Magma Recharge and Reactive Bulk Assimilation in Enclave-Bearing Granitoids, Tonglu, South China

Magma Recharge and Reactive Bulk Assimilation in Enclave-Bearing Granitoids, Tonglu, South China ABSTRACT Magmatic processes leading to granitoid formation are of relevance to the evolution of continental crust and its mineralization. A comprehensive study of field observations with whole-rock and in situ mineral chemical and isotopic compositions was carried out on granitoids, mafic microgranular enclaves (MME) and country-rock xenoliths (CRX) from Tonglu, South China to constrain the magmatic processes operating. Zircon U–Pb geochronology indicates that the MME and granitoids formed coevally at ∼130 Ma. Petrographic observations suggest that the MME are quenched mafic clots formed during incomplete magma mixing. The different zircon Hf isotopic compositions of the MME (εHf(t) = -4·0 to -0·7) and the host granitoids (εHf(t) = -8·1 to -1·7) indicate mingling between mafic and felsic magmas from different sources. The CRX are composed of fresh cores and dark rims. The pyroxene-rich fresh cores are depleted in Rb, Ba and K while the biotite-rich dark rims show obvious enrichments in Rb, Ba and K, indicating modification by hydrous K-rich felsic melts or fluids from the host magma. In contrast, some large CRX have embayed structures and are surrounded by several small, biotite-rich CRX, suggesting disaggregation and modification of large CRX into the host magma. The occurrence of abundant felsic magmatic veinlets in the CRX implies that they could have experienced brittle deformation in the cold shallow crust, which agrees with an emplacement depth of about 5 km estimated using Al-in hornblende geobarometry. The high 87Sr/86Sri (0·7129) and low εNd(t) (-10·2) values imply that these CRX were derived from the upper continental crust. All these features suggest a typical reactive bulk assimilation process. Microanalysis of 87Sr/86Sr ratios in plagioclase from the Tonglu granitoids vary over a large range (0·7073–0·7137) with complex rim-core-rim variations, which resulted from open-system processes. Given the variation in Sr isotopes, four types of plagioclase were identified. Type I plagioclase are homogeneous in terms of 87Sr/86Sr, suggesting normal crystal fractionation. Recharge of mafic magma injecting into felsic magma resulted in the core–mantle variations of type II plagioclases. Albitic cores with high 87Sr/86Sr (up to 0·7092) indicate felsic magma with highly radiogenic Sr (87Sr/86Sr > 0·7092). Influx of mafic magma with less radiogenic Sr (87Sr/86Sr < 0·7080) resulted in a decrease in 87Sr/86Sr and an abrupt increase of An contents (∼An30 to ∼An60) from core to mantle. Type III plagioclase are distinguished by lower 87Sr/86Sr ratios in the core (0·7084–0·.7086) and significantly more radiogenic Sr at the rim (0·7097–0·7112), which is attributed to the assimilation of the country rocks. Core-mantle-rim variations in type IV plagioclase not only record magma recharge events, but also crustal assimilation. Increasing An values and decreasing 87Sr/86Sr ratios (down to 0·7075) from core to mantle and significantly more radiogenic Sr (up to 0·7117) in the outer rim suggest that the recharge event took place prior to the assimilation of ancient crustal components. Recharge of hot mafic magma into a pre-existing magma chamber will not only increase the temperature of the magma in the chamber, but may also induce intense shattering of the brittle country-rocks, both of which could have enhanced the process of reactive bulk assimilation. INTRODUCTION Granitoids are the defining components of the Earth’s felsic continental crust relative to other terrestrial planets (Campbell & Taylor, 1983; Kemp & Hawkesworth, 2003; Kemp et al., 2007). The petrogenesis of such granitoids is of relevance to the evolution of the continental crust (Allègre & Othman, 1980; Kemp & Hawkesworth, 2003; Hawkesworth & Kemp, 2006) and the formation of economically significant mineral resources such as W, Sn, Au Cu, Pb, Zn (Mao et al., 2008; Xie et al., 2013; Delibaş et al., 2016). A long-standing debate regarding the magmatic processes leading to granitoid formation is whether they occur in open- or closed-systems. Hybridization of granitoids via open-system processes including magma recharge and crustal assimilation are common in felsic magma chambers. They can affect the composition, temperature and oxygen fugacity of the magma system, thus affecting the distribution of trace elements. Various models (e.g. recharge, assimilation and fractional crystallization (RAFC) model) have been proposed to quantify the hybridization of magmas (DePaolo, 1981; Spera & Bohrson, 2001, 2004). It is essential to trace not only the processes in the source region, but also the interaction of pre-existing magma with recharge magma and the country rocks at the emplacement depth (Saito et al., 2007; Zhang et al., 2016; Fisher et al., 2017). These hybrid processes leave geochemical and mineralogical fingerprints in an evolving magma (Saito et al., 2007; Ginibre & Davidson, 2014; Zhang et al., 2016). These processes are recorded in detail by chemical and isotopic heterogeneities at grain- and sometimes sub-grain scales (Tepley et al., 2000; Sun et al., 2010) which can be revealed by spatially controlled micro-analyses, using either laser ablation methods or micro-drilling followed by conventional analysis (Davidson et al., 2001; Griffin et al., 2002; Fisher et al., 2017). Combination of in situ isotopic and element data with petrographic observations afford a deeper insight into the nature of magma sources and magma generation processes (Davidson & Tepley, 1997; Tepley et al., 2000; Davidson et al., 2001; Griffin et al., 2002; Gagnevin et al., 2005; Yang et al., 2007b; Alves et al., 2009; Zhang et al., 2015) compared to classic geochemical or isotopic studies performed at whole-rock scale. In situ Sr isotope analysis of plagioclase is a useful tool for unraveling the origin and evolution of magmas (Tepley & Davidson, 2003; Davidson et al., 2007; Pietranik & Waight, 2008; Alves et al., 2009). Plagioclase is a common mineral in mafic to felsic magmas, and the slow CaAl–NaSi diffusion allows plagioclase zoning to be well preserved (Grove et al., 1984; Berlo et al., 2007; Shcherbakov et al., 2011). Therefore, using a combination of morphological, chemical and Sr isotopic characteristics of plagioclase can record the complete processes of long-lived magma evolution (Gagnevin et al., 2005; Davidson et al., 2007; Ginibre & Davidson, 2014). In this study, we combine field observations with whole-rock and in situ mineral chemical and isotopic compositions to constrain in detail the hybridization processes operating in enclave-bearing granitoids from Tonglu, South China. In particular, we show that the elemental and Sr isotopic zonation of plagioclases can effectively trace the characteristics of the primitive magma end-members and highlight any reactive bulk assimilation. GEOLOGICAL BACKGROUND The South China Block (SCB) is a segment within the eastern margin of Eurasia and was the upper plate during the westward Andean-style subduction of the Paleo-Pacific plate during the late Mesozoic. The history of this continental upper plate is complex. It comprises the Yangtze Block in the northwest and the Cathaysia Block in the southeast (Fig. 1), separated by the deep-seated Jiangshan–Shaoxing Fault Zone (Fig. 1). The Yangtze and Cathaysia Blocks have distinctive crustal ages and tectonic histories (Qiu et al., 2000). They were thought to have been amalgamated at c. 1·1–0·9 Ga (Chen & Jahn, 1998; Ye et al., 2007) or c. 0·87–0·82 Ga (Wang et al., 2006) associated with the formation of the supercontinent Rodinia. The basement rocks of the Yangtze Block, ranging from Archean to Proterozoic, are mainly exposed in the western regions of block, such as the Kongling, Kangding and Dahongshan areas (Qiu et al., 2000). However, the Precambrian rocks within the Cathaysia Block mostly give Proterozoic ages; no Archean basement has yet been reported (Chen & Jahn, 1998). The subduction of the Paleo-Pacific plate under the SCB resulted in large-scale magmatism during the Cretaceous (Chen et al., 2000; Zhou & Li, 2000; Li & Li, 2007; Wong et al., 2011). Amounts of A-type granite and mafic rocks have been discovered in the Ganzhou–Hangzhou belt (include South Anhui, West Zhejiang and East Jiangxi) (Fig. 1b), suggesting an extensional setting in the Early Cretaceous (125–135 Ma) (Yu et al., 2004; Wong et al., 2009; Jiang et al., 2011; Yang et al., 2011, 2012). Fig. 1. View largeDownload slide (a) The location of the South China Block; (b) Simplified geological map of South China showing the distribution of Mesozoic granitoids and volcanic rocks (modified after Zhou et al. (2006) and Yang et al. (2012)); (c) Simplified geological map of the Tonglu granitoids (modified after the Geological map of Jiande sheet 1: 200 000). Fig. 1. View largeDownload slide (a) The location of the South China Block; (b) Simplified geological map of South China showing the distribution of Mesozoic granitoids and volcanic rocks (modified after Zhou et al. (2006) and Yang et al. (2012)); (c) Simplified geological map of the Tonglu granitoids (modified after the Geological map of Jiande sheet 1: 200 000). The Tonglu volcanic-intrusive complex was emplaced in the Ganzhou–Hangzhou belt (West Zhejiang) (Fig. 1b) between 130–135 Ma (Chen et al., 1999; Wong et al., 2011) and corresponded to a period of extension. The Tonglu Basin is a volcanic collapse basin, covering an area of about 460 km2, exposed as an ellipsoidal shaped body trending in a NE–SW direction (Fig. 1c). The complex contains a large section of rhyolitic lavas, overlain by a thick section of rhyodacite. It was intruded by monzodiorite, quartz monzonite and monzonite containing mafic microgranular enclaves (MME) and country-rock xenoliths (CRX). No age information exists for the monzodiorites and MME. SAMPLES AND PETROGRAPHY The Tonglu intrusive suite comprises monzodiorites, monzonites and quartz monzonites, which are well exposed in three active quarries. Forty-five samples were collected from E’shan, Zhongshan and Shixia on the southwest of the intrusion (Fig. 1c). The intrusion in E’shan is monzonite, in which abundant MME were found (Fig. 2a and b). The host monzonite sampled for analysis is from the inner monzonite close to the boundary of an MME, aiming to trace the effect of mixing or mingling on the composition of the host-rocks. The samples collected from Shixia are monzodiorite, in which no MME and CRX were found. The intrusions in Zhongshan are of monzodiorite and quartz monzonite. The quartz monzonites contain some MME and CRX, but these are absent in the monzodiorites. Samples were collected from the inner quartz monzonites and the boundary of CRX and quartz monzonite, aiming to constrain the effect of crustal assimilation on the composition of the host-rock. A summary of the petrographic features of the samples is listed in Table 1. All the samples have similar mineral assemblages (plagioclase, K-feldspar, quartz, amphibole and biotite) but in different mineral proportions. Quartz content increases from the monzodiorite to quartz monzonite, whereas mafic minerals decrease. Amphibole and biotite are common in all samples. Accessory minerals are mainly zircon, apatite, titanite and magnetite. Table 1: Petrographic features of the Tonglu granitoids Rock type Occurrence Characteristic texture Rock-forming minerals Accessory minerals Monzodiorite Outer parts of the intrusion without MME Medium grained, granogranulitic texture Plagioclase (40%), K-feldspar (25%), amphibole (20%), biotite (10%), quartz (5%) Zircon, apatite, magnetite Monzonite Dominant type with abundant MME Fine to medium grained, granogranulitic