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Article

Genesis of Pb–Zn Mineralization in the Pulang Cu Polymetallic Deposit in Yunnan Province, China: Insights from Analyses of Geology, Fluid Inclusions and C–H–O–S Isotopes

by
Jingwei Xu
1,
Xiaoyu Zhao
1,*,
Mingguo Deng
1,*,
Wenchang Li
1 and
Yan Su
2
1
Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China
2
Yunnan Diqing Non-Ferrous Metals Co., Ltd., Diqing 674400, China
*
Authors to whom correspondence should be addressed.
Minerals 2024, 14(2), 176; https://doi.org/10.3390/min14020176
Submission received: 2 January 2024 / Revised: 31 January 2024 / Accepted: 4 February 2024 / Published: 6 February 2024
(This article belongs to the Section Mineral Deposits)
Browse Figures
Versions Notes

Abstract

:
The Pulang super-large porphyry Cu polymetallic deposit, located in the Sanjiang area of Yunnan Province, is one of the largest Cu deposits in China. This deposit hosts Cu resources of ~5 × 106 t and other ore-forming elements, such as Mo, Au, Ag, Pb, Zn, Pt and Pd. Recently, obvious hydrothermal vein-type Pb–Zn mineralization, with a Pb + Zn resource of ~0.4 × 106 t, has been detected in the North Ore Section of the deposit. However, the genesis of these Pb–Zn ore bodies, especially their relationship to the major Cu ore bodies in the South Ore Section, remains controversial. We conducted geologic description, fluid inclusion petrography and microthermometry, and C, H, O and S isotope studies to uncover the genesis of Pb–Zn vein-type mineralization in North Pulang. As a result, three types of Pb–Zn veins were identified: a quartz–pyrrhotite–chalcopyrite–sphalerite–galena vein, a quartz–pyrrhotite–sphalerite–galena vein, and a calcite–quartz–pyrrhotite–galena vein. All fluid inclusions in the quartz from different veins are liquid-rich inclusions, with homogenization temperatures in the range of 184 °C–235 °C and salinities between 10.4 wt.% and 17.8 wt.% NaCl eq., indicating that the Pb–Zn ore-forming fluid was a single-phase fluid with a low temperature and low-to-medium salinity. Hydrothermal quartz in different stages displays δDwater values ranging from −46.9‰ to −120.0‰ (V-SMOW), and the calculated δ18Owater values range from 2.4‰ to 4.3‰ (V-SMOW), implying that the mineralization fluids likely originated from magma, with a minor involvement of meteoric water. The δ13CCal values (−2.3‰ to −7.9‰ V-PDB) of calcite indicate that C likely originated from a deep-seated source. The δ34S values of chalcopyrite, pyrite, pyrrhotite and sphalerite reveal that S was possibly derived from magmatic rocks. Based on the above data, it is suggested that the Pb–Zn mineralization in North Pulang was the result of the northward migration of ore-forming fluids that originated from South Pulang along the NE-trending structural fractures. A strong water–rock interaction occurred during the migration process. However, the involvement of meteoric water and accompanied cooling of fluids were most likely responsible for the precipitation of galena and sphalerite.

1. Introduction

Porphyry deposits, as the main source of Cu and Mo metals and an important source of Au in the world [1,2,3], have long been a research focus in the field of ore deposits. Controlled by different tectonic activities, the southern part of the Yidun Island Arc (Geza volcano-magmatic arc [4]) in the Sanjiang area, Southwest China, developed a multi-stage superimposed magmatic-hydrothermal metallogenic system, including the Indosinian porphyry–skarn Cu polymetallic mineralization system, the Yanshanian porphyry Mo–Cu polymetallic mineralization system, and the Himalayan alkali-rich porphyry Au–Mo–Cu polymetallic mineralization system [5]. The Indosinian magmatic-hydrothermal mineralization is the most intense in this area. The westward subduction of the Triassic Ganzi–Litang Ocean generated a series of intermediate-acid magmatic rocks and associated porphyry and skarn deposits distributed from the south to the north [5]. These deposits can be further divided into the western Lannitang–Chundu metallogenic belt (the Xuejiping Cu deposit, Lannitang Cu deposit, Chundu Cu deposit, Are Cu deposit, etc.) and the eastern Yaza–Pulang metallogenic belt (Hongshan Cu–Mo deposit, Langdu Cu deposit, Pulang Cu deposit, etc.) [4,5].
The Pulang porphyry Cu polymetallic deposit (later referred to as the Pulang Cu deposit) is located south of the eastern Yaza–Pulang metallogenic belt, with major ore-forming elements of Cu, Mo, and Au and associated metals of Ag, Pb, Zn, Pt, and Pd [4,6]. According to the distribution of ore bodies, the Pulang deposit can be further divided into the South, East, and North Ore Sections. Many studies have been conducted on this deposit, including its geological characteristics [7,8,9,10], petrology and petrogeochemistry [9,10,11], diagenetic and metallogenic chronology [4,8,12], and ore-forming fluid evolution [5,6,13,14]. However, most studies are dedicated to solving the metallogenic mechanism of Cu, such as the origin of ore-forming materials and fluids, the transport and precipitation process of metals, and the relationship between structures and Cu mineralization [15,16,17,18,19,20]. Recent explorations have shown that the North Ore Section hosts several Pb–Zn ore bodies, with Pb + Zn metal resources of more than 0.4 × 106 t [19], suggesting a strong exploration potential. However, research on the genesis of Pb–Zn mineralization in this deposit is relatively scarce, which hinders our deep understanding of the Pulang porphyry metallogenic system and further prospecting in the periphery of the mining district. In this paper, the geological characteristics of Pb–Zn ore bodies in North Pulang are described in detail. On this basis, petrographic observation and microthermometry of fluid inclusions are carried out. Combined with the analytical results regarding C, H, O and S isotopes of different minerals, the properties and sources of ore-forming fluids and the sources of ore-forming materials are traced to reveal the Pb–Zn metallogenic process. The genetic relationship between Pb–Zn mineralization and the southern major Cu ore bodies is discussed to provide a theoretical foundation for the establishment of the Pulang porphyry Cu polymetallic system and peripheral prospecting and exploration.

