Geochemical Features of Volcanic Rocks from the Shaerbuti Mountain Complex, West Junggar, Xinjiang, China: Implications for Recycling of Materials
1
Key Laboratory of Seismic and Volcanic Hazards, China Earthquake Administration, Beijing 100029, China
2
National Observation and Research Station of Jilin Changbaishan Volcano, Institute of Geology, China Earthquake Administration, Beijing 100029, China
3
Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
4
Hebei Key Laboratory of Geotechnical Engineering Safety and Deformation Control, Hebei University of Water Resources and Electric Engineering, Cangzhou 061001, China
*
Author to whom correspondence should be addressed.
Minerals 2023, 13(1), 75; https://doi.org/10.3390/min13010075
Submission received: 6 December 2022
/
Revised: 23 December 2022
/
Accepted: 31 December 2022
/
Published: 3 January 2023
(This article belongs to the Section Mineral Geochemistry and Geochronology)
Abstract
:In this paper, we focus on the geological features of volcanic edifices and the geochemistry of intermediate–basic volcanic rocks of Shaerbuti Mountain, which offer a new perspective on recycled materials in the study area. The Shaerbuti volcanic rocks consist of calc-alkali basalt and andesite formed in an arc setting. The porphyroclastic texture of basalt, explosive breccia rock, and the distribution of both breccia and agglomerate provide robust evidence that a volcanic edifice exists in Shaerbuti Mountain. Based on geochemical features, the Shaerbuti volcanic rocks have been identified as being of two types. Type I volcanic rocks have light rare earth element (LREE)-enriched patterns, with La/Sm ratios of 2.27–4.03, Th/Yb ratios of 0.50–1.46, and Nb/Yb ratios of 1.11–2.28. Type II volcanic rocks display a flat rare earth element (REE) pattern, with La/Sm ratios ranging from 1.83 to 2.43, Th/Yb ratios ranging from 0.24 to 0.45, and Nb/Yb ratios ranging from 0.87 to 0.93. In the studied rocks, MgO-Cr, MgO-Ni and MgO-CaO present a positive relationship, which indicates clinopyroxenes crystallized. The Sr-Nd-Pb isotopic compositions of these basalts present values of 0.7045 to 0.7063 ((87Sr/86Sr)i), 6.4 to 6.6 (εNd(t)), and 17.1300 to 18.3477 ((206Pb/204Pb)i), respectively. According to Sr-Nd-Pb isotope features, we argue that melts of altered oceanic crust and sediments were incorporated into the source. We also evaluate the water content (0.55%–6.72%) of the studied volcanic rocks.
1. Introduction
The Central Asian Orogenic Belt (CAOB) is a large orogenic belt in Asia. West Junggar, Xinjiang, China, is located in the midwestern part of the CAOB [1,2,3]. Intraoceanic subduction, oceanic crust–continent subduction, and continent–continent collision are common features in this region [4]. During the Paleozoic Era, subduction dominated the tectonic regime, such as the early Paleozoic Xiemisitai–Shaerbuti arc, Neopaleozoic Sawuer arc, and Barluke–Kelamayi arc [5]. The study area is located in the northeastern part of Shaerbuti Mountain, which crop out east of the Xiemisitai–Shaerbuti volcanic arc. The rock assemblage of ophiolites, arc volcanic rock and Nb-enriched basalt has been reported by previous researchers [2], with the conclusion of intraoceanic subduction with ridge subduction [5].
Although previous studies have identified basalts as forming the setting, the recycled materials (sediments, oceanic crust and water) that have been added to the source of volcanic rocks have not been previously discussed. The addition of water to mantle sources can change the temperatures and pressures of melting [6,7]. In addition, sediments and oceanic crust in mantle sources enhance the oxygen fugacity of the mantle [8]. Therefore, deciphering recycled materials is important to uncover the genesis of basalts.
In this paper, we aim to uncover fractional crystallization, oxygen fugacity and the detailed recycled materials that have added to the magma source. Herein, we present new major and trace element features and Sr-Nd-Pb isotopic compositions to discuss which kinds of minerals crystallized from magma, the oxygen fugacity of the source mantle and the roles of fluid and sediments in the genesis of volcanic rocks.
2. Method
More than 152 samples were collected southeast of Shaerbuti Mountain. We selected 11 samples without alteration for whole-rock chemical analyses. Additionally, five of the 11 samples were measured for Sr and Nd isotope analysis, and six of 11 were selected for Pb isotope study.
Major element concentrations and the Sr-Nd-Pb isotope ratios of volcanic rocks were measured at the Institute of Geology and Geophysics, Chinese Academy of Sciences. Trace element concentrations were measured at the Beijing Research Institute of Uranium Geology. Major elements were determined with an XRF-1500 (SHMADZU) instrument using the X-ray fluorescence spectrometry method with an accuracy of analysis of better than 0.2%. Before the analysis of major elements, a preheating method was used to measure the loss on ignition (LOI) with the temperature held at 1200 °C for four hours. Chinese reference materials (GBW07105, GBW07111 and GBW07112) were also determined during the measuring of the samples. The measured and literature values present agreed values within error. We use potassium dichromate to measure Fe2+ in basalts. Sample powders (0.5 g) were dissolved in HF and H2SO4. Residual F was eliminated by H3BO3. We then used potassium dichromate to measure the concentration of Fe2+. Fe3+ was calculated by Fe2O3T and the abundance of Fe2+.
The trace elements of the volcanic rocks were measured at the Beijing Research Institute of Uranium Geology. Trace element concentrations were determined by an Agilent 7700e inductively coupled plasma–mass spectrometer (ICP-MS) with a precision of better than 10%. The experimental procedures for trace elements are identical to those described by Li [9,10]. Reference materials (BHVO-2, BCR-2 and RGM-2) were used to monitor the analytic results.
Six samples were crushed to powder for Rb-Sr and Sm-Nd isotopic analysis, and these samples were then measured using a Neptune Plus multicollector (MC)-ICP-MS instrument. The results from the whole procedure blank were lower than 200 pg for the Sr isotopic ratios and lower than 100 pg for the Sm-Nd ratios. Analyses of the NIST 987 and GSB 04-3258-2015 standards yielded 87Sr/86Sr ratios of 0.710242 ± 14 (2SD, n = 345) and 143Nd/144Nd ratios of 0.512440 ± 6 (2SD, n = 31). The Rb-Sr and Sm-Nd isotopic analysis procedures used were similar to those described by Li [9,10].
