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A geochronological study of granite and related mineralization of the Zhangjiadi molybdenite-tungsten deposit in Xingguo County, southern Jiangxi Province, China, and its geological significance

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Abstract

The Xingguo-Ningdu ore cluster in southern Jiangxi Province, located in the convergent zone of the eastern Nanling EW-trending metallogenic belt and the western Wuyishan NE-trending metallogenic belt, possess several different type of W-Sn polymetallic deposits. However, little research has been done for these deposits. Based on detailed field investigations, high-precision isotope dating on the Zhangjiadi Mo-W deposit, the time-space distribution of W-Sn ore deposits in Cathaysia Block and their geodynamic settings are studied in this paper. SHRIMP zircon U-Pb age for porphyritic fine to medium-grained biotite granite from the Zhangjiadi ore deposit is 154.1 ± 1.8Ma. Molybdenites separated from the quartz vein type orebody in the Wangnipai ore block and the greisen orebody in the Liujiazhuang ore block yield Re-Os isochron ages of 158.4 ± 3.1Ma (weighted mean age 157.7 ± 1.4Ma) and 161.9 ± 3.2Ma (weighted mean age 157.9 ± 1.6Ma), respectively, which are corresponding to Late Jurassic period. The studied molybdenites show quite low Re contents (9.58 × 106 - 22.65 × 106), suggesting a continental crustal source of the ore metals. Integrated with the latest research results, it is concluded that the W-Sn deposits formed during 240-210Ma, 170-150Ma and 130-90Ma, and are centered by the largest scale in southern Jiangxi Province and southern Hunan Province, and become younger in the east, west, south and north directions. We suggest that the Yanshanian large-scale magmatic and ore-forming processes may have occurred in a Jurassic intraplate extensional geodynamic setting during the Mesozoic lithosphere extension in South China.

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... Recently, with the expansion of the research scope and the progress of research techniques and methods, Indosinian granites and related W mineralization in the Nanling metallogenic belt, and even in the whole of South China, have been reported in an increasing number of papers [12][13][14][15][16][17]. Indosinian metallogenic events are considered to have good metallogenic potential, and the prospecting work carried out on Indosinian deposits should be strengthened [18][19][20][21][22]. ...
... [30]). (B) Schematic distribution map of tungsten ore cluster and typical W-Sn deposits in South Jiangxi Province (modified from [18]). (C) Regional geological map of Baishi W-Cu deposit (modified from [31]). ...
... In recent years, increasing numbers of researchers have discovered Indosinian tungsten deposits in the Nanling region based on the quick development of dating technology [12-17, this study]. In addition, more scholars have realized that the tungsten mineralization in the Nanling region is characterized by multiple stages [4,18]. Mao et al. [4] systematically summarize the high-precision isotopic chronology data published in recent years and divide the Mesozoic tungsten polymetallic mineralization in the Nanling region into ...
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The Baishi W-Cu deposit is located in the Nanling metallogenic belt, which is famous for its numerous W deposits and reserves. The formation age of this deposit remains unclear. In order to further infer the formation age of the deposit, this study conducted detailed LA-ICP-MS U-Pb isotopic analyses of zircon and monazite selected from ore-related Baishi granite. The LA-ICP-MS zircon U-Pb weighted average ages of Baishi granite were determined to be 223 ± 2 Ma and 226 ± 1 Ma, and the LA-ICP-MS U-Pb weighted average ages of monazite were determined to be 224 ± 2 Ma and 223 ± 1 Ma. The BSE image of monazite was homogeneous, and the pattern of rare earth elements had an obvious negative Eu anomaly, indicating that monazite was of magmatic origin. Combining the ages of zircon and monazite, this study inferred that Baishi granite and the Baishi W-Cu deposit formed in the Triassic. The determination of the ore-forming event of the Baishi W-Cu deposit provides new data regarding the important Indosinian (Triassic) mineralization events in the Nanling metallogenic belt and suggests that geologists should strengthen the prospecting work of Indosinian tungsten deposits in the Nanling area. In terms of tectonic setting, it was inferred that the Triassic Baishi W-Cu deposit was formed in the extensional environment after intracontinental orogeny.
