 (in Chinese with English abstract). Zhu, Y., Lai, S.C., Qin, J.F., Zhu, R.Z., Zhang, F.Y., Zhang, Z.Z., 2019a. Geochemistry and zircon U–Pb–Hf isotopes of the 780 Ma I-type granites in the western Yangtze Block: Petrogenesis and crustal evolution. International Geology Review, 61(10), 1222–1243. Zhu, Y., Lai, S.C., Qin, J.F., Zhu, R.Z., Zhang, F.Y., Zhang, Z.Z., Gan, B.P., 2019b. Petrogenesis and geodynamic implications of Neoproterozoic gabbro-diorites,

adakitic

granites,

and

A-type

granites

in

the

southwestern margin of the Yangtze Block, South China. Journal of

Asian Earth Sciences. https://doi.org/10.1016/j.jseaes.2019.103977. Zimmer, M., Kroner, A., Jochum, K.P., Reischmann, T., Todt, W., 1995. The Gabal Gerf complex: A Precambrian N-MORB ophiolite in the Nubian Shield, NE Africa. Chemical Geology 123, 29–51. Figure captions Fig. 1 Sketch geological map of the Yangtze Block, South China (modified after Gan et al., 2017; Zhao et al., 2017). Fig. 2 Geological map of the western margin of Yangtze Block (2a) (modified after Zhou et al., 2006b) and regional geological map of the Kuanyu and Cida pluton (2b) (revised from the Miyi 1:200000 geological map, SPBGMR, 1966). Fig. 3 Field and hand specimen photographs as well as representative microscope photographs of the Kuanyu (3a, 3c, 3e) and Cida (3b, 3d, 3f) granites from the western margin of the Yangtze Block, South China. Mineral abbreviations:

Pl-plagioclase;

Kfs-K-feldspar;

Per-perthite;

Qtz-quartz; Bi-biotite; Mag-magnetite. Fig. 4 LA-ICP-MS U-Pb zircon concordia diagrams for the Kuanyu (4a-b) and Cida (4c-f) granites from the western margin of the Yangtze Block, South China. Fig. 5 The A/NK versus A/CNK diagram (5a), (Na2O + K2O - CaO) versus SiO2 (5b) (Frost et al., 2001), K2O/Na2O versus SiO2 (5c) (Moyen and Martin, 2012), Mg# versus SiO2 (5d) diagrams for the Kuanyu and Cida peraluminous granites from western margin of the Yangtze Block, South

China. The Neoproterozoic juvenile mafic lower crust-derived granitoids were shown for comparison. The Kangding granitoids are from Lai et al. (2015a). The Dalu I-type granitoids are from Zhu et al. (2019a). In Fig. 5d, also shown are the fields of pure crustal partial melts determined in experimental studies on dehydration melting of two-mica schist at 7–10 kbar, 825–850 ℃ (Patiňo Douce and Johnston, 1991), of dehydration melting of low-K basaltic rocks at 8–16 kbar, 1000–1050 ℃ (Rapp and Watson, 1995), and of moderately hydrous (1.7–2.3 wt.% H2O) mediumto high-K basaltic rocks at 7 kbar, 825–950 ℃ (Sisson et al., 2005). Fig. 6 Harker diagrams of major elements for the Kuanyu and Cida peraluminous granites from the western Yangtze Block, South China. The shaded areas denote the experimental melts at crustal conditions (referred from Guo et al., 2012). Symbols as Fig. 5. Fig. 7 Diagrams of chondrite-normalized REE patterns (7a, 7c) and primitive mantle-normalized trace element patterns (7b, 7d) for the Kuanyu and Cida peraluminous granites from the western margin of the Yangtze Block, South China. The primitive mantle and chondrite values are from Sun and McDonough (1989). The lower, middle, and upper continental crust references are from Rudnick and Gao (2003). The Kangding granitoids are from Lai et al. (2015a). The Dalu I-type granitoids are from Zhu et al. (2019a). Fig. 8 Initial Sr-Nd isotopic compositions for the Neoproterozoic Kuanyu and

Cida peraluminous granites in the western Yangtze Block, South China (revised after Wang et al., 2016). The Neoproterozoic mantle-derived mafic rocks in the western Yangtze Block are from Zhao et al. (2008a); Zhou et al. (2006b); Zhao and Zhou (2007a). The Neoproterozoic juvenile mafic lower crust-derived granitoids in the western Yangtze Block are from Huang et al. (2008, 2009); Lai et al. (2015a); Li and Zhao (2017); Zhao and Zhou (2007b); Zhao et al. (2008a, 2008b); Zhou et al. (2006a); Zhu et al. (2019a). The Neoproterozoic Ailaoshan granitic and migmatite rocks in the southwestern Yangtze Block are from Wang et al. (2016). The Neoproterozoic depleted mantle is from Zimmer et al. (1995). The Kongling basement in Yangtze Block is from Gao et al. (1999) and Zhang. (2008). Fig. 9 The εHf(t) values versus Zircon U-Pb age diagram for the Neoproterozoic Kuanyu and Cida peraluminous granites from the Yangtze Block, South China (revised after Zhao et al., 2013). Zircon Hf isotopic data of Neoproterozoic mantle-derived mafic rocks in the western Yangtze Block are from Sun and Zhou (2008); Zhao et al. (2008a). Neoproterozoic juvenile mafic lower crust-derived granitoids in the western Yangtze Block are from Huang et al. (2008, 2009); Zhao et al. (2008b); Zhu et al. (2019a). Neoproterozoic Ailaoshan granitic and migmatite rocks in the southwestern Yangtze Block are from Wang et al. (2016). Neoproterozoic peraluminous granites in Jiangnan fold belt,

South China are from Zhao et al. (2013). The Kongling basement is from Gao et al. (2011). Fig. 10 Histograms of εHf(t) isotope ratios and Hf model age for the Kuanyu (6a, 6b) and Cida (6c-f) peraluminous granites from the western margin of the Yangtze Block, South China. Fig. 11 The CaO/Al2O3 versus CaO + Al2O3 (11a) (Patiño Douce, 1999), Al2O3/(Fe2O3T +MgO +TiO2) versus Al2O3 + Fe2O3T +MgO +TiO2 (11b) (Patiño Douce, 1999), CIPW-normative Qz-Ab-Or (11c) (Johannes and Holtz, 1996), and zircon saturation temperature versus A/CNK (11d) diagrams for the Kuanyu and Cida peraluminous granites from the western margin of the Yangtze Block, South China. Symbols as Fig. 5. Fig. 12 The CaO/Na2O versus Al2O3/TiO2 (12a) (Sylvester, 1998), Rb/Ba versus Rb/Sr (12b) (Patiño Douce, 1999), and molar Al2O3/(MgO + FeOT) versus molar CaO/(MgO + FeOT) (12c) (Altherr et al., 2000) diagrams for the Kuanyu and Cida peraluminous granites from the western Yangtze Block, South China. Symbols as Fig. 5. Fig. 13 The La/Sm versus Th/Sc, initial

87

Sr/86Sr (Isr) versus 1/Sr, and εNd(t)

versus SiO2 diagrams for the Kuanyu and Cida peraluminous granites from the western Yangtze Block, South China. Symbols as Fig. 5. Fig. 14 The schematic diagram for the generation of Kuanyu and Cida peraluminous granites in the western margin of the Yangtze Block, South China (modified after Chen et al., 2014) (a), and the detailed comparison

on the zircon U-Pb age and Hf isotopes of the Neoproterozoic magmatism from the western Yangtze Block (b). Table Captions Table1 Concordant results of zircon U-Pb dating for the Neoproterozoic Kuanyu and Cida peraluminous granites from the western margin of the Yangtze Block, South China. Table 2 The major (wt %) and trace (ppm) elements for the Neoproterozoic Kuanyu and Cida peraluminous granites in the western Yangtze Block, South China. Table 3 Whole-rock Sr-Nd isotopes data for the Neoproterozoic Kuanyu and Cida peraluminous granites in the western Yangtze Block, South China. Table. 4 Zircon Lu-Hf isotopic data for the Neoproterozoic Kuanyu and Cida peraluminous granites along the western margin of the Yangtze Block, South China.

Table 1 Concordant results of zircon U-Pb dating for the Neoproterozoic Kuanyu and Cida peraluminous granites from the western margin of the Yangtze Block, South China.

content(pp ratios

A

ages(Ma)

m) na T

207

h

Pb

2

Pb

2

Pb

2

Pb

/

/206

σ

/23

σ

/23

σ

/232

U

Pb

207

206

208

207

207

206

208

2

Pb

2 Pb

2 Pb

2

Pb

2

σ

/206

σ /23

σ /23

σ /232

σ

Pb

5U

8U

Th

ly T si

U h

s 5U

8U

Th

KY-2 0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

6 4 8 K

9. 6.

Y-

4

0

0.0

1

27

7

13

1

0.0

0

4

1

7

65

4

34

0

99

5

46

4

80

5 83

8 84

99

4

5

1

9

1

15

9

6

4

5

1 2-

8

9

91

0

5 01

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0

0

2

9 9 7 K

9. 5.

Y-

4

1

0.0

1

26

6

0.

1

0.0

0

4

1

0

65

4

27

3

13

4

39

5

80

5 82

7 84

85

2

8

2

91

9

71

8

2

9

0

0.0

0.