Five samples were measured for Pb isotope analysis using a Neptune Plus multicollector (MC)-ICP-MS instrument. The international standard NIST-987 (208Pb/206Pb = 2.164940 ± 15, 207Pb/206Pb = 0.914338 ± 7, 204Pb/206Pb = 0.0591107 ± 2), with a whole procedure blank lower than 100 pg was used to monitor instrument stability during data collection and correct mass fractionation [10].
3. Geological Background and Petrography
The Shaerbuti volcanic rocks, located in the Hebukesaier County, belong to the Xiemisitai-Shaerbuti arc (east part of the West Junggar) which dominantly formed in the Paleozoic period (Figure 1). Previous studies have reported that volcanic rocks of the studied field have formed in an arc setting with the subduction of the mid-oceanic ridge by the formation of ophiolite, type I (called type IIIb by Shen et al. [5]), type II (called type IIIa by Shen et al. [5]) volcanic rocks and Nb-enriched basalt [5]. These arc type volcanic rocks mainly formed in the Ordovician period [5]. Shaerbuti Mountain is bounded by the Hongguleleng fault to the North and the Xiemisitai fault to the South. The faults in this area are distributed in Northwest, Northeast and East–West orientations.
In the Early Ordovician period, mid-ocean ridge spreading occurred, forming a mid-ocean ridge basalt (MORB)-type ophiolite [11,12]. A volcanic arc formed during the Middle Ordovician period due to subduction with Nb-enriched basalt, which has a close relationship with ridge subduction. Shen et al. [5] and Sun et al. [13] studied the volcanic rocks located southwest of Shaerbuti Mountain and concluded that they formed in an arc setting.
The volcanic rocks in this study were sampled from the northeastern part of Shaerbuti Mountain, which contains a suite of mafic to intermediate igneous rocks and volcanic pyroclastic rocks. Basalt, andesite, and the equivalence of volcanic pyroclastics, such as andesitic breccia, andesitic agglomerate, and tuff, are the primary rocks (Figure 2).
The basalt in this group has a porphyritic texture, with plagioclase and augite phenocrysts and fine-grained plagioclase and glass in the groundmass. Phenocrysts usually occupy 20%–40% of the volume and have sizes between 0.1 and 1 mm (Figure 3a–d). The andesite also has a porphyritic texture, with plagioclase and hornblende phenocrysts occupying 15%–50% of the volume. Zonal texture and resorption zones are common in plagioclase. Pyroxene also contains resorption zones. A biotite diorite porphyrite has a porphyritic texture, with plagioclase, hornblende, and biotite phenocrysts, with fine-grained quartz and plagioclase in the groundmass. Phenocrysts occupy 25%–50% of the volume, with sizes between 0.3 mm and 2 mm. Andesitic breccia comprises debris, with sizes up to 6 mm and a matrix. The crystal tuff comprises glass debris and crystal fragments composed of plagioclase in a mafic to intermediate groundmass.
4. Results
4.1. Identification of Volcanic Edifice
Based on the volcanic rock characteristics, we recognize a volcanic edifice Northeast of Shaerbuti Mountain (Figure 2). First, we discern the volcanic edifice according to the distributions and contents of breccia and agglomerate (Figure 4a,b). A large volume of agglomerate (10%) exists in the proximal area of the volcanic edifice. However, the volume of breccias (30%) is larger than that of the agglomerate (5%) in the distal area of the volcanic edifice. Second, annular faults, which usually form when a volcanic crater collapses, are robust indications of the volcanic edifice. Northeast- and South-directed and cyclic faults measured in the study area further indicate that a volcanic edifice exists in Shaerbuti Mountain (Figure 2). Third, explosive breccia is robust evidence for the volcanic edifice [14]. In the study area, we found three types of explosive breccia with compositions of andesite and gabbro (Figure 4c–f). Fourth, we also found layer of breccia and tuff near explosive breccia (Figure 4g). Therefore, we conclude that a volcanic edifice exists Northeast of Shaerbuti Mountain.
4.2. Major and Trace Element Geochemistry
The major and trace element concentrations of the Shaerbuti basalt and andesite are listed in Table 1. The loss on ignition (LOI) values from the studied volcanic rocks ranges from 2.05 to 3.96 wt.%, indicating the surface alteration of the volcanic rocks. In addition, the alteration box is also an important indicator to illustrate the degree of alteration. In the alteration box, several samples of the Shaerbuti volcanic rocks plot outside the area of the least altered box (Figure 5), which indicates that moderate alteration exists in the studied volcanic rocks. The elements Nb and Y are high field strength elements (HFSEs) that are not influenced by alteration. Therefore, we use Nb/Y ratios and SiO2 to uncover the lithology of the Shaerbuti volcanic rocks.
Based on the geochemical characteristics of major and trace elements, two types of volcanic rocks have been recognized (Table 1). They are type I volcanic rock (sample HG17-46, 15BHG45, 15HG152, HG2-11, 15BHG129, HG17-43 and HG17-2) and type II volcanic rock (sample 15HG125, 15HG74-2, 15HG127, 15HG76).
Although type I (enrichment of LREE patterns) and type II (flat rare earth element (REE) patterns) samples have similar major element concentrations, they display different trace element features. Type II volcanic rocks have lower ratios of Nb/Y (Figure 6) than type I volcanic rocks. In addition, type II volcanic rocks have higher concentrations of Th than type I volcanic rocks. The chondrite-normalized REE diagram (Figure 7a) shows that the type I volcanic rocks are enriched in LREEs, with (La/Sm)N, (La/Yb)N, and (Gd/Yb)N ratios ranging from 2.27 to 4.03, from 3.24 to 7.31, and from 1.08 to 1.67, respectively. However, type II volcanic rocks show a flat REE pattern, with (La/Sm)N, (La/Yb)N, and (Gd/Yb)N ratios from 1.84 to 2.43, from 1.84 to 2.72, and from 0.96 to 1.11, respectively (Figure 7b). In the spider diagram (Figure 8a,b), all volcanic rocks are enriched in large ion lithophile elements (LILEs). Additionally, these rocks have HFSE-depleted characteristics, such as Nb and Ta. Compared with the type II volcanic rocks, the type I volcanic rocks have higher Th/Nd values. Type I volcanic rocks also have higher Nb/Yb and Th/Yb ratios and Nb and Y contents than type II volcanic rocks.