texture, micrographic texture of K-feldspar and quartz Plagioclase (40%), K-feldspar (35%), quartz (10%), biotite (10%), amphibole (5%) Zircon, apatite, magnetite Quartz monzonite Outer parts of the intrusion with a few MME and CRX Fine grained, equigranular to porphyritic texture Plagioclase (35%), quartz (20%) K-feldspar (35%), biotite (5%), amphibole (4%), pyroxene (1%) Zircon, apatite, magnetite Rock type Occurrence Characteristic texture Rock-forming minerals Accessory minerals Monzodiorite Outer parts of the intrusion without MME Medium grained, granogranulitic texture Plagioclase (40%), K-feldspar (25%), amphibole (20%), biotite (10%), quartz (5%) Zircon, apatite, magnetite Monzonite Dominant type with abundant MME Fine to medium grained, granogranulitic texture, micrographic texture of K-feldspar and quartz Plagioclase (40%), K-feldspar (35%), quartz (10%), biotite (10%), amphibole (5%) Zircon, apatite, magnetite Quartz monzonite Outer parts of the intrusion with a few MME and CRX Fine grained, equigranular to porphyritic texture Plagioclase (35%), quartz (20%) K-feldspar (35%), biotite (5%), amphibole (4%), pyroxene (1%) Zircon, apatite, magnetite Table 1: Petrographic features of the Tonglu granitoids Rock type Occurrence Characteristic texture Rock-forming minerals Accessory minerals Monzodiorite Outer parts of the intrusion without MME Medium grained, granogranulitic texture Plagioclase (40%), K-feldspar (25%), amphibole (20%), biotite (10%), quartz (5%) Zircon, apatite, magnetite Monzonite Dominant type with abundant MME Fine to medium grained, granogranulitic texture, micrographic texture of K-feldspar and quartz Plagioclase (40%), K-feldspar (35%), quartz (10%), biotite (10%), amphibole (5%) Zircon, apatite, magnetite Quartz monzonite Outer parts of the intrusion with a few MME and CRX Fine grained, equigranular to porphyritic texture Plagioclase (35%), quartz (20%) K-feldspar (35%), biotite (5%), amphibole (4%), pyroxene (1%) Zircon, apatite, magnetite Rock type Occurrence Characteristic texture Rock-forming minerals Accessory minerals Monzodiorite Outer parts of the intrusion without MME Medium grained, granogranulitic texture Plagioclase (40%), K-feldspar (25%), amphibole (20%), biotite (10%), quartz (5%) Zircon, apatite, magnetite Monzonite Dominant type with abundant MME Fine to medium grained, granogranulitic texture, micrographic texture of K-feldspar and quartz Plagioclase (40%), K-feldspar (35%), quartz (10%), biotite (10%), amphibole (5%) Zircon, apatite, magnetite Quartz monzonite Outer parts of the intrusion with a few MME and CRX Fine grained, equigranular to porphyritic texture Plagioclase (35%), quartz (20%) K-feldspar (35%), biotite (5%), amphibole (4%), pyroxene (1%) Zircon, apatite, magnetite Fig. 2. View largeDownload slide Field photographs and photomicrographs showing typical structures and textures of the Tonglu granitoids and MME. (a) stretched MME; (b) abundant MME with spheroidal to ellipsoidal shapes; (c) amphibole in the monzodiorite; (d) plagioclase in quartz monzonite exhibiting complex oscillatory zoning; (e) Micrographic texture of K-feldspar and quartz in the host monzonite; (f) acicular apatite in MME; (g) plagioclase phenocryst in MME; and (h) fine-grained quenched margin between MME and host rock. Kf: K-feldspar; Pl: plagioclase; Bt: biotite; Ap: apatite; Q: quartz. Fig. 2. View largeDownload slide Field photographs and photomicrographs showing typical structures and textures of the Tonglu granitoids and MME. (a) stretched MME; (b) abundant MME with spheroidal to ellipsoidal shapes; (c) amphibole in the monzodiorite; (d) plagioclase in quartz monzonite exhibiting complex oscillatory zoning; (e) Micrographic texture of K-feldspar and quartz in the host monzonite; (f) acicular apatite in MME; (g) plagioclase phenocryst in MME; and (h) fine-grained quenched margin between MME and host rock. Kf: K-feldspar; Pl: plagioclase; Bt: biotite; Ap: apatite; Q: quartz. The MME have spheroidal to ellipsoidal shapes, with sizes ranging from a few centimetres to a metre in the longest dimension, some of which are stretched with large length/width ratios (Fig. 2a and b). They show fine-grained microgranular textures. MME have similar mineralogical characteristics to their host-rocks, but smaller grains than those of the host monzonite (Fig. 2h). Compared to the host monzonites, MME contain more mafic minerals and plagioclase. Acicular apatites are widely found in the MME (Fig. 2f). In contrast, rare CRX (a few decimetres in diameter) were also found in the Tonglu granitoids (Fig. 3a and c). They show different petrological features from the host granitoids (Fig. 3a–d), with fresh green cores and dark rims (Fig. 3a, c and d). The green cores are diopside halleflinta containing quartz, plagioclase, pyroxene and secondary minerals such as chlorite, lacking any high pressure metamorphic minerals and structures, and showing distinctive features similar to the basement of this area (e.g. amphibolite, gneiss and granulite) (Zheng & Zhang, 2007). The dark rims contain more biotite and less pyroxene. Some CRX have an embayed erosional structure (Fig. 3a) and crosscutting felsic magmatic veinlets. Some minerals in the host rock-CRX boundary have been disaggregated and distributed into the host rocks. Fig. 3. View largeDownload slide Field photographs and photomicrographs of the CRX and host granitoids. (a) large CRX has an embayed erosional structure and is surrounded by several small biotite-rich CRX; (b) felsic magmatic veinlets in the CRX; (c) CRX and its dark rim (d) Host-rock, CRX and dark rim in thin section; (e) CRX with abundant clinopyroxene; (f) dark rim with abundant biotite. Bt: biotite; Py: pyroxene; Pl: plagioclase; Q: quartz. Fig. 3. View largeDownload slide Field photographs and photomicrographs of the CRX and host granitoids. (a) large CRX has an embayed erosional structure and is surrounded by several small biotite-rich CRX; (b) felsic magmatic veinlets in the CRX; (c) CRX and its dark rim (d) Host-rock, CRX and dark rim in thin section; (e) CRX with abundant clinopyroxene; (f) dark rim with abundant biotite. Bt: biotite; Py: pyroxene; Pl: plagioclase; Q: quartz. ANALYTICAL METHODS Major and trace elements Bulk-rock major and trace element compositions Whole-rock samples were crushed in a corundum jaw crusher down to 60 mesh size. Approximately 50 g was powdered in an agate ring mill to less than 200 mesh size. The major elements were analysed using a X-ray fluorescence (Shimadzu XRF-1800) at the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan (GPMR-CUG). The analytical precision and accuracy for major elements were better than 5%. The sample preparation and analytical procedures were described in detail by Su et al. (2012). Trace elements were analysed using an Agilent 7700x ICP-MS at GPMR. Approximately 50 mg of each sample was digested in HF + HNO3 in Teflon bombs for ICP-MS analysis. The sample-digesting procedure for ICP-MS analysis and the analytical precision and accuracy for trace elements were the same as those described by Liu et al. (2008b). Mineral major and trace element analyses The major and trace element compositions of minerals were measured using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) at GPMR-CUG. The operating conditions for LA-ICP-MS are the same as those described by Liu et al. (2008a). Laser sampling was conducted using a 193 nm ArF excimer laser ablation system (GeoLas 2005, Lambda Physik Göttingen, Germany) with a spot size of 44 μm. An Agilent 7500a ICP-MS instrument was used to acquire ion-signal intensities. NIST 610 was analysed every 6 analyses to correct the time-dependent drift of sensitivity and mass discrimination for the element analysis. The element compositions were calibrated against multiple reference materials (BHVO-2G, BCR-2G and BIR-1G) (Liu et al., 2008a). Offline selection and integration of background and analytical signals and time-drift correction and quantitative calibration were conducted using ICPMSDataCal (Liu et al., 2008a; Lin et al., 2016). The detailed calibration strategy for accurate LA-ICP-MS analysis of major and trace elements in hydrous silicate minerals was reported in Chen et al. (2014) Zircon U–Pb dating and Hf isotopic analyses Zircons were separated by a conventional mineral separation technique. They were then mounted in epoxy resin and polished. Finally, the zircons were cleaned in a 5% HNO3 bath with an ultrasonic washer prior to analysis. U–Pb dating and trace element analyses of zircons were performed simultaneously by LA-ICP-MS at GPMR-CUG. The operating conditions for the laser ablation system and the quadrupole ICP-MS instrument were the same as those described by (Liu et al., 2010b). Laser sampling was conducted using a GeoLas 2005 laser ablation system with a spot size of 32 μm. An Agilent 7500a ICP-MS instrument was used to acquire ion-signal intensities. Zircon standard 91500 was used as an external standard to calibrate isotope fractionation; this was analysed twice for every six analyses. NIST 610 was analysed to correct the time-dependent drift of sensitivity and mass discrimination for the trace element analyses. Offline selection and integration of background and analytical signals and time-drift correction and quantitative calibration were conducted using ICPMSDataCal (Liu et al., 2010b). The obtained Concordia age of zircon standard GJ-1 (603·8 ± 4·1Ma, 2σ, n = 16) agrees well with the preferred ID-TIMS 206Pb/238U age within analytical uncertainty (599·8 ± 4·8 Ma (2σ); Jackson et al., 2004). Zircon Hf isotopic analyses were conducted using a Neptune Plus MC-ICP-MS (Thermo Fisher Scientific, Germany) and a GeoLas 2005 laser ablation system at GPMR-CUG. All data were acquired in the single-spot ablation mode using a spot size of 44 μm. The operating conditions for the laser ablation system and the MC-ICP-MS instrument and the analytical methods are the same as those described in detail by Hu et al. (2010). Off-line selection and integration of analyte signals and mass bias calibrations were performed using ICPMSDataCal (Liu et al., 2010a; Lin et al., 2016). The obtained zircon Hf isotopic compositions of the standards GJ-1 (0·282013 ± 0·000006 (2σ, n = 8)), Temora-2 (0·282679 ± 0·000008 (2σ, n = 8)) and 91500 (0·282308 ± 0·000005 (2σ, n = 19)) agree well with reference values within analytical uncertainty (Woodhead & Hergt, 2005; Blichert-Toft, 2008; Morel et al., 2008). Sr–Nd isotopic analyses Whole-rock Sr–Nd isotopic analyses Whole-rock Sr–Nd isotopic compositions were analysed using a Triton TI TIMS (Thermo Finnigan, Germany) operated in static mode at GPMR-CUG. The measured Sr–Nd isotopic compositions of standards GSP-2 (87Sr/86Sr = 0·765119 ± 0·000012 (2SE); 143Nd/144Nd = 0·511367 ± 0·000010 (2SE)), AGV-2 (87Sr/86Sr = 0·704000 ± 0·000014 (2SE); 143Nd/144Nd = 0·512783 ± 0·000008 (2SE)) and BHVO-2 (87Sr/86Sr = 0·703476 ± 0·000012 (2SE); 143Nd/144Nd = 0·512972 ± 0·000008 (2SE)) agree well with reference values within analytical uncertainty (Raczek et al., 2003). Details of the Sr–Nd isotopic analysis procedures were reported in Gao et al. (2004). In situ Sr isotopic analysis of plagioclase In situ Sr isotope compositions of plagioclase were determined using a Neptune plus MC-ICP-MS coupled with a GeoLas 2005 laser ablation system at GPMR-CUG. The isotopic data were acquired in static multi-collector mode with low resolution using Faraday collectors and a mass configuration array from 83Kr to 88Sr to monitor Kr, Rb, Er, Yb and Sr. Helium was used as the carrier gas and mixed with Ar by a T-connector before entering the ICP. Each spot analysis includes approximately 50 s of background acquisition followed by 50 s of data acquisition for each sample. The gas blank correction was made to eliminate the