2. Regional Geology

The Sanjiang area is located east of the Tethys tectonic domain and southeast of the Tibetan Plateau. The Palaeozoic and Mesozoic multistage closure and accretion of the Tethys Ocean and the complex orogeny caused by the Cenozoic India–Eurasia continental collision created an important polymetallic metallogenic province in China [21]. From east to west, the area consists of the Songpan–Ganzi, Lhasa, the Qiangtang massif, and the Yidun Island Arc spreading along the NNW–SSE direction (Figure 1a; [22,23,24]). The Yidun Island Arc was generated by the westward subduction of the Ganzi–Litang Ocean during the Late Triassic period. The Changtai Arc in the north displayed strong inter-arc tension due to its fast subduction speed and steep subduction angle. In contrast, the Zhongdian Arc in the south formed under a slow subduction speed and a low subduction angle, which resulted in a regional compression stress environment [4,12,25,26]. Controlled by plate subduction, the Yidun Island Arc developed large-scale magmatic activities in the Late Triassic [6,27,28], which were manifested as abundant granite, granodiorite, and monzogranite intruded into the Palaeozoic strata and volcanic-sedimentary rock sequences.
The southern part of the Yidun Island Arc is also known as the Zhongdian Arc, within which major calc-alkaline andesite and dacite are intruded by intermediate-acidic porphyrites that were formed slightly later, constituting a typical arc–volcanic–magmatic complex belt [29]. The Late Triassic volcano-sedimentary sequences of the Zhongdian Arc include the Qugasi Formation, the Tumugou Formation, and the Lamaya Formation from the bottom to the top [30]. The Qugasi Formation consists of dark grey slate, fine-grained quartz sandstone, limestone, and mafic volcanic rock, with a basement of conglomerates [12,31]. The Tumugou Formation consists of grey slate, sandstone, moderately acidic volcanic rock, tuffs, and a small amount of mafic volcanic rocks [32]. The lithology of the Lamaya Formation is mainly slate and quartz sandstone, which is in conformable contact with the underlying Tumugou Formation. Many porphyry and skarn deposits were generated by the intrusion of Indosinian intermediate-acid magmas into the carbonate strata or early emplaced plutons. The majority of these deposits host Cu and other associated elements, such as Mo, Au, Ag, Pb, and Zn. Bounded by the Hongshan–Shudu ophiolite belt, the Indosinian Zhongdian Arc can be divided into two porphyry metallogenic belts in the east and west [33,34]. The eastern belt consists of plutons such as Pulang, Songnuo, Langdu, Qiansui, and Disuga, corresponding to the Pulang Cu deposit, the Songnuo Cu deposit, the Langdu Cu deposit, etc. The western belt consists of plutons such as Chundu, Xuejiping, and Lannitang, corresponding to the formations of the Xuejiping Cu deposit, the Lannitang Cu deposit, and the Chundu Cu deposit (Figure 1b; [4,8,34,35,36]).
Minerals 14 00176 g001
Figure 1. (a) Simplified geological map of the Sanjiang area (modified after [8]). (b) Distributions of magmatic rocks and associated mineral deposits in the Zhongdian Arc (modified after [8,37]).
Figure 1. (a) Simplified geological map of the Sanjiang area (modified after [8]). (b) Distributions of magmatic rocks and associated mineral deposits in the Zhongdian Arc (modified after [8,37]).
Minerals 14 00176 g001

3. Deposit Geology

The Pulang Cu deposit, located in the northeast of the Diqing Tibetan Autonomous Prefecture, northwestern Yunnan Province, is one of the largest Cu deposits in China. At present, this deposit has been established to host Cu resources of ~5 × 106 t (with an average grade of 0.52% [37]), Mo resources of ~1.7 × 105 t (with an average grade of 0.01% [34]), and Au resources of 145 t (with an average grade of 0.18 g/t [4]), along with 1459 t of Ag and 0.4 × 106 t of Pb + Zn [19]. According to the distribution of ore bodies, the deposit can be further divided into the South, East, and North Ore Sections (Figure 2). Three sets of stratigraphic units are exposed in the ore district: the Niru Formation, the Qugasi Formation, and the Tumugou Formation (Figure 2). The Middle Triassic Niru Formation is a set of carbonate strata composed of argillaceous limestone and dolomitic limestone. The Late Triassic Qugasi Formation is mainly composed of limestone, metasandstone, and slate. The Late Triassic Tumugou Formation consists of slate, metasandstone, and volcaniclastic rock, which overlies the Niru Formation in fault contact [7].
Pulang Cu ore bodies mainly occur in the Pulang complex massif, which is composed of three Indosinian intermediate-acid lithologic units, including quartz diorite porphyry, quartz monzonite porphyry, and granodiorite porphyry. Local diorite porphyry dikes have been found in the district (Figure 2; [10]). The identified quartz monzonite porphyry and quartz diorite porphyry, with zircon U–Pb ages of 215.0 ± 1.3 Ma and 216.5 ± 1.5 Ma, respectively, have the same emplacement center. Granodiorite diorite dikes intruded into the above two types of rocks, with an emplacement age of 206.3 ± 1.0 Ma (Figure 2; [8,38]). Previous studies have indicated that the spatial distributions of the major ore bodies in Pulang are strictly controlled by the quartz monzonite porphyry (Figure 2). In addition, the age of the quartz monzonite porphyry is consistent with the Re–Os age of molybdenite in the ore bodies (216.54 ± 0.87~216.13 ± 0.86 Ma; [8]), indicating that the quartz monzonite porphyry is a mineralization source in the area.
The tectonic line in the ore district spreads along the NNW direction, which is interpreted as a compressive tectonic zone formed during the subduction of the Ganzi–Litang Ocean. Faults and secondary folds were developed in the district. For example, the Pulang anticline, as a secondary fold of the Pulang syncline, is generally dome-like and is intruded by the Pulang porphyry complex in the core. Two major thrust faults occurred in the district, including the NW-trending Heishuitang Fault and the NE-trending Quanganlida Fault. The Heishuitang Fault controlled the distribution of porphyries and ore bodies and formed secondary joints and fissures in the magmatic and surrounding sedimentary rocks, which are good ore-conducting and ore-hosting structures [39].
The K-silicate, propylitic, sericite, and argillization alterations greatly affected the rocks in the ore district. The K-silicate alteration is the product of early-stage mineralization and can be subdivided into relatively early K-feldspar alteration and relatively late biotite alteration. Among them, the K-feldspar alteration mainly occurs in the quartz monzonite porphyry in the northern and southern parts of the district. The biotite alteration is distributed mainly in the quartz monzonite porphyry and locally in the quartz diorite porphyry. Previous studies have shown that the spatial distribution of Cu mineralization is consistent with the K-silicate alteration zone [4,33]. The propylitic alteration is mainly observed in the South and North Ore Sections and is spatially distributed on the periphery of the K-silicate alteration zone and strongly superimposed on it [6]. Cao et al. [8] suggested that propylitic minerals, such as chlorite and epidote, are also closely related to Cu mineralization. In the northern part of the ore district, the propylitic alteration is closely associated with vein-like Pb–Zn mineralization. The sericitization, generally occurring in the shallow part of the mining district, is mainly developed on the eastern and western sides of the quartz monzonite porphyry. This type of alteration is superimposed on the early K-silicate and propylitic alteration zones and is associated with molybdenite mineralization. The argillization alteration zone is mainly distributed in the shallow part of the central ore district and is demonstrably controlled by structures [40].
Cu mineralization in the South and North Ore Sections is mainly developed in the central quartz monzonite porphyry and the surrounding quartz diorite porphyry, with the ore grade gradually decreasing from the center to the outside, while Cu mineralization in the East Ore Section is all located in the quartz diorite porphyry. More than 96% [41] of chalcopyrite veins occur within the quartz monzonite porphyry of South Ore Section, with elevations between 3868 and 4320 m. These veins are irregular, curving, and straight, and have general thickness between 0.2~6 cm, constituting NNW-trending “gourd-shaped” ore bodies. The North and East Ore Sections mainly host a series of E–W-trending vein-like ore bodies (Figure 2). Mineralization mainly occurs at the top part of porphyries, with the ore grade decreasing with increasing depth. The mineralization types are mainly observed as vein-like or veinlet-like ores, with minor disseminated ores. Chalcopyrite is the only Cu-bearing mineral in the deposit and is generally associated with propylitic minerals, such as chlorite and epidote in hydrothermal veins. Only a few Cu-bearing veins are observed to be associated with K-feldspar and sericite. Molybdenite is mainly observed in quartz veins associated with sericitization. The major ore minerals include chalcopyrite, molybdenite, pyrite, pyrrhotite, galena, and sphalerite, and the major gangue minerals include plagioclase, K-feldspar, quartz, hornblende, biotite, chlorite, sericite, epidote, and calcite.