4.3. Sr-Nd-Pb Isotopes of the Shaerbuti Volcanic Rock
The measured and initial (back-calculated to 450 Ma) Sr–Nd isotopes and Pb isotopes of the Shaerbuti Mountain volcanic rocks are listed in Table 2 and Table 3, respectively. These rocks show limited variation in their Sr-Nd-Pb isotopic ratios. However, type II volcanic rocks have higher Nd and lower Sr–Pb isotopic values than type I samples. The type I volcanic rocks have (87Sr/86Sr)i values ranging from 0.7052 to 0.7063 and εNd(t) values ranging from 6.5 to 6.6, while the type II volcanic rocks display lower Sr–Nd isotopic compositions, with (87Sr/86Sr)i values ranging from 0.7045 to 0.7046 and εNd(t) values ranging from 6.4 to 6.5. Additionally, the type I volcanic rocks have (206Pb/204Pb)i values ranging from 17.1300 to 18.3477, (207Pb/204Pb)i values ranging from 15.4595 to 15.5346 and (208Pb/204Pb)i values ranging from 37.6077 to 37.9906, while the type II volcanic rocks present lower Pb isotopic compositions, with (206Pb/204Pb)i values ranging from 17.0523 to 17.8942, (207Pb/204Pb)i values ranging from 15.4544 to 15.5278 and (208Pb/204Pb)i values ranging from 37.7004 to 37.9063.
5. Discussion
5.1. Tectonic Setting
The tectonic history of the Shaerbuti Mountain volcanic rocks has been reported by Shen et al. [5]. In the Early Ordovician period, mid-ocean ridge spreading occurred, forming a MORB-type ophiolite. During the Middle Ordovician period, a volcanic arc formed due to subduction. Nb-enriched basalt, which has a close relationship with ridge subduction, has been reported by Shen et al. [5]. Herein, we studied the volcanic rocks located 5 km south of the Hongguleleng ophiolite. The type I and II basic to intermediate volcanic rocks are composed of basalt and andesite and show middle-potassium calc-alkaline series characteristics with a high Mg#. The (La/Yb)N ratios of the type I and II basalt and andesite range from 3.28 to 7.31, with LREE enrichment. These volcanic rocks also show enriched LILEs. The HFSEs in these rocks are depleted, as with Nb and Ta, for example. Woodhead [23] previously argued that magmas sourced from the subduction zone had similar LREE, LILE, and HFSE features. The Pb isotopic compositions of the Shaerbuti volcanic rocks (206Pb/204Pb = 18.6570–19.1590, 207Pb/204Pb = 15.5530–15.6810) also display similar values to those of the mature arc (206Pb/204Pb = 18.0000–19.5000, 207Pb/204Pb = 15.5000–15.7000, [24]). Based on the rock type, trace element characteristics and lead isotopic features, we argue that these rocks formed in an island arc setting.
5.2. Impact of Fractional Crystallization
Although postmagmatic alteration exists in Paleozoic volcanic rocks with minor chlorite, most samples still have low loss on ignition values (<3%). Some samples plot in the field of least alteration (Figure 5). We use samples with a limited effect of alteration to indicate the fractional crystallization process.
The Shaerbuti Mountain volcanic rocks (type I and type II) show low and variable Mg# values (48–82, average value of 64.2) and low concentrations of Cr (5.25–255) and Ni (3.52–25.8), indicating that these igneous rocks have undergone variable degrees of fractional crystallization. The linear relationships between MgO and Cr, Ni, CaO and SiO2 are efficient indicators to illustrate the process of fractional crystallization of clinopyroxene [25,26]. In the diagrams of MgO-Cr, MgO-Ni and MgO-CaO (Figure 9a–c), these elements in the Shaerbuti volcanic rocks present positive correlation. However, the diagrams of MgO-SiO2 present negative correlation (Figure 9d). All of these correlations support fractional crystallization of clinopyroxenes. A weak negative Eu anomaly presented by the REE patterns indicates that the crystallization of plagioclase is not a significant fractional phase. There is also no obvious Fe-Ti oxide crystallization, as demonstrated by the lack of a significant relationship between MgO and TiO2.
5.3. Material Addition to the Magma Source
We believe that subduction slab melts have added to the source of type I and type II basalts. Several lines of evidence are listed below. First, the studied basalts and andesites have 87Sr/86Sr isotopes and 143Nd/144Nd isotopes on the right side of the mantle array with anomalous features, which can barely be interpreted by two end members between the depleted mantle (DM) and sediments. Therefore, we add altered oceanic crust (AOC) as the third end member (Figure 10a). The three-end member model (DM, 6 percent of sediments and AOC) erected by Pang et al. [25] displays robust correlation with the studied samples. Second, Pb isotopes show additional evidence for sediments, DM, and AOC mixing in the origin of the studied volcanic rocks, with all samples plotting in the mixture region (Figure 10b). Third, ridge subduction exists north of Shaerbuti Mountain, as indicated by Nb-rich basalts with high Zr and Nb concentrations [5]. As suggested by the Pb isotopic diagram, we also recognize the AOC composition in the source. Therefore, we conclude that subducted oceanic plate melts have added to the magma source.
K and Ba are generally used to identify the addition of fluids in a magma source because of the LILE features. However, Th and La are less affected by the fluids. Therefore, the ratios of Ba/Th and Ba/La are effective indicators with a variable range for fluid addition in the magma origin. To obtain exact values of the Shaerbuti volcanic rocks, we select data with alteration boxes where samples should plot in the area of the least altered box, and LOI values are lower than 2%. The values of Ba/Th and Ba/La range from 10 to 2532 and 2 to 504, respectively, with positive anomalies of LILEs (such as Ba and K) in the spider diagram, illustrating fluid addition to the source of the Shaerbuti volcanic rocks. Wang et al. [34] proposed an equation (H2O/Ce = 0.1092–0.0008 × (Ba/La) + 0.0001 × (Ba/La)2) to calculate the water content in arc basalt. Based on the suggested formula, we estimated the concentration of water in the study area, ranging from 0.55% to 6.72%.
When adding to the source, fluids generally carry sediment components during subduction. We argue that several percent of the sediments were added to the magma source, based on the lines of evidence listed below. Th is generally concentrated in sediments due to its weak mobility. Compared with Sm, sediments also contain high concentrations of La. Therefore, the ratios of (La/Sm)N and Th/Yb are efficient indicators of sediment addition. The studied basalts and andesites present (La/Sm)N and Th/Yb values range from 0.99 to 3.61 and 0.133 to 2.37, respectively. The Sr-Nd-Pb isotopes of the studied samples (Figure 10) also reveal sediments added to the Shaerbuti volcanic rocks with high values of radiogenic Sr-Pb.