... In Fujian Province, several Jurassic deposits are recognized, such as the Gutian porphyry Cu-Mo deposit (Huang et al., 2021;Li et al., 2016), the Xingluokeng W deposit of 156.3 ± 4.8 Ma , and the Shankou porphyry Mo deposit of 165.3 ± 3.5 Ma (Luo et al., 2009). Jiangxi Province produces the most Mo-W deposits in South China, and the representative deposits include the Lianhuaxin quartz vein Cu-Mo-W deposit of 158.6 ± 2.0 Ma , the Zhangjiadi quartz vein Mo-W deposit of~160 Ma (Feng et al., 2015), the Yashan quartz vein W-Mo deposit of 156.0 ± 2.8 Ma (Yi et al., 2015), the Xiatongling quartz vein W-Mo-Bi-Be deposit of 156.4 ± 8.7 Ma (Yi et al., 2015), the Shizitou quartz vein Mo deposit of~160 Ma (Ni et al., 2017;Shao et al., 2018), the Xiongjiashan porphyry Mo deposit of 152 ± 20 Ma (Meng et al., 2007), the Yuanlingzhai porphyry Mo deposit of 161.1 ± 3.9 Ma , and the Getingkeng porphyry Mo deposit of 159.4 ± 1.6 Ma . In Hunan Province, the Gaoaobei quartz vein W-Mo deposit of 157.3 ± 6.6 Ma was formed . ...
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South China developed large-scale Mesozoic magmatism and polymetallic mineralization, especially Jurassic W-Sn and Mo-W mineralization. Compared with W-Sn deposits, Mo-W deposits in South China have received less attention. The recently discovered Gangmei Mo-W deposit, which occurred in Guangdong Province, is the southernmost Jurassic Mo-W mineralization in South China. Here, we report the molybdenite Re-Os isotopic age of the Gangmei deposit and compile the Mo-W- and W-Sn-associated deposits in South China and their Re concentrations in molybdenites, aiming at constraining the ore-forming age of the Gangmei deposit, the scope of Mo-W mineralization in South China and the possible controlling factors of different mineralization types. Four molybdenite samples from the Gangmei deposit were chosen for Re-Os isotopic dating. The Re-Os model ages vary from 162.6 ± 1.6 Ma to 164.1 ± 1.6 Ma with a weighted mean age of 163.1 ± 1.4 Ma and yield an isochron age of 162.2 ± 4.1 Ma (MSWD = 1.01), consistent with the emplacement age of the Gangmei intrusion, indicating a genetic relationship between magmatic activity and mineralization. This age also agrees well with the large-scale Jurassic Mo-W- and W-Sn-associated mineralization in South China, suggesting that the scope of Jurassic Mo-W-associated mineralization can reach the southernmost part of South China. Rhenium concentrations in molybdenites from Jurassic Mo-W-associated and W-Sn-associated deposits in South China suggest that their magma sources are different, and Mo-W-associated deposits may involve more mantle-derived materials. In addition, oxygen fugacity may be another factor controlling different types of mineralization in South China.
... Histograms of the precise petrogenetic and metallogenic ages from different dating methods for the W-Sn polymetallic deposits in southern Jiangxi provinces. The data sources of the different W -Sn polymetallic deposits listed in Supplementary Table S3 are from Chen et al. (2006), Zhang et al. (2006), Liu et al. (2008, 2010a, 2010b, Feng et al. (2011aFeng et al. ( , 2011bFeng et al. ( , 2011cFeng et al. ( , 2012bFeng et al. ( , 2012cFeng et al. ( , 2015aFeng et al. ( , 2015b, Guo et al. (2011Guo et al. ( , 2012 magmatism is consistent with the age of the tungsten-tin mineralization . This suggests that longterm and contemporaneous multistage magmatism formed the multistage mineralization, and the Early Cretaceous (~142 Ma) may have been an important stage of granitic magmatism and mineralization in southern Jiangxi Province, even in South China Block. ...