effect of Kr from the Ar and He supply, as well as the small, persistent yet stable Rb and Sr backgrounds from the torch and cones (Tong et al., 2016). The interference of 168Er2+ on 84Sr, 170Er2+ and 170Yb2+ on 85Rb, 172Yb2+ on 86Sr, and 174Yb2+ on 87Sr were corrected based on the measured signal intensities of 167Er2+, 173Yb2+, 84, 86, 87 and 88Sr and 85Rb and the natural isotope ratios of Er and Yb (Berglund & Wieser, 2011). The isobaric interference of 87Rb on 87Sr was corrected for by measuring the 85Rb signal intensity and using a user-specified 87Rb/85Rb ratio calculated according to reference glass StHs6/80-G. Finally, the 87Sr/86Sr ratio was normalized to 88Sr/86Sr = 0·1194 using the exponential correction law. Off-line selection and integration of analytical signals and mass-dependent calibrations were performed using ICPMSDataCal (Lin et al., 2016). The detailed calibration strategy for in situ Sr isotopic analysis by LA-MC-ICP-MS were reported in Tong et al. (2016). RESULTS Whole-rock major and trace element geochemistry Granitoids Whole-rock major and trace element compositions are listed in Table 2. The Tonglu Mesozoic granitoids are mainly monzodiorites, monzonites and quartz monzonites with SiO2 contents ranging from 52·2 wt % to 67·6 wt % (Fig. 4a). All the granitoids have relatively high alkali contents (K2O + Na2O = 4·20–8·03 wt %), and fall in the field of high-K calc-alkaline series (Fig. 4c and d). Combined with low alumina saturation indices (0·81 to 1) and the lack of typical peraluminous or alkaline mafic minerals, the monzodiorites, monzonites and quartz monzonites are considered as typical metaluminous I-type granitoids (Fig. 4b). The monzodiorites have SiO2 contents ranging from 52·2 wt % to 56·4 wt %. (Fig. 4a), and are characterized by high Fe2 O3T (7·93–9·99 wt %), MgO (3·18–4·29 wt %), CaO (6·.03–7·47 wt %), TiO2 (1·03–1·17 wt %), P2O5 (0·33–0·43 wt %) contents and high Mg# (=100*molar Mg/(Mg + Fe)) (42·9–47·2). The monzonites have relatively higher SiO2 contents (58·5–59·.5 wt %) and lower Fe2 O3T (6·42–7·48 wt %), MgO (1·67–2·15 wt %) contents than the monzodiorites. The SiO2-rich (63·5–67·6 wt %) quartz monzonites have low MgO (0·96–1·38 wt %), Fe2 O3T (3·64–5·08 wt %), TiO2 (0·50–7·70 wt %), P2O5 (0·16–0·25 wt %) contents and low Mg# (33·7–35·5). Table 2: Whole-rock major (wt %) and trace element (ppm) compositions of the Tonglu granitoids, MME and CRX Rock type Monzodiorite Quartz monzonite Sample 12TL-02 12TL-03 12TL-07 12TL-11 12TL-26 12TL-05 15TL-07 15TL-08 15TL-10 15TL-12 SiO2 52·21 53·17 54·37 55·04 56·41 67·62 67·31 64·00 66·85 67·34 TiO2 1·15 1·17 1·09 1·07 1·03 0·53 0·52 0·66 0·51 0·51 Al2O3 16·51 15·89 16·32 16·38 16·39 14·88 14·78 15·74 15·02 14·94 Fe2 O3T 9·99 9·51 9·32 8·16 7·93 3·72 3·82 4·83 3·72 3·68 MnO 0·16 0·15 0·14 0·14 0·14 0·09 0·08 0·10 0·08 0·08 MgO 4·27 4·29 3·54 3·52 3·18 1·03 0·98 1·34 0·99 0·96 CaO 6·75 7·47 6·00 6·13 6·03 2·45 2·70 3·24 2·79 2·75 Na2O 2·57 2·47 3·16 2·97 3·09 3·58 3·58 3·47 3·61 3·42 K2O 1·82 1·72 2·68 2·59 2·46 4·22 4·39 3·69 4·23 4·61 P2O5 0·40 0·43 0·35 0·33 0·40 0·17 0·17 0·23 0·16 0·17 LOI 3·23 2·15 2·52 2·78 1·76 1·03 1·19 0·86 0·64 0·64 Total 99·06 98·42 99·49 99·11 98·82 99·31 99·52 98·14 98·62 99·10 A/CNK 0·89 0·81 0·86 0·87 0·88 1·00 0·95 1·01 0·96 0·96 A/NK 2·67 2·68 2·01 2·13 2·12 1·42 1·39 1·62 1·43 1·41 Na2O+K2O 4·39 4·20 5·85 5·56 5·55 7·80 7·97 7·16 7·85 8·03 K2O/N2O 0·71 0·70 0·85 0·87 0·80 1·18 1·23 1·06 1·17 1·35 Mg# 45·8 47·2 42·9 46·1 44·3 35·3 33·7 35·5 34·6 34·1 Sc 21·7 25·7 18·4 17·9 17·0 8·97 8·71 11·34 8·61 8·21 V 228 232 202 192 190 40·7 39·2 55·5 37·9 38·0 Cr 25·7 17·0 16·4 15·7 14·9 5·39 5·38 8·60 5·15 4·96 Ni 16·3 18·3 11·1 10·2 9·82 4·16 4·46 5·45 4·10 4·26 Ga 20·6 19·5 19·9 20·1 20·0 18·7 18·4 19·6 18·7 18·6 Rb 62·4 55·6 93·7 88·6 81·2 152 158 135 157 147 Sr 502 509 499 466 472 239 235 305 259 247 Y 31·7 35·7 31·7 31·8 35·2 44·9 45·3 41·8 44·0 42·9 Zr 80·9 90·9 128 125 112 221 221 222 209 214 Nb 10·7 10·1 10·8 11·8 12·8 20·6 19·8 19·5 19·8 20·0 Ba 350 336 554 517 353 703 611 692 647 669 La 27·2 27·0 28·2 27·7 32·1 42·9 43·0 42·3 43·9 41·8 Ce 55·9 57·1 56·2 56·2 65·3 84·4 87 86 88 82 Pr 6·80 7·24 6·83 6·82 7·96 9·75 9·9 9·8 9·9 9·5 Nd 29·3 31·9 28·5 28·5 33·2 37·8 38·6 39·7 38·3 36·9 Sm 6·38 7·14 6·31 6·45 7·40 8·08 8·16 8·52 8·05 7·96 Eu 1·60 1·71 1·54 1·49 1·59 1·34 1·27 1·49 1·29 1·28 Gd 5·99 6·82 5·87 5·80 6·41 7·17 7·07 7·04 6·96 6·89 Tb 0·94 1·08 0·93 0·94 1·01 1·21 1·19 1·16 1·18 1·15 Dy 5·38 6·56 5·62 5·47 6·08 7·41 7·61 7·11 7·38 7·07 Ho 1·10 1·23 1·09 1·06 1·18 1·54 1·52 1·43 1·47 1·42 Er 2·97 3·26 2·99 2·92 3·20 4·13 4·35 4·00 4·10 4·16 Tm 0·44 0·49 0·45 0·44 0·46 0·68 0·69 0·62 0·66 0·63 Yb 2·87 3·07 2·78 2·90 3·21 4·49 4·42 4·00 4·31 4·15 Lu 0·42 0·44 0·43 0·42 0·48 0·65 0·63 0·57 0·66 0·64 Hf 2·44 2·79 3·53 3·54 3·29 6·15 6·17 5·97 5·99 5·83 Ta 0·82 0·74 0·81 0·81 0·99 1·67 1·61 1·30 1·49 1·56 Pb 13·3 10·0 9·61 10·6 21·0 20·9 21·8 18·3 22·1 22·4 Th 5·84 4·59 6·64 6·82 7·72 14·9 15·0 11·7 14·9 14·2 U 1·56 1·18 1·71 1·81 1·96 4·17 4·12 3·16 4·24 3·98 ∑REE 147 155 148 147 170 212 215 214 216 205 δEu 0·78 0·75 0·76 0·74 0·70 0·54 0·51 0·59 0·53 0·53 (La/Yb)N 6·81 6·33 7·28 6·86 7·17 6·86 6·98 7·58 7·32 7·22 Rock type Monzodiorite Quartz monzonite Sample 12TL-02 12TL-03 12TL-07 12TL-11 12TL-26 12TL-05 15TL-07 15TL-08 15TL-10 15TL-12 SiO2 52·21 53·17 54·37 55·04 56·41 67·62 67·31 64·00 66·85 67·34 TiO2 1·15 1·17 1·09 1·07 1·03 0·53 0·52 0·66 0·51 0·51 Al2O3 16·51 15·89 16·32 16·38 16·39 14·88 14·78 15·74 15·02 14·94 Fe2 O3T 9·99 9·51 9·32 8·16 7·93 3·72 3·82 4·83 3·72 3·68 MnO 0·16 0·15 0·14 0·14 0·14 0·09 0·08 0·10 0·08 0·08 MgO 4·27 4·29 3·54 3·52 3·18 1·03 0·98 1·34 0·99 0·96 CaO 6·75 7·47 6·00 6·13 6·03 2·45 2·70 3·24 2·79 2·75 Na2O 2·57 2·47 3·16 2·97 3·09 3·58 3·58 3·47 3·61 3·42 K2O 1·82 1·72 2·68 2·59 2·46 4·22 4·39 3·69 4·23 4·61 P2O5 0·40 0·43 0·35 0·33 0·40 0·17 0·17 0·23 0·16 0·17 LOI 3·23 2·15 2·52 2·78 1·76 1·03 1·19 0·86 0·64 0·64 Total 99·06 98·42 99·49 99·11 98·82 99·31 99·52 98·14 98·62 99·10 A/CNK 0·89 0·81 0·86 0·87 0·88 1·00 0·95 1·01 0·96 0·96 A/NK 2·67 2·68 2·01 2·13 2·12 1·42 1·39 1·62 1·43 1·41 Na2O+K2O 4·39 4·20 5·85 5·56 5·55 7·80 7·97 7·16 7·85 8·03 K2O/N2O 0·71 0·70 0·85 0·87 0·80 1·18 1·23 1·06 1·17 1·35 Mg# 45·8 47·2 42·9 46·1 44·3 35·3 33·7 35·5 34·6 34·1 Sc 21·7 25·7 18·4 17·9 17·0 8·97 8·71 11·34 8·61 8·21 V 228 232 202 192 190 40·7 39·2 55·5 37·9 38·0 Cr 25·7 17·0 16·4 15·7 14·9 5·39 5·38 8·60 5·15 4·96 Ni 16·3 18·3 11·1 10·2 9·82 4·16 4·46 5·45 4·10 4·26 Ga 20·6 19·5 19·9 20·1 20·0 18·7 18·4 19·6 18·7 18·6 Rb 62·4 55·6 93·7 88·6 81·2 152 158 135 157 147 Sr 502 509 499 466 472 239 235 305 259 247 Y 31·7 35·7 31·7 31·8 35·2 44·9 45·3 41·8 44·0 42·9 Zr 80·9 90·9 128 125 112 221 221 222 209 214 Nb 10·7 10·1 10·8 11·8 12·8 20·6 19·8 19·5 19·8 20·0 Ba 350 336 554 517 353 703 611 692 647 669 La 27·2 27·0 28·2 27·7 32·1 42·9 43·0 42·3 43·9 41·8 Ce 55·9 57·1 56·2 56·2 65·3 84·4 87 86 88 82 Pr 6·80 7·24 6·83 6·82 7·96 9·75 9·9 9·8 9·9 9·5 Nd 29·3 31·9 28·5 28·5 33·2 37·8 38·6 39·7 38·3 36·9 Sm 6·38 7·14 6·31 6·45 7·40 8·08 8·16 8·52 8·05 7·96 Eu 1·60 1·71 1·54 1·49 1·59 1·34 1·27 1·49 1·29 1·28 Gd 5·99 6·82 5·87 5·80 6·41 7·17 7·07 7·04 6·96 6·89 Tb 0·94 1·08 0·93 0·94 1·01 1·21 1·19 1·16 1·18 1·15 Dy 5·38 6·56 5·62 5·47 6·08 7·41 7·61 7·11 7·38 7·07 Ho 1·10 1·23 1·09 1·06 1·18 1·54 1·52 1·43 1·47 1·42 Er 2·97 3·26 2·99 2·92 3·20 4·13 4·35 4·00 4·10 4·16 Tm 0·44 0·49 0·45 0·44 0·46 0·68 0·69 0·62 0·66 0·63 Yb 2·87 3·07 2·78 2·90 3·21 4·49 4·42 4·00 4·31 4·15 Lu 0·42 0·44 0·43 0·42 0·48 0·65 0·63 0·57 0·66 0·64 Hf 2·44 2·79 3·53 3·54 3·29 6·15 6·17 5·97 5·99 5·83 Ta 0·82 0·74 0·81 0·81 0·99 1·67 1·61 1·30 1·49 1·56 Pb 13·3 10·0 9·61 10·6 21·0 20·9 21·8 18·3 22·1 22·4 Th 5·84 4·59 6·64 6·82 7·72 14·9 15·0 11·7 14·9 14·2 U 1·56 1·18 1·71 1·81 1·96 4·17 4·12 3·16 4·24 3·98 ∑REE 147 155 148 147 170 212 215 214 216 205 δEu 0·78 0·75 0·76 0·74 0·70 0·54 0·51 0·59 0·53 0·53 (La/Yb)N 6·81 6·33 7·28 6·86 7·17 6·86 6·98 7·58 7·32 7·22 Rock type MME dark rim of CRX CRX Sample 12TL-23-2 12TL-15 12TL-22-2 14ZJ58 15TL-01-2 15TL-09-1 14ZJ57 15TL-01-1 15TL-09-3 SiO2 53·24 57·31 57·98 59·77 54·86 62·74 65·34 64·72 65·78 TiO2 0·98 0·95 1·03 0·72 0·95 0·65 0·60 0·63 0·57 Al2O3 16·58 16·91 16·22 16·97 17·65 15·62 13·54 14·43 12·75 Fe2 O3T 8·29 7·36 7·73 7·20 8·57 6·22 4·06 3·75 5·31 MnO 0·19 0·15 0·15 0·04 0·09 0·16 0·19 0·07 0·31 MgO 3·51 2·51 2·54 2·23 3·24 2·63 1·86 1·95 2·47 CaO 6·23 5·21 4·68 4·99 5·96 5·31 12·58 8·57 9·80 Na2O 3·38 3·52 3·54 3·60 3·80 3·33 0·86 3·96 1·58 K2O 2·39 2·85 3·02 1·45 2·94 0·65 0·14 0·74 0·15 P2O5 0·27 0·35 0·30 0·15 0·17 0·13 0·18 0·16 0·16 LOI 3·50 2·23 2·43 1·12 0·94 0·60 0·45 0·86 0·37 Total 98·55 99·34 99·62 98·25 99·16 98·04 99·80 99·82 99·24 A/CNK 0·85 0·92 0·92 1·02 0·87 0·99 0·55 0·63 0·62 A/NK 2·04 1·90 1·78 2·26 1·87 2·53 8·64 1·98 4·62 Na2O+K2O 5·77 6·37 6·56 5·05 6·75 3·98 1·00 4·69 1·73 K2O/N2O 0·71 0·81 0·85 0·40 0·77 0·19 0·17 0·19 0·09 Mg# 45·6 40·3 39·4 38·1 42·8 45·6 47·5 50·7 48·0 Sc 20·5 20·8 19·9 16·8 16·5 15·1 10·9 12·7 9·96 V 180 122 141 128 158 110 77·5 78·1 71·1 Cr 9·64 7·06 4·52 88·9 101 73·1 62·1 67·9 51·4 Ni 10·0 5·30 7·69 39·9 88·5 41·3 39·9 53·1 31·4 Ga 20·2 21·4 20·8 23·3 23·9 21·3 16·6 18·0 14·6 Rb 91·3 100 108 81·2 112 32·5 5·93 34·6 6·71 Sr 435 444 396 235 368 222 298 297 325 Y 33·1 39·2 41·8 32·2 23·6 30·1 34·4 37·3 35·5 Zr 162 98·4 177 173 229 130 213 196 206 Nb 10·3 16·8 18·5 17·8 18·2 14·2 14·7 20·72 14·36 Ba 687 792 743 475 797 262 204 229 75·5 La 28·3 26·0 32·9 42·7 33·9 41·1 37·4 39·9 36·6 Ce 58·7 56·0 69·1 80·5 63·0 81·4 70·2 77·4 71·6 Pr 7·31 7·30 8·74 9·13 7·3 8·8 7·86 9·2 8·3 Nd 30·9 31·7 36·6 35·0 28·33 33·11 30·4 35·8 32·5 Sm 7·05 7·20 8·50 7·10 5·37 6·61 6·30 7·58 7·14 Eu 2·08 1·82 1·78 1·35 1·88 1·20 1·16 1·40 1·21 Gd 6·27 6·99 7·60 5·86 4·58 5·27 5·56 6·48 5·82 Tb 0·98 1·13 1·25 0·93 0·67 0·84 0·86 1·03 0·97 Dy 5·98 6·71 7·42 5·67 4·18 5·15 5·17 6·29 6·02 Ho 1·14 1·33 1·46 1·09 0·82 1·03 1·08 1·26 1·20 Er 3·05 3·77 3·94 3·13 2·31 2·88 3·21 3·56 3·33 Tm 0·48 0·55 0·59 0·49 0·37 0·48 0·46 0·56 0·49 Yb 2·91 3·67 3·78 3·06 2·49 2·94 3·15 3·66 3·27 Lu 0·43 0·54 0·59 0·47 0·40 0·44 0·45 0·53 0·49 Hf 4·19 2·77 4·61 4·70 6·34 3·85 5·69 5·27 5·42 Ta 0·59 1·02 1·05 1·38 1·00 1·16 1·37 1·42 1·41 Pb 22·1 15·6 15·7 29·8 19·7 14·9 6·70 9·00 19·0 Th 4·72 6·59 7·75 15·5 8·98 14·0 13·5 13·4 11·5 U 1·24 1·96 2·09 2·86 1·79 4·59 3·35 3·62 3·38 ∑REE 156 155 184 197 156 191 173 195 179 δEu 0·96 0·78 0·68 0·64 1·16 0·62 0·60 0·61 0·58 (La/Yb)N 6·97 5·08 6·25 10·0 9·76 10·0 8·51 7·82 8·04 Rock type MME dark rim of CRX CRX Sample 12TL-23-2 12TL-15 12TL-22-2 14ZJ58 15TL-01-2 15TL-09-1 14ZJ57 15TL-01-1 15TL-09-3 SiO2 53·24 57·31 57·98 59·77 54·86 62·74 65·34 64·72 65·78 TiO2 0·98 0·95 1·03 0·72 0·95 0·65 0·60 0·63 0·57 Al2O3 16·58 16·91 16·22 16·97 17·65 15·62 13·54 14·43 12·75 Fe2 O3T 8·29 7·36 7·73 7·20 8·57 6·22 4·06 3·75 5·31 MnO 0·19 0·15 0·15 0·04 0·09 0·16 0·19 0·07 0·31 MgO 3·51 2·51 2·54 2·23 3·24 2·63 1·86 1·95 2·47 CaO 6·23 5·21 4·68 4·99 5·96 5·31 12·58 8·57 9·80 Na2O 3·38 3·52 3·54 3·60 3·80 3·33 0·86 3·96 1·58 K2O 2·39 2·85 3·02 1·45 2·94 0·65 0·14 0·74 0·15 P2O5 0·27 0·35 0·30 0·15 0·17 0·13 0·18 0·16 0·16 LOI 3·50 2·23 2·43 1·12 0·94 0·60 0·45 0·86 0·37 Total 98·55 99·34 99·62 98·25 99·16 98·04 99·80 99·82 99·24 A/CNK 0·85 0·92 0·92 1·02 0·87 0·99 0·55 0·63 0·62 A/NK 2·04 1·90 1·78 2·26 1·87 2·53 8·64 1·98 4·62 Na2O+K2O 5·77 6·37 6·56 5·05 6·75 3·98 1·00 4·69 1·73 K2O/N2O 0·71 0·81 0·85 0·40 0·77 0·19 0·17 0·19 0·09 Mg# 45·6 40·3 39·4 38·1 42·8 45·6 47·5 50·7 48·0 Sc 20·5 20·8 19·9 16·8 16·5 15·1 10·9 12·7 9·96 V 180 122 141 128 158 110 77·5 78·1 71·1 Cr 9·64 7·06 4·52 88·9 101 73·1 62·1 67·9 51·4 Ni 10·0 5·30 7·69 39·9 88·5 41·3 39·9 53·1 31·4 Ga 20·2 21·4 20·8 23·3 23·9 21·3 16·6 18·0 14·6 Rb 91·3 100 108 81·2 112 32·5 5·93 34·6 6·71 Sr 435 444 396 235 368 