6. Conclusions
Shaerbuti Mountain is located in the Western CAOB, and we studied its geological and geochemical features. We found a volcanic edifice in the Eastern part of this mountain, with evidence of a porphyroclast texture in basalt, cyclic and annular faults, explosive breccia rock, and the distribution of breccia and agglomerate. Based on geochemical data, two types of volcanic rocks have been separated: type I volcanic rocks have a light rare earth element (LREE)-enriched pattern, with La/Sm ratios of 2.27–4.03, Th/Yb ratios of 0.50–1.46, and Nb/Yb ratios of 1.11–2.28, while type II volcanic rocks display a flat rare earth element (REE) pattern, with La/Sm ratios ranging from 1.83 to 2.43, Th/Yb ratios ranging from 0.24 to 0.45, and Nb/Yb ratios ranging from 0.87 to 0.93. Based on the relationship between whole-rock MgO and Ni, Cr, SiO2 and CaO, we conclude that clinopyroxenes have crystallized. The isotopic compositions of these basalts present Sr isotopic values of 0.7045 to 0.7063, εNd isotopic values of 6.4 to 6.6, and 206Pb/204Pbi isotopic values of 17.1300 to 18.3477. The modeling results (Sr-Nd-Pb isotopic compositions) show that the studied volcanic rocks plot in a mixed area among sediments, oceanic crust and depleted mantle, which indicates that sediments and oceanic crust have added to the magma source. In addition, we evaluate the water contents (0.55%–6.72%) of the studied volcanic rocks.
Author Contributions
Conceptualization, J.S.; Data curation, J.S.; Formal analysis, J.S.; Methodology, J.S.; Writing—original draft, J.S.; Writing—review & editing, J.S., N.L., C.D. and Y.R. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by Ping Shen grant number (41772089) National Natural Science Foundation of China. And the APC was funded by Cheng Dong and Yanhong Ren.
Data Availability Statement
The data that supports the findings of this study are available in this paper.
Acknowledgments
This research was supported by National Natural Science Foundation of China (41772089). And we thanks Ping Shen for funding.
Conflicts of Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References
- Şengör, A.M.C.; Natal’In, B.A.; Burtman, V.S. Evolution of the Altaid tectonic collage and Palaeozoic crustal growth in Eurasia. Nature 1993, 364, 299. [Google Scholar] [CrossRef]
- Windley, B.F.; Alexeiev, D.; Xiao, W.J.; Kröner, A.; Badarch, G. Tectonic models for accretion of the Central Asian Orogenic Belt. J. Geol. Soc. 2007, 164, 31–47. [Google Scholar] [CrossRef] [Green Version]
- Shen, P.; Pan, H.D.; Shen, Y.C.; Yan, Y.H.; Zhong, S.H. Main deposit styles and associated tectonics of the West Junggar region, NW China. Geosci. Front. 2015, 6, 175–190. [Google Scholar] [CrossRef] [Green Version]
- Xiao, W.J.; Han, C.M.; Yuan, C.; Sun, M.; Lin, S.F.; Chen, H.L.; Li, Z.L.; Li, J.L.; Sun, S. Middle Cambrian to Permian subduction-related accretionary orogenesis of Northern Xinjiang, NW China: Implications for the tectonic evolution of central Asia. J. Asian Earth Sci. 2008, 32, 102–117. [Google Scholar] [CrossRef]
- Shen, P.; Pan, H.D.; Xiao, W.J.; Shen, Y.C. An Ordovician intra-oceanic subduction system influenced by ridge subduction in the West Junggar, Northwest China. Int. Geol. Rev. 2014, 56, 206–223. [Google Scholar] [CrossRef]
- Katz, R.F.; Spiegelman, M.; Langmuir, C.H. A new parameterization of hydrous mantle melting. Geochem. Geophys. Geosyst. 2003, 4, 19. [Google Scholar] [CrossRef]
- Asimow, P.D.; Langmuir, C.H. The importance of water to oceanic mantle melting regimes. Nature 2003, 421, 815–820. [Google Scholar] [CrossRef] [PubMed]
- Parkinson, I.J.; Arculus, R.J. The redox state of subduction zones: Insights from arc-peridotites. Chem. Geol. 1999, 160, 409–423. [Google Scholar] [CrossRef]
- Li, C.F.; Chu, Z.Y.; Guo, J.H.; Li, Y.L.; Yang, Y.H.; Li, X.H. A rapid single column separation scheme for high-precision Sr–Nd–Pb isotopic analysis in geological samples using thermal ionization mass spectrometry. Anal. Methods 2015, 7, 4793–4802. [Google Scholar] [CrossRef]
- Li, C.F.; Wang, X.C.; Guo, J.H.; Chu, Z.Y.; Feng, L.J. Rapid separation scheme of Sr, Nd, Pb, and Hf from a single rock digest using a tandem chromatography column prior to isotope ratio measurements by mass spectrometry. J. Anal. At. Spectrom. 2016, 31, 1150–1159. [Google Scholar] [CrossRef]
- Yang, G.; Li, Y.; Xiao, W.; Tong, L. OIB-type rocks within West Junggar ophiolitic mélanges: Evidence for the accretion of seamounts. Earth-Sci. Rev. 2015, 150, 477–496. [Google Scholar] [CrossRef]
- Yang, G.; Li, Y.; Tong, L.; Wang, Z.; Si, G. An Early Cambrian plume-induced subduction initiation event within the Junggar Ocean: Insights from ophiolitic mélanges, arc magmatism, and metamorphic rocks. Gondwana Res. 2015, 88, 45–66. [Google Scholar] [CrossRef]
- Sun, J.H.; Shen, P.; Pan, H.D.; Cao, C.; Li, C.H.; Feng, H.X.; Zheng, J.H. Geological and structure background characteristics of Hongguleleng copper deposit, Xinjiang. Miner. Depos. 2018, 37, 587–610, (In Chinese with English abstract). [Google Scholar]
- Pan, H.D.; Shen, P.; Dai, H.W.; Yan, Y.H.; Zhong, S.H. Volcanism and deposition of the Hongguleleng copper deposit, West Junggar. Miner. Deposits 2012, 31, S1. (In Chinese) [Google Scholar]
- Large, R.R.; Gemmell, J.B.; Paulick, H.; Huston, D.L. The alteration box plot: A simple approach to understanding the relationship between alteration mineralogy and lithogeochemistry associated with volcanic-hosted massive sulfde deposits. Econ. Geol. 2001, 96, 957–971. [Google Scholar] [CrossRef]
- Adam, M.M.; Lv, X.; Fathy, D.; Rahman, A.R.A.A.; Ali, A.A.; Mohammed, A.S.; Farahat, e.s.; Sami, M. Petrogenesis and tectonic implications of Tonian island arc volcanic rocks from the Gabgaba Terrane in the Arabian-Nubian Shield (NE Sudan). J. Asian Earth Sci. 2022, 223, 105006. [Google Scholar] [CrossRef]