Article
Mesozoic magmatism and associated mineralization are widespread in the South China Block (SCB). Tungsten-polymetallic deposits in the Nanling Range within the central SCB represent one of the most important tungsten regions in the world. The Huangsha-Tieshanlong W deposit is an important large quartz vein-type W-polymetallic deposit in southern Jiangxi Province, in the eastern Nanling Range. Zircon U-Pb analyses of six representative samples of the ore-related granitoids from a tunnel in the Huangsha-Tieshanlong W deposit yielded ages of 152.2 ± 3.8 Ma, 154.0 ± 2.8 Ma, 150.4 ± 4.6 Ma, 151.3 ± 2.7 Ma, 141.6 ± 4.2 Ma, and 142.1 ± 4.6 Ma. These granitoids have low εHf(t) values (−15.7 to −7.6), and old two-stage model ages (1746–1347 Ma), indicating that they were derived from the partial melting of Proterozoic crustal materials. These ages combined with other geochronological data in the region suggest that the Huangsha-Tieshanlong pluton was formed by at least three stages of granitic magmatism during the Middle Jurassic (~168 Ma), Late Jurassic (~152 Ma), and Early Cretaceous (~142 Ma), which coincides with the formation ages of the W-Sn deposits at 171–160 Ma, 159–150 Ma, and 149–144 Ma, respectively. Thus, the intrusion of the granite and the associated W-Sn mineralization in the Huangsha-Tieshanlong deposit occurred almost synchronously. It is worth noting that our study indicates that the Early Cretaceous (~142 Ma) is probably another important stage of granitic magmatism and mineralization in the eastern Nanling region.
... Three dominant peaks occur at ca. 350, 450, and 1,010 cm −1 , with F I G U R E 1 0 Comparison of precise petrogenetic and metallogenic ages by different dating methods from the W-Sn polymetallic deposits in the southern Jiangxi provinces. The data sources of different W-Sn polymetallic deposits are from Chen et al. (2006), Zhang et al. (2006;), Liu et al. (2008, Liu et al. (2010a), Feng et al. (2011a, 2011b, 2011c, 2012a, 2012b, 2015a, 2015b, Guo et al. (2011; Table 2 F I G U R E 8 (a) Discrimination diagram of the Ce anomaly (Ce/Ce*) versus (Sm/La) N and (b) the chondrite-normalized Sm-La ratio versus La to discriminate magmatic and hydrothermal zircon as defined by Hoskin (2005) F I G U R E 9 Geochronology framework of the Xihuashan and Tieshanlong W-polymetallic deposits and associated granitic magmatism in the southern Jiangxi Province. Age data in the Xihuashan mining district are from Wang et al. (2011), Guo et al. (2012, Hu et al. (2012), and this study; those in the Tieshanlong mining district are from Huang et al. (2011), Li (2011, and this study the most intense peak at 1,010 cm −1 . ...
Article
The Xihuashan and Tieshanlong tungsten deposit is an important large quartz vein‐type W‐polymetallic deposit in the southern Jiangxi Province, eastern Nanling Range. Zircon U–Pb analyses of representative ore‐forming granites from the Xihuashan and Tieshanlong tungsten deposit yield ages of 146.3 ± 2.9 Ma and 146.0 ± 3.8 Ma, respectively. According to the zircon Raman spectroscopy, these granitic rocks are disturbed by different degrees of hydrothermal alteration, whereas most zircons exhibit primary oscillatory zoning and Th/U ratios in the range of magmatic zircon, which means the analysis results represent the crystallization age of metallogenetic granitic assemblages. In combination with regional geological data, it is suggested that the Late Jurassic is probably another important episode of granitic magmatism and W‐Sn mineralization in southern Jiangxi Provinces, even South China. Zircon U‐Pb analyses of representative ore‐forming granites from the Xihuashan and Tieshanlong tungsten deposit yield ages of 146.3 ± 2.9 and 146.0 ± 3.8 Ma, respectively. According to the zircon Raman spectroscopy, these granitic rocks are disturbed by different degrees of hydrothermal alteration. It is suggested that the Late Jurassic is probably another important episode of granitic magmatism and W‐Sn mineralization in southern Jiangxi Provinces, even south China.