4. Pb–Zn Mineralization in the North Ore Section

The Pb–Zn ore bodies in Pulang are located in the northeast of the North Ore Section and are exposed at an elevation of 4300–4500 m. The Pb–Zn mineralization in this area occurs mainly in the quartz diorite porphyry, with only a few Pb–Zn veins observed in the quartz monzonite porphyry. The alteration types associated with mineralization include sericitization and propylitic alterations (Table 1). The Pb–Zn mineralization in this area is characterized by different types of ore-bearing hydrothermal veinlets, with a density of 6–10 per meter of core. On the basis of mineral assemblages and alteration types, three types of veinlets were identified in these Pb–Zn ore bodies (referred to as veins hereinafter). (a) The first type is a Qz–Po–Ccp–Sp–Gn–(Cal, Chl, Py) vein. This type of vein is characterized by the occurrence of chalcopyrite–galena–sphalerite assemblages (Figure 3a,b). The boundaries between these veins and surrounding rocks are clear, and the shapes of these veins are mostly irregular, jagged, or wavy, with a width that is generally less than 1 cm (Figure 3a).
Pyrrhotite is abundant in these veins and often accounts for more than 50% of the volume (Figure 3a,b). Chalcopyrite and galena occur within sphalerite in disseminated grains, or in the quartz independently as medium and fine particles. Local calcite, pyrite, and chlorite are observed in some veins, and sphalerite and pyrrhotite can also be seen as disseminated clusters in the quartz diorite porphyry under the microscope (Figure 3g). This type of veins is accompanied by alteration minerals such as chlorite and epidote, with local chlorite alteration halos (Figure 3a,b; Table 1). (b) The second type is a Qz–Po–Sp–Gn–(Cal, Py, Ccp, Chl) vein. This type of vein is characterized by the presence of sphalerite–galena assemblages. The boundaries between these veins and surrounding rocks are clear, and most of these veins are straight or only slightly irregular (Figure 3d), with varying widths that are generally between 0.3 cm and 2 cm. Massive aggregates of sphalerite and galena occur in such quartz veins (Figure 3h) and account for more than 50% of the volume of the veins. In some veins, galena accounts for more than 40% of the volume. Sericitization halos are locally observed on both sides of these veins (Figure 3c,d; Table 1). (c) The third type is a Cal–Qz–Po–Gn–(Ccp, Sp, Py) vein. This vein type is characterized by abundant galena. The boundaries between these veins and surrounding rocks are clear, irregular, and straight, with a width that is generally less than 1 cm (Figure 3f). The content of gangue minerals in this type of vein is low, and the contents of galena and pyrrhotite can reach 80% locally (Figure 3i). Alteration minerals such as chlorite and epidote are observed on both sides of these veins (Figure 3e,f; Table 1). According to the observation results, the formation sequence of the main minerals of Pb–Zn veins is established (Figure 4).