- Winchester, J.A.; Floyd, P.A. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chem. Geol. 1977, 20, 325–343. [Google Scholar] [CrossRef] [Green Version]
- Sun, S.S.; McDonough, W.F. Chemical and isotopic systematics of oceanic basalts: Implications for mantle composition and processes. Geol. Soc. Spec. Publ. 1989, 42, 313–345. [Google Scholar] [CrossRef]
- DePaolo, D.J. Neodymiun Isotope Geochemistry: An Introduction; Springer: Berlin, Germany, 1988; pp. 1–189. [Google Scholar]
- DePaolo, D.J. Trace element and isotopic effects of combined wall-rock assimilation and fractional crystallization: Earth Planet. Sci. Lett. 1981, 53, 189–202. [Google Scholar]
- Miller, R.G.; O’Nions, R.K. Source of Precambrian chemical and clastic sediments. Nature 1985, 314, 330. [Google Scholar] [CrossRef]
- Steiger, R.H.; Jäger, E. Subcommission on geochronology: Convention of the use of decay constants in geo- and cosmochronology. Earth Planet. Sci. Lett. 1977, 36, 359–362. [Google Scholar] [CrossRef]
- Woodhead, J.; Eggins, S.; Gamble, J. High field strength and transition element systematics in island arc and back-arc basin basalts: Evidence for multi-phase melt extraction and a depleted mantle wedge. Earth Planet. Sci. Lett. 1993, 114, 491–504. [Google Scholar] [CrossRef]
- Wan, B.; Zhang, L.C. Sr-Nd-Pb isotope geochemistry and tectonic setting of Devonian polymetaUic metallogenic belt on the Southern margin of Altaid, Xingjing. Acta Petrol. Sin. 2006, 22, 145–152. [Google Scholar]
- Pang, C.J.; Wang, X.C.; Li, C.F.; Wilde, S.A.; Tian, L. Pyroxenite-derived Cenozoic basaltic magmatism in central Inner Mongolia, eastern China: Potential contributions from the subduction of the Paleo-Pacific and Paleo-Asian oceanic slabs in the Mantle Transition Zone. Lithos 2019, 332, 39–54. [Google Scholar] [CrossRef]
- Zhang, M.; Guo, Z. Origin of Late Cenozoic Abaga-Dalinuoer basalts, eastern China: Implications for a mixed pyroxenite–peridotite source related with deep subduction of the Pacific slab. Gondwana Res. 2016, 37, 130–151. [Google Scholar] [CrossRef]
- Wang, X.C.; Li, Z.X.; Li, X.H.; Li, J.; Liu, Y.; Long, W.G.; Zhou, J.B.; Wang, F. Temperature, pressure, and composition of the mantle source region of Late Cenozoic basalts in Hainan Island, SE Asia: A consequence of a young thermal mantle plume close to subduction zones? J. Petrol. 2012, 53, 177–233. [Google Scholar] [CrossRef]
- Rehkamper, M.; Hofmann, A.W. Recycled Ocean crust and sediment in Indian Ocean MORB. Earth Planet. Sci. Lett. 1997, 147, 93–106. [Google Scholar] [CrossRef]
- Plank, T.; Langmuir, C.H. The chemical composition of subducting sediment and its consequences for the crust and mantle. Chem. Geol. 1998, 145, 325–394. [Google Scholar] [CrossRef]
- Salters, V.J.M.; Stracke, A. Composition of the depleted mantle. Geochem. Geophys. Geosyst. 2004, 5, Q05B07. [Google Scholar] [CrossRef]
- Zindler, A.; Hart, S. Chemical geodynamics. Annu. Rev. Earth Planet. Sci. 1986, 14, 493–571. [Google Scholar] [CrossRef]
- Hauff, F.; Hoernle, K.; Schmidt, A. Sr-Nd-Pb composition of Mesozoic Pacific oceanic crust (Site 1149 and 801, ODP Leg 185): Implications for alteration of ocean crust and the input into the Izu-Bonin-Mariana subduction system. Geochem. Geophys. Geosyst. 2003, 4, 2002GC000421. [Google Scholar] [CrossRef]
- Othman, D.B.; White, W.M.; Patchett, J. The geochemistry of marine sediments, island arc magma genesis, and crust-mantle recycling. Earth Planet. Sci. Lett. 1989, 94, 1–21. [Google Scholar] [CrossRef]
- Wang, X.C.; Wilde, S.A.; Xu, B.; Pang, C.J. Origin of arc-like continental basalts: Implications for deep-Earth fluid cycling and tectonic discrimination. Lithos 2016, 261, 5–45. [Google Scholar] [CrossRef]
Figure 1.
Geological map of the West Junggar region (modified after Shen et al. [5]).
Figure 1.
Geological map of the West Junggar region (modified after Shen et al. [5]).
Figure 2.
Geological sketch of Shaerbuti Mountain (modified after Sun et al. [13]); The blue stars represent the sample locations for the light rare earth element (LREE)-enriched volcanic rock (type I), and the red stars represent the sample locations for the flat rare earth element (REE)-pattern volcanic rock (type II).
Figure 2.
Geological sketch of Shaerbuti Mountain (modified after Sun et al. [13]); The blue stars represent the sample locations for the light rare earth element (LREE)-enriched volcanic rock (type I), and the red stars represent the sample locations for the flat rare earth element (REE)-pattern volcanic rock (type II).
Figure 3.
Volcanic rock in Shaerbuti Mountain. (a) The studied basalt shows a porphyritic texture with pyroxene and olivine phenocrysts; (b) the studied andesite shows a porphyritic texture with pyroxene phenocrysts; (c) cross polarized images of (a); (d) cross polarized images of (b).
Figure 3.
Volcanic rock in Shaerbuti Mountain. (a) The studied basalt shows a porphyritic texture with pyroxene and olivine phenocrysts; (b) the studied andesite shows a porphyritic texture with pyroxene phenocrysts; (c) cross polarized images of (a); (d) cross polarized images of (b).
Figure 4.
Typical volcaniclastic rock on Shaerbuti Mountain. Breccia (a) and agglomerate (b) of Shaerbuti Mountain; explosive breccia (c–f); (g) volcanic–sedimentary layer.
Figure 4.
Typical volcaniclastic rock on Shaerbuti Mountain. Breccia (a) and agglomerate (b) of Shaerbuti Mountain; explosive breccia (c–f); (g) volcanic–sedimentary layer.
Figure 5.
Alteration box of the selected volcanic rock (after Large et al. [15] and Adam et al. [16]).
Figure 6.
Nb/Y versus Zr/TiO2 diagram of the selected volcanic rocks (after Winchester and Floyd, [17]).
Figure 6.
Nb/Y versus Zr/TiO2 diagram of the selected volcanic rocks (after Winchester and Floyd, [17]).
Figure 7.