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The Dongpo ore field is in the western part of the Nanling polymetallic metallogenic belt, which is located in the intersection between Yangtze block and Cathaysian block. There are a series of large-and medium-sized W-Sn-Mo-Bi polymetallic deposits distributed around the Qianlishan granite in the Dongpo ore field. The Jinchuantang deposit is a large-sized skarn-type tin- bismuth deposit in the Dongpo ore field.Direct Re-Os dating on molybdenites collected from the skarn ore in the Jinchuantang deposit have been carried out, in order to further restrict the age of mineralization. The results show that Re-Os model ages range from 157.2 ±2.8Ma to 162.4 ±2.4Ma, with an average of 159.8 ±2.9Ma, and give an isochron age of 158.8 ±6.6Ma.Combined with the Re- Os isochron age (151.0 ± 3.5Ma) of Shizhuyuan deposit and zircon SHRIMP U-Pb ages ( 152 ± 2Ma) of the Qianlishan granite, it is suggested that the mineralization of the Jinchuantang Sn-Bi deposit is temporally and genetically related to the granite in this area. Based on previous studies, petrologenesis and metallogenesis of the Dongpo ore field, including the Jinchuantang deposit, mainly occurred 149 ∼ 161Ma, which is similar to the large-scale tungsten-tin polymetallic mineralization (150 ∼ 160Ma) in the Nanling region. Coupled with previous studies in this region, it is suggested that mantle components were extensively involved in the petrologenic and metallogenic processes of the Mesozioc W-Sn polymetallic ore district, southern Hunan Province, indicating that the Middle-Late Jurassic explosive mineralization of this region is probably as results of crust-mantle interactions under a geodynamic setting of the lithospheric thinning and extension.
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The Qitianling granitic stock is located in the southeast Hunan Province, South China. Recently, a giant tin deposit, the Furong, has been found in the southern part of the granite. This granite stock can be divided into three units: the Cailing, Furong and Huangtangling granites. Detailed SHRIMP U-Pb geochronology of zircons from the Furong granite is reported in this paper, which yield 206Pb/238U ages of 155.5 ± 1.3 Ma (MSWD = 1.7) and 157.1 ± 1.2 Ma (MSWD = 1.7), respectively. This age is consistent with that of the Cailing granites (159 ∼ 160 Ma), suggesting both of them were emplaced at the same time. Inherited zircon cores yield Paleo- and Meso-Proterozoic ages of 2445 ± 29 Ma and 1708 ± 23 Ma, indicating the presence of Paleo- to Meso-Proterozoic component in the deep crust of this region. An inherited metamorphic zircon was found which yields an age of 907 ± 4.8 Ma, which is consistent with the age of collision between Yangtze Block and Cathaysia Block. These data further support that the high εNd (t) and low TDM Shi-Hang belt in South China may have originated from a collision zone during Neoproterozoic time between Yangtze and Cathaysia blocks.
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The Xintianling tungsten deposit is a large-sized skarn and vein-type tungsten-molybdenum polymetallic deposit located in southern Hunan Province, which is genetically associated with the early stage hornblende-biotite monzonitic granite of Qitianling pluton. Direct Re-Os dating on molybdenites collected from the skarn and quartz-vein type ore in the Xintianling deposit have been carried out, to better understand the age of mineralization. The results show that the Re-Os dating of one molybdenite sample collected from skarn- type ore yields a 187Re- 187 Os model age of 159.1 ± 1.9Ma, and six molybdenite samples collected from quartz-vein-type ore yield 187Re- 187Os model ages ranging from 159.1 ± 1.9Ma to 160.2 ±2.9Ma, with an average of 159.4 ± 1.3Ma, and give an isochron age of 161.7 ±9.3Ma (2σ) , with an initial 187Os of 0.6 ±2.3 ( MSWD =0.051). Comparison of the Re-Os ages with published Ar-Ar date ( 157.1 ± 0.3Ma) on iron mica and Rb-Sr date( 157.4 ± 3.2Ma) on quartz indicates that the timing of skarnization and tungsten- molybdenum mineralization are identical within error. Therefore, we can constrain the absolute age of tungsten-molybdenum mineralization in the Xintianling deposit at ca.161.7 ∼ 157.IMa. These ages are consistent with the SHRIMP zircon U-Pb ages (163 ∼ 160Ma) of the early stage hornblende-biotite monzonitic granite. Based on previous studies, it is suggested that the mineralization of the Xintianling W-Mo deposit is spatially and temporally related to the early stage hornblende-biotite monzonitic granite of Qitianling pluton.While the Furong tin deposit located in southern part of Qitianling pluton may be closely related to the late stage biotite monzonitic granite. The emplacement of the Qitianling A-type granite and associated tungsten-tin polymetallic mineralization is a continuous evolution process, which are the products of large-scale mineralization of the Nanling in Middle-Late Jurassic (150 ∼160Ma). Under the tectonic setting of Mesozoic lithospheric extension, asthenosphere upwelling along deep fault, intensive mantle-crust interaction processes probably provide not only the high heat flow, but also part mantle-derived material for large-scale W-Sn-polymetallic mineralization in this area.