222 298 297 325 Y 33·1 39·2 41·8 32·2 23·6 30·1 34·4 37·3 35·5 Zr 162 98·4 177 173 229 130 213 196 206 Nb 10·3 16·8 18·5 17·8 18·2 14·2 14·7 20·72 14·36 Ba 687 792 743 475 797 262 204 229 75·5 La 28·3 26·0 32·9 42·7 33·9 41·1 37·4 39·9 36·6 Ce 58·7 56·0 69·1 80·5 63·0 81·4 70·2 77·4 71·6 Pr 7·31 7·30 8·74 9·13 7·3 8·8 7·86 9·2 8·3 Nd 30·9 31·7 36·6 35·0 28·33 33·11 30·4 35·8 32·5 Sm 7·05 7·20 8·50 7·10 5·37 6·61 6·30 7·58 7·14 Eu 2·08 1·82 1·78 1·35 1·88 1·20 1·16 1·40 1·21 Gd 6·27 6·99 7·60 5·86 4·58 5·27 5·56 6·48 5·82 Tb 0·98 1·13 1·25 0·93 0·67 0·84 0·86 1·03 0·97 Dy 5·98 6·71 7·42 5·67 4·18 5·15 5·17 6·29 6·02 Ho 1·14 1·33 1·46 1·09 0·82 1·03 1·08 1·26 1·20 Er 3·05 3·77 3·94 3·13 2·31 2·88 3·21 3·56 3·33 Tm 0·48 0·55 0·59 0·49 0·37 0·48 0·46 0·56 0·49 Yb 2·91 3·67 3·78 3·06 2·49 2·94 3·15 3·66 3·27 Lu 0·43 0·54 0·59 0·47 0·40 0·44 0·45 0·53 0·49 Hf 4·19 2·77 4·61 4·70 6·34 3·85 5·69 5·27 5·42 Ta 0·59 1·02 1·05 1·38 1·00 1·16 1·37 1·42 1·41 Pb 22·1 15·6 15·7 29·8 19·7 14·9 6·70 9·00 19·0 Th 4·72 6·59 7·75 15·5 8·98 14·0 13·5 13·4 11·5 U 1·24 1·96 2·09 2·86 1·79 4·59 3·35 3·62 3·38 ∑REE 156 155 184 197 156 191 173 195 179 δEu 0·96 0·78 0·68 0·64 1·16 0·62 0·60 0·61 0·58 (La/Yb)N 6·97 5·08 6·25 10·0 9·76 10·0 8·51 7·82 8·04 Rock type Quartz monzonite Monzonite MME Sample 15TL-13 15TL-14 12TL-12 12TL-22-1 12TL-23-1 12TL-20-2 15TL-01-3 12TL-16 12TL-17 12TL-18 SiO2 65·93 63·46 59·21 59·03 58·47 58·49 59·53 53·92 52·76 54·00 TiO2 0·50 0·70 0·95 0·98 1·02 1·00 0·99 0·97 0·99 0·91 Al2O3 15·26 15·76 17·00 16·26 16·30 16·23 16·40 16·12 16·40 15·82 Fe2 O3T 3·64 5·08 6·42 6·77 6·92 7·48 7·05 8·10 8·66 8·34 MnO 0·08 0·10 0·13 0·13 0·13 0·13 0·12 0·18 0·21 0·20 MgO 0·99 1·38 1·67 2·10 2·13 2·15 2·02 3·64 3·72 3·97 CaO 2·74 3·32 4·40 4·46 4·77 4·52 4·89 6·77 6·59 6·13 Na2O 3·49 3·62 3·61 3·25 3·16 3·33 3·37 3·22 3·30 3·08 K2O 4·22 3·74 3·43 3·66 3·50 3·30 2·84 2·50 2·23 2·48 P2O5 0·16 0·25 0·35 0·34 0·36 0·36 0·36 0·26 0·26 0·26 LOI 1·20 1·30 1·69 2·05 2·56 2·48 1·45 3·35 4·07 3·40 Total 98·21 98·70 98·86 99·03 99·31 99·45 99·03 99·01 99·18 98·60 A/CNK 1·00 0·98 0·96 0·93 0·92 0·94 0·94 0·79 0·83 0·84 A/NK 1·48 1·58 1·76 1·75 1·81 1·79 1·90 2·01 2·09 2·04 Na2O+K2O 7·72 7·35 7·04 6·91 6·66 6·63 6·21 5·72 5·52 5·56 K2O/N2O 1·21 1·03 0·95 1·12 1·11 0·99 0·84 0·77 0·68 0·80 Mg# 35·0 35·0 34·0 38·1 37·9 36·3 36·3 47·1 46·0 48·5 Sc 8·59 11·37 16·3 16·4 16·4 19·9 12·4 20·8 21·0 21·7 V 39·2 57·4 78·5 101 105 141 93·1 166 191 153 Cr 4·96 7·98 9·66 15·4 16·3 4·52 16·9 12·0 11·3 54·9 Ni 4·21 6·02 5·65 9·02 9·30 7·69 14·3 11·2 10·5 26·8 Ga 18·4 20·0 21·5 21·0 20·8 20·8 19·9 18·6 20·1 18·7 Rb 163 136 120 116 109 108 85 83·8 85·5 85·1 Sr 246 304 424 384 418 396 402 413 430 380 Y 43·8 44·3 40·8 44·4 39·4 41·8 34·5 31·0 34·2 43·2 Zr 199 246 245 234 242 177 188 156 176 115 Nb 19·5 20·3 19·0 18·2 17·6 18·5 20·6 8·50 10·2 12·3 Ba 671 786 885 715 757 743 530 662 634 718 La 41·4 45·4 38·9 50·1 42·1 32·9 32·8 23·6 25·5 29·3 Ce 84 93 78·7 98·3 83·0 69·1 67·3 47·4 54·3 64·1 Pr 9·5 10·6 9·62 11·5 9·85 8·74 8·26 5·86 7·07 8·39 Nd 37·3 42·5 40·1 46·7 40·6 36·6 33·9 25·1 30·2 36·6 Sm 8·05 8·88 8·75 9·66 8·45 8·50 7·38 5·65 6·89 8·58 Eu 1·28 1·49 2·19 1·93 2·06 1·78 1·77 1·96 2·05 1·90 Gd 6·78 7·57 7·61 8·41 7·39 7·60 6·14 5·43 6·35 7·83 Tb 1·15 1·23 1·22 1·35 1·17 1·25 0·98 0·88 1·03 1·26 Dy 7·33 7·66 7·28 7·92 6·85 7·42 5·82 5·25 6·13 7·65 Ho 1·45 1·49 1·35 1·50 1·39 1·46 1·17 1·07 1·18 1·48 Er 4·12 4·19 3·81 4·15 3·67 3·94 3·32 2·96 3·30 4·06 Tm 0·64 0·64 0·58 0·62 0·54 0·59 0·52 0·44 0·48 0·59 Yb 4·16 4·18 3·68 3·95 3·59 3·78 3·28 3·00 3·05 3·97 Lu 0·62 0·63 0·53 0·57 0·51 0·59 0·50 0·43 0·44 0·58 Hf 5·72 6·57 6·12 6·00 6·06 4·61 5·08 4·08 4·53 3·48 Ta 1·50 1·37 1·17 1·12 1·07 1·05 1·19 0·58 0·59 0·85 Pb 22·8 18·8 15·4 16·7 16·0 15·7 15·8 29·5 18·6 17·2 Th 14·6 12·4 8·05 9·49 7·61 7·75 7·21 3·32 4·27 5·34 U 4·16 3·32 2·14 2·04 1·79 2·09 2·05 0·89 1·23 1·45 ∑REE 207 230 204 247 211 204 173 129 148 176 δEu 0·53 0·56 0·82 0·65 0·80 0·79 0·80 1·08 0·95 0·71 (La/Yb)N 7·14 7·79 7·58 9·09 8·41 8·14 7·19 5·64 6·00 5·30 Rock type Quartz monzonite Monzonite MME Sample 15TL-13 15TL-14 12TL-12 12TL-22-1 12TL-23-1 12TL-20-2 15TL-01-3 12TL-16 12TL-17 12TL-18 SiO2 65·93 63·46 59·21 59·03 58·47 58·49 59·53 53·92 52·76 54·00 TiO2 0·50 0·70 0·95 0·98 1·02 1·00 0·99 0·97 0·99 0·91 Al2O3 15·26 15·76 17·00 16·26 16·30 16·23 16·40 16·12 16·40 15·82 Fe2 O3T 3·64 5·08 6·42 6·77 6·92 7·48 7·05 8·10 8·66 8·34 MnO 0·08 0·10 0·13 0·13 0·13 0·13 0·12 0·18 0·21 0·20 MgO 0·99 1·38 1·67 2·10 2·13 2·15 2·02 3·64 3·72 3·97 CaO 2·74 3·32 4·40 4·46 4·77 4·52 4·89 6·77 6·59 6·13 Na2O 3·49 3·62 3·61 3·25 3·16 3·33 3·37 3·22 3·30 3·08 K2O 4·22 3·74 3·43 3·66 3·50 3·30 2·84 2·50 2·23 2·48 P2O5 0·16 0·25 0·35 0·34 0·36 0·36 0·36 0·26 0·26 0·26 LOI 1·20 1·30 1·69 2·05 2·56 2·48 1·45 3·35 4·07 3·40 Total 98·21 98·70 98·86 99·03 99·31 99·45 99·03 99·01 99·18 98·60 A/CNK 1·00 0·98 0·96 0·93 0·92 0·94 0·94 0·79 0·83 0·84 A/NK 1·48 1·58 1·76 1·75 1·81 1·79 1·90 2·01 2·09 2·04 Na2O+K2O 7·72 7·35 7·04 6·91 6·66 6·63 6·21 5·72 5·52 5·56 K2O/N2O 1·21 1·03 0·95 1·12 1·11 0·99 0·84 0·77 0·68 0·80 Mg# 35·0 35·0 34·0 38·1 37·9 36·3 36·3 47·1 46·0 48·5 Sc 8·59 11·37 16·3 16·4 16·4 19·9 12·4 20·8 21·0 21·7 V 39·2 57·4 78·5 101 105 141 93·1 166 191 153 Cr 4·96 7·98 9·66 15·4 16·3 4·52 16·9 12·0 11·3 54·9 Ni 4·21 6·02 5·65 9·02 9·30 7·69 14·3 11·2 10·5 26·8 Ga 18·4 20·0 21·5 21·0 20·8 20·8 19·9 18·6 20·1 18·7 Rb 163 136 120 116 109 108 85 83·8 85·5 85·1 Sr 246 304 424 384 418 396 402 413 430 380 Y 43·8 44·3 40·8 44·4 39·4 41·8 34·5 31·0 34·2 43·2 Zr 199 246 245 234 242 177 188 156 176 115 Nb 19·5 20·3 19·0 18·2 17·6 18·5 20·6 8·50 10·2 12·3 Ba 671 786 885 715 757 743 530 662 634 718 La 41·4 45·4 38·9 50·1 42·1 32·9 32·8 23·6 25·5 29·3 Ce 84 93 78·7 98·3 83·0 69·1 67·3 47·4 54·3 64·1 Pr 9·5 10·6 9·62 11·5 9·85 8·74 8·26 5·86 7·07 8·39 Nd 37·3 42·5 40·1 46·7 40·6 36·6 33·9 25·1 30·2 36·6 Sm 8·05 8·88 8·75 9·66 8·45 8·50 7·38 5·65 6·89 8·58 Eu 1·28 1·49 2·19 1·93 2·06 1·78 1·77 1·96 2·05 1·90 Gd 6·78 7·57 7·61 8·41 7·39 7·60 6·14 5·43 6·35 7·83 Tb 1·15 1·23 1·22 1·35 1·17 1·25 0·98 0·88 1·03 1·26 Dy 7·33 7·66 7·28 7·92 6·85 7·42 5·82 5·25 6·13 7·65 Ho 1·45 1·49 1·35 1·50 1·39 1·46 1·17 1·07 1·18 1·48 Er 4·12 4·19 3·81 4·15 3·67 3·94 3·32 2·96 3·30 4·06 Tm 0·64 0·64 0·58 0·62 0·54 0·59 0·52 0·44 0·48 0·59 Yb 4·16 4·18 3·68 3·95 3·59 3·78 3·28 3·00 3·05 3·97 Lu 0·62 0·63 0·53 0·57 0·51 0·59 0·50 0·43 0·44 0·58 Hf 5·72 6·57 6·12 6·00 6·06 4·61 5·08 4·08 4·53 3·48 Ta 1·50 1·37 1·17 1·12 1·07 1·05 1·19 0·58 0·59 0·85 Pb 22·8 18·8 15·4 16·7 16·0 15·7 15·8 29·5 18·6 17·2 Th 14·6 12·4 8·05 9·49 7·61 7·75 7·21 3·32 4·27 5·34 U 4·16 3·32 2·14 2·04 1·79 2·09 2·05 0·89 1·23 1·45 ∑REE 207 230 204 247 211 204 173 129 148 176 δEu 0·53 0·56 0·82 0·65 0·80 0·79 0·80 1·08 0·95 0·71 (La/Yb)N 7·14 7·79 7·58 9·09 8·41 8·14 7·19 5·64 6·00 5·30 LOI, loss of ignition; A/NK, molar Al2O3/(Na2O + K2O); A/CNK, molar Al2O3/(CaO + Na2O + K2O); Mg# = 100*molar Mg/(Mg + Fe). Table 2: Whole-rock major (wt %) and trace element (ppm) compositions of the Tonglu granitoids, MME and CRX Rock type Monzodiorite Quartz monzonite Sample 12TL-02 12TL-03 12TL-07 12TL-11 12TL-26 12TL-05 15TL-07 15TL-08 15TL-10 15TL-12 SiO2 52·21 53·17 54·37 55·04 56·41 67·62 67·31 64·00 66·85 67·34 TiO2 1·15 1·17 1·09 1·07 1·03 0·53 0·52 0·66 0·51 0·51 Al2O3 16·51 15·89 16·32 16·38 16·39 14·88 14·78 15·74 15·02 14·94 Fe2 O3T 9·99 9·51 9·32 8·16 7·93 3·72 3·82 4·83 3·72 3·68 MnO 0·16 0·15 0·14 0·14 0·14 0·09 0·08 0·10 0·08 0·08 MgO 4·27 4·29 3·54 3·52 3·18 1·03 0·98 1·34 0·99 0·96 CaO 6·75 7·47 6·00 6·13 6·03 2·45 2·70 3·24 2·79 2·75 Na2O 2·57 2·47 3·16 2·97 3·09 3·58 3·58 3·47 3·61 3·42 K2O 1·82 1·72 2·68 2·59 2·46 4·22 4·39 3·69 4·23 4·61 P2O5 0·40 0·43 0·35 0·33 0·40 0·17 0·17 0·23 0·16 0·17 LOI 3·23 2·15 2·52 2·78 1·76 1·03 1·19 0·86 0·64 0·64 Total 99·06 98·42 99·49 99·11 98·82 99·31 99·52 98·14 98·62 99·10 A/CNK 0·89 0·81 0·86 0·87 0·88 1·00 0·95 1·01 0·96 0·96 A/NK 2·67 2·68 2·01 2·13 2·12 1·42 1·39 1·62 1·43 1·41 Na2O+K2O 4·39 4·20 5·85 5·56 5·55 7·80 7·97 7·16 7·85 8·03 K2O/N2O 0·71 0·70 0·85 0·87 0·80 1·18 1·23 1·06 1·17 1·35 Mg# 45·8 47·2 42·9 46·1 44·3 35·3 33·7 35·5 34·6 34·1 Sc 21·7 25·7 18·4 17·9 17·0 8·97 8·71 11·34 8·61 8·21 V 228 232 202 192 190 40·7 39·2 55·5 37·9 38·0 Cr 25·7 17·0 16·4 15·7 14·9 5·39 5·38 8·60 5·15 4·96 Ni 16·3 18·3 11·1 10·2 9·82 4·16 4·46 5·45 4·10 4·26 Ga 20·6 19·5 19·9 20·1 20·0 18·7 18·4 19·6 18·7 18·6 Rb 62·4 55·6 93·7 88·6 81·2 152 158 135 157 147 Sr 502 509 499 466 472 239 235 305 259 247 Y 31·7 35·7 31·7 31·8 35·2 44·9 45·3 41·8 44·0 42·9 Zr 80·9 90·9 128 125 112 221 221 222 209 214 Nb 10·7 10·1 10·8 11·8 12·8 20·6 19·8 19·5 19·8 20·0 Ba 350 336 554 517 353 703 611 692 647 669 La 27·2 27·0 28·2 27·7 32·1 42·9 43·0 42·3 43·9 41·8 Ce 55·9 57·1 56·2 56·2 65·3 84·4 87 86 88 82 Pr 6·80 7·24 6·83 6·82 7·96 9·75 9·9 9·8 9·9 9·5 Nd 29·3 31·9 28·5 28·5 33·2 37·8 38·6 39·7 38·3 36·9 Sm 6·38 7·14 6·31 6·45 7·40 8·08 8·16 8·52 8·05 7·96 Eu 1·60 1·71 1·54 1·49 1·59 1·34 1·27 1·49 1·29 1·28 Gd 5·99 6·82 5·87 5·80 6·41 7·17 7·07 7·04 6·96 6·89 Tb 0·94 1·08 0·93 0·94 1·01 1·21 1·19 1·16 1·18 1·15 Dy 5·38 6·56 5·62 5·47 6·08 7·41 7·61 7·11 7·38 7·07 Ho 1·10 1·23 1·09 1·06 1·18 1·54 1·52 1·43 1·47 1·42 Er 2·97 3·26 2·99 2·92 3·20 4·13 4·35 4·00 4·10 4·16 Tm 0·44 0·49 0·45 0·44 0·46 0·68 0·69 0·62 0·66 0·63 Yb 2·87 3·07 2·78 2·90 3·21 4·49 4·42 4·00 4·31 4·15 Lu 0·42 0·44 0·43 0·42 0·48 0·65 0·63 0·57 0·66 0·64 Hf 2·44 2·79 3·53 3·54 3·29 6·15 6·17 5·97 5·99 5·83 Ta 0·82 0·74 0·81 0·81 0·99 1·67 1·61 1·30 1·49 1·56 Pb 13·3 10·0 9·61 10·6 21·0 20·9 21·8 18·3 22·1 22·4 Th 5·84 4·59 6·64 6·82 7·72 14·9 15·0 11·7 14·9 14·2 U 1·56 1·18 1·71 1·81 1·96 4·17 4·12 3·16 4·24 3·98 ∑REE 147 155 148 147 170 212 215 214 216 205 δEu 0·78 0·75 0·76 0·74 0·70 0·54 0·51 0·59 0·53 0·53 (La/Yb)N 6·81 6·33 7·28 6·86 7·17 6·86 6·98 7·58 7·32 7·22 Rock type Monzodiorite Quartz monzonite Sample 12TL-02 12TL-03 12TL-07 12TL-11 12TL-26 12TL-05 15TL-07 15TL-08 15TL-10 15TL-12 SiO2 52·21 53·17 54·37 55·04 56·41 67·62 67·31 64·00 66·85 67·34 TiO2 1·15 1·17 1·09 1·07 1·03 0·53 0·52 0·66 0·51 0·51 Al2O3 16·51 15·89 16·32 16·38 16·39 14·88 14·78 15·74 15·02 14·94 Fe2 O3T 9·99 9·51 9·32 8·16 7·93 3·72 3·82 4·83 3·72 3·68 MnO 0·16 0·15 0·14 0·14 0·14 0·09 0·08 0·10 0·08 0·08 MgO 4·27 4·29 3·54 3·52 3·18 1·03 0·98 1·34 0·99 0·96 CaO 6·75 7·47 6·00 6·13 6·03 2·45 2·70 3·24 2·79 2·75 Na2O 2·57 2·47 3·16 2·97 3·09 3·58 3·58 3·47 3·61 3·42 K2O 1·82 1·72 2·68 2·59 2·46 4·22 4·39 3·69 4·23 4·61 P2O5 0·40 0·43 0·35 0·33 0·40 0·17 0·17 0·23 0·16 0·17 LOI 3·23 2·15 2·52 2·78 1·76 1·03 1·19 0·86 0·64 0·64 Total 99·06 98·42 99·49 99·11 98·82 99·31 99·52 98·14 98·62 99·10 A/CNK 0·89 0·81 0·86 0·87 0·88 1·00 0·95 1·01 0·96 0·96 A/NK 2·67 2·68 2·01 2·13 2·12 1·42 1·39 1·62 1·43 1·41 Na2O+K2O 4·39 4·20 5·85 5·56 5·55 7·80 7·97 7·16 7·85 8·03 K2O/N2O 0·71 0·70 0·85 0·87 0·80 1·18 1·23 1·06 1·17 1·35 Mg# 45·8 47·2 42·9 46·1 44·3 35·3 33·7 35·5 34·6 34·1 Sc 21·7 25·7 18·4 17·9 17·0 8·97 8·71 11·34 8·61 8·21 V 228 232 202 192 190 40·7 39·2 55·5 37·9 38·0 Cr 25·7 17·0 16·4 15·7 14·9 5·39 5·38 8·60 5·15 4·96 Ni 16·3 18·3 11·1 10·2 9·82 4·16 4·46 5·45 4·10 4·26 Ga 20·6 19·5 19·9 20·1 20·0 18·7 18·4 19·6 18·7 18·6 Rb 62·4 55·6 93·7 88·6 81·2 152 158 135 157 147 Sr 502 509 499 466 472 239 235 305 259 247 Y 31·7 35·7 31·7 31·8 35·2 44·9 45·3 41·8 44·0 42·9 Zr 80·9 90·9 128 125 112 221 221 222 209 214 Nb 10·7 10·1 10·8 11·8 12·8 20·6 19·8 19·5 19·8 20·0 Ba 350 336 554 517 353 703 611 692 647 669 La 27·2 27·0 28·2 27·7 32·1 42·9 43·0 42·3 43·9 41·8 Ce 55·9 57·1 56·2 56·2 65·3 84·4 87 86 88 82 Pr 6·80 7·24 6·83 6·82 7·96 9·75 9·9 9·8 9·9 9·5 Nd 29·3 31·9 28·5 28·5 33·2 37·8 38·6 39·7 38·3 36·9 Sm 6·38 7·14 6·31 6·45 7·40 8·08 8·16 8·52 8·05 7·96 Eu 1·60 1·71 1·54 1·49 1·59 1·34 1·27 1·49 1·29 1·28 Gd 5·99 6·82 5·87 5·80 6·41 7·17 7·07 7·04 6·96 