1.

0.

0.

0.

0.0

0.

80

4 82

9 83

0 2-

9

8

78

1

9 02 K

1

3

0

7 9

85

1

Y-

0

9

.

66

0

25

0

13

0

43

0

2-

1.

5.

2

07

0

72

1

80

0

36

0

03

5

1

6

1

2

9

3

1

0

9

8

1

5

8

5

7

5

9

3

2

0.

0.

0.

0.

0

0

0 0

9

8

7

4

8

4

1 9

0

0

0

.

0

1.

1

0.

0

8.

0

0.0

1

26

4

13

1

0.0

0

4

6

66

3

99

6

88

4

43

5

81

3 83

7 83

35

8

3

3

3

7

75

1

8

2

8

1 K 3. Y-

4

1

6 2-

8

86

0

0 04

9

1 1

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

3. 2

0.0

1

26

9

13

1

0.0

0

2

65

5

84

2

96

5

42

5

80

8 83

9 84

1

87

2

3

7

9

4

54

2

2

2

3

9

84

0

3

05 1

4

2

23

0.

1

Y2

0.

5

K 5.

0.

6

7

0.

0.

0.

0. 0

2

0 K

1

4

0

1.

0

0.

0

0.0

0

30

1

14

0

0.0

0

67

1

69

8

01

1

42

0

85

5 84

8 84

66

5

9

1

2

5

99

6

8

9

5

. Y-

6.

7.

2-

0

8

4

1

1 9

85

6 07

5

3

1

3

1 1

2

5

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

4 1

K 7.

4.

4

9

Y25

3

2

0.0

1

28

8

14

1

0.0

0

8

66

5

04

9

04

5

43

5

81

7 83

8 84

2

15

1

8

5

2

4

34

8

1

7

7

0.

0.

0.

0.

0

0

0

0

0

.

0

2

0.

0

0

3

0.0

1

1.

0

13

1

0.0

0

3

7

65

5

25

3

96

5

41

5

77

9 82

9 84

06

5

27

8

6

6

34

5

6

5

3

9

81

1

0.

0.

0

0

0

.

0

1.

1

9

0. 0.

0

0.

0

0

3 8. 1

0.0

1

28

6

13

0

0.0

0

4

6

67

4

91

7

93

1

41

4

84

4 84

7 84

12

5

7

2

3

5

06

2

1

1

1

6

23

1

8

Y8

4

2

K 7.

8

1

09

1

1

8.

20

85

3

Y5

9

3

K 3.

1

6

08

1

4

8

81

8

2

10 K

1

9

0

0.0

0.

1.

0.

0.

0.

0.0

0.

Y-

4

5

.

66

0

27

0

13

0

44

0

81

4 83

7 84

2-

0.

9.

1

41

0

80

1

96

0

97

0

9

6

2

3

4

1 8

88 9

2

11

7

0

4

4

1

7

4

1

K 5.

6

1

0

4

4

5

6

3

4

1

0.

0.

0.

0

0

0

.

0

1.

1

4

4

1

26

7

13

0

0.0

0

0

66

4

11

2

85

1

41

4

80

5 82

8 83

01

6

4

4

8

5

38

6

7

8

7

0.

0.

0

0

0

.

0

1.

1

1

9

0

0. 0.

0

0.

0

0

2

0.0

1

25

7

13

0

0.0

0

6

66

4

81

3

82

1

46

5

80

6 82

8 83

01

6

2

7

4

5

67

6

7

7

5

0.

0.

0.

0.

4

1 8

92

1

0

0

0

0

0

.

0

1.

1

0.

0

0

2

5 1 2. 2

0.0

1

28

7

14

1

0.0

0

4

9

66

4

64

5

00

5

42

4

82

5 84

8 84

62

7

7

4

7

1

53

8

6

0

5

0.0

0.

1.

0.

0.

0.

0.0

0.

79

4 82

7 84

7 9

84

9

9

14 K

82

6

28

8

6

Y5

4

7.

K 7.

0

0.0

13

1

0

6

27

0.

5

Y3

0

5

K 7.

0.

2

12

1

4

8

22

1

7.

Y3

5

1

0

2 8

80

9

Y-

6

7

.

65

0

26

0

13

0

40

0

2-

3.

1

1

67

0

23

1

94

0

42

0

15

2

0.

0

1

5

4

3

1

0

7

6

3

6

4

4

8

7

1

7

9

0.

0.

0

0

0

.

0

1.

2

1 7

1

1

0. 0.

0

0.

0

0

6. 3

0.0

1

25

3

13

0

0.0

0

5

65

6

27

5

85

1

39

6

58

8

3

7

5

6

44

3

5

1

1

79

3 82

1 83

3

5

7

8

29

9

9

Y7

3

4

K 1.

6

9

78

2

2

16 2

0.

0.

0.

0.

0

0

0 0

2

1 1

0

0

5

.

0

1.

1

0.

0

3.

0

0.0

1

26

5

13

1

0.0

0

6

8

65

3

03

2

87

4

40

4

80

4 82

7 83

9

9

8

4

3

7

43

8

3

8

8

7 K 2. Y-

4

6 2-

8

80

9

7 17

7 1

4

0.

0.

0.

0. 0

1

0 K

7

3

0

1.

0

0.

0

0.0

0

25

1

13

0

0.0

0

65

1

50

3

87

1

37

0

79

2 82

6 83

6

3

6

9

7

4

37

3

4

6

8

. Y-

2.

0

2-

7

7.

4

0 8

74

4 18

9

6

2

7

7

1 7

1

6

6

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

9 7

K 9.

9.

4

6

Y29

5

1

0.0

1

27

6

13

1

0.0

0

8

66

4

48

1

95

4

44

5

81

4 83

7 84

8

29

2

9

1

1

9

44

7

5

5

2

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

3

0.0

1

27

9

13

1

0.0

0

1

2

66

5

51

7

91

5

41

5

82

8 83

9 84

48

5

5

2

3

3

19

6

2

5

0

9

81

1

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

6

7 0. 3

0.0

1

27

9

13

1

0.0

0

4

1

1

66

5

94

8

92

5

40

5

82

8 83

9 84

65

5

5

2

3

4

45

3

7

7

0

0

26

1

6

Y0

4

9

K 1.

9

5

21

2

1

4.

21

87

8

Y7

8

5

K 8.

1

7

20

1

4

9

80

0

6

22 K

2

5

0

0.0

0.

1.

0.

0.

0.

0.0

0.

Y-

1

3

.

66

0

28

0

13

0

42

0

83

8 83

9 84

2-

3.

2.

4

99

0

55

1

91

0

12

0

8

9

0

1

4

1 9

83 4

1

23

4

3

1

0

0

1

9

5 5

8

1

0

6

5

5

7

3

6

0. 2

3

2

6

K 0.

0

.

0

1.

0

2

2

1

28

2

13

1

0.0

0

3

67

6

72

2

93

5

41

0

01

4

3

2

4

7

79

6

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

2

0

0

2

0.0

1

28

1

0.

1

0.0

0

1

67

6

94

4

13

5

56

8

09

2

3

6

94

6

77

6

0.

0.

0.

0.

2

83

0 84

0 84

8

0

1

9

82

2

7

4

1

1

84

9 84

0 84

1

1

1

9

11

6

0

0

0

0

0

.

0

1.

1

0

0

16

9 2 2. 3

0.0

1

27

6

0.

1

0.0

0

4

2

66

4

34

0

13

4

38

4

81

4 83

7 84

31

2

4

9

93

9

14

3

6

4

1

0.0

0.

1.

0.

0.

0.

0.0

0.

80

4 82

8 83

6 8

75

8

8

27 K

1

2

23

1

8

Y7

5

1.

K 3.

0

0.0

26

2

0

8

25

0.

4

Y7

0.

7

K 0.

0

6

25

2

0.

3

28

0

7.

Y4

0.

6

0

7 8

79

1

Y-

3

2

.

65

0

25

0

13

0

39

0

2-

1.

7.

0

8

0

16

1

79

0

94

0

28

0

0

8

1

7

7

8

1

0

2

6

5

5

4

8

8

1

9

2

1

0.

0.

0

0

0.

0

0

.

0

0

0

0

1

0.0

0

1. 3

0.0

1

1.

1

4

1

0

66

5

27

9

0.

5

41

5

81

7 83

9 84

29

2

95

2

14

3

92

6

6

7

5

5

25

3

7

Y1

4

4

K 4.

6

9

0. 2

0

9

83

1

8

29 3

0.

0.

0.

0.

0

0

0 0

0

2 5

0

0

1

.

0

1.

1

0.

0

6.

0

0.0

1

26

4

13

1

0.0

0

9

6

66

3

15

4

86

4

43

5

80

3 82

6 83

01

7

6

3

1

6

51

3

7

9

7

9 K 4. Y-

4

1

6 2-

8

86

0

3 30

2 3

6

0.

0.

0

0

0.

0.

0.

0

0

1

0 K

0

6 .

Y-

7.

4.

2-

0

5

0.0

0

1.

1

13

0

0.0

0

4

1

67

1

29

9

97

1

45

0

85

7 84

9 84

41

5

86

2

3

5

9

7

0

5

3

4 9

90

6 31

9

4

7

5

3 4

6

0.

0.

0

0

0

.