Article
K/Ar dates of volcanic rocks, biotite-granite and greisens from this deposit in the Guangdong Province of China are reported. The whole-rock isochron ages of the volcanic rocks are within the range 120.4 + or - 12.1 m.y. The petrogenetic age of the biotite-granite and the minerogenetic age of the W ore deposit are close to those of the volcanic rocks. The apparent age of various types of rocks in the mining district generally bias towards younger values, which may be attributed to the effects of late thermal events in the circum-Pacific metallogenetic belt.-P.Br.
Article
There are many quartz vein-type tungsten polymetallic ore deposits in northern Guangdong which can be divided into two types according to their wall rocks. One type of the ore deposits is hosted in the Cambrian sandstones and coarse-grained granite while the tungsten polymetallic mineralization is closely related to the fine-grained granite, which is represented by the Miantuwo tungsten deposit. The age of fine-grain granite is dated to be 146.95±0.84 Ma/153.82±0.96 Ma, using zircon U-Pb method, while the molybdenite Re-Os isochrone and biotite Ar-Ar isochrone are 150.5±1.4 Ma and 151.0±1.2 Ma respectively, and thus the Miantuwo deposit was formed in the Late Jurassic. The other type of the ore deposits is hosted in the Devonian limestones with the Heshangtian tungsten deposit as a representative. The after type of ore deposits is different from the one aforementioned. 39Ar/40Ar dating of the micas from the Heshantian deposit shows that the mineralization age is 161.1±1.1 Ma, i.e., the deposit was also formed in the Late Jurassic. That is the quartz vein tungsten ore deposits in northern Guangdong are closely related to the Late Jurassic granites. Indosinian granites and the Devonian limestones can be the country rocks of the ore veins in northern Guangdong, and therefore, attentions should be paid to above two types of country rocks in the future explorations.
Article
The Liangcun granites outcrop within Liangcun town, Xingguo county, in the south of Jiangxi province. The Liangcun granites are product of the PhaseImagmatism of the Early Yanshanian, displaying characteristics of syn-tectonic granite. The batholith consists mainly of biotite-granite which is intruded by the latter stages of dimicaceous-granite and granodiorite. The Liangcun granites are peraluminous to strongly peraluminous, and show LREE enriched patterns. The Liangcun granites are "S-type" or crustal remelting granite derived from low degree partial melting of crustal materials. The LA-ICP-MS zircon U-Pb dating results of 4 granite samples indicate that the Liangcun granites were emplaced at 158 to 147 Ma, i.e., the Late Jurassic. The cooling and crystallization of the Liangcun granites may have lasted ~10 Ma as suggested by the isotopic ages.
Article
The newly discovered large-scale Shangfang tungsten deposit represents a new type of tungsten mineralization in Fujian Province offering new pespectives for exploration of tungsten deposits in the province. The ore bodies are mostly hosted in amphibolite and biotite leptynite of the Paleoproterozoic Dajinshan Formation proximal to the Shangfang syenogranite intrusion and less significantly, in the contact zone between the intrusion and the metamorphic rocks. Tungsten mineralization consists of quartz-scheelite veins and disseminated scheelite in alteration assemblages, with scheelite and molybdenite as the main ore minerals coexisting with minor pyrrhotite, pyrite, and chalcopyrite. Field relations and petrographic characterization indicate that the Shangfang deposit is typified by skarn mineralization. Zircons from the Shangfang syenogranite intrusion have LA-ICP-MS U-Pb age of 158.8±1.6 Ma (1σ), whereas five molybdenite separates yield model ages ranging from 159.40±0.86 to 149.92±1.39 Ma with a weighted mean of 156.5 ± 4.0 Ma which is consistent with an isochrone age of 158.1±5.4 Ma (2σ). The geochronological data thus demonstrate that the Shangfang tungsten deposit formed in the Late Jurassic and is genetically related to the syenogranite intrusion in the mine. The data also indicate that the Shangfang deposit resulted from the pervasive Late Mesozoic tunsgten mineralization in South China. It has long been considered that the Late Jurassic tungsten metallogenic belt in South China is restricted in the middle-eastern portion of the Nanling Range covering areas of southern Hunan northern Guangdong, and southern Jiangxi Province. The discovery of the Shangfang deposit, however, allows this metallogenic belt to extend into western and northern Fujian Province which is an integral part of the Wuyishan metallogenic belt. As such, the South China polymetallic belt is distributed along a northeast strike, rather than an east-west extension as previously thought and can be regarded as an important part of the giant Circle-Pacific tectono-magmtic-metallogenic domain.