6·89 Tb 0·94 1·08 0·93 0·94 1·01 1·21 1·19 1·16 1·18 1·15 Dy 5·38 6·56 5·62 5·47 6·08 7·41 7·61 7·11 7·38 7·07 Ho 1·10 1·23 1·09 1·06 1·18 1·54 1·52 1·43 1·47 1·42 Er 2·97 3·26 2·99 2·92 3·20 4·13 4·35 4·00 4·10 4·16 Tm 0·44 0·49 0·45 0·44 0·46 0·68 0·69 0·62 0·66 0·63 Yb 2·87 3·07 2·78 2·90 3·21 4·49 4·42 4·00 4·31 4·15 Lu 0·42 0·44 0·43 0·42 0·48 0·65 0·63 0·57 0·66 0·64 Hf 2·44 2·79 3·53 3·54 3·29 6·15 6·17 5·97 5·99 5·83 Ta 0·82 0·74 0·81 0·81 0·99 1·67 1·61 1·30 1·49 1·56 Pb 13·3 10·0 9·61 10·6 21·0 20·9 21·8 18·3 22·1 22·4 Th 5·84 4·59 6·64 6·82 7·72 14·9 15·0 11·7 14·9 14·2 U 1·56 1·18 1·71 1·81 1·96 4·17 4·12 3·16 4·24 3·98 ∑REE 147 155 148 147 170 212 215 214 216 205 δEu 0·78 0·75 0·76 0·74 0·70 0·54 0·51 0·59 0·53 0·53 (La/Yb)N 6·81 6·33 7·28 6·86 7·17 6·86 6·98 7·58 7·32 7·22 Rock type MME dark rim of CRX CRX Sample 12TL-23-2 12TL-15 12TL-22-2 14ZJ58 15TL-01-2 15TL-09-1 14ZJ57 15TL-01-1 15TL-09-3 SiO2 53·24 57·31 57·98 59·77 54·86 62·74 65·34 64·72 65·78 TiO2 0·98 0·95 1·03 0·72 0·95 0·65 0·60 0·63 0·57 Al2O3 16·58 16·91 16·22 16·97 17·65 15·62 13·54 14·43 12·75 Fe2 O3T 8·29 7·36 7·73 7·20 8·57 6·22 4·06 3·75 5·31 MnO 0·19 0·15 0·15 0·04 0·09 0·16 0·19 0·07 0·31 MgO 3·51 2·51 2·54 2·23 3·24 2·63 1·86 1·95 2·47 CaO 6·23 5·21 4·68 4·99 5·96 5·31 12·58 8·57 9·80 Na2O 3·38 3·52 3·54 3·60 3·80 3·33 0·86 3·96 1·58 K2O 2·39 2·85 3·02 1·45 2·94 0·65 0·14 0·74 0·15 P2O5 0·27 0·35 0·30 0·15 0·17 0·13 0·18 0·16 0·16 LOI 3·50 2·23 2·43 1·12 0·94 0·60 0·45 0·86 0·37 Total 98·55 99·34 99·62 98·25 99·16 98·04 99·80 99·82 99·24 A/CNK 0·85 0·92 0·92 1·02 0·87 0·99 0·55 0·63 0·62 A/NK 2·04 1·90 1·78 2·26 1·87 2·53 8·64 1·98 4·62 Na2O+K2O 5·77 6·37 6·56 5·05 6·75 3·98 1·00 4·69 1·73 K2O/N2O 0·71 0·81 0·85 0·40 0·77 0·19 0·17 0·19 0·09 Mg# 45·6 40·3 39·4 38·1 42·8 45·6 47·5 50·7 48·0 Sc 20·5 20·8 19·9 16·8 16·5 15·1 10·9 12·7 9·96 V 180 122 141 128 158 110 77·5 78·1 71·1 Cr 9·64 7·06 4·52 88·9 101 73·1 62·1 67·9 51·4 Ni 10·0 5·30 7·69 39·9 88·5 41·3 39·9 53·1 31·4 Ga 20·2 21·4 20·8 23·3 23·9 21·3 16·6 18·0 14·6 Rb 91·3 100 108 81·2 112 32·5 5·93 34·6 6·71 Sr 435 444 396 235 368 222 298 297 325 Y 33·1 39·2 41·8 32·2 23·6 30·1 34·4 37·3 35·5 Zr 162 98·4 177 173 229 130 213 196 206 Nb 10·3 16·8 18·5 17·8 18·2 14·2 14·7 20·72 14·36 Ba 687 792 743 475 797 262 204 229 75·5 La 28·3 26·0 32·9 42·7 33·9 41·1 37·4 39·9 36·6 Ce 58·7 56·0 69·1 80·5 63·0 81·4 70·2 77·4 71·6 Pr 7·31 7·30 8·74 9·13 7·3 8·8 7·86 9·2 8·3 Nd 30·9 31·7 36·6 35·0 28·33 33·11 30·4 35·8 32·5 Sm 7·05 7·20 8·50 7·10 5·37 6·61 6·30 7·58 7·14 Eu 2·08 1·82 1·78 1·35 1·88 1·20 1·16 1·40 1·21 Gd 6·27 6·99 7·60 5·86 4·58 5·27 5·56 6·48 5·82 Tb 0·98 1·13 1·25 0·93 0·67 0·84 0·86 1·03 0·97 Dy 5·98 6·71 7·42 5·67 4·18 5·15 5·17 6·29 6·02 Ho 1·14 1·33 1·46 1·09 0·82 1·03 1·08 1·26 1·20 Er 3·05 3·77 3·94 3·13 2·31 2·88 3·21 3·56 3·33 Tm 0·48 0·55 0·59 0·49 0·37 0·48 0·46 0·56 0·49 Yb 2·91 3·67 3·78 3·06 2·49 2·94 3·15 3·66 3·27 Lu 0·43 0·54 0·59 0·47 0·40 0·44 0·45 0·53 0·49 Hf 4·19 2·77 4·61 4·70 6·34 3·85 5·69 5·27 5·42 Ta 0·59 1·02 1·05 1·38 1·00 1·16 1·37 1·42 1·41 Pb 22·1 15·6 15·7 29·8 19·7 14·9 6·70 9·00 19·0 Th 4·72 6·59 7·75 15·5 8·98 14·0 13·5 13·4 11·5 U 1·24 1·96 2·09 2·86 1·79 4·59 3·35 3·62 3·38 ∑REE 156 155 184 197 156 191 173 195 179 δEu 0·96 0·78 0·68 0·64 1·16 0·62 0·60 0·61 0·58 (La/Yb)N 6·97 5·08 6·25 10·0 9·76 10·0 8·51 7·82 8·04 Rock type MME dark rim of CRX CRX Sample 12TL-23-2 12TL-15 12TL-22-2 14ZJ58 15TL-01-2 15TL-09-1 14ZJ57 15TL-01-1 15TL-09-3 SiO2 53·24 57·31 57·98 59·77 54·86 62·74 65·34 64·72 65·78 TiO2 0·98 0·95 1·03 0·72 0·95 0·65 0·60 0·63 0·57 Al2O3 16·58 16·91 16·22 16·97 17·65 15·62 13·54 14·43 12·75 Fe2 O3T 8·29 7·36 7·73 7·20 8·57 6·22 4·06 3·75 5·31 MnO 0·19 0·15 0·15 0·04 0·09 0·16 0·19 0·07 0·31 MgO 3·51 2·51 2·54 2·23 3·24 2·63 1·86 1·95 2·47 CaO 6·23 5·21 4·68 4·99 5·96 5·31 12·58 8·57 9·80 Na2O 3·38 3·52 3·54 3·60 3·80 3·33 0·86 3·96 1·58 K2O 2·39 2·85 3·02 1·45 2·94 0·65 0·14 0·74 0·15 P2O5 0·27 0·35 0·30 0·15 0·17 0·13 0·18 0·16 0·16 LOI 3·50 2·23 2·43 1·12 0·94 0·60 0·45 0·86 0·37 Total 98·55 99·34 99·62 98·25 99·16 98·04 99·80 99·82 99·24 A/CNK 0·85 0·92 0·92 1·02 0·87 0·99 0·55 0·63 0·62 A/NK 2·04 1·90 1·78 2·26 1·87 2·53 8·64 1·98 4·62 Na2O+K2O 5·77 6·37 6·56 5·05 6·75 3·98 1·00 4·69 1·73 K2O/N2O 0·71 0·81 0·85 0·40 0·77 0·19 0·17 0·19 0·09 Mg# 45·6 40·3 39·4 38·1 42·8 45·6 47·5 50·7 48·0 Sc 20·5 20·8 19·9 16·8 16·5 15·1 10·9 12·7 9·96 V 180 122 141 128 158 110 77·5 78·1 71·1 Cr 9·64 7·06 4·52 88·9 101 73·1 62·1 67·9 51·4 Ni 10·0 5·30 7·69 39·9 88·5 41·3 39·9 53·1 31·4 Ga 20·2 21·4 20·8 23·3 23·9 21·3 16·6 18·0 14·6 Rb 91·3 100 108 81·2 112 32·5 5·93 34·6 6·71 Sr 435 444 396 235 368 222 298 297 325 Y 33·1 39·2 41·8 32·2 23·6 30·1 34·4 37·3 35·5 Zr 162 98·4 177 173 229 130 213 196 206 Nb 10·3 16·8 18·5 17·8 18·2 14·2 14·7 20·72 14·36 Ba 687 792 743 475 797 262 204 229 75·5 La 28·3 26·0 32·9 42·7 33·9 41·1 37·4 39·9 36·6 Ce 58·7 56·0 69·1 80·5 63·0 81·4 70·2 77·4 71·6 Pr 7·31 7·30 8·74 9·13 7·3 8·8 7·86 9·2 8·3 Nd 30·9 31·7 36·6 35·0 28·33 33·11 30·4 35·8 32·5 Sm 7·05 7·20 8·50 7·10 5·37 6·61 6·30 7·58 7·14 Eu 2·08 1·82 1·78 1·35 1·88 1·20 1·16 1·40 1·21 Gd 6·27 6·99 7·60 5·86 4·58 5·27 5·56 6·48 5·82 Tb 0·98 1·13 1·25 0·93 0·67 0·84 0·86 1·03 0·97 Dy 5·98 6·71 7·42 5·67 4·18 5·15 5·17 6·29 6·02 Ho 1·14 1·33 1·46 1·09 0·82 1·03 1·08 1·26 1·20 Er 3·05 3·77 3·94 3·13 2·31 2·88 3·21 3·56 3·33 Tm 0·48 0·55 0·59 0·49 0·37 0·48 0·46 0·56 0·49 Yb 2·91 3·67 3·78 3·06 2·49 2·94 3·15 3·66 3·27 Lu 0·43 0·54 0·59 0·47 0·40 0·44 0·45 0·53 0·49 Hf 4·19 2·77 4·61 4·70 6·34 3·85 5·69 5·27 5·42 Ta 0·59 1·02 1·05 1·38 1·00 1·16 1·37 1·42 1·41 Pb 22·1 15·6 15·7 29·8 19·7 14·9 6·70 9·00 19·0 Th 4·72 6·59 7·75 15·5 8·98 14·0 13·5 13·4 11·5 U 1·24 1·96 2·09 2·86 1·79 4·59 3·35 3·62 3·38 ∑REE 156 155 184 197 156 191 173 195 179 δEu 0·96 0·78 0·68 0·64 1·16 0·62 0·60 0·61 0·58 (La/Yb)N 6·97 5·08 6·25 10·0 9·76 10·0 8·51 7·82 8·04 Rock type Quartz monzonite Monzonite MME Sample 15TL-13 15TL-14 12TL-12 12TL-22-1 12TL-23-1 12TL-20-2 15TL-01-3 12TL-16 12TL-17 12TL-18 SiO2 65·93 63·46 59·21 59·03 58·47 58·49 59·53 53·92 52·76 54·00 TiO2 0·50 0·70 0·95 0·98 1·02 1·00 0·99 0·97 0·99 0·91 Al2O3 15·26 15·76 17·00 16·26 16·30 16·23 16·40 16·12 16·40 15·82 Fe2 O3T 3·64 5·08 6·42 6·77 6·92 7·48 7·05 8·10 8·66 8·34 MnO 0·08 0·10 0·13 0·13 0·13 0·13 0·12 0·18 0·21 0·20 MgO 0·99 1·38 1·67 2·10 2·13 2·15 2·02 3·64 3·72 3·97 CaO 2·74 3·32 4·40 4·46 4·77 4·52 4·89 6·77 6·59 6·13 Na2O 3·49 3·62 3·61 3·25 3·16 3·33 3·37 3·22 3·30 3·08 K2O 4·22 3·74 3·43 3·66 3·50 3·30 2·84 2·50 2·23 2·48 P2O5 0·16 0·25 0·35 0·34 0·36 0·36 0·36 0·26 0·26 0·26 LOI 1·20 1·30 1·69 2·05 2·56 2·48 1·45 3·35 4·07 3·40 Total 98·21 98·70 98·86 99·03 99·31 99·45 99·03 99·01 99·18 98·60 A/CNK 1·00 0·98 0·96 0·93 0·92 0·94 0·94 0·79 0·83 0·84 A/NK 1·48 1·58 1·76 1·75 1·81 1·79 1·90 2·01 2·09 2·04 Na2O+K2O 7·72 7·35 7·04 6·91 6·66 6·63 6·21 5·72 5·52 5·56 K2O/N2O 1·21 1·03 0·95 1·12 1·11 0·99 0·84 0·77 0·68 0·80 Mg# 35·0 35·0 34·0 38·1 37·9 36·3 36·3 47·1 46·0 48·5 Sc 8·59 11·37 16·3 16·4 16·4 19·9 12·4 20·8 21·0 21·7 V 39·2 57·4 78·5 101 105 141 93·1 166 191 153 Cr 4·96 7·98 9·66 15·4 16·3 4·52 16·9 12·0 11·3 54·9 Ni 4·21 6·02 5·65 9·02 9·30 7·69 14·3 11·2 10·5 26·8 Ga 18·4 20·0 21·5 21·0 20·8 20·8 19·9 18·6 20·1 18·7 Rb 163 136 120 116 109 108 85 83·8 85·5 85·1 Sr 246 304 424 384 418 396 402 413 430 380 Y 43·8 44·3 40·8 44·4 39·4 41·8 34·5 31·0 34·2 43·2 Zr 199 246 245 234 242 177 188 156 176 115 Nb 19·5 20·3 19·0 18·2 17·6 18·5 20·6 8·50 10·2 12·3 Ba 671 786 885 715 757 743 530 662 634 718 La 41·4 45·4 38·9 50·1 42·1 32·9 32·8 23·6 25·5 29·3 Ce 84 93 78·7 98·3 83·0 69·1 67·3 47·4 54·3 64·1 Pr 9·5 10·6 9·62 11·5 9·85 8·74 8·26 5·86 7·07 8·39 Nd 37·3 42·5 40·1 46·7 40·6 36·6 33·9 25·1 30·2 36·6 Sm 8·05 8·88 8·75 9·66 8·45 8·50 7·38 5·65 6·89 8·58 Eu 1·28 1·49 2·19 1·93 2·06 1·78 1·77 1·96 2·05 1·90 Gd 6·78 7·57 7·61 8·41 7·39 7·60 6·14 5·43 6·35 7·83 Tb 1·15 1·23 1·22 1·35 1·17 1·25 0·98 0·88 1·03 1·26 Dy 7·33 7·66 7·28 7·92 6·85 7·42 5·82 5·25 6·13 7·65 Ho 1·45 1·49 1·35 1·50 1·39 1·46 1·17 1·07 1·18 1·48 Er 4·12 4·19 3·81 4·15 3·67 3·94 3·32 2·96 3·30 4·06 Tm 0·64 0·64 0·58 0·62 0·54 0·59 0·52 0·44 0·48 0·59 Yb 4·16 4·18 3·68 3·95 3·59 3·78 3·28 3·00 3·05 3·97 Lu 0·62 0·63 0·53 0·57 0·51 0·59 0·50 0·43 0·44 0·58 Hf 5·72 6·57 6·12 6·00 6·06 4·61 5·08 4·08 4·53 3·48 Ta 1·50 1·37 1·17 1·12 1·07 1·05 1·19 0·58 0·59 0·85 Pb 22·8 18·8 15·4 16·7 16·0 15·7 15·8 29·5 18·6 17·2 Th 14·6 12·4 8·05 9·49 7·61 7·75 7·21 3·32 4·27 5·34 U 4·16 3·32 2·14 2·04 1·79 2·09 2·05 0·89 1·23 1·45 ∑REE 207 230 204 247 211 204 173 129 148 176 δEu 0·53 0·56 0·82 0·65 0·80 0·79 0·80 1·08 0·95 0·71 (La/Yb)N 7·14 7·79 7·58 9·09 8·41 8·14 7·19 5·64 6·00 5·30 Rock type Quartz monzonite Monzonite MME Sample 15TL-13 15TL-14 12TL-12 12TL-22-1 12TL-23-1 12TL-20-2 15TL-01-3 12TL-16 12TL-17 12TL-18 SiO2 65·93 63·46 59·21 59·03 58·47 58·49 59·53 53·92 52·76 54·00 TiO2 0·50 0·70 0·95 0·98 1·02 1·00 0·99 0·97 0·99 0·91 Al2O3 15·26 15·76 17·00 16·26 16·30 16·23 16·40 16·12 16·40 15·82 Fe2 O3T 3·64 5·08 6·42 6·77 6·92 7·48 7·05 8·10 8·66 8·34 MnO 0·08 0·10 0·13 0·13 0·13 0·13 0·12 0·18 0·21 0·20 MgO 0·99 1·38 1·67 2·10 2·13 2·15 2·02 3·64 3·72 3·97 CaO 2·74 3·32 4·40 4·46 4·77 4·52 4·89 6·77 6·59 6·13 Na2O 3·49 3·62 3·61 3·25 3·16 3·33 3·37 3·22 3·30 3·08 K2O 4·22 3·74 3·43 3·66 3·50 3·30 2·84 2·50 2·23 2·48 P2O5 0·16 0·25 0·35 0·34 0·36 0·36 0·36 0·26 0·26 0·26 LOI 1·20 1·30 1·69 2·05 2·56 2·48 1·45 3·35 4·07 3·40 Total 98·21 98·70 98·86 99·03 99·31 99·45 99·03 99·01 99·18 98·60 A/CNK 1·00 0·98 0·96 0·93 0·92 0·94 0·94 0·79 0·83 0·84 A/NK 1·48 1·58 1·76 1·75 1·81 1·79 1·90 2·01 2·09 2·04 Na2O+K2O 7·72 7·35 7·04 6·91 6·66 6·63 6·21 5·72 5·52 5·56 K2O/N2O 1·21 1·03 0·95 1·12 1·11 0·99 0·84 0·77 0·68 0·80 Mg# 35·0 35·0 34·0 38·1 37·9 36·3 36·3 47·1 46·0 48·5 Sc 8·59 11·37 16·3 16·4 16·4 19·9 12·4 20·8 21·0 21·7 V 39·2 57·4 78·5 101 105 141 93·1 166 191 153 Cr 4·96 7·98 9·66 15·4 16·3 4·52 16·9 12·0 11·3 54·9 Ni 4·21 6·02 5·65 9·02 9·30 7·69 14·3 11·2 10·5 26·8 Ga 18·4 20·0 21·5 21·0 20·8 20·8 19·9 18·6 20·1 18·7 Rb 163 136 120 116 109 108 85 83·8 85·5 85·1 Sr 246 304 424 384 418 396 402 413 430 380 Y 43·8 44·3 40·8 44·4 39·4 41·8 34·5 31·0 34·2 43·2 Zr 199 246 245 234 242 177 188 156 176 115 Nb 19·5 20·3 19·0 18·2 17·6 18·5 20·6 8·50 10·2 12·3 Ba 671 786 885 715 757 743 530 662 634 718 La 41·4 45·4 38·9 50·1 42·1 32·9 32·8 23·6 25·5 29·3 Ce 84 93 78·7 98·3 83·0 69·1 67·3 47·4 54·3 64·1 Pr 9·5 10·6 9·62 11·5 9·85 8·74 8·26 5·86 7·07 8·39 Nd 37·3 42·5 40·1 46·7 40·6 36·6 33·9 25·1 30·2 36·6 Sm 8·05 8·88 8·75 9·66 8·45 8·50 7·38 5·65 6·89 8·58 Eu 1·28 1·49 2·19 1·93 2·06 1·78 1·77 1·96 2·05 1·90 Gd 6·78 7·57 7·61 8·41 7·39 7·60 6·14 5·43 6·35 7·83 Tb 1·15 1·23 1·22 1·35 1·17 1·25 0·98 0·88 1·03 1·26 Dy 7·33 7·66 7·28 7·92 6·85 7·42 5·82 5·25 6·13 7·65 Ho 1·45 1·49 1·35 1·50 1·39 1·46 1·17 1·07 1·18 1·48 Er 4·12 4·19 3·81 4·15 3·67 3·94 3·32 2·96 3·30 4·06 Tm 0·64 0·64 0·58 0·62 0·54 0·59 0·52 0·44 0·48 0·59 Yb 4·16 4·18 3·68 3·95 3·59 3·78 3·28 3·00 3·05 3·97 Lu 0·62 0·63 0·53 0·57 0·51 0·59 0·50 0·43 0·44 0·58 Hf 5·72 6·57 6·12 6·00 6·06 4·61 5·08 4·08 4·53 3·48 Ta 1·50 1·37 1·17 1·12 1·07 1·05 1·19 0·58 0·59 0·85 Pb 22·8 18·8 15·4 16·7 16·0 15·7 15·8 29·5 18·6 17·2 Th 14·6 12·4 8·05 9·49 7·61 7·75 7·21 3·32 4·27 5·34 U 4·16 3·32 2·14 2·04 1·79 2·09 2·05 0·89 1·23 1·45 ∑REE 207 230 204 247 211 204 173 129 148 176 δEu 0·53 0·56 0·82 0·65 0·80 0·79 0·80 1·08 0·95 0·71 (La/Yb)N 7·14 7·79 7·58 9·09 8·41 8·14 7·19 5·64 6·00 5·30 LOI, loss of ignition; A/NK, molar Al2O3/(Na2O + K2O); A/CNK, molar Al2O3/(CaO + Na2O + K2O); Mg# = 100*molar Mg/(Mg + Fe). Fig. 4. View largeDownload slide Chemical classification of rocks from the Tonglu granitoids. (a) Total alkalis vs silica (TAS) diagram (Middlemost, 1994); (b) A/NK vs A/CNK diagram (Chappell & White, 1974); (c) SiO2 vs AR diagram (Wright, 