0

1.

1

3

7 0.

7 0.

0

0.

0

0

9

K 7.

9.

2

3

Y20

4

3

0.0

1

27

7

13

0

0.0

0

4

1

7

66

4

77

6

90

1

42

6

82

6 83

8 83

64

8

5

5

7

5

89

1

7

6

9

9

84

2

1

32 1

0.

0.

0.

0.

0

0

0 0

9

3 7

0

0

4

.

0

1.

1

0.

0

8.

1

0.0

1

28

5

13

1

0.0

0

3

0

66

4

38

7

90

4

45

5

83

4 83

7 84

95

2

1

2

9

8

03

9

6

9

0

5 K 1. Y-

4

1

5 2-

8

89

1

4 33

8

3 5

0.

0

0

0

0

0

.

0

1.

1

0

0

9. 2

0.0

1

25

8

0.

1

0.0

0

4

1

9

65

4

13

3

13

5

49

6

79

7 82

8 83

53

9

1

7

85

1

98

2

1

4

6

8

29

0.

7

Y4

0.

4

K 9.

0.

0

9

98

2

3

34 K

5

4

0

0.0

0.

1.

0.

0.

0.

0.0

0.

Y-

4

5

.

66

0

27

0

13

0

42

0

82

8 83

9 83

2-

1.

3.

4

64

0

13

2

83

0

34

0

7

3

5

6

4

1 9

83 8

0

35

2

6

8

8

7

1

4

0

7

1

0

5

0

5

5

7

2

3

1

0.

0.

0.

0

0

0

0

.

0

1.

0.

0.

0

0

1 6 7 1 K

2 0.

Y-

3.

3

0.0

1

28

0

13

1

0.0

0

4

1

6

66

5

54

1

95

5

42

5

83

7 83

8 84

82

3

3

9

3

2

53

2

2

9

2

8 2-

1

9

84

0

1 36

0

2

CD-1

1

2

5

4

C 1.

0.

0.

0

0

0

0

0

.

0

2

0.

0

0

6

0.0

1

1.

1

13

1

0.0

0

3

67

6

29

6

98

5

42

5

15

3

45

6

3

7

8

3

4

02

0 84

0 84

2

3

4

9

84

0

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0

0

7

6. 8

0.0

1

29

8

0.

1

0.0

0

4

5

67

5

27

0

13

5

42

4

86

6 84

8 83

8

1

5

5

83

1

31

4

2

3

5

0

15

84

2

D6

1

5

C 8.

1

1

01

4

5

0

10

0.

0.

D0

0.

9

83

1 8

9

3 9

0.

0.

0.

0

0

0

0

0

.

0

1

0.

0

0

5 6

C 9.

0.

3.

D2

7

2

1

1-

7

0.0

1

1.

8

13

1

0.0

0

1

65

5

23

7

77

5

43

4

77

8 81

9 83

15

1

73

5

6

2

11

8

9

8

2

03

3 4

5

0.

.

0

1.

0

0.

0

7

0.0

0

26

1

13

1

0.0

0

4

3

66

1

21

8

82

5

43

4

81

7 82

8 83

22

5

7

3

4

1

04

7

3

9

5

9

85

9

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

2

6 9 3. 6

0.0

1

26

8

13

1

0.0

0

4

6

66

4

25

0

86

5

43

4

80

6 82

8 83

05

9

2

5

4

1

05

7

8

9

7

0.

0.

0.

4

14

0.

4

D7

3

0

C 6.

0

0

04

4

0

9

6.

19

0

85

6

D2

0.

9

4

C 1.

0.

4

9

85

9

0

05 C

3

6

0

0.

D-

3

2

.

0.0

0

1.

0

13

0

0.0

0

1-

6.

6.

5

67

0

29

1

99

0

43

0

84

6 84

8 84

06

7

8

4

29

1

88

8

9

1

71

0

7

5

5

2

0. 4

1 9

86 5

0

3

0

1

5

6

5

4

2

7

3

9

0.

0.

0.

0.

0

0

0 0

5 0

0

0

0

.

0

1.

1

0.

0

1.

5

0.0

1

24

5

13

1

0.0

0

2

4

65

4

36

7

82

4

45

4

78

5 82

7 83

23

1

8

9

9

8

07

6

2

1

5

3 C 8. D-

4

7 1-

8

89

9

8 07

7

5 7

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

1. 6

0.0

1

23

6

13

1

0.0

0

2

64

4

01

9

76

4

41

4

76

6 81

8 83

82

4

3

9

5

9

77

5

9

4

1

6

0.

0.

0

0

0

.

0

1.

1

7

0. 0.

0

0.

0

0

0. 5

0.0

1

27

7

13

0

0.0

0

4

6

67

4

49

5

78

1

43

4

84

6 83

8 83

1

9

5

1

2

5

67

7

1

5

2 9 83

1

15

9

5

D5

82

6

C 2.

8

1

08

3

4

0

13

0.

3

D1

0.

9

C 4.

0.

1

8

86

9

5

10 C

4

6

0

0.0

0.

1.

0.

0.

0.

0.0

0.

82

4 82

D-

0

7

.

66

0

26

0

13

0

41

0

4

9

9

1

4 9

82

1

6

0

1-

6.

6.

6

12

8

5

0

1

1

3 3

2

1

2

0

1

0

5

1

5

5

8

7

3

1

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

7

0.0

1

24

7

13

1

0.0

0

4

2

65

4

92

3

85

5

42

4

78

6 82

8 83

41

6

3

9

3

1

88

8

8

3

6

9

84

9

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

2

0.

0

0

9

5 0 2. 7

0.0

1

25

6

13

1

0.0

0

4

65

8

31

9

83

6

41

5

68

3

7

6

9

6

16

8

5

1

1

79

7 82

2 83

6

5

6

8

15

0

5

D7

72

7

C 3.

0

4

16

3

76

6.

17

25

8

D6

0

7

C 2.

55

9

81

1

3

17 1

0.

0.

1

0

0

.

0

1

5

9 1

0.

0.

0.

0

0

1 C

0 5.

D-

5.

1-

7

2

0.0

1

1.

7

13

0

0.0

0

4

1

64

4

23

2

80

1

40

0

77

6 81

8 83

93

5

61

1

8

5

04

4

2

7

4

4 9

79

7 18

0

4

8

2 9

0.

0.

0.

0

0

0

0

0

.

0

1.

2

0

0

3 6

C 4.

0.

7.

D3

9

3

2

1-

8

0.0

1

29

0

0.

1

0.0

0

0

68

6

71

7

13

5

43

4

86

8 84

9 83

03

1

2

3

83

4

07

9

9

4

5

21

2 8

0

0

0

0

0.

.

0

1.

2

0.

0

0

6

0.0

1

28

5

13

1

0.0

0

4

4

67

7

10

1

86

6

44

0

02

7

7

8

4

2

62

6

1

83

4 83

1 83

8

7

7

9

88

2

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

2

0

0

2

0 7. 6

0.0

1

27

1

0.

1

0.0

0

5

1

0

66

6

03

1

13

5

44

5

82

0 83

9 83

67

1

4

1

82

5

62

4

8

3

5

0.

0.

0.

7

16

1

4

D7

5

0

C 3.

2

7

22

2

9

9.

18

0.

85

3

D9

0.

9

4

C 2.

0.

4

9

88

0

8

24 C

3

7

0

0.

D-

6

9

.

0.0

0

1.

0

13

0

0.0

0

1-

9.

4.

4

65

0

25

1

81

0

42

0

79

8 82

9 83

26

3

2

7

65

1

06

9

7

1

87

0

5

4

4

2

0. 4

1 9

84 8

0

6

2

1

1

0.

2.

C D-

5

5

4

4

3

2

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0

0

6

0.0

1

26

9

0.

1

0.0

0

4

66

5

53

7

13

5

42

4

81

8 83

9 83

1

41

6

6

4

82

3

94

9

9

0

5

0.

0.

0.

0.

1

0

0

0

0

.

0

1

0.

0

0

0

0.0

1

1.

8

13

1

0.0

0

2

0

67

5

27

1

83

5

40

4

83

6 83

8 83

04

1

88

7

6

1

3

2

9

6

5

79

8

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

2

0.

0

0

9

0 4. 4

0.0

1

33

0

13

1

0.0

0

4

1

5

69

6

04

1

92

5

40

4

90

7 85

9 84

31

1

4

2

2

4

79

9

8

9

0 8 83

5

14

9

5

D4

4

2

C 9.

0

3

28

2

0

0.

14

85

2

D6

9

6

C 7.

1

0

27

6

4

3

17

4

3

0

6

5

9

80

0

4

29 C

7

7

1

0.0

0.

1.

0.

0.

0.

0.0

0.

79

4 82

D-

2

1

.

65

0

25

0

13

0

40

0

0

7

4

6

8 9

80 6

8

1-

0.

9.

0

30

1

7

0

9

0

48

0

06

1

85

0

1

5

8

3

1

0

2

5

4

8

2

2

0.

0.

0.

0

0

0 0

5

69

0

1

1

0

0

0

0.

C

4

6

.

0

1.

2

0.

0

D-

4.

8.