Article
The porphyritic granite containing high tungsten content (typically several hundreds of X 10) is discovered in the Dahutang area, Jiangxi Province, South China. The tungsten content is dozens to hundreds of times higher than the normal barren granites. In this paper, we reported detailed studies on the LA-ICP-MS zircon U-Pb dating, major elements, trace elements, zircon Hf isotopic compositions and whole-rock Nd isotopic compositions of the tungsten-bearing porphyritic granite. The studies of petrography and geochemistry of this rock indicate that it is highly fractional S-type granite, possessing the characteristics of silica-rich, high alkalinity, high Ga/Al ratios, low zircon saturation temperatures, enrichment in LILEs and depletion in HFSEs and significant negative Eu anomalies. Hence, this rock belongs to peraluminous granite. Its εNd(t) and εHf(t) values varied from -7.45 to -8.20 and from -2.43 to -8.23, respectively, and the calculated two-stage model ages (tDM) of Nd and Hf isotopes are as 1534 ∼ 1595Ma and 1312 ∼ 1677Ma, respectively. Coupled with the values of CaO/Na2O (< 0.3), these data suggest that pelitic metasediments of Proterozoic Shuangqiaoshan Group may be the source rocks for the porphyritic granite. The porphyritic granite shows typical geochemical features of Li-, and Rb-rich, Ba-, Zr-, and ΣREE-depletion, with the GCI values >0. The values of Ba/Rb <0.6 and Rb/Zr > 6 can be used to distinguish the tungsten-bearing granite from the barren granite. It is likely that the magma had extracted tungsten from the tungsten-rich Shuangqiaoshan Group metasedimentary rocks during partial melting of these source rocks. Extreme fractional crystallization resulted in further enrichment of tungsten in the evolved granitic magma which led to later precipitation of tungsten from the magmatic-hydrothermal fluids.
Article
The Dahutang tungsten (molybdenum, copper, tin) ore fields are located in the middle part of the Jiangnan Orogen which is the junction of three counties of Wuning, Xiushui, Jing'an area in the middle of the northern part of Jiuling Mountains. It is the world's largest tungsten mine. In this paper, we study the mineral chemistry, major elements, trace elements, and Sr-Nd isotopic compositions of the porphyric-like muscovite granite which is closely related to mineralization in the deposit. The results show that LA-ICP-MS zircon U-Pb age of the porphyric-like muscovite granite is 144.2 +/- 1.3Ma. The muscovite in the granite belongs to primary magmatic muscovite, and the biotite shows iron-rich characteristic, and its composition indicates a crust origin of the rock. The Fe3+/Fe2+ composition of biotite indicates a low oxygen fugacity for the magma evolution. The porphyric-like muscovite granite belongs to S-type granite which is characterized by high SiO2(72.88% to 73.33%), strongly peraluminous, low Nb and Ta, high Rb/Sr, strong LREE/HREE fractionation, and pronounced negative Eu anomalies. The epsilon(Nd)(t) values of the rock varied from -7.47 to 7.78 with the two-stage model ages t(DM)(C) of 1543Ma to 1568Ma. It is suggested that the source region of the granite were from argillaceous sedimentary rocks, likely from the Neoproterozoic Shuangqiaoshan Group. We also suspected that the ore-forming metals such as tungsten in the deposit may have likely derived from the Shuangqiaoshan Group. Based on the geochronological framework of the granite, the Yanshanian magmatic activity took place during the transition of the Jurassic and Cretaceous period in an extensional tectonic environment in Jiuling area.