1969); (d) K2O vs SiO2 diagram (Peccerillo & Taylor, 1976). Fig. 4. View largeDownload slide Chemical classification of rocks from the Tonglu granitoids. (a) Total alkalis vs silica (TAS) diagram (Middlemost, 1994); (b) A/NK vs A/CNK diagram (Chappell & White, 1974); (c) SiO2 vs AR diagram (Wright, 1969); (d) K2O vs SiO2 diagram (Peccerillo & Taylor, 1976). All the granitoids are characterized by enrichments in light rare earth elements (LREE) with negative Eu anomalies (δEu = EuN/(SmN*GdN)1/2) (δEu = 0·51–0·82) (Fig. 5a). Their δEu values decrease with increasing SiO2 content (0·70–0·78 for the monzodiorites, 0·65–0·82 for the monzonites and 0·51–0·59 for the quartz monzonites, respectively). In primitive mantle-normalized trace element patterns (Fig. 5b), they show positive anomalies in large ion lithophile elements (LILE, such as Rb, K and Pb), and negative anomalies in high field strength elements (HFSE, such as Nb, Ta and Ti). Compared with the monzonites, the monzodiorites have stronger negative anomalies in Zr, Hf, Nb and Ta, while the quartz monzonites have stronger positive anomalies in Th and U. Furthermore, the total REE contents of the monzodiorites (ΣREE = 147–170 ppm) are lower than the monzonites and quartz monzonites (ΣREE = 173–247 ppm) Fig. 5. View largeDownload slide Chondrite-normalized REE patterns (a, c, e) and primitive mantle mormalized trace element patterns (b, d, f) for the Tonglu granitoids, MME and CRX. Chondrite and primitive mantle values are from Sun & McDonough (1989). Fig. 5. View largeDownload slide Chondrite-normalized REE patterns (a, c, e) and primitive mantle mormalized trace element patterns (b, d, f) for the Tonglu granitoids, MME and CRX. Chondrite and primitive mantle values are from Sun & McDonough (1989). Mafic microgranular enclaves The MME from the Tonglu granitoids have SiO2 contents ranging from 52·8 wt % to 58·0 wt % with relatively high alkali contents (5·52–6·56 wt %), and plot in the field of high-K calc-alkaline series (Fig. 4). They have relatively higher MgO (2·51–3·97 wt %), Fe2 O3T (7·36–8·08 wt %), CaO (4·68–5·94 wt %) contents, but lower K2O contents (2·23–3·02 wt %) than the host-rocks. All the MME are characterized by LREE-enriched REE patterns (Fig. 5c) and Eu anomalies varying from weak positive to moderate negative (δEu = 0·68–1·08). They have similar trace element patterns to their host-rocks, which are characterized by enrichments in K, Rb and Pb, and depletions in Nb, Ta and Ti (Fig. 5d). However, they have lower total REE contents (ΣREE = 129–184 ppm) and HFSE contents than the host granitoids (ΣREE = 173–247 ppm). Country-rock xenoliths Compared with the MME, the CRX have relatively high SiO2 contents ranging from 65·3 wt % to 67·4 wt %, with relatively low alkali contents (1·0 – 4·7 wt %). They are enriched in LREE with moderate negative Eu anomalies (δEu = 0·58–0·61) (Fig. 5e). In primitive mantle-normalized trace element diagrams, they are characterized by depletions in Rb, Ba and K, and enrichments in Th, U and Pb (Fig. 5d and f). In contrast, except for Rb, Ba and K, the dark rims of the CRX have similar REE and trace element patterns to the fresh cores. The dark rims are characterized by enrichments in Rb, Ba, K compared with the fresh cores (Fig. 5f). Whole rock Sr–Nd isotopic compositions Whole rock Sr–Nd isotopic compositions are listed in Table 3. Initial Sr–Nd isotopic compositions were calculated at 130 Ma (the zircon U–Pb age obtained in this study). The monzonites and quartz monzonites have similar 87Sr/86Sri (0·7080 to 0·7085) and εNd(t) values (-5·3 to -5·6), with two-stage Mesoproterozoic Nd model ages. In contrast, the monzodiorites are characterized by relatively low 87Sr/86Sri ratios (0·7074) and high εNd(t) values (-4·7). The MME (87Sr/86Sri = 0·7082) have similar initial 87Sr/86Sr to their host-rocks (0·7085). They have εNd(t) values of -4·7, which are the same as the monzodiorites (-4·7), but slightly higher than the host-rocks (-5·3 to -5·6). However, the CRX have completely different initial 87Sr/86Sr ratios (0·7129) and εNd(t) (-10·2) values from their host-rocks. Zircon U–Pb geochronology and Hf isotopic composition Zircon U–Pb geochronology Representative CL images of zircons selected for U–Pb dating are shown in Fig. 6. Zircon U–Pb ages are summarized in Supplementary Data Table S1; supplementary data are available for downloading at http://www.petrology.oxfordjournals.org and shown in Fig. 7. Fig. 6. View largeDownload slide Representative cathodoluminescence (CL) images of selected zircons from the Tonglu granitoids and MME. Fig. 6. View largeDownload slide Representative cathodoluminescence (CL) images of selected zircons from the Tonglu granitoids and MME. Fig. 7. View largeDownload slide Zircon U–Pb Concordia diagrams for samples from the Tonglu granitoids and MME. 12TL-18 is a MME sample; 12TL-26 is a monzodiorite; 14ZJ54 is a monzonite; 12TL-06 is a quartz monzonite. Fig. 7. View largeDownload slide Zircon U–Pb Concordia diagrams for samples from the Tonglu granitoids and MME. 12TL-18 is a MME sample; 12TL-26 is a monzodiorite; 14ZJ54 is a monzonite; 12TL-06 is a quartz monzonite. Zircons from the monzodiorites (12TL-26) are euhedral to subhedral, transparent, ranging mostly from 50 to 200 μm in length, and have length to width ratios between 1:1 and 4:1. Their regular oscillatory magmatic zoning and striped absorption (Fig. 6) and high Th/U ratios (0·7– 1·1) indicate a magmatic origin. No inherited core were observed. U–Pb analyses plot in a group on the Concordia curve and yield a weighted mean 206Pb/238U age of 130·0 ± 1·3 Ma (MSWD = 1·9, 2σ, n = 32) (Fig. 7). This age is interpreted as the best estimate of the crystallization age for the monzodiorite. Zircons from the monzonites (14TL-54) are euhedral to subhedral, 50 to 400 μm in length with a length to width ratio of about 1:1 to 7:1. Their regular oscillatory magmatic zoning and striped absorption (Fig. 6) and high Th/U ratios (0·22 to 0·73) indicate a magmatic origin. All the analyses have indistinguishable U–Pb isotopic compositions within analytical uncertainty, and correspond to a weighted mean 206Pb/238U age of 129·4 ± 1·4 Ma (MSWD = 1·2, 2σ, n = 33) (Fig. 7). This age is interpreted as the best estimate of the crystallization age for the monzonites. Zircons from the quartz monzonites (12TL-06) are euhedral to subhedral, transparent, ranging mostly from 50 to 300 μm in length, and have length to width ratios between 1:1 and 5:1. Their regular oscillatory magmatic zoning and striped absorption (Fig. 6) and high Th/U ratios (0·29–0·95) indicate a magmatic origin. The analyses are concordant and correspond to a weighted mean 206Pb/238U age of 129·4 ± 1·4 Ma (MSWD = 2·6, 2σ, n = 21) (Fig. 7). This age is interpreted as the best estimate of the crystallization age for the quartz monzonites. Zircons from the MME (12TL-18) are relatively small, mostly between 50 and 150 μm. Their regular oscillatory magmatic zoning and striped absorption (Fig. 6) and high Th/U ratios (0·49–1·33) indicate a magmatic origin. U–Pb isotopic analyses plot in a group on the Concordia curve and yield a weighted mean 206Pb/238U age of 131 ± 1 Ma (MSWD = 0·86, 2σ, n = 20) (Fig. 7). This age is interpreted as the best estimate of the crystallization age of the MME. Zircon Hf isotopic compositions In situ Hf isotopic compositions of zircons are shown in Supplementary Data Table S2. For the calculation of εHf(t) and TDM2 values, the in situ zircon U–Pb ages of each zircon were used. Zircons from the quartz monzonites have initial 176Hf/177Hf ratios from 0·282497 to 0·282626, εHf(t) values from -2·4 to -7·0 and TDM2 values from 1·19 to 1·44 Ga. Zircons from the monzonites have initial 176Hf/177Hf ratios from 0·282462–0·282649, with εHf(t) values ranging from -1·7 to -8·1 and TDM2 values from 1·15 Ga to 1·51 Ga. Zircons from the monzodiorites have relatively homogeneous Hf isotopic compositions with 176Hf/177Hf ratios from 0·282583 to 0·282629, εHf(t) values from -2·3 to -3·9 and TDM2 values from 1·14 Ga to 1·27 Ga. Zircons from the MME display different Hf isotopic compositions compared with their host monzonites (Fig. 8). They are characterized by relatively homogeneous zircon Hf isotopic compositions (176Hf/177Hf ratios = 0·282561–0·282677), with εHf(t) values (-0·7 to -4·0) and a maximum peak at -1. Calculated two-stage TDM2 values vary from 1·09 Ga to 1·28 Ga. Fig. 8. View largeDownload slide Relative probability plots for εHf(t) values of zircons from the host granitoids and MME. Data for the host granitoid are from 14ZJ54 in this study and HC01 by Wong et al. (2011); data for MME are from 12TL-18 in this study. Fig. 8. View largeDownload slide Relative probability plots for εHf(t) values of zircons from the host granitoids and MME. Data for the host granitoid are from 14ZJ54 in this study and HC01 by Wong et al. (2011); data for MME are from 12TL-18 in this study. Chemical and Sr isotopic compositions of plagioclase The 87Sr/86Sr compositions of plagioclase vary in a wide range from 0·7073–0·7137 (Tables 4–6; Fig. 9). Due to their high Sr contents, but low Rb/Sr ratios, and the relative young age, the measured 87Sr/86Sr for plagioclases show no meaningful difference from the calculated initial 87Sr/86Sr, considering the analytical uncertainty. 87Sr/86Sr correlates positively with some major and trace elements (e.g. FeO, Sr, Pb and LREE) and plagioclase An value (Tables 4 and 5; Fig. 9). Based on the rim-core-rim variation of 87Sr/86Sr, four types of plagioclase were identified in the Tonglu granitoids. Table 3: Whole-rock Sr-Nd isotopic compositions of the Tonglu granitoids, MME and CRX Sample Lithology 87Rb/86Sr 87Sr/86Sr 2σ 87Sr/86Sri 147Sm/144Nd 143Nd/144Nd 2σ εNd(t) tDM2(Ga) 12TL-03 Monzodiorite 0·32 0·708021 12 0·707437 0·135 0·512344 4 −4·7 1·13 12TL-05 Quartz monzonite 1·85 0·711460 12 0·708044 0·129 0·512296 6 −5·6 1·19 12TL-22-1 Monzonite 0·88 0·710157 12 0·708537 0·125 0·512303 10 −5·3 1·17 12TL-18 MME 0·65 0·709481 16 0·708285 0·142 0·512352 6 −4·7 1·13 14ZJ58 CRX 1·00 0·714752 12 0·712905 0·123 0·512052 8 −10·2 1·51 Sample Lithology 87Rb/86Sr 87Sr/86Sr 2σ 87Sr/86Sri 147Sm/144Nd 143Nd/144Nd 2σ εNd(t) tDM2(Ga) 12TL-03 Monzodiorite 0·32 0·708021 12 0·707437 0·135 0·512344 4 −4·7 1·13 12TL-05 Quartz monzonite 1·85 0·711460 12 0·708044 0·129 0·512296 6 −5·6 1·19 12TL-22-1 Monzonite 0·88 0·710157 12 0·708537 0·125 0·512303 10 −5·3 1·17 12TL-18 MME 0·65 0·709481 16 0·708285 0·142 0·512352 6 −4·7 1·13 14ZJ58 CRX 1·00 0·714752 12 0·712905 0·123 0·512052 8 −10·2 1·51 εNd(t) values are calculated based on the crystallization age of zircon and a 147Sm decay constant of 6·54 x 10–12. The 143Nd/144Nd and 147Sm/144Nd ratios of chondrite and depleted mantle at the present day are 0·512638 and 0·1967, 0·513151 and 0·2136, respectively (Miller & O'Nions, 1985). Table 3: Whole-rock Sr-Nd isotopic compositions of the Tonglu granitoids, MME and CRX Sample Lithology 87Rb/86Sr 87Sr/86Sr 2σ 87Sr/86Sri 147Sm/144Nd 143Nd/144Nd 2σ εNd(t) tDM2(Ga) 12TL-03 Monzodiorite 0·32 0·708021 12 0·707437 0·135 0·512344 4 −4·7 1·13 12TL-05 Quartz monzonite 1·85 0·711460 12 0·708044 0·129 0·512296 6 −5·6 1·19 12TL-22-1 Monzonite 0·88 0·710157 12 0·708537 0·125 0·512303 10 −5·3 1·17 12TL-18 MME 0·65 0·709481 16 0·708285 0·142 0·512352 6 −4·7 1·13 14ZJ58 CRX 1·00 0·714752 12 0·712905 0·123 0·512052 8 −10·2 1·51 Sample Lithology 87Rb/86Sr 87Sr/86Sr 2σ 87Sr/86Sri 147Sm/144Nd 143Nd/144Nd 2σ εNd(t) tDM2(Ga) 12TL-03 Monzodiorite 0·32 0·708021 12 0·707437 0·135 0·512344 4 −4·7 1·13 12TL-05 Quartz monzonite 1·85 0·711460 12 0·708044 0·129 0·512296 6 −5·6 1·19 12TL-22-1 Monzonite 0·88 0·710157 12 0·708537 0·125 0·512303 10 −5·3 1·17 12TL-18 MME 0·65 0·709481 16 0·708285 0·142 0·512352 6 −4·7 1·13 14ZJ58 CRX 1·00 0·714752 12 0·712905 0·123 0·512052 8 −10·2 1·51 