9

0.0

0

29

5

13

1

0.0

0

1-

0

2

8

68

1

00

4

74

6

44

6

31

7

7

07

8

6

5

6

1

93

2

5 4

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

33

0

2

8

1

26

6

13

1

0.0

0

4

2

66

4

07

7

82

4

41

4

81

5 82

8 83

13

5

1

4

6

9

5

2

1

8

5

8

82

8

0.

0.

0

0 0

2

5 0

0

0.

.

0

1.

0

0.

0

1 4. 8

0.0

1

26

1

13

1

0.0

0

4

4

66

5

72

8

83

5

40

4

82

7 83

8 83

45

3

4

9

2

2

62

4

1

1

5

5

17

1

88

7

D8

1

9

6

C 2.

1 83

0.0

0.

3

4 84

7

32

4

87

7.

18

0.

1

4

D4

0.

1

7

C 0.

0.

5

9

80

5 5

8

9 4

0.

0.

0.

1

0

0

0

0

.

0

1.

1

0.

0

0

8 3

C 2.

0.

5.

D2

6

3

4

1-

1

0.0

1

25

6

13

1

0.0

0

3

65

4

38

5

84

4

41

4

79

5 82

7 83

68

4

1

7

6

9

94

1

6

5

6

34

3 6

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

5

0.0

1

26

6

13

1

0.0

0

2

66

4

85

8

75

4

42

4

83

5 83

8 83

88

7

8

8

6

9

99

5

4

2

1

9

0.

0.

0

0 0

1

0

0

0.

.

0

1.

0

0.

0

5. 6

0.0

2

25

3

13

1

0.0

0

4

65

0

83

2

83

7

41

7

99

9

6

8

1

7

99

1

0.

1.

0.

0.

0.

6

1

1

80

5 82

5 83

0

6

7

5

1

3

18

85

7

D3

8

1

C 1.

4

7

0.

1

0

6

35

1

8

4.

12

0.

83

0

D9

0.

8

7

C 5.

0.

4

83

4

4

38 C

1

1

0

D-

0

8

.

0.0

0

24

0

13

0

0.0

0

1-

6.

5.

5

65

0

96

2

82

0

42

0

39

5

5

7

58

1

2

6

1

1

91

0

2

0. 5

1

1

79

7 82

2 83

3

3

5

9

84 9

2

5

5

8

8

6

6

3

6

5

4

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

CD-2

3 5

7 0

C 3.

7.

1

6

D23

5

0.0

1

28

9

13

1

0.0

0

0

67

5

85

1

83

5

40

4

85

8 84

9 83

56

7

9

9

2

1

56

8

5

1

5

9

0.

9.

C D-

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

6

0.0

1

28

9

13

1

0.0

0

2

67

5

94

3

90

5

40

4

84

8 84

9 83

1

2

8

8

C

27

7

6

7

2

2

58

5

6

1

9

7

0.

0.

0.

0

0 0

0

0.

.

0

1.

0

0.

0

6

0.0

0

26

2

13

1

0.0

0

4

66

1

89

0

78

5

41

4

83

9 83

9 83

80

9

4

4

78

6

8

4

2

2

48

9

1

2

2

0.0

0.

1.

0.

0.

0.

0.0

0.

81

4 82

7 83

9

82

9

0

07 C

9

7

28

4

6.

D6

4

1

03

2.

9

5

25

80

4

7

2

9

9

02

3

4

1

0

2 8

80

8

D-

7

0

.

66

0

25

0

13

0

40

0

2-

4.

4

6

11

0

76

1

79

0

52

0

08

9

9.

4

1

2

5

8

1

0

1

0

4

6

4

4

9

3

6

6

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0

0

6 8

6

0.0

1

24

7

0.

1

0.0

0

5

9

65

4

77

5

13

4

42

4

78

7 82

8 83

39

8

6

5

84

9

11

5

7

2

6

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

9

4

0. 7

0.0

1

26

8

13

1

0.0

0

4

0

65

5

03

8

86

5

43

4

80

8 82

8 83

94

2

5

4

4

1

24

6

4

8

7

4 9

85

9

2

11 8

83

8

23

8

3

D6

4

2

C 8.

3

3

09

3

3

5.

24

7

4

D3

5

9

C 1.

0

9

0.

0.

0.

0. 0

6

0 C

2

0

0

1.

0

0.

0

0.0

0

26

1

13

0

0.0

0

66

1

56

6

87

1

40

0

81

5 83

7 83

15

4

9

3

7

4

66

4

1

1

8

. D-

1.

1.

2-

1

1

4

7 8

80

2 12

4

2

6

8

4 1

7

8

0.

0.

0.

0

0

0 0

8 4

0

0.

3

.

0

1.

1

0.

0

9.

7

0.0

0

24

5

13

1

0.0

0

3

3

65

1

19

2

72

4

42

4

79

4 82

7 82

63

4

7

6

7

5

09

2

5

0

9

8 C 7. D-

4

3 2-

8

83

8

4 13

4

4 4

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

9. 7

0.0

1

24

8

13

1

0.0

0

4

65

4

55

1

80

4

42

4

78

7 82

8 83

45

9

2

4

3

9

5

7

9

1

4

7

0.

0.

0.

0.

0

0

0

0

0

.

0

1.

1

0.

0

0

1

5. 7

0.0

1

26

6

13

1

0.0

0

4

4

66

4

42

5

84

4

39

4

81

5 83

7 83

25

5

4

3

2

7

86

1

4

0

6

9

22

9

2

D9

84

9

C 5.

8

7

14

6

4

7

20

0.

9

D0

0.

6

C 8.

0.

3

8

79

8

0

15 C

7

1

0

0.0

0.

1.

0.

0.

0.

0.0

0.

D-

0

0

.

65

0

24

0

13

0

43

0

79

8 82

9 83

2-

0.

0

8

48

0

83

1

82

0

32

0

0

3

5

0

4

1 9

85 7

0

19

2

9.

5

1

4

0

5

8 1

1

0

1

C

8

D-

1

0

2

5

5

3

7

1

1

0.

0.

0.

0.

0

0

0

0

0

9

.

0

1.

1

0.

0

0

1.

7.

9

0.0

1

22

9

13

1

0.0

0

2-

3

9

0

64

5

88

3

77

5

42

4

76

9 81

9 83

20

9

1

72

2

9

5

2

1

39

6

5

4

2

1

4

9

9

0.

0.

0.

0.

0

0

0 0

4 9

83

9

9

8 2

0

0

3

.

0

1.

1

0.

0

2.

9

0.0

1

24

7

13

1

0.0

0

4

1

65

4

27

1

83

4

42

4

78

6 82

8 83

17

5

9

5

2

8

16

6

0

0

5

6 C 7. D-

4

4 2-

8

83

9

6 21

9 1

1

0.

0.

0.

5

3

0

0

0

0

0.

C

9

2

.

0

1.

1

0.

0

0

D-

2.

5.

9

0.0

1

24

6

13

1

0.0

0

2-

6

9

4

65

4

53

8

77

4

39

0

79

6 82

8 83

22

2

0

57

4

4

7

6

7

89

4

3

1

2

C

1

1

0.0

0.

1.

0.

0.

0.

0.0

0.

79

4 82

8 83

1

5

4 8

79

8

1 8

81

9

D-

2

4

.

65

0

25

0

13

0

41

0

2-

2

4

2

52

0

29

1

87

0

16

0

27

9.

6.

0

1

6

6

1

1

0

4

6

4

9

4

4

6

9

4

8

8

4

1

1

0.

0.

0.

0.

6

3

1

0

0

0

0

C

5

7

.

0

1.

1

0.

0

0

D-

9.

5.

2

0.0

1

22

5

13

1

0.0

0

2-

5

5

1

64

3

50

8

83

4

41

4

30

8

2

2

8

1

6

9

7

69

2

2

2

7

0

C

9

D-

1

5

5

7

74

5 81

7 83

8

2

6

4

0.

0.

0.

1

0

0

0

0.

4

.

0

1

0

0

5.

6.

3

0.0

1

1.

5

0.

1

0.0

0

2-

0

0

7

64

3

22

1

13

4

40

0

74

4 81

7 83

31

3

3

17

6

63

3

86

6

27

4

7

3

7

1

8

0.

0.

0.

0. 0

5

8

82

8

6

4 8

79

8

8

1 C

7

7

0

1.

0

0.

0

0.0

0

25

2

13

0

0.0

0

65

1

54

2

84

1

43

0

78

6

5

1

3

5

25

5

. D-

3

5.

2-

6.

8

5

1

1

79

1 82

0 83

9

6

6

9 9

85

8 32

6

2

6

0

1

2

1

5

1

Table 2 Major (wt. %) and trace (ppm) elements for the Neoproterozoic Kuanyu and Cida peraluminous granites in the western Yangtze Block, South China Kuanyu pluton 27°15′20″N 102°10′33″E

Cida pluton 27°10′50″N 102°5′19″E

Sa

K

K

K

K

K

K

K

K

C

C

C

C

C

C

C

C

C

C

C

C

C

mpl

Y-

Y-

Y-

Y-

Y-

Y-

Y-

Y-

D-

D-

D-

D-

D-

D-

D-

D-

D-

D-

D-

D-

D-

e

1-

1-

1-

2-

2-

2-

2-

2-

1-

1-

1-

1-

1-

2-

2-

2-

2-

2-

2-

2-

2-

1

2

3

2

3

4

5

6

1

2

4

5

6

1

2

3

4

5

6

7

8

75

73

73

74

73

75

73

74

75

75

73

73

73

.5

.1

.1

.7

.5

.1

.9

.2

.2

.4

.5

.9

.4

6

3

7

6

5

2

4

7

1

7

6

4

8

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

14

21

20

17

21

24

21

19

23

24

23

21

20

12

13

13

12

13

12

13

13

12

12

13

13

13

.3

.3

.8

.6

.2

.5

.2

.1

.4

.2

.2

.1

.3

8

7

1

4

9

3

9

4

3

8

6

9

6

1.

