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Article

Mineralogical Characteristics of Biotite and Chlorite in Zuluhong Polymetallic Deposit: Implications for Petrogenesis and Paragenesis Mechanisms of the Tungsten and Copper

by
Rui Cao
1,2,
De-Fan Chen
2,*,
Hao-Dong Gu
3,
Bin Chen
4 and
Sheng-Chao Yan
5
1
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China
2
College of Earth Science, Chengdu University of Technology, Chengdu 610059, China
3
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China
4
Department of Earth and Space Sciences, Southern University of Science and Technology, Shenzhen 518055, China
5
State Kay Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
*
Author to whom correspondence should be addressed.
Minerals 2022, 12(10), 1280; https://doi.org/10.3390/min12101280
Submission received: 7 September 2022 / Revised: 7 October 2022 / Accepted: 7 October 2022 / Published: 12 October 2022
(This article belongs to the Special Issue Tectono-Magmatic Evolution and Metallogeny of Tethyan Orogenic Belts)
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Abstract

:
The Zuluhong quartz-vein-type polymetallic deposit, located in the Alatau area of Western Tianshan, China, is a particular and typical tungsten deposit associated with copper. This paper presents major and trace element analyses of magmatic and altered (i.e, chloritized) biotite from the deposit, in order to identify the source of the magmas and characterize the mineralization physical-chemical condition. Magmatic biotite is Fe-rich and has high Rb/Ba ratios (0.27–9.14), indicative of extensive differentiation of granite. Moreover, magmatic biotite has total rare earth element (∑REE) contents that are 5–10% of the whole-rock contents, shows slight light REE depletion, and negative Ce anomalies. Magmatic biotite is enriched in some large-ion lithophile elements (LILE; e.g., Rb and K) and depleted in some high-field-strength elements (HFSE; e.g., Th and Nb). These geochemical features, coupled with geological evidence, indicate that the Zuluhong intrusion is a highly fractionated I-type granite derived from lower crustal melting. During ore formation, magmatic biotite was partially to totally altered to chlorite due to interaction with ore-forming fluids. The temperature and oxygen fugacity decreased during alteration. The mineralization in the Zuluhong polymetallic deposit can be divided into at least two stages. In the early stage, quartz-vein-type wolframite mineralization formed from Si- and volatile-rich fluids that were derived from fractionated granitic magma. In the later stage, W–Cu ores formed as metal sulfides were dominated by chalcopyrite. The later ore-forming fluids experienced a decrease in temperature and oxygen fugacity as they reacted (i.e, chloritization and lesser silicification) with reducing wall rocks around the contact zone of the intrusion.

1. Introduction

The Alatau area in the Western Tianshan, China, is located at the southwestern margin of the Central Asian Orogenic Belt (CAOB). This region has experienced numerous late Paleozoic magmatic events [1], as well as large-scale Cu polymetallic mineralization [2,3]. The Zuluhong W–Cu polymetallic deposit is a newly discovered deposit in the Alatau area. However, it is generally considered that W and Cu do not coexist in the same mineralization area [4], due to their different ore-forming processes [5,6], source magmas [7,8,9,10], and ore-forming fluids [11,12,13]. Few previous studies have examined the Zuluhong deposit, focusing mainly on the age and petrology of the associated granite [14]. The nature of the late mineralization fluid and changes in oxygen fugacity during magma evolution in the Zuluhong deposit have not been studied. As such, the mechanism of W–Cu paragenesis remains unclear.
Biotite is a significant ferromagnesian mineral in granite, and records both the nature and physicochemical conditions (e.g., temperature and oxygen fugacity) of the granite magma from which it formed [15,16,17,18,19,20]. Chlorite is a ubiquitous product of fluid–rock interactions in hydrothermal systems, and can be used to constrain the changing temperature and oxygen fugacity conditions during alteration [21,22,23,24]. Physicochemical conditions and fluid evolution can be revealed through studies of different types of biotite, particularly magmatic and altered biotite. For example, through the study of biotites in altered rocks, Yuguchi et al. [25] constrained the pH and redox evolution during alteration. Similarly, a biotite study of the Darreh–Zar porphyry Cu deposit by Parsapoor et al. [26] revealed the temperature and pressure changes during alteration, as well as the volatile chemistry of the fluids involved.
Magmatic biotites in the Zuluhong granite body are euhedral with a high degree of crystallinity, but around mineralized quartz veins, alteration is strong and dominated by the chloritization of biotite. This study investigates the magma source and evolution, fluid properties, and oxygen fugacity changes during alteration, through major and trace element analyses of magmatic and altered biotite in the Zuluhong deposit. The results provide new perspectives on metallogenic models of tungsten deposit associated with copper.

2. Regional Geological and Mineralization Background

The Alatau area was a Paleozoic active continental margin in the Yili Plate between the Junggar and Tarim plates and was an important component of the Eurasian Central Asia–Mongolia–Okhotsk arc orogenic belt (Figure 1a). The basement rocks comprise mainly Paleozoic strata, including the upper Devonian Tuosikuertawu, lower Carboniferous Aksha, upper Carboniferous Dongtujinhe, and lower Permian Wulang formations. Precambrian basement has not been located in this region. Late Paleozoic magmatism in this area led to the emplacement of intermediate–silicic hypabyssal rocks, which were closely related to the mineralization. The intrusive rocks are mainly dikes and stocks. Metamorphic rocks are not well-developed in this area, apart from hornfels in contact metamorphic zones between the intrusions and wall rocks. The area is crossed by several dextral strike-slip and thrust faults, and folds are only found in the lower Carboniferous Aksha Formation.
A series of Cu polymetallic deposits (e.g., the Lamasu Cu–Zn and Kekesai, Dongtujin, and Dabate Cu–Mo deposits) (Figure 1b) occur in the Alatau area. The Zuluhong W–Cu polymetallic deposit has been found recently, located at 81° E and 45°N, 34 km north of Wenquan County to the north of Xinjiang [27]. The strata in the Zuluhong mine are mainly the lower Carboniferous Aksha Formation, comprising micrites, sandstones, siltstones, and slates. The Zuluhong intrusion are composed of monzogranite and granodiorite in the mining area and are formed at 320 ± 2 Ma and 309 ± 1 Ma, respectively [28]. The intrusion was emplaced into early Carboniferous strata, has an irregular oval shape, and extends over an area of ~10 km2. The intrusion is zoned from a marginal facies of porphyritic fine-grained biotite monzogranite to an internal facies of porphyritic medium-grained biotite monzogranite. The structure of the mining area includes a main NE–SW-striking thrust fault, which controls the distribution of the intrusion and orebody (Figure 1c).
The Zuluhong Granite can be divided into a monzogranite and porphyritic granodiorite from its core to rim. Several ore minerals are found in different types of mineralized quartz veins, which allows the veins to be divided into early and late stages. The main minerals in the early quartz veins are wolframite and quartz. Wolframite is mostly 2–5 cm and up to 8 cm in size, euhedral, and occurs as aggregates or single crystals (Figure 2a). The contacts between wolframite and quartz are smooth without a metasomatic texture (Figure 2b), indicating that wolframite and quartz co-crystallized. The mineralogical features of the late quartz veins are more complex than those of the early veins. The main minerals in the late quartz veins are wolframite, chalcopyrite, pyrite, and quartz. The characteristics of wolframite are similar in the two types of veins. Chalcopyrite (Figure 2c,d) and pyrite (Figure 2e) replace wolframite or infill voids and cleavage planes (Figure 2f). Extensive alteration is evident around the late quartz veins, mainly chloritization. As such, the two major mineralization stages were a quartz–wolframite stage and a sulfide stage. Biotite was altered to chlorite during the second stage.

3. Analytical Methods

Ten thin sections of the Zuluhong Granite were studied using a microscope (ECLIPSE LV100N POL). EDX map of the biotite was collected at the School of Earth Sciences, Chengdu University of Technology, Chengdu, China, using a Nova 450 field-emission scanning electron microscope at a voltage of 30 kV. Major element compositions of biotite were acquired at the School of Earth Sciences and Resources, Chinese University of Geology, Wuhan, China, using a JEOL JXA-8230 electron microprobe analyzer (EMPA) operated at a voltage of 15 kV, beam current of 20 nA, spot size of 1μm, and maximum counting time of 20 s. SPI standard minerals were used as standards. X-ray intensities were corrected using the ZAF methodology. Analytical errors on the major element determinations are estimated to be ~1% relative.
Trace element compositions of biotite were determined by laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) at the School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, China. The analyses were conducted with a GeoLas193 LA system and an Agilent 7500a ICP–MS equipped with a shield torch. Analyses employed He as the ablation and carrier gas (0.65 L/min), a laser repetition rate of 6 Hz, and a laser spot size diameter of 32 μm. The analytical precision was better than 5% and GSE-1G was used as a standard. Silica contents determined by microprobe analysis were used to perform internal corrections for LA–ICP–MS data.

4. Results

4.1. Petrographic Description

Three Zuluhong biotite monzogranite samples were collected in the study area. The Zuluhong biotite monzogranite has a granitic and medium- to fine-grained texture and massive structure. The main rock-forming minerals are quartz (30–35 wt%), alkali feldspar (35–40 wt%), plagioclase (15–20 wt%), and biotite (~8%). No hornblende or muscovite are present. Accessory minerals (~2 wt%) include zircon, ilmenite, and apatite. Magmatic biotite (Figure 3a) in the Zuluhong monzogranite has an idiomorphic or hypidiomorphic texture and displays a distinct pleochroism (light to dark brown). Some accessory minerals (e.g., apatite and fluorite) are found as inclusions in the magmatic biotite. Around mineralized quartz veins, biotite is altered to chlorite. Where biotite is partially altered (Figure 3b,c), chloritization has generally occurred along cleavages and cracks, and the pleochroism is from light brown to brown. Some biotites are completely replaced by chlorite and have a pseudomorphic texture (Figure 3d). These biotites have an idiomorphic or hypidiomorphic texture and display a distinct pleochroism from light to dark green.