5. Samples and Analytical Methods

A total of 25 core samples were collected from the drill hole ZKN002 in North Pulang (Figure 2), with sampling depths in the range of −25 to −503 m, covering different veins and alteration types. Eight quartz-bearing Pb–Zn vein samples were selected for petrographic observation and microthermometry of fluid inclusions. A total of 11 sulfide-bearing samples, 9 quartz-bearing samples, and 9 calcite-bearing samples were selected from different Pb–Zn veins for in situ S isotope, quartz H–O isotope, and calcite C–O isotope analyses.
The microthermometric analysis of fluid inclusions was performed in the fluid inclusion laboratory of the School of Land and Resources Engineering, Kunming University of Science and Technology (Kunming, China), using a Linkam THMSG600 cooling/heating stage. This instrument offers a temperature range of −196 to 600 °C during the freezing and heating processes. The measurements included the melting temperature of ice and the homogenization temperature of fluid inclusions. The precisions of temperature measurements were ±0.1 °C and ±2 °C during freezing and heating, respectively. A heating rate lower than 2 °C/s was adopted when approaching the homogenization temperature, and a heating rate of 0.1 °C/s was used near the ice melting temperature. The salinities of the fluid inclusions were calculated based on the corresponding ice-melting temperatures using the method of Bodnar et al. [42].
The analyses of in situ S isotopes, quartz H–O isotopes, and calcite C–O isotopes were conducted by Beijing Createch Testing Technology Co., Ltd. (Beijing, China). LA–MC–ICP–MS in situ S isotope analyses of pyrrhotite, pyrite, chalcopyrite, and sphalerite were performed using a Neptune Plus Multi-receiver Plasma Mass Spectrometer equipped with a 193 nm solid-state laser. Sulfide was ablated by the laser ablation system. The ablation method adopted was spot ablation, the ablation diameter was 20~30 μm, the energy density was 3 J/cm2, and the frequency was 5 Hz. Using high-purity He as the carrier gas, the aerosols produced by ablation were blown out and sent to the MC-ICP-MS for mass spectrometry determination. The standard–sample–standard intersection method was used for mass discrimination correction. The results were reported as δ34S relative to the Vienna Canyon Diablo Troilite (V-CDT), with an analytical precision better than ±0.2‰ (2σ).
The quartz separates used for H isotope analyses were handpicked under a binocular microscope to achieve a >99% purity, and then crushed to a 40–60 mesh size. The H isotopic compositions of the fluid trapped in the quartz were determined using a MAT-253 Mass Spectrometer. A total of 20 mg of quartz separates was preheated about 12 h at 90 °C to eliminate adsorbed air moisture on the surface. The oven-dried samples were then wrapped in tinfoil and placed in a furnace with glassy carbon (Flash EA, Thermo, Waltham, MA, USA) to release H2O from the inclusions at 1380 °C. After the water was released by cracking, it reacted with glassy carbon to form H2 and CO, which was carried by high purity helium (5N) and transported into the mass spectrometer (253 plus, Thermo) through the chromatographic column to determine the δD values of H2. For O isotope analysis, quartz samples were selected and ground to a 200-mesh size. The samples reacted with BrF5 in vacuum at 580 °C to extract oxygen, which was used to determine the O isotope compositions. The test accuracy of H was better than 1‰, and the test accuracy of O was better than ±0.2‰. The results were related to the V-SMOW (Vienna Standard Mean Ocean Water) [43]. The isotopic compositions of the fluid were calculated using the fractional equilibrium formula (δ18OQz-δ18Owater = 3.38 × 106/T2 − 3.40) proposed by [44] and the average homogenization temperature of FIs from the corresponding samples.
For the C-O isotope determination, a 200-mesh calcite sample of 100 μg was prepared. The samples were added into a 12 mL reaction flask. The maximum number of samples measured each time was 88, of which 18 were standard samples (GBW04405 and GBW04416). High-purity helium was used for the 600 s evacuation treatment. After emptying, 5 drops of 100% phosphoric acid were added, and the sample was placed on a 72 °C heating plate for reaction and balance. The sample was reacted with phosphoric acid, and, after reaching equilibrium, CO2 gas was passed through a 70 °C fused silica capillary column, separated from other impurity gases, and then entered the stable gas isotope mass spectrometer for determination. The δ18O and δ13C determination accuracies were lower than 0.1‰. The C-O isotopic data were reported as per mil relative to the Peedee Belemnite (PDB) standard. Using the conversion formulae of the oxygen isotope standard, SMOW, and PDB [45], the value of calcite δ18OCal relative to SMOW was obtained. The fractionation equation (δ18OCal − δ18Owater = 2.78 × 106/T2 − 3.39) between CaCO3 and H2O was obtained from O’Neil et al. [46], where T is the temperature in Kelvin.

6. Results

6.1. Petrography and Microthermometry of Fluid Inclusions

The microscopic observations reveal that the fluid inclusions in the quartz from the three different types of Pb–Zn hydrothermal veins have consistent petrographic features. Under the microscope, it is found that the fluid inclusions in minerals are mostly primary inclusions, and secondary fluid inclusions are only observed occasionally and have small sizes. This paper only discusses the primary fluid inclusions. All inclusions display liquid-rich two-phase (vapor and liquid) composition at room temperature (Figure 5), with bubbles accounting for 8 vol.% to 15 vol.%. The shapes of these primary inclusions are mostly regular or locally irregular, and they are generally distributed as inclusion clusters in quartz grains (Figure 5). The sizes of these inclusions are mostly within 5–15 μm and occasionally up to 20 μm (Figure 5).
The microthermometric results of the fluid inclusions in the quartz from the three types of Pb–Zn veins are shown in Table 2. During heating, all fluid inclusions homogenized to the liquid phase. The homogenization temperatures and salinity distribution of the fluid inclusions in different types of veins are consistent (Figure 6a,b). The homogenization temperatures of the fluid inclusions in type (a) veins range from 184 °C to 208 °C, with the ice-melting temperatures between −8.5 °C and −14.0 °C, corresponding to salinities of 12.3 wt.%–17.8 wt.% NaCl eq. The fluid inclusions in type (b) veins have homogenization temperatures in the range of 203 °C to 235 °C and ice-melting temperatures in the range of −6.9 °C to −13.2 °C, reflecting salinities between 10.4 wt.% and 17.1 wt.% NaCl eq. The fluid inclusions in type (c) veins homogenized to liquid between 194 °C and 220 °C. Their ice-melting temperatures range from −7.5 °C to −13.5 °C, corresponding to salinities of 11.1 wt.%–17.1 wt.% NaCl eq. Based on the density and isochoric formulae for NaCl-H2O systems [47], a fluid density of 0.9 to 1.0 g/cm3 (average 1.0 g/cm3) was calculated (Figure 6c). No fluid boiling assemblages occurred, and thus the minimum trapping pressures of fluid inclusions can be estimated. Based on the trapping pressures and isochoric formulae for the NaCl-H2O system [47], the entrapment pressure was estimated to range from 8 to 28 bars (average 16 bars) (Figure 6d).

6.2. S Isotopic Composition

The S isotopic compositions of chalcopyrite, pyrite, sphalerite, and pyrrhotite from the three types of Pb–Zn veins are shown in Table 3 and Figure 7. The δ34S values of pyrrhotite range from 2.3‰ to 4.5‰ (V-CDT), with an average value of 3.2‰ (V-CDT). The δ34S values of chalcopyrite range from 1.3‰ to 3.9‰ (V-CDT), with an average of 2.7‰ (V-CDT). Pyrite has δ34S values in the range of 2.5‰–4.1‰ (V-CDT), with an average value of 3.5‰ (V-CDT). The δ34S values of sphalerite are in the range of 1.6‰–3.8‰ (V-CDT), with the average being 2.6‰ (V-CDT). In type (a) veins, the average δ34S (V-CDT) of pyrrhotite, pyrite, chalcopyrite, and sphalerite are 3.1‰, 3.7‰, 3.0‰, and 2.4‰, respectively. In type (b) veins, the average δ34S (V-CDT) of pyrrhotite, pyrite, chalcopyrite, and sphalerite are 3.2‰, 3.7‰, 2.8‰, and 2.8‰, respectively. The average δ34S (V-CDT) of pyrrhotite, pyrite, chalcopyrite, and sphalerite in the type (c) veins are 3.2‰, 3.1‰, 2.4‰, and 2.4‰, respectively.