2.

2.

1.

2.

2.

1.

2.

2.

2.

2.

2.

1.

54

07

07

76

13

12

96

03

06

13

06

22

86

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

02

02

02

02

02

02

02

02

02

02

02

02

02

Major elements (wt.%) 7

7

7

6

7

7

6

6

SiO

4.

3.

3.

9.

1.

1.

8.

6.

2

9

3

4

6

1

4

2

8

8

0

4

2

9

4

1

8

0.

0.

0.

0.

0.

0.

0.

0.

2

2

2

5

3

3

4

5

0

0

0

7

3

7

0

4

TiO 2

Al2 O3

1

1

1

1

1

1

1

1

2.

3.

3.

4.

4.

4.

5.

5.

3

1

1

4

7

0

8

7

0

0

5

4

4

0

0

7

Fe2

2.

2.

2.

4.

2.

3.

3.

4.

O3

4

4

4

0

0

1

0

0

T

1

6

8

6

7

3

4

0

0.

0.

0.

0.

0.

0.

0.

0.

0

0

0

0

0

0

0

0

2

2

2

4

2

4

3

4

0.

0.

0.

0.

0.

0.

0.

0.

2

2

2

7

4

5

5

7

Mn O

Mg O 3

2

2

8

3

4

9

5

0.

0.

0.

1.

0.

1.

1.

1.

7

7

7

7

9

0

1

7

2

9

9

5

7

1

1

4

3.

3.

3.

2.

2.

2.

2.

2.

2

2

2

7

7

5

2

7

1

6

2

0

3

3

4

9

4.

5.

5.

4.

5.

5.

7.

5.

6

2

2

7

8

4

2

9

1

6

6

3

3

2

9

8

0.

0.

0.

0.

0.

0.

0.

0.

0

0

0

1

0

2

1

1

6

6

6

5

9

2

1

7

0.

0.

1.

0.

1.

1.

1.

0.

9

9

0

7

1

1

0

8

3

8

0

6

0

9

4

5

9

9

9

9

9

9

9

9

Ca O

Na2 O

K2 O

P2 O5

LOI

TO

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

17

22

25

19

23

23

21

19

20

22

22

21

21

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

49

57

56

50

59

28

36

39

25

26

31

28

33

3.

3.

3.

3.

3.

3.

3.

3.

2.

2.

3.

2.

3.

09

06

22

00

14

01

24

19

88

92

18

99

29

5.

6.

5.

5.

5.

5.

5.

5.

5.

5.

5.

5.

5.

46

00

99

68

84

23

54

46

32

20

58

81

66

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

02

03

03

03

04

03

03

03

03

04

03

02

03

0.

0.

0.

0.

0.

0.

1.

1.

1.

1.

1.

1.

1.

83

87

82

76

77

94

00

18

21

02

10

19

14

99

99

10

99

99

99

99

10

99

99

99

10

99

TA

9.

9.

9.

9.

9.

9.

9.

9.

.7

.5

0.

.5

.8

.7

.8

0.

.8

.8

.5

0.

.5

L

6

6

8

6

5

8

8

5

0

5

14

1

1

5

0

09

4

0

5

08

8

7

5

4

0

0

9

6

1

1.

1.

1.

1.

2.

2.

3.

2. 1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

4

6

6

7

1

1

2

1 77

96

86

89

86

74

71

71

85

78

75

94

72

4

1

3

5

4

4

5

4

7.

8.

8.

7.

8.

7.

9.

8. 8.

9.

9.

8.

8.

8.

8.

8.

8.

8.

8.

8.

8.

8

5

4

4

5

9

5

7 55

06

21

68

98

24

78

65

20

12

76

80

95

2

2

8

3

6

5

3

7

Mg

1

1

1

3

3

2

3

3

#

20

20

22

20

20

20

20

18

18

19

20

18

21

8

7

7

1

3

9

1

0

1.

1.

1.

1.

1.

1.

1.

1. 1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

0

0

0

1

1

1

1

1 04

06

08

05

06

13

11

11

14

13

12

13

10

6

5

6

3

7

8

6

1

2.

2.

3.

2.

3.

2.

2.

2.

2.

1.

1.

2.

2.

20

38

64

50

14

11

09

20

77

20

12

02

19

1.

1.

2.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

51

75

17

63

79

72

78

78

68

59

78

76

77

3.

3.

4.

3.

4.

4.

4.

4.

4.

3.

3.

3.

3.

12

57

23

52

35

35

46

06

05

61

55

72

83

4.

6.

6.

5.

6.

6.

6.

6.

6.

6.

6.

7.

5.

66

47

42

43

44

66

42

13

99

92

39

09

67

K2 O/ Na2 O K2 O+ Na2 O

A/C NK Trace element (ppm)

Li

Be

Sc

V

Cr

Co

Ni

Cu

Zn

1

1

1

4

1

2

3

4

2.

3.

2.

2.

7.

5.

7.

2.

3

1

6

4

7

2

4

4

2.

2.

2.

2.

3.

3.

2.

2.

4

9

9

1

6

4

3

0

0

7

5

5

4

8

2

7

5.

5.

5.

8.

3.

6.

6.

8.

9

9

9

3

8

6

3

1

1

3

7

6

9

0

8

3

5.

4.

4.

3

1

1

2

3

1

9

9

2.

1.

8.

3.

1.

3

5

0

0

2

4

9

4

3.

3.

7.

1

7.

1

1

1

7

7

8

5.

5

0.

2.

6.

5

5

4

7

9

3

8

8

2

1

1

1

1

1

1

1

0

8

8

8

9

6

8

6

3

6

7

1

2

9

9

1

1.

1.

4.

6.

2.

3.

4.

6.

3

4

2

0

3

4

9

1

2

3

2

5

4

2

0

2

1.

1.

1.

6.

1.

2.

6.

6.

3

8

9

7

6

3

7

0

3

4

2

0

5

7

2

8

2

2

2

5

2

4

4

5

6.

6.

6.

9.

6.

3.

2.

8.

6

4

3

1

1

8

5

7

3.

3.

3.

4.

4.

3.

4.

3.

4.

4.

4.

4.

4.

95

82

65

22

09

98

09

83

31

08

35

03

05

24

22

18

25

20

22

21

22

24

23

22

24

24

2

9

7

1

2

0

3

5

4

7

8

1

5

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

32

24

41

47

65

45

24

52

66

64

58

51

43

0.

1.

2.

0.

1.

2.

5.

13

4.

2.

2.

18

2.

86

06

04

91

64

93

37

.0

92

04

84

.1

03

15

18

17

15

19

24

21

21

22

25

24

21

21

.7

.1

.9

.4

.5

.1

.8

.1

.1

.4

.3

.6

.3

Ga

Ge

Rb

Sr

Y

Zr

Nb

Cs

Ba

La

Ce

Pr

Nd

Sm

1

2

2

2

2

2

2

2

9.

0.

0.

4.

3.

1.

1.

5.

2

3

4

5

3

5

4

0

1.

1.

1.

1.

1.

1.

1.

1.

5

6

6

8

6

9

7

9

4

8

8

1

8

6

6

6

1

2

2

2

3

3

3

3

9

1

1

6

0

0

0

0

8

8

8

8

9

5

6

5

5

5

5

1

8

9

1

1

7.

6.

6.

0

3.

6.

3

2

6

7

4

6

9

5

2

3

3

4

4

3

3

4

3

3

4.

3.

2.

1.

4.

4.

6.

6.

4

1

8

2

4

8

2

7

1

1

1

3

2

1

2

2

8

8

7

0

3

9

1

9

1

1

0

4

2

1

2

6

1

1

1

1

1

1

1

1

0.

0.

0.

9.

9.

6.

2.

8.

9

9

7

1

1

4

5

3

1.

1.

1.

7.

3.

1

7.

7.

8

9

9

2

7

0.

3

2

0

2

3

7

6

1

4

2

4

4

4

5

5

3

9

7

2

5

6

7

1

5

5

7

0

3

0

1

4

9

6

7

5

5

5

6

6

4

5

6

2.

3.

4.

7.

0.

4.

1.

8.

3

4

2

9

2

8

9

8

1

1

1

1

1

9

1

1

1

1

1

4

2

2.

0

4

6

7

8

6

8

9

7

6

1

1

1

1

1

1

1

1

3.

4.

4.

7.

5.

2.

3.

7.

8

2

5

2

1

0

0

4

4

5

5

6

5

4

4

6

9.

0.

1.

3.

2.

2.

5.

4.

1

5

3

5

3

3

5

2

1

1

1

1

9.

9.

8.

1

0.

0.

0.

1.

4

3

7

1.