εNd(t) values are calculated based on the crystallization age of zircon and a 147Sm decay constant of 6·54 x 10–12. The 143Nd/144Nd and 147Sm/144Nd ratios of chondrite and depleted mantle at the present day are 0·512638 and 0·1967, 0·513151 and 0·2136, respectively (Miller & O'Nions, 1985). Table 4: In situ Sr isotopic compositions of plagioclase in the Tonglu granitoids Sample· 87Sr/86Sr 1σ 87Rb/86Sr 1σ 87Sr/86Sr130 1σ 15TL-08-4-02-01 0·70817 0·00007 0·04529 0·00014 0·70808 0·00007 15TL-08-4-02-02 0·70844 0·00007 0·04593 0·00030 0·70836 0·00007 15TL-08-4-02-03 0·70906 0·00006 0·00960 0·00009 0·70904 0·00006 15TL-08-4-02-04 0·70858 0·00006 0·04563 0·00106 0·70850 0·00006 15TL-08-4-02-05 0·70917 0·00008 0·12204 0·00402 0·70894 0·00008 15TL-08-4-02-06 0·70891 0·00008 0·02162 0·00035 0·70887 0·00008 15TL-08-4-02-07 0·70913 0·00008 0·02302 0·00011 0·70909 0·00008 15TL-08-4-02-10 0·70850 0·00007 0·11909 0·00193 0·70828 0·00007 15TL-08-4-02-11 0·70829 0·00007 0·09807 0·00121 0·70811 0·00007 15TL-08-4-02-12 0·70880 0·00015 0·14320 0·00108 0·70853 0·00015 15TL-08-01-01 0·71171 0·00009 0·03288 0·00058 0·71165 0·00009 15TL-08-01-02 0·70775 0·00005 0·00992 0·00009 0·70773 0·00005 15TL-08-01-03 0·70765 0·00005 0·03137 0·00042 0·70759 0·00005 15TL-08-01-04 0·70766 0·00006 0·03137 0·00039 0·70761 0·00006 15TL-08-01-05 0·70822 0·00007 0·03559 0·00029 0·70815 0·00007 15TL-08-01-06 0·70860 0·00010 0·03228 0·00060 0·70854 0·00010 15TL-08-01-07 0·70861 0·00010 0·09502 0·00081 0·70843 0·00010 15TL-08-01-08 0·70756 0·00005 0·01839 0·00028 0·70752 0·00005 15TL-08-01-09 0·70798 0·00004 0·02329 0·00101 0·70794 0·00004 15TL-08-01-10 0·71117 0·00008 0·02512 0·00018 0·71112 0·00008 15TL-09-1-02-01 0·70973 0·0001 0·05819 0·00067 0·70962 0·00013 15TL-09-1-02-02 0·70838 0·0001 0·01500 0·00023 0·70835 0·00010 15TL-09-1-02-04 0·70857 0·0001 0·02764 0·00034 0·70852 0·00013 15TL-09-1-02-05 0·71115 0·0001 0·04780 0·00019 0·71106 0·00015 14ZJ59-1-1 0·70869 0·00005 0·00354 0·00001 0·70868 0·00005 14ZJ59-1-2 0·70851 0·00004 0·00304 0·00002 0·70850 0·00004 14ZJ59-1-3 0·70879 0·00005 0·00344 0·00001 0·70878 0·00005 14ZJ59-1-4 0·70864 0·00006 0·01486 0·00020 0·70861 0·00006 14ZJ59-1-5 0·70849 0·00008 0·01321 0·00010 0·70847 0·00008 12TL-03-1 0·70743 0·00005 0·02912 0·00104 0·70738 0·00005 12TL-03-2 0·70741 0·00005 0·03174 0·00054 0·70735 0·00005 12TL-03-3 0·70734 0·00006 0·11203 0·00293 0·70713 0·00006 15TL-12-08-01 0·70730 0·00004 0·04663 0·00279 0·70721 0·00004 15TL-12-08-02 0·70732 0·00005 0·02408 0·00057 0·70728 0·00005 15TL-12-09-01 0·70805 0·00005 0·02979 0·00018 0·70800 0·00005 15TL-12-09-02 0·70800 0·00007 0·17169 0·00499 0·70768 0·00007 12TL-17-1 0·70688 0·00007 0·10180 0·00259 0·70669 0·00007 12TL-17-2 0·70822 0·00007 0·02111 0·00073 0·70818 0·00007 12TL-17-3 0·70882 0·00009 0·00656 0·00005 0·70881 0·00009 14ZJ58-2-1 0·71327 0·0001 0·15763 0·00130 0·71297 0·00014 14ZJ58-2-2 0·71344 0·0002 0·04994 0·00065 0·71335 0·00020 14ZJ58-1-1 0·71369 0·0001 0·02495 0·00137 0·71364 0·00014 Sample· 87Sr/86Sr 1σ 87Rb/86Sr 1σ 87Sr/86Sr130 1σ 15TL-08-4-02-01 0·70817 0·00007 0·04529 0·00014 0·70808 0·00007 15TL-08-4-02-02 0·70844 0·00007 0·04593 0·00030 0·70836 0·00007 15TL-08-4-02-03 0·70906 0·00006 0·00960 0·00009 0·70904 0·00006 15TL-08-4-02-04 0·70858 0·00006 0·04563 0·00106 0·70850 0·00006 15TL-08-4-02-05 0·70917 0·00008 0·12204 0·00402 0·70894 0·00008 15TL-08-4-02-06 0·70891 0·00008 0·02162 0·00035 0·70887 0·00008 15TL-08-4-02-07 0·70913 0·00008 0·02302 0·00011 0·70909 0·00008 15TL-08-4-02-10 0·70850 0·00007 0·11909 0·00193 0·70828 0·00007 15TL-08-4-02-11 0·70829 0·00007 0·09807 0·00121 0·70811 0·00007 15TL-08-4-02-12 0·70880 0·00015 0·14320 0·00108 0·70853 0·00015 15TL-08-01-01 0·71171 0·00009 0·03288 0·00058 0·71165 0·00009 15TL-08-01-02 0·70775 0·00005 0·00992 0·00009 0·70773 0·00005 15TL-08-01-03 0·70765 0·00005 0·03137 0·00042 0·70759 0·00005 15TL-08-01-04 0·70766 0·00006 0·03137 0·00039 0·70761 0·00006 15TL-08-01-05 0·70822 0·00007 0·03559 0·00029 0·70815 0·00007 15TL-08-01-06 0·70860 0·00010 0·03228 0·00060 0·70854 0·00010 15TL-08-01-07 0·70861 0·00010 0·09502 0·00081 0·70843 0·00010 15TL-08-01-08 0·70756 0·00005 0·01839 0·00028 0·70752 0·00005 15TL-08-01-09 0·70798 0·00004 0·02329 0·00101 0·70794 0·00004 15TL-08-01-10 0·71117 0·00008 0·02512 0·00018 0·71112 0·00008 15TL-09-1-02-01 0·70973 0·0001 0·05819 0·00067 0·70962 0·00013 15TL-09-1-02-02 0·70838 0·0001 0·01500 0·00023 0·70835 0·00010 15TL-09-1-02-04 0·70857 0·0001 0·02764 0·00034 0·70852 0·00013 15TL-09-1-02-05 0·71115 0·0001 0·04780 0·00019 0·71106 0·00015 14ZJ59-1-1 0·70869 0·00005 0·00354 0·00001 0·70868 0·00005 14ZJ59-1-2 0·70851 0·00004 0·00304 0·00002 0·70850 0·00004 14ZJ59-1-3 0·70879 0·00005 0·00344 0·00001 0·70878 0·00005 14ZJ59-1-4 0·70864 0·00006 0·01486 0·00020 0·70861 0·00006 14ZJ59-1-5 0·70849 0·00008 0·01321 0·00010 0·70847 0·00008 12TL-03-1 0·70743 0·00005 0·02912 0·00104 0·70738 0·00005 12TL-03-2 0·70741 0·00005 0·03174 0·00054 0·70735 0·00005 12TL-03-3 0·70734 0·00006 0·11203 0·00293 0·70713 0·00006 15TL-12-08-01 0·70730 0·00004 0·04663 0·00279 0·70721 0·00004 15TL-12-08-02 0·70732 0·00005 0·02408 0·00057 0·70728 0·00005 15TL-12-09-01 0·70805 0·00005 0·02979 0·00018 0·70800 0·00005 15TL-12-09-02 0·70800 0·00007 0·17169 0·00499 0·70768 0·00007 12TL-17-1 0·70688 0·00007 0·10180 0·00259 0·70669 0·00007 12TL-17-2 0·70822 0·00007 0·02111 0·00073 0·70818 0·00007 12TL-17-3 0·70882 0·00009 0·00656 0·00005 0·70881 0·00009 14ZJ58-2-1 0·71327 0·0001 0·15763 0·00130 0·71297 0·00014 14ZJ58-2-2 0·71344 0·0002 0·04994 0·00065 0·71335 0·00020 14ZJ58-1-1 0·71369 0·0001 0·02495 0·00137 0·71364 0·00014 Table 4: In situ Sr isotopic compositions of plagioclase in the Tonglu granitoids Sample· 87Sr/86Sr 1σ 87Rb/86Sr 1σ 87Sr/86Sr130 1σ 15TL-08-4-02-01 0·70817 0·00007 0·04529 0·00014 0·70808 0·00007 15TL-08-4-02-02 0·70844 0·00007 0·04593 0·00030 0·70836 0·00007 15TL-08-4-02-03 0·70906 0·00006 0·00960 0·00009 0·70904 0·00006 15TL-08-4-02-04 0·70858 0·00006 0·04563 0·00106 0·70850 0·00006 15TL-08-4-02-05 0·70917 0·00008 0·12204 0·00402 0·70894 0·00008 15TL-08-4-02-06 0·70891 0·00008 0·02162 0·00035 0·70887 0·00008 15TL-08-4-02-07 0·70913 0·00008 0·02302 0·00011 0·70909 0·00008 15TL-08-4-02-10 0·70850 0·00007 0·11909 0·00193 0·70828 0·00007 15TL-08-4-02-11 0·70829 0·00007 0·09807 0·00121 0·70811 0·00007 15TL-08-4-02-12 0·70880 0·00015 0·14320 0·00108 0·70853 0·00015 15TL-08-01-01 0·71171 0·00009 0·03288 0·00058 0·71165 0·00009 15TL-08-01-02 0·70775 0·00005 0·00992 0·00009 0·70773 0·00005 15TL-08-01-03 0·70765 0·00005 0·03137 0·00042 0·70759 0·00005 15TL-08-01-04 0·70766 0·00006 0·03137 0·00039 0·70761 0·00006 15TL-08-01-05 0·70822 0·00007 0·03559 0·00029 0·70815 0·00007 15TL-08-01-06 0·70860 0·00010 0·03228 0·00060 0·70854 0·00010 15TL-08-01-07 0·70861 0·00010 0·09502 0·00081 0·70843 0·00010 15TL-08-01-08 0·70756 0·00005 0·01839 0·00028 0·70752 0·00005 15TL-08-01-09 0·70798 0·00004 0·02329 0·00101 0·70794 0·00004 15TL-08-01-10 0·71117 0·00008 0·02512 0·00018 0·71112 0·00008 15TL-09-1-02-01 0·70973 0·0001 0·05819 0·00067 0·70962 0·00013 15TL-09-1-02-02 0·70838 0·0001 0·01500 0·00023 0·70835 0·00010 15TL-09-1-02-04 0·70857 0·0001 0·02764 0·00034 0·70852 0·00013 15TL-09-1-02-05 0·71115 0·0001 0·04780 0·00019 0·71106 0·00015 14ZJ59-1-1 0·70869 0·00005 0·00354 0·00001 0·70868 0·00005 14ZJ59-1-2 0·70851 0·00004 0·00304 0·00002 0·70850 0·00004 14ZJ59-1-3 0·70879 0·00005 0·00344 0·00001 0·70878 0·00005 14ZJ59-1-4 0·70864 0·00006 0·01486 0·00020 0·70861 0·00006 14ZJ59-1-5 0·70849 0·00008 0·01321 0·00010 0·70847 0·00008 12TL-03-1 0·70743 0·00005 0·02912 0·00104 0·70738 0·00005 12TL-03-2 0·70741 0·00005 0·03174 0·00054 0·70735 0·00005 12TL-03-3 0·70734 0·00006 0·11203 0·00293 0·70713 0·00006 15TL-12-08-01 0·70730 0·00004 0·04663 0·00279 0·70721 0·00004 15TL-12-08-02 0·70732 0·00005 0·02408 0·00057 0·70728 0·00005 15TL-12-09-01 0·70805 0·00005 0·02979 0·00018 0·70800 0·00005 15TL-12-09-02 0·70800 0·00007 0·17169 0·00499 0·70768 0·00007 12TL-17-1 0·70688 0·00007 0·10180 0·00259 0·70669 0·00007 12TL-17-2 0·70822 0·00007 0·02111 0·00073 0·70818 0·00007 12TL-17-3 0·70882 0·00009 0·00656 0·00005 0·70881 0·00009 14ZJ58-2-1 0·71327 0·0001 0·15763 0·00130 0·71297 0·00014 14ZJ58-2-2 0·71344 0·0002 0·04994 0·00065 0·71335 0·00020 14ZJ58-1-1 0·71369 0·0001 0·02495 0·00137 0·71364 0·00014 Sample· 87Sr/86Sr 1σ 87Rb/86Sr 1σ 87Sr/86Sr130 1σ 15TL-08-4-02-01 0·70817 0·00007 0·04529 0·00014 0·70808 0·00007 15TL-08-4-02-02 0·70844 0·00007 0·04593 0·00030 0·70836 0·00007 15TL-08-4-02-03 0·70906 0·00006 0·00960 0·00009 0·70904 0·00006 15TL-08-4-02-04 0·70858 0·00006 0·04563 0·00106 0·70850 0·00006 15TL-08-4-02-05 0·70917 0·00008 0·12204 0·00402 0·70894 0·00008 15TL-08-4-02-06 0·70891 0·00008 0·02162 0·00035 0·70887 0·00008 15TL-08-4-02-07 0·70913 0·00008 0·02302 0·00011 0·70909 0·00008 15TL-08-4-02-10 0·70850 0·00007 0·11909 0·00193 0·70828 0·00007 15TL-08-4-02-11 0·70829 0·00007 0·09807 0·00121 0·70811 0·00007 15TL-08-4-02-12 0·70880 0·00015 0·14320 0·00108 0·70853 0·00015 15TL-08-01-01 0·71171 0·00009 0·03288 0·00058 0·71165 0·00009 15TL-08-01-02 0·70775 0·00005 0·00992 0·00009 0·70773 0·00005 15TL-08-01-03 0·70765 0·00005 0·03137 0·00042 0·70759 0·00005 15TL-08-01-04 0·70766 0·00006 0·03137 0·00039 0·70761 0·00006 15TL-08-01-05 0·70822 0·00007 0·03559 0·00029 0·70815 0·00007 15TL-08-01-06 0·70860 0·00010 0·03228 0·00060 0·70854 0·00010 15TL-08-01-07 0·70861 0·00010 0·09502 0·00081 0·70843 0·00010 15TL-08-01-08 0·70756 0·00005 0·01839 0·00028 0·70752 0·00005 15TL-08-01-09 0·70798 0·00004 0·02329 0·00101 0·70794 0·00004 15TL-08-01-10 0·71117 0·00008 0·02512 0·00018 0·71112 0·00008 15TL-09-1-02-01 0·70973 0·0001 0·05819 0·00067 0·70962 0·00013 15TL-09-1-02-02 0·70838 0·0001 0·01500 0·00023 0·70835 0·00010 15TL-09-1-02-04 0·70857 0·0001 0·02764 0·00034 0·70852 0·00013 15TL-09-1-02-05 0·71115 0·0001 0·04780 0·00019 0·71106 0·00015 14ZJ59-1-1 0·70869 0·00005 0·00354 0·00001 0·70868 0·00005 14ZJ59-1-2 0·70851 0·00004 0·00304 0·00002 0·70850 0·00004 14ZJ59-1-3 0·70879 0·00005 0·00344 0·00001 0·70878 0·00005 14ZJ59-1-4 0·70864 0·00006 0·01486 0·00020 0·70861 0·00006 14ZJ59-1-5 0·70849 0·00008 0·01321 0·00010 0·70847 0·00008 12TL-03-1 0·70743 0·00005 0·02912 0·00104 0·70738 0·00005 12TL-03-2 0·70741 0·00005 0·03174 0·00054 0·70735 0·00005 12TL-03-3 0·70734 0·00006 0·11203 0·00293 0·70713 0·00006 15TL-12-08-01 0·70730 0·00004 0·04663 0·00279 0·70721 0·00004 15TL-12-08-02 0·70732 0·00005 0·02408 0·00057 0·70728 0·00005 15TL-12-09-01 0·70805 0·00005 0·02979 0·00018 0·70800 0·00005 15TL-12-09-02 0·70800 0·00007 0·17169 0·00499 0·70768 0·00007 12TL-17-1 0·70688 0·00007 0·10180 0·00259 0·70669 0·00007 12TL-17-2 0·70822 0·00007 0·02111 0·00073 0·70818 0·00007 12TL-17-3 0·70882 0·00009 0·00656 0·00005 0·70881 0·00009 14ZJ58-2-1 0·71327 0·0001 0·15763 0·00130 0·71297 0·00014 14ZJ58-2-2 0·71344 0·0002 0·04994 0·00065 0·71335 0·00020 14ZJ58-1-1 0·71369 0·0001 0·02495 0·00137 0·71364 0·00014 Fig. 9. View largeDownload slide View largeDownload slide Variations in elemental and Sr isotopic compositions of plagioclases in the Tonglu granitoids. Fig. 9. View largeDownload slide View largeDownload slide Variations in elemental and Sr isotopic compositions of plagioclases in the Tonglu granitoids. Type I plagioclase is widely distributed in all rock types of the Tonglu granitoids. They are homogeneous in terms of 87Sr/86Sr, considering the analytical uncertainty, and have normally zoned chemical compositions, i.e. An content decreases from the core to the rim (Fig. 9; Table 5). Type I plagioclase in monzonite (14ZJ59–1) is characterized by relatively radiogenic Sr (0·7085–0·7088) with variable An contents (An30–An50). Type I plagioclases in the monzodiorite (12TL-03–2) have lower 87Sr/86Sr (0·7073–0·7074), but higher An contents (An68–An49) (Tables 4 and 5). Type II, III and IV plagioclases are found only in the quartz monzonite. Type II plagioclase is characterized by an n-shaped pattern in terms of 87Sr/86Sr decreasing from core to rim, and shows reversely zoned chemical compositions, i.e. An value increases abruptly from An30 to An60 from core to mantle and then decreases from mantle to rim (Table 5; Fig. 9). An content and FeO content of the type II plagioclase varies coherently, FeO content increases from 0·23 to 0·70 wt % from core to mantle and then decreases from mantle to rim (Table 6). The low-An core has more radiogenic Sr (87Sr/86Sr = 0·7089–0·7092) than the mantle and rim (87Sr/86Sr = 0·7081–0·7085). Type III plagioclase sampled close to the boundary of a CRX, characterized by a ‘u’ shape in terms of 87Sr/86Sr increasing from core to rim, and shows normally zoned chemical compositions (Fig. 9). The high-An–FeO core (∼An60; FeO = 0·22−0·38 wt %) has a constant Sr isotope composition of 0·7084–0·7086, whereas the low-An–FeO rim (∼An30; FeO = 0·18–0·20 wt %) exhibits significantly higher 87Sr/86Sr of 0·7097–0·7112 (Table 6; Fig. 9). The Type III plagioclase is found in the quartz monzonite in contact with a CRX (Fig. 9). Type IV plagioclase is characterized by a ‘w’ shape in terms of 87Sr/86Sr variation from core to rim and shows reversely zoned chemical compositions; it looks like a combination of type II and type III plagioclase (Fig. 9). 