4.2. Major Element Data

EMPA results for biotite and chlorite in the Zuluhong monzogranite are listed in Table 1, Table 2 and Table 3. The major element data for biotite were converted to a structural formula on the basis of 22 oxygens [30]. Data for chlorite were converted to a structural formula on the basis of 14 oxygens [31].
When data for magmatic and partially altered biotites are plotted on the Mg−(Al3+ + Fe3+ + Ti4+)–(Fe2+ + Mn2+) diagram [32], they all fall in the Fe-biotite field (Figure 4a). On the classification diagram for chlorite [33], the data fall in the field for ripidolite (Figure 4a). Biotite and chlorite are both Fe-rich and show a distinct progression in chemistry from biotite to chlorite. According to Inoue [34], Fe-rich chlorites tend to form in a reducing environment. As such, the Fe-rich chlorite in the Zuluhong monzogranite may indicate a low oxygen fugacity during and after alteration.
The chemical changes that accompanied biotite alteration were as follows. (1) Biotite alteration results in a decrease in Ti, K, and Si contents. For example, the TiO2 contents from magmatic biotite to partially altered biotite and chlorite are 1.95–2.37, 0.01–2.34, and 0–0.10 wt.%, respectively, indicating the release of Ti from biotite during alteration. The K2O contents of biotite, partially altered biotite, and chlorite are 8.67–9.72, 0.18–0.31, and 0–0.05 wt.%, and the SiO2 contents are 33.80–38.09, 23.5–33.2, and 24.24–25.95 wt.%, respectively. The gradual loss of K and Si from the biotite provides lattice space for the entry of other elements. (2) Fe, Mg, and Al contents show an increasing trend from magmatic biotite to partially altered biotite and chlorite, with FeOtot contents of 24.6–26.1 wt.% (Fe3+ = 0.1–0.22 wt.%; Fe2+ = 1.50–2.32 wt.%), 31.90–33.60 wt.% (Fe3+ = 0.1–0.21 wt.%; Fe2+ = 2.20–2.34 wt.%), and 29.32–36.37 wt.% (Fe3+ = 0.09–0.25 wt.%; Fe2+ = 5.50–6.91 wt.%), respectively. Similarly, the MgO contents are 6.6–7.8, 8.64–10.01, and 6.71–10.42 wt.%, and the Al2O3 contents are 14.6–15.3, 17.8–20.9, and 15.5–20.9 wt.%, respectively. The systematic variations in Fe, Mg, and Al contents reflect changes in the biotite crystalline structure during alteration. In addition, the changing FeOtot and, in particular, the decreasing Fe3+/Fe2+ ratio, indicate a progressive decrease in oxygen fugacity. (3) Mn, Ca, and Na contents show no significant variation, indicating that they were largely unaffected by alteration and physicochemical and redox conditions.

4.3. Rare Earth Element Data

Previous studies have indicated that biotite has low REE contents. For example, Pan et al. [35] reported ∑REE contents of 2.54–5.62 ppm for biotite from the northwestern Yunnan porphyry Cu belt, and Bea et al. [36] determined ∑REE biotite contents of 0.28–1.44 ppm for the Pena Negra complex, central Spain.
In this study, REE contents in biotite are also relatively low. Biotite in the Zuluhong monzogranite has ∑REE contents of 0.36–11.93 ppm (average = 3.40 ppm), light REE contents of 0.19–8.86 ppm (average = 2.45 ppm), heavy REE contents of 0.05–4.08 ppm (average = 0.95 ppm), and light REE/heavy REE ratios of 1.26–7.24 (average = 2.34), reflecting slight depletion of the heavy REE. The chondrite-normalized REE patterns for the Zuluhong biotites (Figure 5a) are relative flat, with a slight negative Ce anomaly. In addition, whole-rock ∑REE contents of the Zuluhong monzogranite are 127–154 ppm, and the ∑REE contents of the biotite account for 5–10% of the whole-rock REE inventory.

4.4. Trace Element Data

The Zuluhong monzogranite is enriched in large-ion lithophile elements (LILE; Rb and Sr) and depleted in high-field-strength elements (HFSE; Nb and Ti). Compared with Rb and Th, the monzogranite is depleted in Ba. The fact that the Zuluhong monzogranite is depleted in HFSE (e.g., Nb and Ta) and enriched in Zr and Sm indicates the granitic magma was formed by crustal melting (Figure 5b) [28]. Compared with the granite, the biotites are enriched in LILE (e.g., Rb, Sr, Ba, Na, and U) and depleted in HFSE (e.g., Nb, Ta, Zr, Hf, and Th), showing that biotite was the main carrier of some of these elements (Rb, Ba, Ta, Nb, and K) in the monzogranitic magma.

5. Discussion

5.1. Temperature and Oxygen Fugacity Conditions

Experimental studies that determined oxygen fugacity from biotite coexisting with magnetite and K-feldspar have used Fe3+, Fe2+, and Mg2+ contents [37]. In a Fe3+–Fe2+–Mg2+ diagram (Figure 6), data for biotites plot on the Ni–NiO buffer line. In conjunction with the formation temperature, the log(fO2) value has an estimated range from −23 to −27 (average = −23.4). Data for the partially altered biotites plot on the FMQ buffer line, indicating a decrease in temperature and oxygen fugacity as the biotite was altered.
Temperature and oxygen fugacity have a strong influence on the crystalline structure and chemical composition of chlorite [38,39,40,41]. Cathelineau and Nieva [38] first reported a positive correlation between the AlVI content of chlorite and formation temperature, and proposed a solid solution thermometer for chlorite. Nieto [39] reported a modified formula for the crystalline interplanar spacing (d001) of chlorite: d001 = 14.339 − 0.1155AlIV − 0.02011 × Fe2+. Furthermore, a mathematical relationship between d001 and the formation temperature of chlorite was proposed by Battaglia [40]: T = (14.379 − d001)/0.001. However, the reliability of this method is not ideal because the influence of whole-rock composition is not considered. Moreover, the chlorite formation temperature can also be calculated by using these equations [42,43]. Combined with the semi-empirical thermometer of Walshe [44], Inoue [41] has selected four chlorite components to establish a new thermodynamic model. Therefore, according to the method of Inoue, the formation temperature of chlorite in this study is 222.31–302.34 °C (average = 254.8 °C).
In view of the Fe/(Fe + Mg) ratio of chlorite (>0.6), the formula of Walshe [44] was used to estimate oxygen fugacity, yielding log(fO2) values from −38.85 to −44.08 (average = −40.39).

5.2. Mechanisms and Physicochemical Conditions of Alteration

The general chemical formula of biotite is XY2–3[Z4O10](OH)2 (X mainly refers to K+ and Na+, as well as some Ca2+, Ba2+, Rb+, or Cs+; Y mainly refers to Mg2+, Fe2+, Mn 2+, Fe3+, Al3+, or Ti4+; OH− can be replaced by Li+, F−, or Cl−; Z mainly refers to Si4+ or Al3+ in the tetrahedral coordination structure) [45]. The crystalline structure of biotite is the TMT+C type (the T layer is the silica tetrahedron and corresponds to Z; the M layer has an octahedral structure and corresponds to Y; the C layer refers to K+ and corresponds to X). The alteration of biotite commonly results in the formation of chlorite, which has a chemical formula of Y3[Z4O10](OH)2–Y3(OH)6 (Y mainly refers to Mg2+, Fe2+, Mn2+, Fe3+, Al3+, or Ti4+; OH− can be replaced by Li+, F−, or Cl−). The crystalline structure of chlorite is the TMT+M type. The chemical formulae indicate that with the alteration of biotite, X (K+ or Na+) decreases but Y (Fe2+ and AlVI) increases. In addition, the C layer is gradually replaced by the M layer during alteration, and the C layer (K+) eventually completely disappears; furthermore, increasing Fe2+ and Mg2+ may form an extra M layer, replacing the C layer [46].
Changes in physicochemical conditions during alteration can be reflected by mineral chemistry. The chloritization of biotite is a complex water-rock reaction process, which is controlled by temperature, oxygen fugacity, water/rock ratio, and fluid composition. It is generally accepted that the contents of Fe, Si, Ti, K, Al, and Mg recorded the greatest changes during the alteration of biotite. Previous studies have suggested that temperature shows a positive correlation with Ti content [37]. Some elements (such as Mg and Al) in the M layer of biotite can be replaced and substituted by Ti. Therefore, a continuous decline in Ti content during alteration might reflect a gradual decrease in temperature. Changes in K, Si, and AlVI contents are related to variations in crystalline structure. However, the contents of Fe, AlVI, and Mg are mainly related to changes in oxygen fugacity. Higher Fe3+/Fe2+ ratios reflect a higher oxygen fugacity. In Figure 7, Fe3+/Fe2+ ratios negatively correlate with FeO, and Al2O3 and MgO contents positively correlate with TiO2, indicating these changes reflect an increase in oxygen fugacity. This result is consistent with the negative correlation between AlVI in biotite and oxygen fugacity, as reported by Albuquerque [47].