14

16

17

15

17

16

17

17

16

15

16

17

17

.6

.6

.2

.7

.9

.2

.9

.8

.3

.0

.2

.0

.3

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

20

46

32

31

49

27

45

46

31

26

33

44

35

22

24

20

22

24

21

21

21

21

20

22

22

22

3

6

6

2

0

1

9

8

2

6

5

6

7

74

12

10

11

12

10

12

13

10

10

11

11

12

.9

0

8

9

5

3

6

0

3

2

9

1

8

20

22

20

16

23

17

22

19

14

13

17

17

16

.0

.1

.2

.5

.2

.9

.6

.8

.7

.6

.5

.4

.7

15

20

20

17

21

23

22

20

26

23

25

21

21

9

5

4

1

2

5

1

7

1

1

2

2

1

6.

7.

8.

7.

10

9.

8.

8.

9.

6.

9.

8.

8.

54

76

51

25

.0

50

99

10

37

93

36

19

50

0.

0.

0.

0.

0.

1.

1.

1.

1.

0.

0.

1.

1.

98

94

99

89

94

02

09

21

21

93

98

21

04

37

42

43

41

41

38

40

38

38

36

40

41

40

2

2

4

1

8

2

3

5

4

9

7

7

5

46

59

46

40

64

56

70

68

57

51

56

72

53

.3

.3

.7

.9

.5

.6

.1

.6

.6

.1

.5

.2

.1

97

12

95

83

13

11

15

14

12

10

12

16

11

.6

4

.8

.6

5

5

2

3

8

9

6

6

0

11

14

11

9.

16

14

17

16

14

12

14

17

13

.4

.8

.5

64

.1

.2

.8

.8

.5

.6

.5

.8

.3

39

50

50

34

55

48

63

57

49

42

49

60

45

.2

.7

.6

.7

.8

.4

.8

.3

.2

.9

.8

.6

.6

7.

9.

8.

6.

10

8.

10

9.

8.

7.

8.

10

7.

09

12

72

36

.0

45

.7

79

36

35

83

.1

92

1

6

7

5

7

4

4

7

0.

0.

0.

1.

0.

0.

1.

1.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

7

7

7

2

8

7

5

4

55

62

68

59

64

62

66

63

57

57

63

62

64

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

Hf

Ta

Pb

Th

7

8

8

1

8

4

2

2

8.

9.

9.

9.

7.

8.

7.

9.

8

5

6

4

4

5

6

9

5

6

2

7

0

6

0

4

1.

1.

1.

1.

1.

1.

1.

1.

3

4

4

2

0

3

1

3

1

7

7

5

5

9

0

5

7.

8.

8.

6.

6.

8.

6.

7.

1

5

5

4

0

2

4

1

7

2

4

2

2

1

4

9

1.

1.

1.

1.

1.

1.

1.

1.

3

6

6

1

1

5

2

3

0

3

3

1

8

6

7

0

3.

4.

4.

2.

3.

4.

3.

3.

4

4

4

9

5

2

7

5

1

1

3

8

1

8

1

5

0.

0.

0.

0.

0.

0.

0.

0.

4

6

6

4

5

6

5

4

6

0

0

0

2

1

3

9

2.

3.

3.

2.

3.

3.

3.

2.

6

5

4

4

3

7

3

9

5.

7.

6.

5.

7.

6.

8.

7.

6.

5.

6.

7.

5.

64

26

04

11

90

39

05

34

09

41

56

39

90

0.

0.

0.

0.

1.

0.

1.

0.

0.

0.

0.

0.

0.

77

94

80

68

02

82

02

92

72

67

82

88

74

4.

4.

4.

3.

5.

4.

5.

4.

3.

3.

4.

4.

3.

22

79

16

45

15

14

14

57

49

34

14

23

76

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

77

83

73

61

87

71

89

78

58

56

71

70

65

2.

2.

1.

1.

2.

1.

2.

2.

1.

1.

1.

1.

1.

10

10

90

57

19

82

27

00

52

47

83

78

70

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

29

26

24

20

27

23

29

25

20

19

23

22

22

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

1.

72

50

39

14

52

36

65

47

17

10

33

31

29

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

23

21

20

17

21

19

23

21

18

16

19

19

19

5.

6.

6.

5.

6.

7.

6.

6.

7.

6.

7.

6.

6.

00

17

05

15

41

03

69

26

96

96

57

45

25

0.

0.

0.

0.

1.

0.

0.

0.

0.

0.

0.

0.

0.

58

50

58

65

00

75

59

59

72

28

70

53

74

18

16

15

15

17

14

14

13

14

14

15

14

14

.5

.2

.7

.5

.3

.7

.7

.8

.0

.5

.6

.3

.9

27

40

33

30

44

35

48

43

48

35

38

55

34

.0

.7

.2

.0

.8

.6

.7

.1

.9

.2

.7

.9

.1

7

1

7

9

1

1

0

8

0.

0.

0.

0.

0.

0.

0.

0.

3

4

4

3

4

5

4

4

7

8

8

6

8

1

7

3

5.

5.

5.

8.

6.

5.

5.

8.

6

6

2

4

4

6

9

2

0

5

5

3

9

7

2

1

1.

1.

1.

1.

2.

2.

1.

1.

2

3

3

7

4

1

2

6

1

1

1

3

5

1

1

7

1

2

2

3

2

4

4

4

8.

1.

1.

3.

7.

2.

7.

1.

5

1

4

4

3

9

8

7

4

4

4

4

4

3

3

4

1.

3.

3.

2.

2.

0.

3.

3.

0

1

3

9

5

4

2

7

5.

7.

7.

5.

4.

4.

4.

4.

3.

4.

3.

3.

4.

3.

4.

3.

4.

3.

3.

4.

3.

5

2

5

8

1

8

1

3

6

8

5

1

9

7

8

9

6

9

7

7

3

8

7

7

8

8

8

8

8 79

81

81

79

81

83

82

81

84

83

83

82

81

0

9

9

5

3

1

1

4 0

2

2

7

4

4

4

8

5

3

7

2

9

U

Tzr (℃) 3

9

5

1

1

4

7

1

Eu/

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

0.

Eu*

2

2

2

3

3

2

5

4

27

23

31

32

22

26

22

23

24

27

25

22

29

(La

5

4

3

5

2

1

1

1

1

1

5

7

0

1

1

1.

6.

3

5

8. /Yb

4.

0.

1.

9.

3.

)N

1

9

2

6

0

1.

1.

1.

1.

1.

1.

1.

1.

8

6

6

7

2

4

3

6

0

2

5

3

2

8

1

1

2

2

2

3

2

2

2

3

7

19

28

24

25

30

29

30

33

35

33

30

39

29

.3

.3

.1

.6

.5

.8

.5

.6

.2

.4

.4

.5

.5

1.

2.

2.

2.

2.

2.

2.

2.

1.

2.

2.

2.

1.

64

13

00

02

27

03

09

09

99

04

08

16

96

（ Dy/ Yb) N

6

7

7

3

8

3

5

3

21

27

21

18

30

25

33

31

27

23

27

34

24

7.

6.

9.

1.

9.

0.

2.

6.

7.

6.

7.

8.

1.

9.

4.

3.

2.

6.

1.

4.

4.

4

2

7

3

1

9

3

3

98

20

20

71

26

10

84

36

08

47

73

01

94

1

5

6

2

9

2

9

9

RE E

#

Mg = molar (MgO/(MgO + TFeO)) × 100; TFeO = All Fe calculated as FeO; A/CNK = (Al 2O3)/(CaO + 1/2

K2O+Na2O) molar ratio; δEu= (Eu)N/[(Sm)N × (Gd)N]

Table 3 Whole rock Sr-Nd isotopes data for the Neoproterozoic Kuanyu and Cida peraluminous granites in the western Yangtze Block, South China

Sa

87

Sr/

mpl

8

2sm

6

Sr

e

Sr(p

Rb(p

pm)

pm)

57.6

198

106

268

108

206

103

212

143

1

Nd/

2sm

44

Nd

87

Nd(p

Sm(p

T2DM(

εN

Isr/( Sr

pm)

pm)

Ga)

d(t)

/ Sr)i

49.1

10.1

1.75

63.5

11.5

1.74

50.6

8.72

1.60

49.2

8.36

1.64

86

Kuanyu pluton KY-

0.829

0.000

1-1

926

005

KY-

0.809

0.000

2-2

826

003

0.511

0.000

983

005

0.511

0.000

908

004

0.511

0.000

984

004

0.511

0.000

943

004

-5. 1 -4. 9

0.7099 0.7217

Cida pluton CD-

0.781

0.000

1-4

161

005

CD-

0.784

0.000

2-4

435

004

87

86

Rb/ Sr and

147

144

Sm/

-2. 9 -3. 5

0.7148 0.7128

Nd ratios were calculated using Rb, Sr, Sm and Nd contents analyzed by

ICP-MS. T2DM represent the two-stage model age and were calculated using present-day ( 0.2137, (

147

Sm/

144

147

Nd)DM = 0.51315 and (

were calculated using present-day ( 143

= [(

{1+[( λt

144

Nd/

143

Nd/

(e −1)−(

Nd) sample(t)/(

144

143

143

Nd)scample−((

Nd/

144

Nd)DM]/((

Nd/

147

147

144

Sm/

Sm/

147

Nd)CHUR = 0.1967 and (

Nd)sample−(

Nd)crust−(

147

Sm/

144

Nd)DM =

Nd)crust = 0.1012. εNd(t) values 147

Sm/

Nd)CHUR(t)−1]×104, T2DM = 1/λ×

144

144

Sm

Sm/

/144

144

147

147

Sm/

Sm/

144

144

Nd)crust) ×

Nd)DM)}.