87Sr/86Sr gradually decreases from the low-An core (87Sr/86Sr = 0·7082–0·7086; An24–An33) to the high-An mantle (87Sr/86Sr = 0·7075–0·7079; An34–An51) (Fig. 9), and then increases significantly in the low-An rim (87Sr/86Sr = 0·7112–0·7117; An30–An35) (Fig. 9). The FeO content of the type IV plagioclase increases from 0·.17 to 0·48 wt % from core to mantle and then decreases from mantle to rim; FeO varies coherently with An content (Table 6). Plagioclases from the MME are small grains with variable An contents (31–50) and 87Sr/86Sr (0·7073–0·7085) (Tables 4 and 5). Small plagioclase grains in a fine vein intruded into the dark rim of a CRX have the highest Sr isotopic ratios (87Sr/86Sr = 0·7135–0·7137) (Table 4). Their An contents vary from An34–An39. They have relative low Sr (359–417 ppm) and high Pb contents (59·6–66·9 ppm) (Table 5). Table 5: In situ major and trace element compositions of plagioclase in the Tonglu granitoids Sample 15TL-08-01 15TL-08-4-02 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 11 12 Major element (wt %) SiO2 58·8 55·1 56·1 56·9 60·0 61·1 59·1 58·2 56·6 59·4 60·8 60·3 53·9 54·0 59·7 59·4 59·4 59·9 59·4 52·8 53·9 60·8 TiO2 0·01 0·02 0·03 0·02 0·01 0·01 0·01 0·01 0·04 0·01 0·02 0·01 0·04 0·01 0·01 0·01 0·01 0·01 0·01 0·06 0·03 0·01 Al2O3 25·7 27·9 27·4 27·1 24·9 24·2 25·3 26·2 27·3 25·3 24·3 24·5 28·7 28·8 25·0 25·1 25·1 24·7 25·1 29·3 28·8 24·2 FeO 0·091 0·48 0·20 0·16 0·17 0·21 0·26 0·19 0·20 0·19 0·30 0·23 0·46 0·37 0·24 0·24 0·23 0·23 0·25 0·70 0·37 0·22 MnO 0·00 0·01 0·01 0·01 0·00 0·00 0·00 0·00 0·01 0·00 0·00 0·00 0·01 0·01 0·00 0·00 0·00 0·00 0·00 0·01 0·01 0·00 MgO 0·01 0·05 0·02 0·02 0·01 0·01 0·02 0·02 0·01 0·01 0·02 0·01 0·03 0·06 0·01 0·02 0·02 0·01 0·02 0·02 0·02 0·02 CaO 7·41 10·4 9·50 8·81 6·25 5·30 7·05 7·38 8·74 6·44 5·75 6·42 11·4 11·3 6·69 7·17 7·05 6·82 6·82 12·2 11·4 6·07 Na2O 7·05 5·32 5·92 6·23 7·85 8·41 7·62 6·95 6·36 7·42 7·88 7·36 4·93 4·93 7·57 7·22 7·26 7·27 7·25 4·26 4·53 8·03 K2O 0·74 0·45 0·53 0·58 0·54 0·50 0·48 0·85 0·50 1·02 0·82 0·93 0·33 0·35 0·61 0·66 0·76 0·82 0·87 0·45 0·79 0·49 Ab 60·5 46·8 51·4 54·2 67·3 72·1 64·3 59·9 55·1 63·7 67·9 63·8 43·0 43·2 64·8 62·1 62·2 62·8 62·5 37·6 39·9 68·5 An 35·3 50·5 45·6 42·4 29·7 25·1 33·0 35·2 42·0 30·6 27·4 30·8 55·1 54·8 31·7 34·1 33·5 32·6 32·5 59·8 55·6 28·7 Or 4·2 2·6 3·0 3·3 3·0 2·8 2·7 4·8 2·9 5·7 4·7 5·3 1·9 2·0 3·4 3·8 4·3 4·6 5·0 2·6 4·6 2·8 Trace element (ppm) Rb 2·56 1·70 1·74 1·67 2·31 3·35 4·03 3·43 2·86 4·83 4·26 2·28 1·79 1·77 2·07 1·61 2·32 3·11 4·89 10·0 33·8 2·29 Sr 606 1205 1224 996 820 611 635 1152 1111 857 422 791 939 942 819 763 794 763 809 864 838 505 Y 1·66 0·55 0·57 0·76 0·53 0·65 0·88 0·67 1·49 0·54 0·81 0·39 0·80 1·55 0·65 0·70 0·66 0·68 0·80 1·27 1·85 0·40 Ba 226 304 328 307 294 93·9 184 406 294 491 185 447 187 187 434 346 334 326 336 162 180 120 La 22·2 8·21 7·78 13·9 14·8 16·2 14·8 15·6 12·1 17·3 30·5 16·1 5·46 8·59 17·4 17·5 16·1 16·4 14·1 8·18 8·00 16·2 Ce 35·3 12·7 10·5 19·0 20·8 22·6 20·1 20·3 17·9 20·8 39·0 20·7 8·74 14·0 24·1 26·2 22·4 23·3 18·7 14·6 13·2 23·8 Pr 3·32 1·29 0·90 1·61 1·95 2·08 1·80 1·82 1·63 1·75 3·21 1·72 0·79 1·65 2·34 2·18 1·85 1·95 1·60 1·47 1·36 1·86 Nd 10·5 3·96 4·09 4·92 4·77 5·44 4·69 5·36 6·27 5·07 9·13 4·64 2·98 5·13 6·51 6·57 5·61 6·01 3·83 4·75 4·53 5·63 Sm 1·45 0·66 0·56 0·43 0·25 0·77 0·93 0·15 0·78 0·54 1·71 0·71 0·43 0·51 0·71 0·64 0·92 0·71 0·60 0·97 0·53 1·14 Eu 4·31 1·96 1·95 2·38 2·43 1·75 2·49 2·32 1·97 3·57 2·07 3·09 1·89 0·84 2·41 2·05 2·54 2·54 2·53 1·69 2·52 1·93 Gd 0·59 0·17 0·15 0·40 0·077 0·16 0·28 0·36 0·44 0·27 1·18 0·15 0·59 0·13 0·45 0·37 0·61 0·00 0·00 0·47 1·06 0·24 Tb 0·10 0·04 0·04 0·01 0·00 0·03 0·01 0·04 0·08 0·04 0·05 0·07 0·03 0·03 0·09 0·05 0·00 0·00 0·00 0·01 0·08 0·03 Dy 0·16 0·02 0·26 0·21 0·00 0·22 0·21 0·09 0·22 0·07 0·29 0·24 0·16 0·47 0·03 0·16 0·13 0·13 0·46 0·26 0·35 0·00 Ho 0·06 0·06 0·00 0·03 0·00 0·05 0·07 0·04 0·07 0·00 0·03 0·07 0·00 0·04 0·01 0·01 0·00 0·00 0·01 0·03 0·10 0·02 Er 0·00 0·14 0·12 0·17 0·00 0·23 0·04 0·07 0·18 0·11 0·00 0·03 0·00 0·00 0·00 0·06 0·00 0·22 0·26 0·02 0·05 0·34 Tm 0·00 0·00 0·00 0·01 0·02 0·02 0·03 0·02 0·00 0·00 0·00 0·03 0·02 0·02 0·05 0·02 0·03 0·00 0·01 0·04 0·00 0·03 Yb 0·02 0·05 0·03 0·07 0·05 0·00 0·09 0·12 0·28 0·14 0·00 0·05 0·09 0·11 0·00 0·00 0·09 0·11 0·41 0·13 0·00 0·06 Lu 0·02 0·00 0·00 0·02 0·01 0·02 0·02 0·00 0·00 0·04 0·00 0·01 0·00 0·11 0·00 0·08 0·00 0·03 0·00 0·00 0·00 0·01 Pb 26·4 6·2 6·6 11·8 15·7 18·2 15·9 10·5 9·5 16·9 20·9 15·8 11·4 9·5 13·7 13·3 12·5 12·1 13·2 12·6 13·5 16·3 Sample 15TL-08-01 15TL-08-4-02 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10 11 12 Major element (wt %) SiO2 58·8 55·1 56·1 56·9 60·0 61·1 59·1 58·2 56·6 59·4 60·8 60·3 53·9 54·0 59·7 59·4 59·4 59·9 59·4 52·8 53·9 60·8 TiO2 0·01 0·02 0·03 0·02 0·01 0·01 0·01 0·01 0·04 0·01 0·02 0·01 0·04 0·01 0·01 0·01 0·01 0·01 0·01 0·06 0·03 0·01 Al2O3 25·7 27·9 27·4 27·1 24·9 24·2 25·3 26·2 27·3 25·3 24·3 24·5 28·7 28·8 25·0 25·1 25·1 24·7 25·1 29·3 28·8 24·2 FeO 0·091 0·48 0·20 0·16 0·17 0·21 0·26 0·19 0·20 0·19 0·30 0·23 0·46 0·37 0·24 0·24 0·23 0·23 0·25 0·70 0·37 0·22 MnO 0·00 0·01 0·01 0·01 0·00 0·00 0·00 0·00 0·01 0·00 0·00 0·00 0·01 0·01 0·00 0·00 0·00 0·00 0·00 0·01 0·01 0·00 MgO 0·01 0·05 0·02 0·02 0·01 0·01 0·02 0·02 0·01 0·01 0·02 0·01 0·03 0·06 0·01 0·02 0·02 0·01 0·02 0·02 0·02 0·02 CaO 7·41 10·4 9·50 8·81 6·25 5·30 7·05 7·38 8·74 6·44 5·75 6·42 11·4 11·3 6·69 7·17 7·05 6·82 6·82 12·2 11·4 6·07 Na2O 7·05 5·32 5·92 6·23 7·85 8·41 7·62 6·95 6·36 7·42 7·88 7·36 4·93 4·93 7·57 7·22 7·26 7·27 7·25 4·26 4·53 8·03 K2O 0·74 0·45 0·53 0·58 0·54 0·50 0·48 0·85 0·50 1·02 0·82 0·93 0·33 0·35 0·61 0·66 0·76 0·82 0·87 0·45 0·79 0·49 Ab 60·5 46·8 51·4 54·2 67·3 72·1 64·3 59·9 55·1 63·7 67·9 63·8 43·0 43·2 64·8 62·1 62·2 62·8 62·5 37·6 39·9 68·5 An 35·3 50·5 45·6 42·4 29·7 25·1 33·0 35·2 42·0 30·6 27·4 30·8 55·1 54·8 31·7 34·1 33·5 32·6 32·5 59·8 55·6 28·7 Or 4·2 2·6 3·0 3·3 3·0 2·8 2·7 4·8 2·9 5·7 4·7 5·3 1·9 2·0 3·4 3·8 4·3 4·6 5·0 2·6 4·6 2·8 Trace element (ppm) Rb 2·56 1·70 1·74 1·67 2·31 3·35 4·03 3·43 2·86 4·83 4·26 2·28 1·79 1·77 2·07 1·61 2·32 3·11 4·89 10·0 33·8 2·29 Sr 606 1205 1224 996 820 611 635 1152 1111 857 422 791 939 942 819 763 794 763 809 864 838 505 Y 1·66 0·55 0·57 0·76 0·53 0·65 0·88 0·67 1·49 0·54 0·81 0·39 0·80 1·55 0·65 0·70 0·66 0·68 0·80 1·27 1·85 0·40 Ba 226 304 328 307 294 93·9 184 406 294 491 185 447 187 187 434 346 334 326 336 162 180 120 La 22·2 8·21 7·78 13·9 14·8 16·2 14·8 15·6 12·1 17·3 30·5 16·1 5·46 8·59 17·4 17·5 16·1 16·4 14·1 8·18 8·00 16·2 Ce 35·3 12·7 10·5 19·0 20·8 22·6 20·1 20·3 17·9 20·8 39·0 20·7 8·74 14·0 24·1 26·2 22·4 23·3 18·7 14·6 13·2 23·8 Pr 3·32 1·29 0·90 1·61 1·95 2·08 1·80 1·82 1·63 1·75 3·21 1·72 0·79 1·65 2·34 2·18 1·85 1·95 1·60 1·47 1·36 1·86 Nd 10·5 3·96 4·09 4·92 4·77 5·44 4·69 5·36 6·27 5·07 9·13 4·64 2·98 5·13 6·51 6·57 5·61 6·01 3·83 4·75 4·53 5·63 Sm 1·45 0·66 0·56 0·43 0·25 0·77 0·93 0·15 0·78 0·54 1·71 0·71 0·43 0·51 0·71 0·64 0·92 0·71 0·60 0·97 0·53 1·14 Eu 4·31 1·96 1·95 2·38 2·43 1·75 2·49 2·32 1·97 3·57 2·07 3·09 1·89 0·84 2·41 2·05 2·54 2·54 2·53 1·69 2·52 1·93 Gd 0·59 0·17 0·15 0·40 0·077 0·16 0·28 0·36 0·44 0·27 1·18 0·15 0·59 0·13 0·45 0·37 0·61 0·00 0·00 0·47 1·06 0·24 Tb 0·10 0·04 0·04 0·01 0·00 0·03 0·01 0·04 0·08 0·04 0·05 0·07 0·03 0·03 0·09 0·05 0·00 0·00 0·00 0·01 0·08 0·03 Dy 0·16 0·02 0·26 0·21 0·00 0·22 0·21 0·09 0·22 0·07 0·29 0·24 0·16 0·47 0·03 0·16 0·13 0·13 0·46 0·26 0·35 0·00 Ho 0·06 0·06 0·00 0·03 0·00 0·05 0·07 0·04 0·07 0·00 0·03 0·07 0·00 0·04 0·01 0·01 0·00 0·00 0·01 0·03 0·10 0·02 Er 0·00 0·14 0·12 0·17 0·00 0·23 0·04 0·07 0·18 0·11 0·00 0·03 0·00 0·00 0·00 0·06 0·00 0·22 0·26 0·02 0·05 0·34 Tm 0·00 0·00 0·00 0·01 0·02 0·02 0·03 0·02 0·00 0·00 0·00 0·03 0·02 0·02 0·05 0·02 0·03 0·00 0·01 0·04 0·00 0·03 Yb 0·02 0·05 0·03 0·07 0·05 0·00 0·09 0·12 0·28 0·14 0·00 0·05 0·09 0·11 0·00 0·00 0·09 0·11 0·41 0·13 0·00 0·06 Lu 0·02 0·00 0·00 0·02 0·01 0·02 0·02 0·00 0·00 0·04 0·00 0·01 0·00 0·11 0·00 0·08 0·00 0·03 0·00 0·00 0·00 0·01 Pb 26·4 6·2 6·6 11·8 15·7 18·2 15·9 10·5 9·5 16·9 20·9 15·8 11·4 9·5 13·7 13·3 12·5 12·1 13·2 12·6 13·5 16·3 Sample 14ZJ58 14ZJ59 15TL-09-1-02 12TL-03-2 1 2 3 1 2 3 4 5 6 1 2 3 5 1 2 3 4 5 6 7 Major element (wt %) SiO2 59·8 59·1 59·1 61·1 59·8 59·4 55·2 56·1 55·4 59·1 52·4 57·4 59·3 54·9 56·4 55·7 52·3 53·2 52·7 55·2 TiO2 0·01 0·01 0·01 0·00 0·01 0·01 0·03 0·02 0·03 0·01 0·01 0·06 0·01 0·03 0·03 0·01 0·03 0·21 0·02 0·02 Al2O3 24·8 25·4 25·5 24·1 24·9 25·3 27·9 27·5 28·0 25·5 30·0 26·2 25·3 28·2 26·3 27·4 29·7 28·2 29·8 27·9 FeO 0·18 0·19 0·21 0·16 0·19 0·20 0·22 0·22 0·20 0·20 0·22 0·38 0·18 0·36 0·34 0·24 0·37 0·66 0·34 0·32 MnO 0·00 0·00 0·00 0·00 0·00 0·00 0·00 0·00 0·00 0·00 0·01 0·01 0·00 0·00 0·01 0·01 0·01 0·02 0·00 0·00 MgO 0·01 0·01 0·02 0·01 0·01 0·01 0·01 0·01 0·01 0·01 0·01 0·01 0·01 0·03 0·02 0·01 0·02 0·12 0·02 0·03 CaO 7·17 7·55 8·09 5·67 6·91 6·84 10·4 9·69 9·97 6·98 12·7 8·39 6·58 10·9 10·5 10·5 13·2 13·0 13·4 10·8 Na2O 7·04 6·97 6·54 8·26 7·11 7·19 5·50 5·79 5·72 7·31 4·17 6·98 7·72 5·15 5·58 5·24 3·61 3·96 3·38 5·19 K2O 0·79 0·57 0·34 0·56 0·84 0·87 0·40 0·45 0·41 0·73 0·27 0·42 0·68 0·28 0·65 0·62 0·57 0·43 0·18 0·30 Ab 61·1 60·5 58·2 70·2 61·9 62·3 47·8 50·6 49·7 62·7 36·8 58·7 65·4 45·3 47·2 45·6 32·0 34·6 31·0 45·6 An 34·4 36·3 39·8 26·7 33·3 32·8 49·9 46·8 48·0 33·1 61·7 39·0 30·8 53·0 49·2 50·8 64·6 62·9 67·9 52·6 Or 4·5 3·3 2·0 3·1 4·8 5·0 2·3 2·6 2·4 4·1 1·6 2·3 3·8 1·6 3·6 3·6 3·3 2·5 1·1 1·8 Trace element (ppm) Rb 9·14 5·56 1·93 2·97 1·31 1·54 0·64 0·73 0·39 3·43 0·47 3·44 2·97 0·36 14·3 15·4 19·8 13·4 0·74 1·18 Sr 417 417 359 661 882 920 1071 1084 1091 661 1067 422 796 1250 985 1075 1096 1110 992 1252 Y 0·91 2·81 2·89 0·44 0·47 0·49 0·66 0·53 0·50 0·46 1·50 2·83 0·47 0·64 0·73 0·31 10·8 14·7 0·94 0·53 Ba 215 174 156 63·4 452 498 259 324 298 342 182 104 281 274 102 96·2 124 171 151 237 La 15·6 25·4 19·9 20·8 20·0 17·5 7·63 8·19 7·72 16·5 10·8 30·0 14·3 10·3 13·4 12·4 14·4 15·2 6·90 10·9 Ce 21·8 34·5 30·7 25·9 25·3 23·8 11·5 13·1 11·8 22·0 19·3 45·6 19·0 15·8 17·2 14·6 27·8 34·4 10·5 15·6 Pr 1·73 3·08 2·69 2·11 2·17 1·93 1·10 1·26 1·18 1·81 2·06 4·27 1·60 1·50 1·34 1·15 3·45 4·42 1·11 1·25 Nd 4·50 9·26 8·77 4·85 5·59 5·95 4·05 3·59 2·53 6·13 7·04 12·4 5·12 4·38 3·30 2·73 13·4 16·6 3·49 3·86 Sm 0·82 1·67 1·57 0·50 0·84 0·62 0·81 0·84 0·47 0·53 1·23 1·67 0·34 0·51 0·36 0·50 3·64 3·30 0·65 0·64 Eu 2·49 2·19 2·28 3·53 5·57 4·89 2·29 2·29 2·17 2·96 1·99 2·26 2·75 1·99 1·35 1·31 2·25 2·64 1·01 2·23 Gd 0·52 0·88 1·21 0·48 0·54 0·59 0·3