5.3. Petrogenesis

5.3.1. Magmatic Differentiation

Previous studies have suggested that biotite is a good indicator of magmatic differentiation [48]. Rb and Ba in granitic magmas are mainly substituted into biotite and K-feldspar. Rb mainly substitutes for K, and increasing Rb content reflects magmatic differentiation. Ba can substitute for K and Ca, and during the early stages of magmatic evolution, biotite is the main host of Ba, whereas during the later stages, Ba is mainly substituted into K-feldspar. As such, magmatic evolution results in a gradual increase of Rb and decrease of Ba in biotite, and an increase in the Rb/Ba ratio. The Zuluhong monzogranite has high Rb/Ba ratios (0.27–9.14; average = 2.97), clearly indicating that it is highly differentiated [28]. This is consistent with other mineralogical and geochemical characteristics, such as its weakly peraluminous nature, absence of hornblende, high SiO2 (average 73.66 wt.%), high alkalis (average Na2O + K2O = 7.45 wt.%), high K/Ba ratio (average = 130), and depletions in Eu, Sr, Ba, and Nb.
Previous studies have suggested that biotite records systematic chemical variation during magmatic evolution [49,50]. Under the microscopic observation, we found that biotite had different optical characteristics, which may be caused by the differences in composition of a zoned biotite (Figure 8a). Thus, major element composition analysis from point 1 to point 5 of a single biotite grain was carried out by the electron microprobe analyzer (Figure 8b). The MgO content increases gradually from point 1 to point 5 (Figure 9a), whereas the FeOtot content decreases (Figure 9b). The coupled decreases in MgO and TiO2 during magma evolution (Figure 9c) show that the temperature decreased during biotite crystallization and that the changes in biotite and magmatic Fe and Mg contents reflect the fractional crystallization of biotite. During the evolution of the magma, the Na2O + K2O content increased (Figure 9d), indicating that the magma became alkali rich. Al2O3 and CaO decreased during magma evolution (Figure 9e,f), possibly caused by the fractional crystallization of feldspar (Al-rich) and apatite (Ca-rich).

5.3.2. Granite Petrogenesis

The biotite in the Zuluhong granite is Fe-rich and the main opaque mineral is ilmenite, indicating that the granite is an ilmenite-series granite [51]. The distribution of Fe and Mg in biotite is controlled mainly by the Mg/Fe ratio in the magma and temperature. In this study, Mg# (molar Mg/(Mg + Fe)) is used to represent the Mg/Fe ratio. The Fe and Mg contents of biotite show different trends with temperature, i.e., as temperature increases, the biotite becomes Mg-rich. The Mg# value of biotite in the Zuluhong granite is 0.45–0.55, which indicates a low crystallization temperature. Magnetite-series granitoids are considered to have deep sources (upper mantle or lowest crust) and contain Mg-rich biotite, whereas ilmenite-series granitoids have relatively shallow sources (middle to lower continental crust) and contain Fe-rich biotite. The MF value (molar Mg/(Mg + Fe + Mn)) of biotite is also an important indicator in identifying the magma source. The MF value of biotite in mantle rocks is >0.45, whereas in crustal rocks it is <0.45. The MF values of biotite in the Zuluhong granite are 0.28–0.35 and the granite is Fe-rich, indicating that it was derived from the lower crust [52].
Aluminum saturation in granites is key to distinguishing between I- and S-type granites, with the differences between these granites reflecting the source rock and fractional crystallization processes. In this study, the A/CNK value (molar Al2O3/(Na2O + K2O + CaO)) is used to represent the degree of aluminum saturation. Major (wt.%) and trace (×10−6) element data of the Zuluhong granite are listed in Table 4 [28]. The source rocks of S-type granites are derived from the middle–upper crust and are typically highly weathered sedimentary rocks in which Al is relatively stable, but Na, K, and Ca have been lost due to weathering, thereby producing peraluminous granites. I-type granite source rocks are undersaturated or oversaturated in Al and, as in the Zuluhong granite, fractional crystallization changes the Al content in the evolving magma. Zen [53] noted that hornblende crystallization (A/CNK < 0.5) is inevitable in the production of peraluminous melts. According to the Bowen reaction sequence, amphibole crystallizes before biotite. Given that there is no hornblende in the Zuluhong granite, it is clear that the granite is highly differentiated. Na, K, Ca, and Mg are removed from melt by the fractional crystallization of minerals with low A/CNK values (e.g., pyroxene and hornblende), which results in the formation of peraluminous melt. Chappell [54] proposed that the generation of weakly peraluminous granites is controlled mainly by the nature of the source rock, rather than fractional crystallization, and so S-type granites are always more Al-oversaturated than I-type granites. Gao [55] developed a Mg# versus A/CNK classification diagram for biotite and, in this diagram, data for the Zuluhong granite plot in the I-type granite field (Figure 10). This is consistent with the absence of the diagnostic primary Al-rich minerals (e.g., muscovite and cordierite) of S-type granites in the Zuluhong granite. As such, the Al-saturation in the Zuluhong granite must be the result of fractional crystallization. In addition, the AlVI value of biotite in the Zuluhong granite is 0.17–0.26, which is characteristic of the lower AlVI values of biotite in I-type granites.

5.4. Implications for Tectonic Setting

The Zuluhong monzogranite intruded the lower Carboniferous Aksha Formation and was formed during the Visean stage (346–330 Ma), according to biostratigraphic constraints. The Aksha Formation comprises a shallow-marine carbonate and clastic rock formation, typical of the sedimentary environment in a back-arc basin [57]. The zircon U–Pb age of the Zuluhong monzogranite is 320 ± 2 Ma [28]. The presence of the Bayingou ophiolite (325–334 Ma) [58], arc basalts (320–334 Ma) [59], and a “stitching pluton” (zircon U–Pb age of 316 Ma) in an ophiolite in northern Tianshan indicate that the western Tianshan was a complex trench–arc–basin system at ca. 320 Ma. The long period of subduction and collision in the western Tianshan region caused thickening of the lower crust, forming the Aksha Formation. Continuous stretching of a back-arc basin results in heat being transferred from the upper mantle to the crust and the development of an anomalously high geothermal gradient, which can cause melting of the lower crust.
The Paleo-Asian oceanic lithosphere was being subducted during the late Paleozoic, which may have led to crustal thickening, crustal melting, and the formation of granitic magma. The Zuluhong granite was derived from the lower crust, and its high SiO2 and total alkalis are consistent with the compositions of granitic magma experimentally produced by the partial melting of basaltic rocks [60]. Hence, the Zuluhong granite may have been produced by the partial melting of basaltic rocks in the lower crust.

5.5. Coupled W–Cu Mineralization

There is considerable variation in the W and Cu mineralization processes, given that: (1) W is an incompatible element and enriched in continental crust, whereas Cu is a compatible element and enriched in the mantle [61]; (2) W ores are mostly quartz-vein- and skarn-type [5], whereas Cu ores are found mainly in porphyry deposits [62]; (3) W ores are generally associated with granitic magmas that are highly fractionated (high-Si) and have low oxygen fugacity [7,9,63], whereas Cu ores are typically associated with granitic magmas that have experienced little fractionation (intermediate–silicic) and have high oxygen fugacity [8,64]; and (4) W ore-forming fluids have medium–low salinity and high F content [65], whereas Cu ore-forming fluids have high salinity and high Cl (or S) content [12,13,66]. Therefore, it is unusual for both W and Cu to be present in the same ore deposit [14].
Several large W–Cu ore deposits have been recently found in China, such as at Xushan and Zhuxi in the Jiangnan orogenic belt [67,68]. The Zuluhong polymetallic deposit is also a W–Cu ore deposit and has some features that differ from those of the deposits in the Jiangnan orogenic belt. Firstly, the magma source rocks of the W–Cu deposits in the Jiangnan orogenic belt are crustal sediments and the granites are S-type granites with limited mantle input [69,70]. However, the Zuluhong monzogranite has high SiO2, high alkalis, high FeO/MgO ratios (average = 4.2), high Rb/Sr ratios (average = 1.68), negative Ce anomalies, and contains accessory fluorite and tourmaline. These features demonstrate that the Zuluhong monzogranite is a highly fractionated, I-type granite. Secondly, the ore-forming elements (i.e, W and Cu) in the deposits of the Jiangnan orogenic belt are partly magma derived [71,72], whereas the Zuluhong monzogranite has relatively low contents of the ore-forming elements [27]. Thirdly, there are several types of mineralization in the Jiangnan orogenic belt, such as altered-granite-, quartz-vein-, and veinlet–disseminated-types, and the mineralized veins are found mainly in the granite pluton [73]. However, the main type of mineralization in the Zuluhong deposit is the quartz-vein-type, and the quartz veins are found mainly in the contact metamorphic zone. As such, the Zuluhong W–Cu polymetallic deposit represents an interesting new type of W–Cu mineralization.
During alteration, both the temperature and oxygen fugacity decreased. Firstly, the temperature dropped to 209–248 °C (average = 237 °C) (the formation temperature of chlorite), and the average oxygen fugacity [log(fO2)] dropped from −24.3 to −41.3. The temperature and oxygen fugacity of wolframite and sulfide (chalcopyrite and pyrite) formation are different. The temperature of wolframite formation related to quartz veins is 330–380 °C (average = 350 °C) [62,74]. This temperature is slightly higher than that of the crystallization temperature of chlorite. Thus, there is only a short time interval between the crystallization of chlorite and that of wolframite. The temperature of sulfide formation ranges from 100 to 700 °C, but when sulfide crystallizes during late hydrothermal stages, the temperature is ~228 °C [75]. This temperature is close to that of chlorite formation. In magmas, W exists in the form of W6+. A change in oxygen fugacity cannot change the valence of W in magmas or the solubility of W6+ in the melt [76,77]. However, at high oxygen fugacities, the partition coefficient for W6+ between melt and ore minerals increases and W6+ tends to enter metallic minerals and form W ores [78]. Sulfur exists in the form of S2− in sulfides and is readily oxidized under high oxygen fugacities. As such, the formation of sulfides requires a low oxygen fugacity.
In summary, the Zuluhong ore deposit formed over at least two stages. During the first stage, granitic magma differentiated and evolved to form the early ore-forming fluids with high Si content and oxygen fugacity. These fluids precipitated wolframite in early quartz veins. During the second stage, the fluid interacted with reducing wall rocks and the temperature and oxygen fugacity decreased as biotite was altered to chlorite. Wall rock alteration in the deposit is strong, and includes greisenization, silicification, and chloritization. In the second mineralization stage, chalcopyrite and pyrite replaced wolframite or infilled voids and cleavage planes, resulting in the formation of late quartz veins.