6.3. H–O Isotopic Composition of Quartz

The H–O isotope analytical results of quartz in different types of Pb–Zn veins are shown in Table 4. The δ18Owater values, calculated from the δ18OQz values and the homogenization temperatures of fluid inclusions, are between 2.4‰ and 4.3‰ (V-SMOW), with an average of 3.4‰ (V-SMOW), and the δ18Dwater values range from −120.0‰ to −46.9‰ (V-SMOW), with an average of −98.5‰ (V-SMOW).

6.4. C–O Isotopic Composition of Calcite

The C–O isotopic compositions of calcite are shown in Table 5. The δ13CCal values of calcite are between −7.9‰ and −2.3‰ (V-PDB), with an average of −5.7‰ (V-PDB). The δ18OCal values of calcite are between 11.9‰ and 13.8‰ (V-SMOW), with an average of 13.0‰ (V-SMOW).

7. Discussion

7.1. Property, Origin, and Evolution of Pb–Zn Mineralization Fluids

The petrographic characteristics of fluid inclusions indicate that, compared with the complicated fluid inclusion clusters in the major Cu ore bodies in South Pulang, the fluid inclusions in the northern Pb–Zn ore bodies are of a single type (liquid-rich inclusions with consistent bubble proportions of ~10 vol.%), indicating that Pb–Zn mineralization in North Pulang originated from a single-phase fluid without phase separation. The microthermometric results show that the homogenization temperatures and salinities of the fluid inclusions range from 184 °C to 235 °C and 10.4 wt.% to 17.8 wt.% NaCl eq., respectively, and the pressure and density of fluids range from 8 to 28 bars and 0.9 to 1.0 g/cm3 (Figure 6), respectively, implying that the fluids giving rise to Pb–Zn mineralization are characterized by a low temperature and moderate-to-low salinity.
According to the δ18Owater–δDwater correlation diagram, the Pb–Zn ore-forming fluids likely have similar H–O isotopic compositions to those of Cu–Au magmatic water and primary magmatic water, with a slight deviation to the side of the meteoric water line, implying that the mineralization fluids possibly originated from magma, with different degrees of meteoric water involvement (Figure 8).
Through a comparison with data reported in previous research, it was found that although the fluid inclusions in the Pb–Zn ore bodies of North Pulang have relatively lower homogenization temperatures, the type of these inclusions (liquid-rich inclusions) is highly consistent with those in the quartz–K-feldspar veins, quartz–epidote veins and chalcopyrite-bearing veins from South Pulang [39]. In addition, all inclusions exhibit generally similar salinities between 10 wt.% and 20 wt.% NaCl eq., implying a possible genetic relationship between northern Pb–Zn mineralization fluids and southern Cu mineralization fluids. Although the H isotopes of quartz in the Pb–Zn ore bodies exhibit large variations in the δDwater–δ18Owater diagram (Figure 8), its low values are basically consistent with previously reported data on the major ore bodies in the South Ore Section. In addition, the S isotopic composition of sulfides in the Pb–Zn ore bodies is also generally consistent with those of the South and East Ore Section. The above evidence indicates that the fluids forming Pb–Zn mineralization in North Pulang were most likely generated by the northward migration of magmatic-hydrothermal fluids from the South Ore Section. All these fluids initially originated from the southern quartz monzonite porphyry. The δDwater values exhibit a large variation range, and high values are close to the range of primary magmatic water, implying a continuous interaction between these fluids and surrounding ore-free rocks during the fluid migration process. An observation of a large number of core samples reveals that pyrrhotites in the North and East Ore Sections are much more common compared to those in the South Ore Section. In addition, the electron probe analyses show that most of these pyrrhotites are monoclinic pyrrhotite formed in medium-to-low-temperature environments [49]. It is, thus, also proposed that the fluids reacted with the reductive strata (such as the carbonaceous slate of the Tumugou Formation) during the outward migration process, which resulted in a decrease in fluid oxygen fugacity and temperature and the gradual precipitation of pyrrhotite.
Minerals 14 00176 g008
Figure 8. δDwater–δ18Owater illustration for Pb–Zn mineralization fluids in North Pulang (modified from [50,51,52,53]).
Figure 8. δDwater–δ18Owater illustration for Pb–Zn mineralization fluids in North Pulang (modified from [50,51,52,53]).
Minerals 14 00176 g008