(a) REE pattern of the studied Type I volcanic rocks; (b) REE pattern of the studied Type II volcanic rocks. Literature data are derived from Shen et al. [5]. Chondrites values sourced from Sun and McDonough [18].
Figure 8.
(a) Spider diagram of the studied Type I volcanic rocks; (b) Spider diagram of the studied Type II volcanic rocks. Literature data are derived from Shen et al. [5]. NMORB values sourced from Sun and McDonough [18].
Figure 9.
Fractional crystallization discrimination diagram of olivine and clinopyroxenite; (a) represents MgO vs. Cr; (b) represents MgO vs. Ni; (c) represents MgO vs. CaO; (d) represents MgO vs. SiO2. Literature data are derived from Shen et al. [5]. Crystallized trend of minerals sourced from Wang et al. [27].
Figure 9.
Fractional crystallization discrimination diagram of olivine and clinopyroxenite; (a) represents MgO vs. Cr; (b) represents MgO vs. Ni; (c) represents MgO vs. CaO; (d) represents MgO vs. SiO2. Literature data are derived from Shen et al. [5]. Crystallized trend of minerals sourced from Wang et al. [27].
Figure 10.
(a) (87Sr/86Sr)i versus (143Nd/144Nd)i diagram of Shaerbuti volcanic rocks. DM, depleted mantle; AOC, altered oceanic crust. The thick red solid line represents a mixture between the recycled oceanic crust, the AOC (Rehkamper and Hofmann [28]) and the ancient subducted sediment (approximately 1.5 Ga; Rehkamper and Hofmann [28]), and the thick pink solid line represents a mixture between the AOC and subducted modern average Ca-rich sediment (Plank and Langmuir [29]). The dashed line in black indicates 2%, 4% and 6% sediment in the mixture. The thick black and green lines represent the mixing arrays between DM peridotite (Salters and Stracke [30]) and subducted oceanic crust (AOC with 6% of various sediments). The numbers near the gray solid line indicate the percentage of subducted oceanic crust in the source region. (b) (207Pb/204Pb)i versus (206Pb/204Pb)i diagram of the Shaerbuti volcanic rock with a mixture of three end members (DM, sediments and AOC) (after Pang et al. [25]). The compositions of EM1, AOC, and pelagic sediment are from Zindler and Hart [31], Hauff et al. [32], and Othman et al. [33], respectively. Literature data are derived from Shen et al. [5].
Figure 10.
(a) (87Sr/86Sr)i versus (143Nd/144Nd)i diagram of Shaerbuti volcanic rocks. DM, depleted mantle; AOC, altered oceanic crust. The thick red solid line represents a mixture between the recycled oceanic crust, the AOC (Rehkamper and Hofmann [28]) and the ancient subducted sediment (approximately 1.5 Ga; Rehkamper and Hofmann [28]), and the thick pink solid line represents a mixture between the AOC and subducted modern average Ca-rich sediment (Plank and Langmuir [29]). The dashed line in black indicates 2%, 4% and 6% sediment in the mixture. The thick black and green lines represent the mixing arrays between DM peridotite (Salters and Stracke [30]) and subducted oceanic crust (AOC with 6% of various sediments). The numbers near the gray solid line indicate the percentage of subducted oceanic crust in the source region. (b) (207Pb/204Pb)i versus (206Pb/204Pb)i diagram of the Shaerbuti volcanic rock with a mixture of three end members (DM, sediments and AOC) (after Pang et al. [25]). The compositions of EM1, AOC, and pelagic sediment are from Zindler and Hart [31], Hauff et al. [32], and Othman et al. [33], respectively. Literature data are derived from Shen et al. [5].
Table 1.
Major (wt.%) and trace element (ppm) concentrations in the Shaerbuti volcanic rocks.
| Rock Sample | Type I Volcanic Rock | Type II Volcanic Rock | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Basalt | Basalt | Basalt | Basalt | Basalt | Andesite | Andesite | Basalt | Andesite | Andesite | Andesite | |
| HG17-46 | 15BHG45 | 15HG152 | HG2-11 | 15BHG129 | HG17-43 | HG17-2 | 15HG125 | 15HG74-2 | 15HG127 | 15HG76 | |
| SiO2 | 55.46 | 50.54 | 46.94 | 49.22 | 53.02 | 61.79 | 55.64 | 51.7 | 56.7 | 52.26 | 56.21 |
| TiO2 | 0.65 | 0.6 | 0.63 | 0.92 | 0.67 | 0.62 | 0.51 | 1.12 | 0.78 | 0.87 | 0.75 |
| Al2O3 | 16.58 | 13.35 | 21.23 | 15.84 | 16.15 | 15.73 | 17.41 | 17.44 | 17.73 | 15.1 | 17.44 |