6. Conclusions

  • Magmatic biotite in the Zuluhong monzogranite has an idiomorphic or hypidiomorphic texture and contains inclusions of the accessory minerals apatite and fluorite. The biotite is Fe-rich with a high Rb/Ba ratio (0.27–9.14), which indicates that the Zuluhong monzogranite is highly differentiated. Magmatic biotite has ∑REE contents that are 5–10% of the whole-rock REE inventory and shows slight light REE depletion and negative Ce anomalies. Magmatic biotite is also enriched in some LILE (e.g., Rb and K) and depleted in some HFSE (e.g., Nb and Ti). Based on geological constraints and geochemical data, we suggest that the Zuluhong monzogranite was derived by lower-crustal melting due to heating from asthenospheric upwelling.
  • Around mineralized quartz veins, some biotite is partially to completely altered to chlorite. Chlorite mineral chemistry record a temperature range from 209 to 248 °C and a change in oxygen fugacity [log(fO2)] from −24.3 to −41.3 during alteration.
  • The formation of the Zuluhong ore deposit can be divided into at least two stages: (a) differentiation and evolution of granite magma to produce the early ore-forming fluids with high Si contents and oxygen fugacity, which precipitated quartz-vein-type wolframite; and (b) fluid interaction with reducing wall rocks, biotite alteration to chlorite, and decreasing temperature and oxygen fugacity, which led to the formation of sulfide minerals such as chalcopyrite and pyrite after wolframite.

Author Contributions

Investigation, R.C., B.C. and S.-C.Y.; methodology and writing-original draft preparation, R.C., D.-F.C. and H.-D.G. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Second Tibetan Plateau Scientific Expedition and Research (STEP) Programme (2019QZKK0804), the National Natural Science Foundation of China (U21A2015), and the key research and development program in Tibet (XZ202101ZY0014G).

Data Availability Statement

The data presented in this work are available on request from the corresponding author.