144

Nd)CHUR = 0.512638. εNd(t)

Table 4 Zircon Lu-Hf isotopic data for the Neoproterozoic Kuanyu and Cida peraluminous granites along the western margin of the Yangtze Block, South China.

Grai n spot

176

Age (Ma)

176

Yb

177

/

H

176

Lu

2SE

f

177

/

H

2SE

f

Hf

177

/

H

( 2SE

f

176

Hf

177

/

Hf

)i

fLu /Hf

εH

2

TDM1

TDM2

f(t

S

(Ma

(Ma

)

E

)

)

138

169

2

3

151

189

4

5

134

164

7

3

145

180

3

7

147

184

4

7

152

193

7

5

145

181

6

9

150

190

4

1

154

194

1

8

145

182

6

1

140

174

3

0

139

172

4

3

147

184

KY-2 0.04

KY-2 -1

840

0.05

KY-2 -2

840

840

KY-2 -4

840

840

840

-7

840

-8

840

-9

840

-10

840

-11

840

4377

0490

0637

7283

9709

9163

6102 0.03

KY-2 -12

840

KY-2

840

0.00 071 9

7

0.02

KY-2

5

6

0.02

KY-2

052

014

0.03

KY-2

0.00

4541

0.02

KY-2

3

0.00

0.03

KY-2

057

c0.0

0.03

KY-2 -6

3467

0.03

KY-2 -5

0549 0.03

KY-2 -3

3258

0.00

0977 0.03

0.00 012 5 0.00 017 9 0.00 018 7 0.00 030 9 0.00 056 9 0.00 016 8 0.00 042 0 0.00 019 3 0.00

0.00 1365 0.00 1565 0.00 1144 0.00 1285 0.00 1038 0.00 0962 0.00 0994 0.00 0865 0.00 1230 0.00 0941 0.00 0807 0.00 0951 0.00

0.00 001 9 0.00 001 4 0.00 002 7 0.00 000 4 0.00 000 3 0.00 000 6 0.00 000 5 0.00 001 0 0.00 001 6 0.00 000 9 0.00 001 5 0.00 000 7 0.00

0.28 2305 0.28 2220 0.28 2320 0.28 2251 0.28 2225 0.28 2183 0.28 2236 0.28 2196 0.28 2186 0.28 2234 0.28 2266 0.28 2279 0.28

0.00 001 7 0.00 001 2 0.00 001 4 0.00 001 4 0.00 001 4 0.00 001 1 0.00 001 8 0.00 001 5 0.00 001 6 0.00 001 4 0.00 001 6 0.00 001 3 0.00

0.282 283 0.282 195 0.282 302 0.282 230 0.282 209 0.282 168 0.282 221 0.282 182 0.282 166 0.282 219 0.282 253 0.282 263 0.282

-0 .9 6 -0 .9 5 -0 .9 7 -0 .9 6 -0 .9 7 -0 .9 7 -0 .9 7 -0 .9 7 -0 .9 6 -0 .9 7 -0 .9 8 -0 .9 7 -0

0. 51 -2. 70 1. 31 -1. 29 -1. 94 -3. 34 -1. 50 -2. 80 -3. 56 -1. 51 -0. 23 0. 02 -1.

0. 5 9 0. 4 1 0. 5 0 0. 5 1 0. 5 0 0. 4 0 0. 6 5 0. 5 1 0. 5 6 0. 5 0 0. 5 7 0. 4 5 0.

-13

4476

025

1068

2 0.04

KY-2 -14

840

0.03

KY-2 -15

840

840

840

840

840

840

840

840

840

840

840

840

4983 0.04

KY-2 -27

3304 0.03

KY-2 -26

3154 0.01

KY-2 -25

9546 0.02

KY-2 -24

7578 0.03

KY-2 -23

5141 0.03

KY-2 -22

6911 0.03

KY-2 -21

0377 0.02

KY-2 -20

1873 0.02

KY-2 -19

8538 0.03

KY-2 -18

0447 0.07

KY-2 -17

0038 0.03

KY-2 -16

3320

840

7581

0.00 120 0 0.00 017 4 0.00 043 2 0.00 038 8 0.00 009 3 0.00 005 9 0.00 002 6 0.00 015 6 0.00 018 9 0.00 044 1 0.00 058 0 0.00 019 1 0.00 012 8 0.00 147 0

000

2226

9 0.00 1344 0.00 0937 0.00 0939 0.00 2468 0.00 1008 0.00 0625 0.00 0859 0.00 1117 0.00 1149 0.00 1270 0.00 0693 0.00 0387 0.00 1112 0.00 1458

0.00 003 7 0.00 000 5 0.00 001 2 0.00 001 0 0.00 000 2 0.00 000 3 0.00 000 1 0.00 000 6 0.00 000 7 0.00 001 2 0.00 001 7 0.00 000 7 0.00 000 7 0.00 004 2

001

209

5 0.28 2215 0.28 2221 0.28 2235 0.28 2243 0.28 2206 0.28 2283 0.28 2275 0.28 2200 0.28 2261 0.28 2229 0.28 2224 0.28 2209 0.28 2064 0.28 2248

0.00 001 5 0.00 001 3 0.00 001 2 0.00 001 4 0.00 001 4 0.00 001 2 0.00 001 3 0.00 001 5 0.00 001 6 0.00 001 5 0.00 001 5 0.00 001 2 0.00 001 4 0.00 001 2

.9

98

7 0.282 194 0.282 206 0.282 220 0.282 204 0.282 190 0.282 273 0.282 261 0.282 182 0.282 243 0.282 209 0.282 213 0.282 202 0.282 047 0.282 225

-0 .9 6 -0 .9 7 -0 .9 7 -0 .9 3 -0 .9 7 -0 .9 8 -0 .9 7 -0 .9 7 -0 .9 7 -0 .9 6 -0 .9 8 -0 .9 9 -0 .9 7 -0 .9 6

5

5

9

150

189

7

1

147

185

4

0

145

181

5

9

153

190

8

7

149

188

9

8

136

169

9

1

139

172

4

5

151

191

4

0

143

177

1

6

148

185

3

5

145

182

5

4

145

183

8

8

170

221

3

0

146

182

8

5

2 -2. 63 -1. 98 -1. 50 -2. 90 -2. 61 0. 54 0. 00 -2. 95 -0. 81 -2. 07 -1. 55 -1. 80 -7. 75 -1. 58

0. 5 4 0. 4 6 0. 4 1 0. 5 0 0. 4 9 0. 4 1 0. 4 6 0. 5 2 0. 5 5 0. 5 1 0. 5 3 0. 4 2 0. 5 1 0. 4 2

0.05

KY-2 -28

840

0.04

KY-2 -29

840

840

840

840

4935 0.03

KY-2 -33

5763 0.03

KY-2 -32

0099 0.02

KY-2 -31

3175 0.07

KY-2 -30

1591

840

7344

0.00 126 0 0.00 013 8 0.00 120 0 0.00 013 3 0.00 027 1 0.00 006 7

0.00 1583 0.00 1319 0.00 2202 0.00 0781 0.00 1098 0.00 1156

0.00 003 3 0.00 000 3 0.00 004 1 0.00 000 5 0.00 000 9 0.00 000 1

0.28 2232 0.28 2295 0.28 2249 0.28 2246 0.28 2286 0.28 2232

0.00 001 4 0.00 001 4 0.00 001 3 0.00 001 4 0.00 001 7 0.00 001 5

0.282 207 0.282 274 0.282 214 0.282 234 0.282 268 0.282 214

-0 .9 5 -0 .9 6 -0 .9 3 -0 .9 8 -0 .9 7 -0 .9 7

-2. 31 0. 20 -2. 43 -0. 95 0. 13 -1. 81

0. 5 0 0. 4 9 0. 4 6 0. 5 1 0. 6 1 0. 5 3

149

187

8

0

139

171

4

3

151

187

3

7

142

178

9

4

139

171

3

7

147

184

1

0

146

182

5

6

135

166

2

2

136

168

5

1

137

168

4

5

135

164

2

8

139

172

2

4

126

151

9

9

137

169

8

1

134

164

CD-1 CD1-01 CD1-02 CD1-03 CD1-04 CD1-05 CD1-06 CD1-07 CD1-08 CD-

835

835

835

835

835

835

835

835 835

0.04 4827 0.02 3330 0.02 5763 0.04 3642 0.04 6547 0.02 8904 0.04 1728 0.04 5957 0.03

0.00 005 9 0.00 023 6 0.00 025 4 0.00 010 8 0.00 032 2 0.00 016 0 0.00 012 2 0.00 006 7 0.00

0.00 1387 0.00 0761 0.00 0817 0.00 1334 0.00 1444 0.00 0912 0.00 1338 0.00 1370 0.00

0.00 000 5 0.00 000 6 0.00 000 6 0.00 000 4 0.00 000 7 0.00 000 4 0.00 000 5 0.00 000 4 0.00

0.28 2247 0.28 2301 0.28 2294 0.28 2309 0.28 2329 0.28 2278 0.28 2384 0.28 2307 0.28

0.00 003 0 0.00 002 3 0.00 002 2 0.00 002 8 0.00 002 4 0.00 002 3 0.00 001 9 0.00 002 2 0.00

0.282 225 0.282 289 0.282 281 0.282 288 0.282 306 0.282 264 0.282 362 0.282 286 0.282

-0 .9 6 -0 .9 8 -0 .9 8 -0 .9 6 -0 .9 6 -0 .9 7 -0 .9 6 -0 .9 6 -0

-1. 64 0. 97 0. 65 0. 57 1. 18 -0. 05 3. 21 0. 49 1.