| Fe2O3 | 8.38 | 3.01 | 4.48 | 2.27 | 4.19 | 4.36 | 3.59 | 5.96 | 4.4 | 4.39 | 3.84 |
| FeO | 1.77 | 6.49 | 4.68 | 7.28 | 5.06 | 1.55 | 2.93 | 4.17 | 4.14 | 6.1 | 4.1 |
| MnO | 0.11 | 0.18 | 0.14 | 0.28 | 0.15 | 0.1 | 0.14 | 0.18 | 0.15 | 0.19 | 0.15 |
| MgO | 4.51 | 8.14 | 5.12 | 7.31 | 3.74 | 2.92 | 1.51 | 4.95 | 3.26 | 4.93 | 3.35 |
| CaO | 1.32 | 8.95 | 7.09 | 5.88 | 5.97 | 3.23 | 4.32 | 3.79 | 4.91 | 6.84 | 5.35 |
| Na2O | 5.45 | 3.14 | 3.59 | 3.68 | 4.08 | 4.29 | 7.87 | 5.91 | 4.27 | 3.56 | 4 |
| K2O | 1.65 | 1.62 | 1.07 | 2.13 | 2.7 | 2.45 | 1.14 | 0.84 | 1.13 | 1.8 | 0.89 |
| P2O5 | 0.29 | 0.26 | 0.13 | 0.29 | 0.27 | 0.31 | 0.32 | 0.19 | 0.14 | 0.15 | 0.14 |
| LOI | 3.76 | 2.66 | 3.96 | 3.96 | 3.3 | 2.6 | 4.3 | 3.36 | 2.08 | 2.58 | 2.46 |
| TOTAL | 99.92 | 98.94 | 99.06 | 99.06 | 99.30 | 99.95 | 99.68 | 99.61 | 99.69 | 98.77 | 98.68 |
| Mg # | 0.82 | 0.69 | 0.66 | 0.64 | 0.57 | 0.77 | 0.48 | 0.68 | 0.58 | 0.59 | 0.59 |
| Cr | 46.8 | 255 | 48.2 | 126 | 41.9 | 20.6 | 25.6 | 50.6 | 5.29 | 32.1 | 5.25 |
| Co | 29.9 | 37.8 | 32.1 | 46.6 | 34.5 | 18.3 | 18.8 | 33.3 | 25.7 | 27.5 | 23.4 |
| Ni | 11.3 | 25.8 | 15.8 | 29.2 | 11.9 | 11.4 | 3.52 | 16.8 | 5.24 | 16.1 | 5.55 |
| Ga | 15.3 | 14.3 | 19.4 | 16.3 | 17.4 | 12.4 | 16.8 | 17.5 | 19.9 | 14 | 18.7 |
| Rb | 22.1 | 34.2 | 11.4 | 40.2 | 32.9 | 43.7 | 11.2 | 10.9 | 11.6 | 16.8 | 8 |
| Sr | 353 | 306 | 626 | 483 | 659 | 516 | 214 | 678 | 443 | 307 | 440 |
| Y | 15.7 | 15.5 | 16.5 | 24.4 | 19.8 | 16.3 | 32.5 | 36.5 | 31.3 | 18.2 | 30.1 |
| Nb | 4.49 | 3.48 | 2.07 | 3.44 | 3.76 | 4.21 | 5.35 | 3.68 | 3.5 | 1.82 | 3.3 |
| Cs | 0.41 | 0.44 | 0.55 | 1.03 | 0.56 | 0.9 | 0.09 | 0.54 | 0.25 | 0.61 | 0.26 |
| Ba | 312 | 251 | 394 | 698 | 520 | 461 | 196 | 414 | 508 | 370 | 375 |
| La | 10.4 | 12.5 | 6.14 | 12.1 | 14 | 12.8 | 14.5 | 8.1 | 7.24 | 5.71 | 6.82 |
| Ce | 21.4 | 24.3 | 14.1 | 27.5 | 26.7 | 25.9 | 30.7 | 19.9 | 16.8 | 12.7 | 16.2 |
| Pr | 2.93 | 3.32 | 2.05 | 3.96 | 3.56 | 3.51 | 4.32 | 3.13 | 2.58 | 1.84 | 2.48 |
| Nd | 13.4 | 15.2 | 10.3 | 18.7 | 16 | 16.1 | 19 | 15.7 | 12.8 | 9.06 | 12.1 |
| Sm | 3.12 | 3.42 | 2.7 | 4.64 | 3.47 | 3.56 | 4.47 | 4.41 | 3.57 | 2.35 | 3.29 |
| Eu | 0.8 | 1.01 | 0.86 | 1.26 | 1.02 | 0.94 | 1.27 | 1.27 | 1.06 | 0.73 | 1.03 |
| Gd | 2.6 | 2.86 | 2.44 | 4.18 | 3.14 | 2.97 | 4.28 | 4.56 | 3.69 | 2.31 | 3.55 |
| Tb | 0.5 | 0.52 | 0.5 | 0.79 | 0.6 | 0.56 | 0.89 | 1.01 | 0.85 | 0.51 | 0.83 |
| Dy | 2.8 | 2.77 | 2.97 | 4.47 | 3.4 | 2.97 | 5.19 | 6.15 | 5.31 | 3.09 | 5.13 |
| Ho | 0.6 | 0.57 | 0.62 | 0.9 | 0.71 | 0.6 | 1.15 | 1.34 | 1.17 | 0.66 | 1.11 |
| Er | 1.67 | 1.58 | 1.68 | 2.37 | 1.93 | 1.7 | 3.19 | 3.45 | 3.18 | 1.78 | 3.15 |
| Tm | 0.3 | 0.27 | 0.31 | 0.44 | 0.37 | 0.28 | 0.6 | 0.66 | 0.6 | 0.32 | 0.6 |
| Yb | 1.97 | 1.71 | 1.87 | 2.61 | 2.31 | 1.86 | 3.98 | 4.11 | 3.77 | 2.1 | 3.7 |
| Lu | 0.29 | 0.25 | 0.27 | 0.38 | 0.35 | 0.28 | 0.62 | 0.61 | 0.55 | 0.32 | 0.58 |
| Ta | 0.61 | 0.43 | 0.32 | 0.29 | 0.31 | 0.38 | 0.64 | 0.4 | 0.4 | 0.23 | 0.36 |
| Pb | 3.23 | 1.94 | 2.91 | 1.46 | 7.64 | 5.18 | 2.16 | 4.75 | 3.33 | 4.42 | 3.64 |
| Th | 2.39 | 1.88 | 0.94 | 1.65 | 2.5 | 2.71 | 2.4 | 1.03 | 0.96 | 0.95 | 0.91 |
| U | 3.82 | 0.99 | 0.69 | 0.98 | 1.72 | 2.05 | 1.33 | 0.82 | 1.18 | 0.74 | 1.02 |
| Zr | 57.2 | 45.1 | 47.4 | 67.5 | 59.2 | 57.6 | 121 | 108 | 111 | 56.4 | 107 |
| Hf | 1.8 | 1.49 | 1.58 | 2.15 | 1.91 | 1.9 | 3.34 | 3.35 | 3.43 | 1.83 | 3.28 |
| Th/Nb | 0.53 | 0.54 | 0.46 | 0.48 | 0.66 | 0.64 | 0.45 | 0.28 | 0.27 | 0.52 | 0.27 |
| Rb/Y | 1.41 | 2.21 | 0.69 | 1.65 | 1.66 | 2.68 | 0.34 | 0.3 | 0.37 | 0.92 | 0.27 |
| Nb/Zr | 0.08 | 0.08 | 0.04 | 0.05 | 0.06 | 0.07 | 0.04 | 0.03 | 0.03 | 0.03 | 0.03 |
| Zr/Nb | 12.74 | 12.96 | 22.9 | 19.62 | 15.74 | 13.68 | 22.62 | 29.35 | 31.71 | 30.99 | 32.42 |
| (La/Sm)N | 3.33 | 3.65 | 2.27 | 2.61 | 4.03 | 3.6 | 3.24 | 1.84 | 2.03 | 2.43 | 2.07 |
| (La/Yb)N | 5.28 | 7.31 | 3.28 | 4.64 | 6.06 | 6.88 | 3.64 | 1.97 | 1.92 | 2.72 | 1.84 |
| (Gd/Yb)N | 1.32 | 1.67 | 1.3 | 1.6 | 1.36 | 1.6 | 1.08 | 1.11 | 0.98 | 1.1 | 0.96 |
| Th/Yb | 1.21 | 1.1 | 0.5 | 0.63 | 1.08 | 1.46 | 0.6 | 0.25 | 0.25 | 0.45 | 0.24 |
| Nb/Yb | 2.28 | 2.04 | 1.11 | 1.32 | 1.63 | 2.26 | 1.34 | 0.9 | 0.93 | 0.87 | 0.89 |
Mg# = MgO/(FeO + MgO).