Acknowledgments

The authors thank Fangyue Wang for constructive comments that helped to improve the experiment. We also thank Xinghua Ma for help with thoughtful discussions and informal reviews.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Xiao, W.; Windley, B.F.; Badarch, G.; Sun, S.; Li, J.; Qin, K.Z.; Wang, Z. Palaeozoic accretionary and convergent tectonics of the southern altaids: Implications for the growth of Central Asian. J. Geol. Soc. 2004, 161, 339–342. [Google Scholar] [CrossRef]
  2. Zhang, Z.; Wang, Z.; Wang, L.; Zuo, G. Metallogenic epoch and ore-forming environment of the lamasu skarn-porphyritic cu-zn deposit, western tianshan, xinjiang, NW china. Acta Geol. Sin. 2008, 82, 731–740. [Google Scholar] [CrossRef]
  3. Tang, G.J.; Wang, Q.; Derek, A.W.; Sun, M.; Li, Z.X.; Sun, W.D.; Jia, X.H.; Jiang, Z.Q. Geochronology and geochemistry of Late Paleozoic magmatic rocks in the Lamasu-Dabate area, northwestern Tianshan (West China): Evidence for a tectonic transition from arc to post-collisional setting. Lithos 2010, 119, 393–411. [Google Scholar] [CrossRef] [Green Version]
  4. Jiang, S.Y.; Peng, N.J.; Huang, L.C.; Xu, Y.M. Geological characteristic and ore genesis of the giant tungsten deposits from the Dahutang ore-concentrated district in northern Jiangxi Province. Acta Petrol. Sin. 2015, 31, 639–655. [Google Scholar]
  5. Candela, P.A.; Bouton, S.L. The influence of oxygen fugacity on tungsten and molybdenum partitioning between silicate melts and ilmenite. Econ. Geol. 1990, 85, 633–640. [Google Scholar] [CrossRef]
  6. Mao, J.W.; Luo, M.C.; Xie, G.Q.; Liu, J.; Wu, S.H. Basic characteristics and new advances in research and exploration on porphyry copper deposits. Acta Geol. Sin. 2014, 88, 2153–2175. [Google Scholar]
  7. Lu, H.Z. Mineralization and fluid inclusion study of the Shizhuyuan W-Sn-Bi-Mo-F skarn deposit, Hunan province, China. Econ. Geol. 2003, 98, 955–974. [Google Scholar] [CrossRef]
  8. Teixeira, R.J.S.; Neiva, A.M.R.; Gomes, M.E.P.; Corfu, F.; Cuesta, A.; Croudace, I.W. The role of fractional crystallization in the genesis of early syn-D3, tin-mineralized Variscan two-mica granites from the Carrazeda de Ansiaes area, northern Portugal. Lithos 2012, 153, 177–191. [Google Scholar] [CrossRef]
  9. Maulana, A.; Watanabe, K.; Imai, A.; Yonezu, K. Origin of magnetite-and llmenite-series granitic rocks in Sulawesi, Indonesia: Magma genesis and regional metallogenic constraint. Procedia Earth Planet. Sci. 2013, 6, 50–57. [Google Scholar] [CrossRef] [Green Version]
  10. Huang, L.C.; Jiang, S.Y. Highly fractionated S-type granites from the giant Dahutang tungsten deposit in Jian gnan Orogen, Southeast China: Geochronology, petrogenesis and their relationship with W-mineralization. Lithos 2014, 202–203, 207–226. [Google Scholar] [CrossRef]
  11. Wood, S.A.; Samson, I.M. The hydrothermal geochemistry of tungsten in granitoid environments: I. Relative solubilities of ferberite and scheelite as a function of T, P, PH, and NaCl. Econ. Geol. 2000, 95, 143–182. [Google Scholar] [CrossRef] [Green Version]
  12. Landtwing, M.R.; Pettke, T.; Halter, W.E.; Heinrich, C.A.; Redmond, P.B.; Einaudi, M.T.; Karsten, K. Copper deposition during quartz dissolution by cooling magmatic–hydrothermal fluids: The bingham porphyry. Earth Planet. Sci. Lett. 2005, 235, 229–243. [Google Scholar] [CrossRef]
  13. Klemm, L.M.; Pettke, T.; Heinrich, C.A.; Campos, E. Hydrothermal evolution of the El Teniente Deposit, Chile: Porphyry Cu-Mo ore deposition from low-salinity magmatic fluids. Econ. Geol. 2007, 102, 1021–1045. [Google Scholar] [CrossRef]
  14. Jiang, X.M. The activity characteristics and metallogenic significance of the Neopaleozoic intrusions in the Eastern Alatao mountains, XinJiang. Ph.D. Thesis, China University of Geosiences, Beijing, China, 2015. [Google Scholar]
  15. Cook, S.S. Supergene copper mineralization at the lakeshore mine, pinal county, Arizona. Econ. Geol. 1988, 83, 297–309. [Google Scholar] [CrossRef]
  16. Selby, D.; Nesbitt, B.E. Chemical composition of biotite from the casino porphyry cu–au–mo mineralization, yukon, canada: Evaluation of magmatic and hydrothermal fluid chemistry. Chem. Geol. 2000, 171, 77–93. [Google Scholar] [CrossRef]
  17. Stone, D. Temperature and pressure variations in suites of archean felsic plutonic rocks, berens river area, northwest superior province, ontario, canada. Can. Mineral. 2000, 38, 455–470. [Google Scholar] [CrossRef] [Green Version]
  18. Yavuz, F. Evaluating micas in petrologic and metallogenic aspect: I–definitions and structure of the computer program mica. Comput. Geosci. 2003, 29, 1203–1213. [Google Scholar] [CrossRef]
  19. Amr, A.; Mustafa, K.; Basem, Z.; Huseyin, Y. Evolution of the Tepeoba porphyry-skarn Cu-Mo-Au deposit, NW Turkey: New mineralogical and geochemical findings. Ore Geol. Rev. 2022, 147, 104967. [Google Scholar]
  20. Wang, Z.L.; Zhang, X.; Liu, Q.Q.; Shao, Y.J.; Wu, S.C.; Pan, M.; Chen, M.; Zhang, Y.C.; Wu, H.H. Genesis of the Lishupo gold deposit in the Jiangnan Orogen, NE Hunan (South China): Biotite Ar-Ar, zircon U-Pb ages and H-O-S-Pb isotopic constraints. Ore Geol. Rev. 2022, 145, 104890. [Google Scholar] [CrossRef]
  21. Kranidiotis, P.; Maclean, W.H. Systematics of chlorite alteration at the phelps dodge massive sulfide deposit, matagami, quebec. Econ. Geol. 1987, 82, 1898–1911. [Google Scholar] [CrossRef]
  22. Jowett, C. Fitting Iron and Magnesium into the Hydrothermal Chlorite Geothermometer; Geological Association of Canada: Waterloo, ON, Canada, 1991. [Google Scholar]
  23. Wang, E.D.; Song, K.; Yao, Y.Z.; Fu, J.F.; Hao, D.H.; Ma, S.S. Hyperspectral and Geochemical Analysis of Chlorites at the Gongchangling High-Grade Magnetite Deposit, NE China: Implications for Alteration Processes. Minerals 2022, 12, 629. [Google Scholar] [CrossRef]
  24. Xue, Q.W.; Wang, R.; Liu, S.Y.; Shi, W.X.; Tong, X.S.; Li, Y.Y.; Sun, F. Significance of chlorite hyperspectral and geochemical characteristics in exploration: A case study of the giant Qulong porphyry Cu-Mo deposit in collisional orogen, Southern Tibet. Ore Geol. Rev. 2022, 134, 104156. [Google Scholar] [CrossRef]
  25. Yuguchi, T.; Sasao, E.; Ishibashi, M.; Nishiyama, T. Hydrothermal chloritization processes from biotite in the toki granite, central japan: Temporal variations of of the compositions of hydrothermal fluids associated with chloritization. Am. Mineral. 2015, 100, 1134–1152. [Google Scholar] [CrossRef]
  26. Parsapoor, A.; Khalili, M.; Tepley, F.; Maghami, M. Mineral chemistry and isotopic composition of magmatic, re-equilibrated and hydrothermal biotites from darreh-zar porphyry copper deposit, kerman (Southeast of Iran). Ore Geol. Rev. 2015, 66, 200–218. [Google Scholar] [CrossRef]
  27. Zhou, Y.Q.; Wang, K.R. Basic characteristics and genesis of Zuluhong granitic body in North Xinjiang. Acta Petrol. Sin. 1993, 9, 72–78. [Google Scholar]
  28. Cao, R.; Bagas, L.; Chen, B.; Wang, Z.Q.; Gao, Y.B. Geochronology and petrogenesis of the composite Zuluhong Granite, North Xinjiang Province of China: Implications for the crust-mantle interaction and continental crustal growth in Western Tianshan Orogen. Lithos 2021, 380–381, 105837. [Google Scholar] [CrossRef]
  29. Jahn, B.M.; Wu, F.Y.; Chen, B. Granitoids of the central asian orogenic belt and continental growth in the phanerozoic. Trans. R. Soc. Edinb. Earth Sci. 2000, 91, 181–193. [Google Scholar]
  30. Lin, W.W.; Peng, L.J. The Estimation of Fe3+ and Fe2+ contents in amphibole and biotite from EMPA data. J. Jilin Univ. 1994, 24, 155–162. [Google Scholar]
  31. Yuan, W.M.; Liu, K.Q. A fortran program for calculation of the Fe3+ and Fe2+ contents in six kinds of minerals form electron—probe analysis data. J. Hebei GEO Univ. 1995, 18, 319–327. [Google Scholar]
  32. Foster, M.D. Interpretation of the composition of trioctahedral micas. US Geol. Surv. Prof. Pap. 1960, 354, 1–49. [Google Scholar]
  33. Deer, W.A. Rock-forming minerals. Longmans 1962, 1, 332–379. [Google Scholar]
  34. Inoue, A. Formation of Clay Minerals in Hydrothermal Environments. Origin and Mineralogy of Clays; Veldel, B., Ed.; Springer: Berlin/Heidelberg, Germany, 1995; pp. 673–796. [Google Scholar]
  35. Pan, Y.N.; Dong, G.C.; Li, X.F.; Wan, P. Biotite mineral chemistry and their implications for petrogenesis and mineralization in the prophyry copper deposit belt in northwest Yuannan. Earth Sci. Front. 2017, 24, 194–207. [Google Scholar]
  36. Bea, F.; Pereir, M.D.; Stroh, A. Mineral/leucosome trace element partitioning in a peraluminous migmatite (a laser ablation-icp-ms study). Chem. Geol. 1994, 117, 291–312. [Google Scholar] [CrossRef]
  37. Wones, D.R. Stability of biotite: Experiment, theory, and application. Am. Mineral. 1965, 50, 1228–1272. [Google Scholar]
  38. Cathelineau, M.; Nieva, D. A chlorite solid solution geothermometer the los azufres (Mexico) geothermal system. Contrib. Mineral. Petrol. 1985, 91, 235–244. [Google Scholar] [CrossRef]