7.2. The Source of Ore-Forming Materials

Previous studies have traced the origins of C and O in ore-forming fluids according to the fractionation characteristics of C–O isotopes produced in different chemical environments [54,55,56]. According to unpublished Raman spectral analyses on fluid inclusions, carbon dioxide is the main carbon-bearing species, and there are no reduced species (such as CH4) found in the ore forming fluids. We thus suggest that δ13CCal ≈ δ13CCO2 ≈ δ13C∑C [54]. There are three main carbon reserves: (1) marine limestones, which have average δ13C values ranging from −4‰ to 4‰ [57,58]; (2) deep-seated carbon, which has an average δ13C value of about −5‰ to −7‰ as indicated by analyses of carbonatites [59]; and (3) reduced or organic carbon in sediments, which normally has an δ13C value of less than −15‰ [60]. In this study, the carbon isotopes (δ13CCal = −2.3‰ to −7.9‰ V-PDB, mean value of −5.7‰ V-PDB) indicate that the carbon source of these mineralization fluids was likely from deep-seated carbon (magma-related) rather than originating from carbon in sediments (Figure 9a).
The δ18O values of fluids forming calcite were calculated based on the homogenization temperatures of fluid inclusions in quartz coexisting with calcite (Table 5). The calculated δ18Owater values of calcite are in a uniform range from 3.3‰ to 5.3‰ V-SMOW (similar to those of quartz calculated above, ranging from 2.4‰ to 4.3‰ V-SMOW), with an average of 4.4‰ (V-SMOW), which fall between the values of magmatic water and meteoric water but are closer to the former (Figure 9b), suggesting that the oxygen in these mineralization fluids was likely derived from magmatic-hydrothermal water, with a minor mixing of meteoric water.
Previous and our studies showed the absence of sulfate and the development of pyrrhotite in ore bodies, suggesting that the ore-forming fluids associated with Pb–Zn mineralization were reduced and that S2− was the main sulfur species [51,60,63]. Thus, the δ34S values of sulfides can approximately represent the δ34S value of bulk fluid. Meanwhile, the variation range of δ34Ssulfides in sulfides from the Pb–Zn ore bodies is small (1.3‰ to 4.5‰ V-CDT), which is consistent with the range of δ34S values of andesites, granites, and most porphyry deposits in the world (−5‰ to 5‰, [64]), indicating that the sulfur was magmatic-sourced (Figure 10). Under equilibrium conditions, the enrichment of δ34S of sulfides is in the order of pyrite > pyrrhotite > sphalerite > chalcopyrite [54]. The δ34S values of sulfide minerals in this study show the following trends: δ34SPy > δ34SPo > δ34SCcp > δ34SSp, suggesting the unequilibrium fractionation of sulfur isotopes among the sulfide minerals. This relationship reveals the possible involvement of other components (from the stratum) during the migration process of fluid, which causes an imbalance in the thermodynamic conditions of the metallogenic environment. However, the sulfur isotope composition of different sulfides in type (b) veins shows equilibrium conditions. The temperature calculated from the pyrite–sphalerite–sulfur isotope geotherms in this type of vein is applied to the ZnS-H2S fractionation equation [54], and the finally calculated δ34SH2S values range from 1.8‰ to 3.6‰ (average 2.6‰, V-CDT), which is consistent with the traditional magmatic range. Based on this, S in Pb–Zn ore bodies likely originated from the exsolution fluid of porphyry bodies, or fluids that leached sulfur from magmatic rocks or from earlier sulfide mineralization.

7.3. Genesis of Pb–Zn Mineralization

The factors leading to the precipitation of ores in hydrothermal deposits mainly include fluid cooling [65], fluid phase separation [66], fluid mixing, and fluid–rock interactions [65,67,68]. In this study, the fluid inclusions in different Pb–Zn veins from North Pulang are all of the liquid-rich two-phase type, and no boiling fluid inclusion groups were observed, indicating that phase separation was not responsible for the precipitation of Pb and Zn. As mentioned above, the wide variation range of δDwater values (Figure 8), the relatively lighter δ34S values (Figure 10), and the spatial distribution of pyrrhotite indicate possible fluid–rock interaction during fluid migration. However, there is no correlation between the δDwater values and the grades of Pb–Zn ores, implying that fluid–rock interaction was also not the major factor causing the precipitation of sphalerite and galena. The H–O isotopes likely display a mixture of magmatic fluid and meteoric water (Figure 8). In addition, the fluid inclusions in the Pb–Zn ore bodies have lower homogenization temperatures and slightly lower salinities than those of the major Cu ore bodies in the south, indicating that the addition of meteoric water accompanied by fluid cooling during the fluid migration process was possibly the key factor resulting in the precipitation of zinc–lead ore (Figure 6c,d).
At the end of the Late Triassic period, the westward subduction of the Ganzi–Litang Ocean led to the emplacement of magma originating from the upper mantle or lower crust along the NW-trending regional deep fault. The exsolution of hydrothermal fluids from the quartz monzonite porphyry formed major Cu mineralization in South Pulang. On the other hand, there was the development of a series of secondary NW- and ENE-trending joints and fissures in the plutons and on the sides of the NE-trending main faults [19]. It is hypothesized that metal-bearing hydrothermal fluids migrated northwards along the ENE-trending structural fissures, interacted with surrounding rocks along the migration path, and finally reached the northern part of the Pulang ore district. Affected by the meteoric water involvement and the cooling of fluids, sphalerite and galena eventually precipitated in fractures, generating the hydrothermal vein-type Pb–Zn mineralization in the North Ore Section of the Pulang deposit.

8. Conclusions

Three different types of ore-bearing hydrothermal veins were identified in the Pb–Zn ore bodies of North Pulang. The fluid inclusion and H–O isotope study indicates that the fluid generating the Pb–Zn mineralization was a single-phase magmatic-hydrothermal fluid characterized by low temperatures (184 °C–235 °C) and medium-to-low salinities (10.4 wt.‰–17.8 wt.‰ NaCl eq.), with a minor involvement of meteoric water.
The calcite C–O isotopes in the Pb–Zn ore bodies indicate that C likely originated from the magmatic-hydrothermal fluid, whereas the δ34S values of sulfides indicate that the S forming Pb–Zn mineralization maybe had a magmatic source, with a minor involvement of reduced S from surrounding rocks.
On the basis of the results regarding fluid inclusions, stable isotopes, and deposit geology, the fluids generating Pb–Zn mineralization in North Pulang most likely resulted from the northward migration of magmatic hydrothermal fluids that originated from South Pulang along the NEE-trending structural fissures. A strong fluid–rock interaction is suggested to have occurred during the fluid migration process. However, the involvement of meteoric water and accompanied fluid cooling were most likely the major factors leading to the eventual precipitation of sphalerite and galena.

Author Contributions

Conceptualization, X.Z. and M.D.; investigation, J.X., X.Z., M.D. and Y.S.; experimental analyses, J.X. and X.Z.; project administration, X.Z.; writing—original draft, J.X.; writing—review and editing, J.X., X.Z., M.D. and W.L. All authors have read and agreed to the published version of the manuscript.

Funding

This research was financially supported by the National Natural Science Foundation of China (Grant No. 42103062), the Yunnan Fundamental Research Project (Grant No. 202201AU070141), and the Yunnan Major Scientific and Technological Project (Grant No. 202202AG050006).

Data Availability Statement

All data are contained within the article.

Acknowledgments

We are grateful to Yunnan Diqing Non-ferrous Metals Co., Ltd., for its help during the field work. We also appreciate the Beijing Createch Testing Technology Co., Ltd., for its help during the isotope analyses. In addition, the authors thank the reviewers for their help in revising and improving the article.

Conflicts of Interest

Yan Su is an employees of Yunnan Diqing Non-Ferrous Metals Co., Ltd. The paper reflects the views of the authors and not the company.