1. 0 6 0. 8 0 0. 7 7 0. 9 9 0. 8 5 0. 8 0 0. 6 6 0. 7 8 0.

1-09

6242

006

1127

8 CD1-10 CD1-11 CD1-12 CD1-13 CD1-14 CD1-15 CD1-16 CD1-17 CD1-18 CD1-19 CD1-20 CD1-21 CD1-22 CD1-23

835

835

835

835

835

835

835

835

835

835

835

835

835

835

0.03 7529 0.05 1225 0.03 0516 0.07 6121 0.03 9162 0.03 1628 0.05 2256 0.03 9020 0.03 1997 0.03 2707 0.04 1519 0.04 1500 0.03 5231 0.04 4314

0.00 061 4 0.00 022 5 0.00 016 5 0.00 022 1 0.00 010 5 0.00 004 3 0.00 046 3 0.00 028 1 0.00 011 9 0.00 034 9 0.00 029 2 0.00 017 2 0.00 007 3 0.00 019 2

000

2323

2 0.00 1150 0.00 1546 0.00 0930 0.00 2319 0.00 1181 0.00 1086 0.00 1729 0.00 1197 0.00 0995 0.00 1028 0.00 1281 0.00 1283 0.00 1078 0.00 1368

0.00 001 7 0.00 000 5 0.00 000 5 0.00 000 9 0.00 000 2 0.00 000 4 0.00 001 1 0.00 000 7 0.00 000 5 0.00 001 1 0.00 000 8 0.00 000 5 0.00 000 3 0.00 000 6

002

305

2 0.28 2273 0.28 2294 0.28 2253 0.28 2312 0.28 2279 0.28 2264 0.28 2201 0.28 2288 0.28 2334 0.28 2230 0.28 2237 0.28 2204 0.28 2196 0.28 2312

0.00 002 1 0.00 002 2 0.00 002 6 0.00 002 4 0.00 001 4 0.00 002 8 0.00 004 3 0.00 002 1 0.00 001 8 0.00 002 0 0.00 002 4 0.00 002 9 0.00 002 2 0.00 002 3

.9

31

7 0.282 255 0.282 270 0.282 238 0.282 275 0.282 260 0.282 247 0.282 174 0.282 269 0.282 318 0.282 213 0.282 217 0.282 184 0.282 179 0.282 290

-0 .9 7 -0 .9 5 -0 .9 7 -0 .9 3 -0 .9 6 -0 .9 7 -0 .9 5 -0 .9 6 -0 .9 7 -0 .9 7 -0 .9 6 -0 .9 6 -0 .9 7 -0 .9 6

7

3

0

141

175

3

1

140

173

7

2

142

178

8

1

143

174

0

7

140

174

7

0

142

176

2

6

155

195

1

3

139

172

6

3

131

160

9

6

146

184

7

0

147

184

2

0

151

191

9

5

151

191

8

9

137

168

2

1

8 -0. 47 -0. 18 -0. 96 -0. 39 -0. 28 -0. 71 -3. 71 -0. 02 1. 83 -1. 92 -1. 89 -3. 11 -3. 16 0. 63

0. 7 4 0. 7 9 0. 9 0 0. 8 6 0. 5 1 1. 0 0 1. 5 4 0. 7 3 0. 6 2 0. 7 2 0. 8 6 1. 0 4 0. 7 8 0. 8 0

CD1-24 CD1-25 CD1-26 CD1-27 CD1-28

835

835

835

835

835

0.04 8728 0.04 2244 0.04 3384 0.03 3887 0.03 6010

0.00 017 7 0.00 045 5 0.00 049 6 0.00 019 3 0.00 009 6

0.00 1487 0.00 1372 0.00 1298 0.00 1061 0.00 1105

0.00 000 5 0.00 001 3 0.00 001 5 0.00 000 6 0.00 000 3

0.28 2351 0.28 2350 0.28 2244 0.28 2311 0.28 2243

0.00 002 7 0.00 001 6 0.00 002 9 0.00 002 5 0.00 001 7

0.282 327 0.282 329 0.282 224 0.282 295 0.282 226

-0 .9 6 -0 .9 6 -0 .9 6 -0 .9 7 -0 .9 7

1. 86 1. 99 -1. 66 0. 96 -1. 49

0. 9 5 0. 5 6 1. 0 2 0. 8 7 0. 6 1

132

160

4

3

131

159

8

6

146

182

3

6

135

166

5

1

145

181

3

5

142

176

8

7

143

174

0

0

133

162

0

3

138

169

0

8

138

170

8

9

127

153

7

0

145

181

9

5

132

160

3

1

142

178

9

3

128

154

CD-2 CD2-01 CD2-02 CD2-03 CD2-04 CD2-05 CD2-06 CD2-07 CD2-08 CD2-09 CD-

835

835

835

835

835

835

835

835

835 835

0.04 7357 0.08 5741 0.02 8067 0.04 0418 0.04 1037 0.04 0791 0.05 0442 0.04 5227 0.02 8394 0.04

0.00 057 4 0.00 033 4 0.00 017 0 0.00 023 9 0.00 027 0 0.00 049 6 0.00 039 1 0.00 060 0 0.00 009 5 0.00

0.00 1434 0.00 2599 0.00 0961 0.00 1249 0.00 1269 0.00 1347 0.00 1493 0.00 1505 0.00 0904 0.00

0.00 001 5 0.00 001 1 0.00 000 4 0.00 000 8 0.00 000 7 0.00 001 7 0.00 000 9 0.00 002 0 0.00 000 3 0.00

0.28 2275 0.28 2323 0.28 2325 0.28 2301 0.28 2296 0.28 2378 0.28 2256 0.28 2352 0.28 2251 0.28

0.00 002 0 0.00 002 9 0.00 001 5 0.00 001 4 0.00 001 4 0.00 001 8 0.00 001 7 0.00 001 7 0.00 001 5 0.00

0.282 253 0.282 282 0.282 310 0.282 281 0.282 276 0.282 357 0.282 232 0.282 328 0.282 237 0.282

-0 .9 6 -0 .9 2 -0 .9 7 -0 .9 6 -0 .9 6 -0 .9 6 -0 .9 6 -0 .9 5 -0 .9 7 -0

-0. 72 -0. 29 1. 59 0. 33 0. 18 3. 06 -1. 52 1. 93 -1. 01 2.

0. 7 2 1. 0 2 0. 5 5 0. 5 0 0. 5 1 0. 6 3 0. 6 1 0. 6 1 0. 5 3 0.

2-10

4653

021

1547

6 CD2-11 CD2-12 CD2-13 CD2-14 CD2-15 CD2-16 CD2-17 CD2-18

835

835

835

835

835

835

835

835

0.04 1337 0.02 9799 0.02 9876 0.05 3500 0.03 8353 0.04 2838 0.04 3756 0.06 3272

0.00 031 4 0.00 025 3 0.00 008 0 0.00 037 9 0.00 022 1 0.00 013 3 0.00 013 0 0.00 014 0

000

2378

7 0.00 1251 0.00 0939 0.00 0922 0.00 1675 0.00 1181 0.00 1420 0.00 1347 0.00 1912

0.00 000 8 0.00 000 6 0.00 000 2 0.00 001 4 0.00 000 6 0.00 000 4 0.00 000 4 0.00 000 4

002

353

0 0.28 2297 0.28 2374 0.28 2277 0.28 2262 0.28 2266 0.28 2252 0.28 2288 0.28 2251

0.00 001 9 0.00 001 5 0.00 001 5 0.00 001 9 0.00 001 6 0.00 002 1 0.00 001 6 0.00 001 8

.9

75

5 0.282 277 0.282 360 0.282 263 0.282 236 0.282 247 0.282 230 0.282 267 0.282 221

-0 .9 6 -0 .9 7 -0 .9 7 -0 .9 5 -0 .9 6 -0 .9 6 -0 .9 6 -0 .9 4

7

9

7

138

170

6

6

125

151

9

2

139

172

4

5

146

181

0

2

142

177

5

0

145

181

9

7

140

173

5

4

149

185

1

4

2 0. 22 3. 31 -0. 05 -1. 46 -0. 78 -1. 54 -0. 22 -2. 15

0. 6 7 0. 5 2 0. 5 3 0. 6 7 0. 5 7 0. 7 5 0. 5 7 0. 6 4

Highlights  The peraluminous granites in the western margin of the Yangtze Block were formed at ca. 840-835 Ma  They

were

mainly

formed

by

disequilibrium

partial

melting

of

heterogeneous metasedimentary sources.  They represent the melting of mature continental crust under the early stage of Neoproterozoic subduction process