  39. Nieto, F. Chemical composition of metapelitic chlorites: X-ray diffraction and optical property approach. Eur. J. Mineral. 1997, 9, 829–841. [Google Scholar] [CrossRef] [Green Version]
  40. Battaglia, F. Applying x-ray geothermometer diffraction to a chlorite. Clays Clary Miner. 1999, 47, 54–63. [Google Scholar] [CrossRef]
  41. Inoue, A.; Inoue, S.; Utada, M. Application of chlorite thermometry to estimation of formation temperature and redox conditions. Clay Miner. 2018, 53, 143–158. [Google Scholar] [CrossRef]
  42. Nishimoto, S.; Yoshida, H. Hydrothermal alteration of deep fractured granite: Effects of dissolution and precipitation. Lithos 2010, 115, 153–162. [Google Scholar] [CrossRef]
  43. Maydagán, L.; Franchini, M.; Impiccini, A.; Lentz, D. Phyllosilicates geochemistry and distribution in the altar porphyry cu-(au) deposit, andes cordillera of san juan, argentina: Applications in exploration, geothermometry, and geometallurgy. J. Geochem. Explor. 2016, 167, 83–109. [Google Scholar] [CrossRef]
  44. Walshe, J.L. A six-component chlorite solid solution model and the conditions of chlorite formation in hydrothermal and geothermal systems. Econ. Geol. 1986, 81, 681–703. [Google Scholar] [CrossRef]
  45. Speer, J.A. Micas in igneous rocks. Rev. Mineral. Geochem. 1984, 13, 299–356. [Google Scholar]
  46. Xie, X.G.; Byerly, G.R.; Ferrell, R.E. IIb trioctahedral chlorite from the Barberton greenstone belt: Crystal structure and rock composition constraints with implications to geothermometry. Contrib. Mineral. Petrol. 1997, 126, 275–291. [Google Scholar] [CrossRef]
  47. Albuquerque, C.A.R.D. Geochemistry of biotites from granitic rocks, northern portugal. Geochim. Et Cosmochim. Acta 1973, 37, 1779–1802. [Google Scholar] [CrossRef]
  48. Hu, J.; Qiu, J.Y.; Wang, R.C.; Jiang, S.Y.; Lin, H.F.; Wang, X.L. Zircon U-Pb geochronology, biotite mineral chemistry and their petrogenetic implications of the Longtwo and Baishigang plutons in Guangdong province. Acta Petrol. Sin. 2006, 22, 2464–2474. [Google Scholar]
  49. Spear, F.S.; Florence, F.P. Thermobarometry in granulites: Pitfalls and new approaches. Precambrian Res. 1992, 55, 209–241. [Google Scholar] [CrossRef]
  50. Roda, E.; Keller, P.; Pesquera, A.; Fontan, F. Micas of the muscovite–lepidolite series from Karibib Pegmatites, Namibia. Mineral. Mag. 2007, 71, 41–62. [Google Scholar] [CrossRef]
  51. Ishihara, S. The magnetite-series and ilmenite-series granitic rocks. Min. Geol. 1977, 27, 293–305. [Google Scholar]
  52. Geng, H.; Sun, M.; Yuan, C.; Xiao, W.; Xian, W.; Zhao, G.C.; Zhang, L.F.; Won, G.K.; Wu, F.Y. Geochemical, Sr–Nd and zircon U–Pb–Hf isotopic studies of late carboniferous magmatism in the west Junggar, Xinjiang: Implications for ridge subduction? Chem. Geol. 2009, 266, 364–389. [Google Scholar] [CrossRef]
  53. Zen, E. Aluminum enrichment in silicate melts by fractional crystallization: Some mineralogic and petrographic constraints. Jour Pet. 1986, 27, 1095–1117. [Google Scholar] [CrossRef]
  54. Chappell, B.W. Aluminium saturation in I- and S-type granites and the characterization of fractionated haplogranites. Lithos 1999, 46, 535–551. [Google Scholar] [CrossRef]
  55. Gao, P.D. A geochemical study of Mesozoic granites from the Nanling Range in South China. Ph.D. Thesis, University of Science and Technology of China, Hefei, China, 2016. [Google Scholar]
  56. Zhou, Z.X. The origin of intrusive mass in fengshandong, HuBei province. Acta Petrol. Sin. 1986, 2, 61–72. [Google Scholar]
  57. Li, Y.J.; Li, Z.C.; Zhou, J.B.; Gao, Z.H.; Gao, Y.L.; Tong, L.M. Division of Carboniferous lithostratigraphic units in Awulale, Western TianShan. Acta Petrol. Sin. 2009, 25, 1332–1340. [Google Scholar]
  58. Xue, X.Y.; Xia, L.Q.; Ma, Z.P.; Wang, Y.B.; Xia, C.Z.; Li, X.M. SHRIMP zircon geochronology of the palgiogranites from Bayingou ophiolite in North TianShan Mountains and the petrogenesis of the ophiolite. Acta Petrol. Sin. 2006, 22, 83–94. [Google Scholar]
  59. Zhao, K.D.; Jiang, S.Y.; Jiang, Y.H.; Wang, R.C. Mineral chemistry of the qitianling granitoid and the furong tin oredeposit in hunan province, south china. Eur. J. Mineral. 2005, 17, 635–648. [Google Scholar] [CrossRef]
  60. Sisson, T.W.; Ratajeski, K.; Hankins, W.B.; Glazner, A.F. Voluminous granitic magmas from common basaltic sources. Contrib. Mineral. Petrol. 2005, 148, 635–661. [Google Scholar] [CrossRef]
  61. Keppler, H.; Wyllie, P.J. Partitioning of Cu, Sn, Mo, W, U, and Th between melt and aqueous fluid in the system haplogranite-H2O HCl and haplogranite-H2O-HF. Contrib. Mineral. Petrol. 1991, 109, 139–150. [Google Scholar] [CrossRef]
  62. Mao, Z.H.; Cheng, Y.B.; Liu, J.J.; Yuan, S.D.; Wu, S.H.; Xiang, X.K.; Luo, X.H. Geology and molybdenite Re-Os age of the Dahutang granite-related veinlets-disseminated tungsten ore field in the Jiangxin Province, China. Ore Geol. Rev. 2013, 53, 422–433. [Google Scholar] [CrossRef]
  63. Huang, H.L.; Chang, H.L.; Tan, J.; Li, F.; Zhang, C.H.; Zhou, Y. Contrasting infrared microthermometry study of fluid inclusions in coexisting quartz, wolframite and other minerals: A case study of Xihuashan quartz-vein tungsten deposit, China. Acta Petrol. Sin. 2015, 31, 925–940. [Google Scholar]
  64. Chen, J.; Wang, R.C.; Zhu, J.C. Multiple-aged granitoids and related tungsten-tin mineralization in the Nanling Range, South China. Sci. China Earth Sci. 2013, 56, 2045–2055. [Google Scholar] [CrossRef]
  65. Hua, R.M.; Li, G.L.; Zhang, W.L.; Hu, D.Q.; Chen, P.R.; Chen, W.F.; Wang, X.D. A tentative discussion on differences between large-scale tungsten and tin mineralizations in South China. Miner. Depos. 2001, 29, 9–23. [Google Scholar]
  66. Hu, R.Z.; Bi, X.W.; Turner, G.; Burnard, P.G. He-Ar isotope system of pyrite fluid inclusions in the Chang Qing copper deposit. Science in China (Series D). Sci. China 1997, 27, 503–508. [Google Scholar]
  67. Li, G.L.; Hua, R.M.; Wei, X.G.; Wang, X.D.; Huang, X. Rb-Sr isochron age of single-grain muscovite in the Xushan W-Cu deposit, central Jiangxi, and its geological significance. Earth Sci. J. China Univ. Geosci. 2011, 36, 282–288. [Google Scholar]
  68. Wang, X.G.; Liu, Z.Q.; Liu, S.B.; Wang, C.H.; Liu, J.G.; Wan, H.Z. LA-ICP-MS Zircon U-Pb Dating and Petrologic Geochemistry of Finegrained Granite from Zhuxi Cu-W Deposit, Jiangxi Province and its Geological Significance. Rock Miner. Anal. 2015, 34, 592–599. [Google Scholar]
  69. Pan, X.F.; Song, C.Y.; Wang, S.X.; Li, Z.Q.; Yang, M.Z.; Hou, Z.Q. Evolution of Hydrothermal Fluid of Dexing Tongchang Copper-gold Porphyry Deposit. Acta Geol. Sin. 2009, 83, 1929–1950. [Google Scholar]
  70. Wang, D.H.; Chen, Z.H.; Chen, Y.H.; Tang, J.X.; Li, J.K.; Ying, L.J. New Data of the Rock-Forming and Ore-Forming Chronology for China’s Important Mineral Resources Areas. Acta Geol. Sin. 2010, 84, 1030–1040. [Google Scholar]
  71. Xu, J.J.; Lai, Y.; Cui, D.; Chang, Y.; Jiang, Y.I.; Shu, Q.H.; Li, W.B. Characteristics and evolution of ore-forming fluids of the Daolundaba copper-poly-metal deposit, Inner Mongolia. Acta Petrol. Sin. 2009, 25, 2957–2972. [Google Scholar]
  72. Wang, H.; Feng, C.Y.; Li, D.X.; Xiang, X.K.; Zhou, J.H. Sources of granitoids and ore-forming materials of Dahutang tungsten deposit in northern Jiangxi Province: Constraints from mineralogy and isotopic tracing. Acta Petrol. Sin. 2015, 31, 725–739. [Google Scholar]
  73. Xiang, X.K.; Wang, P.; Zhan, G.N.; Sun, D.M.; Zhong, B.; Qian, Z.Y. Geological characteristics of Shimensi tungsten polymetallic deposit in northern Jiangxi Province. Miner. Depos. 2013, 32, 1171–1187. [Google Scholar]
  74. Xu, G.F. On the study of genetic significance of manganese-iron ratios in wolframite. Sci. Geol. Sin. 1981, 4, 390–394. [Google Scholar]
  75. Liu, Y.; Zhao, Y.Y.; Cui, Y.B.; Lv, L.N.; Nie, F.J. Characteristics of facieology and mineragraphy of copper polymetallic ore deposit in Shesuo, Tibet. Acta Petrol. Sin. 2011, 27, 2109–2131. [Google Scholar]
  76. Mengason, M.J.; Candela, P.A.; Piccoli, P.M. Molybdenum, tungsten and manganese partitioning in the system pyrrhotite-Fe-S-O melt-rhyolite melt: Impact of sulfide segregation on arc magma evolution. Geochim. Et Cosmochim. Acta 2011, 75, 7018–7030. [Google Scholar] [CrossRef]
  77. Che, X.D.; Linnen, R.L.; Wang, R.C. Tungsten solubility in evolved granitic melts: An evaluation of magmatic wolframite. Geochmica Et Cosmochim. Acta 2013, 106, 84–98. [Google Scholar] [CrossRef]
  78. Chen, Z.L.; Peng, S.L. the experimental results of W and Sn Partitioning between fluid and melt and their significance for the origin of W and Sn ore deposits. Geol. Rev. 1994, 40, 274–282. [Google Scholar]
Minerals 12 01280 g001 550