Table 2.
Rb-Sr-Sm-Nd isotopes of the Shaerbuti volcanic rocks.
| Sample Number | Rock Type | Rb (×10−6) | Sr (×10−6) | 87Rb/86Sr | (87Sr/86Sr)m | 2δ(×10−6) | (87Sr/86Sr)i | εSr(t) | Sm (×10−6) | Nd (×10−6) | 147Sm/144Nd | (143Nd/144Nd)m | 2δ(×10−6) | (143Nd/144Nd)i | εNd(t) | TDM |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 15BHG45 | Type I volcanic rock | 32.46 | 324.8 | 0.2893 | 0.707082 | 14 | 0.705227 | 18.441707 | 3.268 | 14.19 | 0.1394 | 0.512805 | 8 | 0.512394 | 6.55 | 709 |
| 15HG127 | Type II volcanic rock | 20.13 | 419.3 | 0.1390 | 0.705466 | 10 | 0.704575 | 9.158643 | 2.838 | 10.51 | 0.1635 | 0.512876 | 11 | 0.512394 | 6.55 | 833 |
| 15HG74-2 | Type II volcanic rock | 13.65 | 601 | 0.0657 | 0.705048 | 12 | 0.704626 | 9.882972 | 4.302 | 14.91 | 0.1747 | 0.512905 | 8 | 0.512391 | 6.49 | 955 |
| 15HG76 | Type II volcanic rock | 7.811 | 488.7 | 0.0463 | 0.704924 | 13 | 0.704628 | 9.907471 | 3.366 | 11.7 | 0.1742 | 0.512901 | 9 | 0.512387 | 6.42 | 963 |
| 15HG17-43 | Type I volcanic rock | 7.385 | 565.6 | 0.0378 | 0.706602 | 12 | 0.706359 | 34.504278 | 3.345 | 14.94 | 0.1356 | 0.512796 | 8 | 0.512397 | 6.61 | 690 |
Rb, Sr, Sm and Nd are in ppm. (m) represents the measured value, (i) represents the initial value, and (t) is the idealized crystallization age (450 Ma). The 87Sr/86Sr values are normalized to 86Sr/88Sr = 0.1194, and the 143Nd/144Nd values are normalized to 146Nd/144Nd = 0.7219. ε Nd(t) = [{(143Nd/144Nd)m/(143Nd/144Nd)CHUR} − 1] × 104, using (143Nd/144Nd)CHUR = 0.512638 [19]. Initial (i) values calculated at 450 Ma. ε Sr(t) = [{(87Sr/86Sr)m/(87Sr/86Sr)CHUR} − 1] × 104, using (87Sr/86Sr)CHUR = 0.7045 [20]. The model age was calculated by a linear isotopic ratio growth equation: t DM = (1/λ) * ln{1 + [(143Nd/144Nd)m − 0.51315]/[(147Sm/144Nd)m − 0.2137] (0.51315 and 0.2137 from [21]). The decay constants that were used are 1.42 × 10−11 a−1 for 87Rb, 6.54 × 10−12 a−1 for 147Sm, 238U = 1.55125 × 10−10 a−1, 235U = 9.8485 × 10−10 a−1 and 232Th = 4.9475 × 10−11 a−1 [22].
Table 3.
Pb isotopes of the Shaerbuti volcanic rocks.
| Sample Number | Rock Type | U | Th | Pb | 238U/204Pb | 235U/204Pb | 232Th/204Pb | (206Pb/204Pb)m | (207Pb/204Pb)m | (208Pb/204Pb)m | (206Pb/204Pb)i | (207Pb/204Pb)i | (208Pb/204Pb)i |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 15BHG45 | Type I volcanic rock | 0.99 | 1.88 | 1.94 | 36.186 | 0.262 | 69.219 | 20.964 | 15.681 | 39.549 | 18.348 | 15.535 | 37.991 |
| 15HG127 | Type Ⅱ volcanic rock | 0.743 | 0.948 | 4.42 | 11.920 | 0.086 | 15.320 | 18.756 | 15.576 | 38.159 | 17.894 | 15.528 | 37.814 |
| 15HG125 | Type Ⅱ volcanic rock | 0.824 | 1.03 | 4.75 | 12.301 | 0.089 | 15.489 | 18.657 | 15.571 | 38.255 | 17.768 | 15.521 | 37.906 |
| 15HG74-2 | Type Ⅱ volcanic rock | 1.18 | 0.958 | 3.33 | 25.128 | 0.182 | 20.549 | 18.869 | 15.556 | 38.163 | 17.052 | 15.454 | 37.700 |
| 15HG76 | Type Ⅱ volcanic rock | 1.02 | 0.906 | 3.64 | 19.871 | 0.144 | 17.779 | 18.715 | 15.553 | 38.132 | 17.278 | 15.473 | 37.732 |
| HG17-43 | Type I volcanic rock | 2.05 | 2.71 | 5.18 | 28.063 | 0.204 | 37.369 | 19.159 | 15.573 | 38.449 | 17.130 | 15.460 | 37.608 |
U, Th and Pb are in ppm. (m) represents the measured value, and (i) represents the initial value. Initial (i) values calculated at 450 Ma. The decay constant is used for 238U = 1.55125 × 10−10 a−1, 235U = 9.8485 × 10−10 a−1 and 232Th = 4.9475 × 10−11 a−1 [22].
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
MDPI and ACS Style
Sun, J.; Li, N.; Dong, C.; Ren, Y. Geochemical Features of Volcanic Rocks from the Shaerbuti Mountain Complex, West Junggar, Xinjiang, China: Implications for Recycling of Materials. Minerals 2023, 13, 75. https://doi.org/10.3390/min13010075
AMA Style
Sun J, Li N, Dong C, Ren Y. Geochemical Features of Volcanic Rocks from the Shaerbuti Mountain Complex, West Junggar, Xinjiang, China: Implications for Recycling of Materials. Minerals. 2023; 13(1):75. https://doi.org/10.3390/min13010075
Chicago/Turabian StyleSun, Jinheng, Ni Li, Cheng Dong, and Yanhong Ren. 2023. "Geochemical Features of Volcanic Rocks from the Shaerbuti Mountain Complex, West Junggar, Xinjiang, China: Implications for Recycling of Materials" Minerals 13, no. 1: 75. https://doi.org/10.3390/min13010075
Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.