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Figure 2. Geological sketch of the mining district of the Pulang Cu polymetallic deposit (modified after [7,10]).
Figure 2. Geological sketch of the mining district of the Pulang Cu polymetallic deposit (modified after [7,10]).
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Figure 3. Hand specimens of Pb–Zn veins and microscopic features of Pb–Zn mineralization in North Pulang. (a,b) are photos of type a veins. (c,d) are photos of type b veins. (e,f) are photos of type c veins. (g–i) microscopic features of sulfide. Abbreviations: QDP = quartz diorite porphyry, Cal = calcite, Ccp = chalcopyrite, Gn = galena, Po = pyrrhotite, Py = pyrite, Qz = quartz, and Sp = sphalerite.
Figure 3. Hand specimens of Pb–Zn veins and microscopic features of Pb–Zn mineralization in North Pulang. (a,b) are photos of type a veins. (c,d) are photos of type b veins. (e,f) are photos of type c veins. (g–i) microscopic features of sulfide. Abbreviations: QDP = quartz diorite porphyry, Cal = calcite, Ccp = chalcopyrite, Gn = galena, Po = pyrrhotite, Py = pyrite, Qz = quartz, and Sp = sphalerite.
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Figure 4. Diagram of the formation sequence of the main minerals of Pb–Zn veins from North Pulang.
Figure 4. Diagram of the formation sequence of the main minerals of Pb–Zn veins from North Pulang.
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Figure 5. Microscopic appearance of fluid inclusions in the quartz of Pb–Zn veins from North Pulang. (a,b) are photos of fluid inclusions in the type a veins. (c) is photo of fluid inclusions in the type b veins. (d–f) are photos of fluid inclusions in the type c veins. Abbreviations: V = vapor and L = liquid.
Figure 5. Microscopic appearance of fluid inclusions in the quartz of Pb–Zn veins from North Pulang. (a,b) are photos of fluid inclusions in the type a veins. (c) is photo of fluid inclusions in the type b veins. (d–f) are photos of fluid inclusions in the type c veins. Abbreviations: V = vapor and L = liquid.
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Figure 6. Histograms of homogenization temperatures (a) and salinities (b) of fluid inclusions in the quartz of Pb–Zn veins from North Pulang. (c,d) Scatter plot of homogenization temperatures and salinities of Cu- and Pb–Zn-related fluid inclusions in quartz from South and North Pulang. Isobars are calculated from the equations of [48]; the data for South Pulang are according to [39].
Figure 6. Histograms of homogenization temperatures (a) and salinities (b) of fluid inclusions in the quartz of Pb–Zn veins from North Pulang. (c,d) Scatter plot of homogenization temperatures and salinities of Cu- and Pb–Zn-related fluid inclusions in quartz from South and North Pulang. Isobars are calculated from the equations of [48]; the data for South Pulang are according to [39].
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Figure 7. (a) δ34S value frequency histogram of sulfides in Pb–Zn veins from North Pulang (the data of South Pulang are according to [34], and the data of East Pulang are according to [34,36]). (b) Histogram of δ34S values’ frequency distribution for type (a) vein sulfide. (c) Histogram of δ34S values’ frequency distribution for type (b) vein sulfide. (d) Histogram of δ34S values’ frequency distribution for type (c) vein sulfide.
Figure 7. (a) δ34S value frequency histogram of sulfides in Pb–Zn veins from North Pulang (the data of South Pulang are according to [34], and the data of East Pulang are according to [34,36]). (b) Histogram of δ34S values’ frequency distribution for type (a) vein sulfide. (c) Histogram of δ34S values’ frequency distribution for type (b) vein sulfide. (d) Histogram of δ34S values’ frequency distribution for type (c) vein sulfide.
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Figure 9. (a) δ13CCal–δ18Owater illustration of calcite from the Pb–Zn ore bodies in North Pulang (modified after [61]). (b) Calculated oxygen isotopic composition of waters in equilibrium from different minerals in the North Pulang deposit. The composition of Mesozoic meteoric water in the Sanjiang region was obtained from [62], and the composition of primary magmatic water was obtained from [52].
Figure 9. (a) δ13CCal–δ18Owater illustration of calcite from the Pb–Zn ore bodies in North Pulang (modified after [61]). (b) Calculated oxygen isotopic composition of waters in equilibrium from different minerals in the North Pulang deposit. The composition of Mesozoic meteoric water in the Sanjiang region was obtained from [62], and the composition of primary magmatic water was obtained from [52].
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Figure 10. (a) The δ34S value ranges of representative sulfur reservoirs in nature [37]. (b) The δ34S value ranges of different sulfides from North, South, and East Pulang (the data of the East and North Ore Section are according to [34,50]).
Figure 10. (a) The δ34S value ranges of representative sulfur reservoirs in nature [37]. (b) The δ34S value ranges of different sulfides from North, South, and East Pulang (the data of the East and North Ore Section are according to [34,50]).
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Table 1. Characteristics of Pb–Zn-bearing veins in the Pulang deposit.