Figure 1. Geological sketch map of the Central Asian Orogenic Belt in the Alatau area and the Zuluhong W–Cu deposit, showing (a) the location of the Central Asian Orogenic Belt (modified after Jahn et al. [29]), (b) the location of the Zuluhong and northwest Tianshan metallogenic belt, and (c) the distribution of stratigraphic units and major structures in the Zuluhong W–Cu deposit.
Figure 1. Geological sketch map of the Central Asian Orogenic Belt in the Alatau area and the Zuluhong W–Cu deposit, showing (a) the location of the Central Asian Orogenic Belt (modified after Jahn et al. [29]), (b) the location of the Zuluhong and northwest Tianshan metallogenic belt, and (c) the distribution of stratigraphic units and major structures in the Zuluhong W–Cu deposit.
Minerals 12 01280 g001
Minerals 12 01280 g002 550
Figure 2. Typical examples of mineralized quartz veins in the Zuluhong deposit. (a) Platy wolframite (2–5 cm across) in an early quartz vein. (b) Smooth contact between wolframite and quartz (plane-polarized light). (c) Chalcopyrite replacing wolframite and infilling cleavage planes. (d) Chalcopyrite replacing wolframite in a late quartz vein (plane-polarized light). (e) Pyrite replacing wolframite in a late quartz vein. (f) Pyrite infilling voids and cleavage planes, surrounded by quartz (plane-polarized light). Ccp = chalcopyrite; Py = pyrite; Q = quartz; Wol = wolframite.
Figure 2. Typical examples of mineralized quartz veins in the Zuluhong deposit. (a) Platy wolframite (2–5 cm across) in an early quartz vein. (b) Smooth contact between wolframite and quartz (plane-polarized light). (c) Chalcopyrite replacing wolframite and infilling cleavage planes. (d) Chalcopyrite replacing wolframite in a late quartz vein (plane-polarized light). (e) Pyrite replacing wolframite in a late quartz vein. (f) Pyrite infilling voids and cleavage planes, surrounded by quartz (plane-polarized light). Ccp = chalcopyrite; Py = pyrite; Q = quartz; Wol = wolframite.
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Minerals 12 01280 g003 550
Figure 3. Photomicrographs of different biotite types from the Zuluhong monzogranite. (a) Unaltered biotite. (b,c) Partially altered biotite. (d) Biotite completely replaced by chlorite (Ap = apatite; Bi = biotite; Chl = chlorite; Pl = plagioclase; Q = quartz). All of the photomicrographs are in plane-polarized light.
Figure 3. Photomicrographs of different biotite types from the Zuluhong monzogranite. (a) Unaltered biotite. (b,c) Partially altered biotite. (d) Biotite completely replaced by chlorite (Ap = apatite; Bi = biotite; Chl = chlorite; Pl = plagioclase; Q = quartz). All of the photomicrographs are in plane-polarized light.
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Minerals 12 01280 g004 550
Figure 4. Compositional plots for biotite and chlorite. (a) Compositional plot for biotite, showing that the data fall in the Fe-biotite field (modified after Foster, [32]). (b) Compositional plot for chlorite, showing that the data fall in the ripidolite field (modified after Deer, [33]).
Figure 4. Compositional plots for biotite and chlorite. (a) Compositional plot for biotite, showing that the data fall in the Fe-biotite field (modified after Foster, [32]). (b) Compositional plot for chlorite, showing that the data fall in the ripidolite field (modified after Deer, [33]).
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Minerals 12 01280 g005 550
Figure 5. Rare earth and trace element patterns of the Zuluhong monzogranite and biotite. (a) Chondrite-normalized rare earth element patterns. (b) Primitive-mantle-normalized trace element patterns [28].
Figure 5. Rare earth and trace element patterns of the Zuluhong monzogranite and biotite. (a) Chondrite-normalized rare earth element patterns. (b) Primitive-mantle-normalized trace element patterns [28].
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Minerals 12 01280 g006 550
Figure 6. Fe3+–Fe2+–Mg diagram for biotite (modified after Wones et al. [37]).
Figure 6. Fe3+–Fe2+–Mg diagram for biotite (modified after Wones et al. [37]).
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Minerals 12 01280 g007 550
Figure 7. Biotite Fe3+/Fe2+ ratio versus major element oxides. (a) the negative relationships between Fe3+/Fe2+ and FeO. (b) the negative relationships between Fe3+/Fe2+ and MgO. (c) the negative relationships between Fe3+/Fe2+ and Al2O3. (d) the positive relationship between Fe3+/Fe2+ and TiO2.
Figure 7. Biotite Fe3+/Fe2+ ratio versus major element oxides. (a) the negative relationships between Fe3+/Fe2+ and FeO. (b) the negative relationships between Fe3+/Fe2+ and MgO. (c) the negative relationships between Fe3+/Fe2+ and Al2O3. (d) the positive relationship between Fe3+/Fe2+ and TiO2.
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Figure 8. (a) Microphotograph of the biotite. (b) EDX map of the biotite, which exhibits heterogeneous composition.
Figure 8. (a) Microphotograph of the biotite. (b) EDX map of the biotite, which exhibits heterogeneous composition.
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Minerals 12 01280 g009 550
Figure 9. Major element variation diagrams for igneous biotite. (a) The MgO content of igneous biotite increases from the Point 1 to Point 5. (b) The FeO content of igneous biotite decreases from the Point 1 to Point 5. (c) The TiO2 content of igneous biotite increases from the Point 1 to Point 5. (d) The (Na2O + K2O) content of igneous biotite increases from the Point 1 to Point 5. (e) The Al2O3 content of igneous biotite increases from the Point 1 to Point 5. (f) The CaO content of igneous biotite increases from the Point 1 to Point 5. 1 = Point 1 of Figure 8 and 5 = Point 5 of Figure 8.
Figure 9. Major element variation diagrams for igneous biotite. (a) The MgO content of igneous biotite increases from the Point 1 to Point 5. (b) The FeO content of igneous biotite decreases from the Point 1 to Point 5. (c) The TiO2 content of igneous biotite increases from the Point 1 to Point 5. (d) The (Na2O + K2O) content of igneous biotite increases from the Point 1 to Point 5. (e) The Al2O3 content of igneous biotite increases from the Point 1 to Point 5. (f) The CaO content of igneous biotite increases from the Point 1 to Point 5. 1 = Point 1 of Figure 8 and 5 = Point 5 of Figure 8.
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Figure 10. (a) Granite source discrimination diagram (modified after Zhou, [56]). (b) Biotite Mg# versus A/CNK diagram (modified after Gao, [55]).
Figure 10. (a) Granite source discrimination diagram (modified after Zhou, [56]). (b) Biotite Mg# versus A/CNK diagram (modified after Gao, [55]).
Minerals 12 01280 g010
Table
Table 1. Major (wt.%) element data of the unaltered and partially altered biotites in Zuluhong granite.
Table 1. Major (wt.%) element data of the unaltered and partially altered biotites in Zuluhong granite.
SampleU2911U2912U2921U2922U2923U2924U2925U2926U2927U29211
Major element (wt.%)
SiO235.6035.5234.8834.9235.5034.4434.4435.2734.5035.96
TiO22.282.312.132.342.372.342.282.312.222.28
Al2O315.2815.2814.9215.0215.0714.6815.0014.6314.3915.58
FeO25.1624.9725.2525.5325.3825.2425.7525.4924.9225.77
MnO0.490.490.540.480.500.520.520.570.480.47
MgO6.866.927.036.896.596.906.726.907.066.57
CaO0.090.040.020.040.030.090.060.100.070.01
Na2O0.100.090.000.090.070.130.090.110.110.07
K2O9.389.349.729.649.669.329.509.529.529.80
Total95.2494.9694.5494.9595.1693.6594.3794.9093.2796.51
Number of ions on the basis of 22 oxygens
Si2.812.812.792.782.812.782.762.812.792.81
AlⅣ1.191.191.211.221.191.221.241.191.211.19
Ti0.140.140.130.140.140.140.140.140.140.13
Fe3+0.170.180.120.130.160.130.120.140.120.16
Fe2+1.491.471.571.571.521.571.611.561.571.52
Mn0.030.030.040.030.030.040.040.040.030.03
Mg0.810.810.840.820.780.830.800.820.850.76
Ca0.010.000.000.000.000.010.010.010.010.00
Na0.020.010.010.010.010.020.010.020.020.01
K0.940.940.990.980.980.960.970.970.980.98
Total7.837.827.887.877.847.877.887.867.887.84
Fe3+/2+0.120.120.070.080.110.080.070.090.070.11
Mg#0.530.530.530.520.510.530.520.520.540.51
A/CNK1.461.481.411.411.401.421.371.351.492.45
BufferNNONNONNONNONNONNONNONNONNONNO
SampleP29210P2931P2932P2933P2934P2935P2936P2937P2938P2939P29310
Major element (wt.%)
SiO225.1323.4525.4023.1924.7824.7724.4224.2933.1625.1925.61
TiO20.180.130.171.460.100.180.130.092.390.090.12
Al2O320.9819.5817.7918.9520.2419.9720.5820.4313.6820.4020.34
FeO33.5932.9831.8732.9232.9633.1032.7832.8722.5534.7734.48
MnO0.720.560.370.590.600.480.630.670.511.130.98
MgO8.649.6910.018.918.909.239.138.626.257.357.55
CaO0.010.040.070.030.020.020.010.010.000.000.00
Na2O0.010.060.060.030.010.050.030.050.110.010.04
K2O0.300.020.330.090.070.180.210.039.150.090.08
Total89.5686.5186.0786.1887.6887.9887.9187.0387.8089.0489.19
Number of ions on the basis of 22 oxygens
Si2.242.072.152.142.112.122.842.172.192.142.08
AlⅣ1.761.931.851.861.891.881.161.831.811.861.92
AlⅥ0.090.050.220.180.210.230.210.240.250.240.12
Ti0.010.100.010.010.010.010.150.010.010.010.01