Table 1. Characteristics of Pb–Zn-bearing veins in the Pulang deposit.
Vein Typeabc
Mineral assemblageQz–Po–Ccp–Sp–Gn–(Cal, Chl, Py)Qz–Po–Sp–Gn–(Cal, Py, Ccp, Chl)Cal–Qz–Po–Gn–(Ccp, Sp, Py)
AlterationEp, ChlSerEp, Chl
Vein width0.3~1 cm0.2~2 cm0.2~2 cm
Structural characteristicJagged—wavyUneven thickness, straight—wavyStraight—curved
Depth60.5 m, 503 m305~376 m25 m, 302 m
Abbreviations: Cal = calcite, Ccp = chalcopyrite, Chl = chlorite, Ep = epidote, Gn = galena, Po = pyrrhotite, Py = pyrite, Qz = quartz, Sp = sphalerite, and Ser = sericite.
Table 2. Microthermometric data for fluid inclusions in the quartz of ore-bearing veins from the Pb–Zn ore bodies in North Pulang.
Table 2. Microthermometric data for fluid inclusions in the quartz of ore-bearing veins from the Pb–Zn ore bodies in North Pulang.
Vein TypeSample No.Host MineralFluid Inclusion TypeGenetic TypeNumber of AnalysesTm, ice 1 (°C)Th, TOT 2 (°C)Salinity (wt.% NaCl eq.)
aN002-06-1QuartzLVPrimary15−8.9~−13.9184~19712.7~17.7
N002-06-2QuartzLVPrimary10−8.5~−12.6187~19912.3~16.2
N002-06-3QuartzLVPrimary8−9.9~−14.0189~20813.8~17.8
bN002-18-1QuartzLVPrimary5−7.9~−13.2203~21211.6~17.1
N002-18-2QuartzLVPrimary6−6.9~−11.5226~23510.4~15.5
N002-18-3QuartzLVPrimary8−7.3~−10.9210~23310.9~14.9
cN002-15-1QuartzLVPrimary5−8.6~−13.5194~20912.4~17.1
N002-15-2QuartzLVPrimary8−7.5~−11.2211~22011.1~15.2
1 Tm, ice = ice-melting temperature; 2 Th, TOT = homogenization temperature; and LV = liquid-rich two-phase FIs.
Table 3. S isotopic compositions of sulfides in ore veins in Pb–Zn ore bodies from North Pulang.
Table 3. S isotopic compositions of sulfides in ore veins in Pb–Zn ore bodies from North Pulang.
Vein TypeSample No.Sulfideδ34S (‰ V-CDT)Vein TypeSample No.Sulfideδ34S (‰ V-CDT)
aN002-04-1Pyrrhotite3.4 N002-18-2-1Pyrite3.4
N002-04-2Pyrrhotite2.3N002-18-2-2Pyrite3.9
N002-04-3Pyrrhotite3.2N002-16-2-1Chalcopyrite2.2
N002-06-2Pyrrhotite3.5N002-18-2-2Chalcopyrite3.4
N002-06-2-1Pyrite4.1N002-13-1Sphalerite2.5
N002-06-3-1Pyrite3.2N002-13-2Sphalerite2.2
N002-04-1Chalcopyrite1.7N002-16-2-3Sphalerite2.3
N002-06-2-1Chalcopyrite3.0N002-17-1Sphalerite2.6
N002-06-2-2Chalcopyrite3.4N002-17-2Sphalerite3.1
N002-06-2-3Chalcopyrite3.9N002-18-2-1-1Sphalerite2.0
N002-06-3-1Chalcopyrite2.8N002-18-2-1-2Sphalerite3.8
N002-04-1-1Sphalerite2.1N002-18-2-2-1Sphalerite3.3
N002-04-1-2Sphalerite1.9N002-18-2-2-2Sphalerite3.7
N002-04-2Sphalerite2.1cN002-01-1Pyrrhotite3.6
N002-04-3Sphalerite2.1N002-01-2Pyrrhotite3.0
N002-06-2-1Sphalerite3.4N002-15-1Pyrrhotite3.0
N002-06-2-2Sphalerite3.1N002-12-1Pyrite2.5
N002-06-2-3Sphalerite2.2N002-12-2Pyrite3.7
bN002-13-2Pyrrhotite2.5N002-01-1Chalcopyrite2.9
N002-16-2-1Pyrrhotite2.9N002-01-2Chalcopyrite2.7
N002-16-2-2Pyrrhotite3.0N002-12-1-1Chalcopyrite1.3
N002-16-2-3Pyrrhotite2.5N002-12-2-1Chalcopyrite2.5
N002-17-1Pyrrhotite3.3N002-01-1Sphalerite3.2
N002-17-2Pyrrhotite3.1N002-01-2Sphalerite3.2
N002-18-2-1Pyrrhotite3.5N002-12-1-1Sphalerite1.7
N002-18-2-2Pyrrhotite4.5N002-12-1-2Sphalerite1.6
Table 4. H–O isotopic compositions of quartz in ore-bearing veins in Pb–Zn ore bodies from North Pulang.
Table 4. H–O isotopic compositions of quartz in ore-bearing veins in Pb–Zn ore bodies from North Pulang.
Vein TypeSample No.Mineralδ18OQz
(‰ V-SMOW)		δDwater
(‰ V-SMOW)		Th (°C)δ18Owater 1
(‰ V-SMOW)
a N002-06Quartz14.5−46.91942.4
b N002-16Quartz14.8−114.52204.3
N002-17Quartz14.8−111.92204.3
N002-18Quartz13.8−113.32203.3
cN002-01Quartz14.4−72.22093.3
N002-05Quartz14.4−85.22093.3
N002-09Quartz14.4−108.62093.2
N002-11Quartz14.7−113.62093.6
N002-15Quartz14.4−120.02093.3
1 δ18Owater is calculated from δ18OQz, using given Th temperatures of quartz-hosted fluid inclusions.
Table 5. C–O isotopic compositions of calcite in ore-bearing veins in Pb–Zn ore bodies from the North Pulang deposit.
Table 5. C–O isotopic compositions of calcite in ore-bearing veins in Pb–Zn ore bodies from the North Pulang deposit.
Vein TypeSample No.Mineralδ13CCal (‰ V-PDB)δ18OCal (‰ SMOW)Th (°C)δ18Owater 1
(‰ SMOW)
aN002-06Calcite−2.313.61944.2
N002-08Calcite−5.213.31944.0
bN002-16Calcite−7.912.82204.7
N002-17Calcite−7.213.22205.1
N002-18Calcite−6.912.82204.8
cN002-01Calcite−6.613.82095.3
N002-05Calcite−6.212.92094.3
N002-09Calcite−5.112.82094.3
N002-11Calcite−4.211.92093.3
1 δ18Owater is calculated from δ18OCal using given Th temperatures of fluid inclusions in associated quartz.
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Xu, J.; Zhao, X.; Deng, M.; Li, W.; Su, Y. Genesis of Pb–Zn Mineralization in the Pulang Cu Polymetallic Deposit in Yunnan Province, China: Insights from Analyses of Geology, Fluid Inclusions and C–H–O–S Isotopes. Minerals 2024, 14, 176. https://doi.org/10.3390/min14020176

AMA Style

Xu J, Zhao X, Deng M, Li W, Su Y. Genesis of Pb–Zn Mineralization in the Pulang Cu Polymetallic Deposit in Yunnan Province, China: Insights from Analyses of Geology, Fluid Inclusions and C–H–O–S Isotopes. Minerals. 2024; 14(2):176. https://doi.org/10.3390/min14020176

Chicago/Turabian Style

Xu, Jingwei, Xiaoyu Zhao, Mingguo Deng, Wenchang Li, and Yan Su. 2024. "Genesis of Pb–Zn Mineralization in the Pulang Cu Polymetallic Deposit in Yunnan Province, China: Insights from Analyses of Geology, Fluid Inclusions and C–H–O–S Isotopes" Minerals 14, no. 2: 176. https://doi.org/10.3390/min14020176

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