Fe3+0.150.150.180.160.160.180.170.210.220.180.10
Fe2+2.202.302.212.242.212.231.442.302.252.212.34
Mn0.030.040.040.040.050.050.040.080.070.050.04
Mg1.321.181.151.191.181.120.800.940.961.091.28
Ca0.010.000.000.000.000.000.000.000.000.000.00
Na0.010.010.000.010.000.010.020.000.010.000.01
K0.040.010.010.020.020.001.000.010.010.030.00
Total7.857.857.827.847.847.827.837.797.787.827.90
Fe3+/2+0.070.070.080.070.070.080.120.090.100.080.04
Mg#0.510.550.560.530.520.530.530.520.530.460.47
A/CNK56.9497.2731.2494.18156.4163.9471.31167.431.35163.88133.84
BufferFMQFMQFMQFMQFMQFMQFMQFMQFMQFMQFMQ
U = Unaltered Biotite; P= Partially Altered Biotites; Mg# = molar Mg/(Mg + Fe); A/CNK = molar Al2O3/(CaO + Na2O + K2O); Fe3+/2+ = molar Fe3+/Fe2+; buffer = the oxygen buffer; “/” represents that the Ti content of partially altered biotites is below limit and the oxygen buffer cannot be estimated.
Table
Table 2. LA-ICP-MS Analysis result data of magmatic biotites in the Zuluhong granite.
Table 2. LA-ICP-MS Analysis result data of magmatic biotites in the Zuluhong granite.
SampleZ331Z332Z333Z334Z335Z336Z3311Z3312Z3312Z3313Z3314
Trace element (ppm.)
Li638.14440.45451.24536.22693.73333.63595.63563.42587.53540.43600.71
V238.17355.5309.87295.94286.91185.76267.59311.62289.39288.97253.91
Cr32.3529.6528.8853.3538.2826.1747.6860.9856.9055.1235.81
B1.012.864.761.212.160.000.090.001.410.242.26
Sc64.4374.5960.3663.1360.5533.2167.8969.8669.1870.7565.43
Co33.0843.3040.9338.4933.3927.6035.3237.1037.4136.3234.60
Ni20.9025.6626.1122.3115.3918.2226.9226.7726.8827.0823.35
Cu1.517.625.8512.501.406.432.890.361.240.290.60
Zn716.651005.351001.45859.73719.19604.10653.67624.31673.23720.86769.59
Ga65.3789.4284.8074.6862.9655.6858.8760.7963.4962.8461.49
Rb977.18241.28437.40779.901094.261067.27542.97611.72637.47762.52794.84
Sr1.382.472.097.141.084.61754.028.760.880.340.97
Y0.591.370.596.290.631.772.510.330.520.051.19
Zr0.450.460.722.220.4023.030.660.182.180.080.23
Nb122.3828.1439.6396.00136.0470.3078.8282.6989.38106.54130.31
Mo0.090.000.280.420.000.350.560.340.150.240.09
Sn74.1617.3224.0944.2274.9380.4466.5060.9266.2869.1079.93
Cs52.1528.81105.2868.6257.57167.7729.1918.9615.7820.6827.04
SampleZ331Z332Z333Z334Z335Z336Z3311Z3312Z3312Z3313Z3314
Trace element (ppm.)
Ba1130.20229.0534.8780.07894.13140.052000.64575.74677.56397.511500.49
La0.170.350.391.420.111.610.860.050.110.020.17
Ce0.170.640.601.990.263.340.230.030.160.010.14
Pr0.060.130.110.720.020.740.240.010.050.000.05
Nd0.250.830.552.70.282.231.260.070.140.030.24
Sm0.080.180.170.980.080.790.250.010.060.000.22
Eu0.000.020.030.040.020.140.060.020.000.020.06
Gd0.050.300.081.110.040.310.360.000.010.000.20
Tb0.010.020.010.220.040.060.030.000.010.000.02
Dy0.110.240.151.300.090.460.350.060.060.020.14
Ho0.010.030.020.250.040.110.060.010.020.000.05
Er0.080.170.070.440.040.040.350.040.070.000.12
Tm0.010.010.000.080.030.000.030.010.010.000.02
Yb0.040.190.1410.600.080.230.240.030.090.020.14
Lu0.010.010.020.070.030.010.020.000.010.010.01
Hf0.030.040.070.060.061.330.040.000.240.010.04
Ta22.065.087.9618.7625.9610.905.955.116.3611.1828.72
W0.970.340.611.090.970.650.420.610.750.990.86
Pb3.6410.7912.4817.193.177.726.072.763.722.283.33
Th0.070.641.232.130.002.280.030.020.140.000.01
U0.020.160.270.880.000.620.030.000.030.010.01
ΣREE1.043.122.3211.931.1710.084.350.3570.800.131.57
LREE0.722.141.847.850.778.862.900.190.530.080.87
HREE0.320.980.494.080.391.221.450.160.280.050.70
L/H2.252.203.751.931.937.241.991.201.901.681.26
L/Y2.711.341.961.691.044.982.500.970.950.490.87
δEu0.930.240.780.110.990.720.624.040.584.460.92
δCe0.430.730.710.481.170.750.120.390.500.390.36
L/H = LREE/HREE; L/Y = LaN/YbN.
Table
Table 3. Major (wt.%) element data of the chlorites in Zuluhong granite (during ore formation).
Table 3. Major (wt.%) element data of the chlorites in Zuluhong granite (during ore formation).
SampleC1C3C4C5C6C7C8C9C10C11C12C13C15
Major element (wt.%)
SiO225.9526.3624.9924.9225.1525.1025.0925.0624.7324.3324.5523.9223.81
TiO20.020.050.020.030.060.080.000.000.010.000.020.010.11
Al2O315.4815.8620.1920.3520.1319.8220.9920.3720.3220.0619.7119.3819.23
FeO36.3732.9829.8229.3229.3929.7029.7530.3930.7829.7030.2129.3129.46
MnO0.650.560.530.560.560.530.610.660.620.600.630.600.63
MgO6.718.869.969.549.339.869.219.419.399.919.429.9110.43
CaO0.000.030.020.030.060.080.090.040.070.070.070.100.15
Na2O0.050.070.060.120.120.120.130.050.050.040.040.060.09
K2O0.010.050.050.100.060.060.040.010.040.000.010.040.02
Cr2O30.020.030.010.060.040.050.140.000.020.050.050.280.08
Total85.2684.8585.6485.0484.8985.4186.0585.9786.0384.7484.7083.6184.00
Number of ions on the basis of 14 oxygens
Si3.023.022.782.782.812.802.772.782.752.742.772.742.71
AlⅣ0.980.981.221.221.191.201.231.221.251.261.231.261.29
AlⅥ1.141.161.421.461.471.401.501.441.421.401.391.351.30
Ti0.0020.0040.0020.0030.0050.0070.000.000.0010.000.0020.0010.009
Cr0.0020.030.0010.0050.0040.0040.0120.000.0020.0040.0050.0250.007
Fe2+3.543.162.772.742.752.772.752.822.862.792.852.802.81
Mn0.060.050.050.050.050.050.060.060.060.060.060.060.06
Mg1.161.511.651.591.561.641.521.561.561.661.591.691.77
Ca0.0000.0040.0020.0040.0070.0100.0110.0050.0080.0080.0080.0120.018
Na0.0110.0150.0130.0260.0260.0260.0280.0110.0110.0090.0090.0130.020
K0.0020.0070.0070.0140.0090.0090.0060.0010.0060.0000.0010.0060.003
Total9.929.929.919.909.879.919.889.909.929.939.929.959.99
Mg#0.430.520.580.570.560.560.560.550.580.560.580.590.56
lg(fO2)−43.58−44.08−39.93−40.05−40.57−39.84−39.93−39.42−39.33−39.78−39.25−38.85−40.48
T(°C)230.82222.31264.64239.62224.75246.69231.12253.31270.39282.87264.92278.56302.34
C = Chlorite; Mg# = molar Mg/(Mg + Fe); T(°C) = Centigrade temperature.
Table
Table 4. Major (wt.%) and trace (×10−6) element data of the Zuluhong granite.
Table 4. Major (wt.%) and trace (×10−6) element data of the Zuluhong granite.
SimpleZLH-29ZLH-30ZLH-31ZLH-33ZLH-34ZLH-26ZLH-27ZLH-1ZLH-2
Major element (wt.%)
SiO272.7073.2274.0374.4173.7763.7264.1265.3064.38
TiO20.330.280.290.260.300.610.610.580.60
Al2O313.4413.5313.1813.1413.6215.9815.9916.0115.99
MnO0.070.060.060.060.060.100.100.100.10
MgO0.620.510.560.490.592.492.532.272.43
CaO1.741.601.591.421.694.414.614.034.35
Na2O3.623.553.373.453.613.833.783.723.78
K2O3.683.994.003.943.822.262.302.602.39
P2O50.100.090.090.070.090.200.200.180.19
TFe2O32.542.102.252.132.314.194.433.384.00
LOI0.540.360.440.490.461.381.141.411.31
Mg#323233333254535754
A/CNK1.031.041.031.051.040.950.940.980.96
Na2O/K2O0.980.890.840.880.951.691.641.431.58
Trace elements (10−6)
La26.5028.2022.722.0027.4019.4018.5021.3019.73
Ce66.4063.7058.155.8062.3044.7041.1046.3044.0
Pr6.907.276.006.007.145.305.045.605.31
Nd26.1027.3022.622.7026.9021.3020.0021.9021.61
Sm5.645.614.865.085.534.093.964.294.11
Eu0.690.720.660.570.681.071.031.071.06
Dy4.023.493.893.914.222.772.672.922.79
Y19.4017.4020.7019.2021.9015.1014.6015.9015.20
Ho0.760.660.770.720.830.560.550.590.57
Yb1.871.752.051.932.191.391.381.491.42
Lu0.310.280..340.330.370.240.240.260.25
Rb16617417317316468739679
Ba260260270200250510500510507
Th18.2517.8514.7017.7517.857.506.938.757.73
U3.303.902.103.803.802.402.802.602.6
Ta1.241.281.151.601.140.520.510.570.53
Nb8.807.807.709.208.205.305.305.505.37
Pb16.0018.8017.4019.0018.206.606.007.706.8
Sr155150146127150638629548605
P460390420350410940950820903
Zr91.890.375.786.684.4134.0135.5134.5134.7
Hf3.203.102.603.002.803.503.503.603.53
Ti206016901800160018303670375034903637
∑REE148.56140.40129.54131.59118.16106.45100.02111.68106.05
δEu0.020.020.430.010.020.080.080.070.84
LaN/YbN9.5810.897.487.708.459.439.069.669.39
Rb/Sr1.0741.1631.1891.3671.1000.1060.1160.1740.130
Sr/Y7.968.627.036.596.8342.2543.0834.4739.80
Note: Mg# = molar Mg/(Mg + Fe). Data from Cao et al. [28]. In summary, geochemical data suggest that the Zuluhong granite is a highly fractionated and weakly peraluminous I-type granite that was derived from the partial melting of lower crust.
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Cao, R.; Chen, D.-F.; Gu, H.-D.; Chen, B.; Yan, S.-C. Mineralogical Characteristics of Biotite and Chlorite in Zuluhong Polymetallic Deposit: Implications for Petrogenesis and Paragenesis Mechanisms of the Tungsten and Copper. Minerals 2022, 12, 1280. https://doi.org/10.3390/min12101280

AMA Style

Cao R, Chen D-F, Gu H-D, Chen B, Yan S-C. Mineralogical Characteristics of Biotite and Chlorite in Zuluhong Polymetallic Deposit: Implications for Petrogenesis and Paragenesis Mechanisms of the Tungsten and Copper. Minerals. 2022; 12(10):1280. https://doi.org/10.3390/min12101280

Chicago/Turabian Style

Cao, Rui, De-Fan Chen, Hao-Dong Gu, Bin Chen, and Sheng-Chao Yan. 2022. "Mineralogical Characteristics of Biotite and Chlorite in Zuluhong Polymetallic Deposit: Implications for Petrogenesis and Paragenesis Mechanisms of the Tungsten and Copper" Minerals 12, no. 10: 1280. https://doi.org/10.3390/min12101280

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