Article
The Dahutang W deposit in Wuning County, Jiangxi Province lies in juncture of Wuning, Jing' an and Xiushui, southwestward 41 km of Wuning County. Dahutang lies in the west part of the east metallogenic belt of Jiangnan uplift in the Lower Yangtze metallogenic province. The Dahutang W deposit is related with Yanshanian granites, and is the largest W deposit recently prospected in China. In this study, we obtain two molybdenite Re-Os ages, one for the Shimensi ore block which shows an isochron age of 143.7 +/- 1.2Ma (n = 6, MSWD = 0. 84); another from the Shiweidong ore block with an isochron age of 140.9 +/- 3.6Ma (n = 6, MSWD =2.30). These ages indicate that the mineralization took place during Early Cretaceous, which are similar to the Cupolymetallic mineralization ages of the Jiurui ore belt on the Lower Yangtze metallogenic province but different to the ages of the South China W metallogenic province. The Lower Yangtze metallogenic province mineralization happened on the two early paleo-continents subduction zones but during the tectonic conversion period. The South China metallogenic province mineralization resulted from the crust remelting granitic magma differentiation and have suffered multiple stages of evolution.
Article
The Pangushan tungsten deposit is a well-known old and large ore deposit which has attracted many researchers and exploration geologists both in China and abroad. In order to determine the ages of magmatism and mineralization in the deposit and thus to gain insights into the relationship between magmatic process and tungsten mineralization, the association of endocontact mineralization with exocontact mineralization as well as their geodynamic setting, the authors conducted LA-ICP-MS zircon U-Pb and ICP-MS molybdenite Re-Os isotopic measurement of Pangushan concealed granite and its endocontact-mineralized quartz veins discovered by 2000 m Nanling Scientific Drilling (SP-NLSD-2). The results indicate that the weighted average ages of zircon 206Pb/238U ages for Pangushan granite and of molybdenite Re-Os isotopic model ages for the quartz veins are (161.7±1.6) Ma and (155.3±2.8) Ma, respectively, both subordinate to Mid-late Jurassic. The determinations, together with previous data, suggest that the mineralized quartz veins were produced by terminal magma evolution, which is supported by the fact that the ages of mineralization and magmatism were basically in accordance, the mineralization all occurred spatially at the inner- and outer-contacts of the granite, and the gradient relationship of granite→feldspar quartz vein→quartz vein was detected in the deposit. Endocontact and exocontact ore-bearing quartz veins were both produced by the same mineralization. Geodynamically, the Pangushan tungsten deposit is one of many important tungsten-polymetallic deposits formed from 165 Ma to 150 Ma associated with large-scale lithospheric extension in South China.
Article
The Taoxikeng tungsten deposit, located in the compounding belt between the eastern segment of the E-W-trending Nanling tectonic zone and the southern segment of the NE-NNE Wuyishan tectonic belt, is an important mining area in the Jiulongnao-Taoxikeng orefield, belonging to a quartz vein-type tungsten polyinetallic deposit consisting predominantly of wolframite. The ore veins cut the Sinian and the tungsten mineralization is mainly controlled by a NW-trending fault. Molybdenite associated with wolframite from quartz ore veins yielded a Re-Os isochron age of 154.4±3.8 Ma and the model age of wolframite is 164.0±2.7 Ma. This suggests that the Taoxikeng deposit formed in the early Yanshaniari and is genetically related to Yanshanian magmatism.
Article
The Dajishan tungsten deposit is in a well - known tungsten ore - forming district in China. Because of technology restriction, little work has been done on the ages of ore - forming and related granite in Dajishan for a long time. By means of the single - zircon U - Pb isotopic method, the intrusion age is reported in this paper, which is 151.7 ± 1.6 Ma for a patched granite body (the source granite for Nb - Ta). And by the quick neutron mobilization method, an 40Ar - 39Ar age of mica from the major ore vein is determined, yielding ore - forming ages of 144 Ma and 147 Ma. Combining these age data with the occurrences of the main granite body, the patched body, the major ore veins and Nb - Ta mineralization, the paper discusses their formation orders and relationships. These data also show that the Dajishan granite and its related mineralizations belong to the result of magmatism in the middle Yanshanian stage and a part of the secondary large - scale mineralization in the Mesozoic.
Article
The Wangxianling intrusion in South Hunan Province consists of two granitoids, the main tourmaline biotite granites and the biotite monzonite granites invading into the former. LA-MC-ICP MS zircon U-Pb dating shows that tourmaline biotite granites formed in Indosinian (235.0 ± 1.3Ma) while the biotite monzonite granites formed in Yanshanian (155.9 ± l.OMa), indicating that Wangxianling intrusion is the product of two-time magmatic activities. The compositions of these two period granites fall into the calc- alkaline category, with an A/CNK ratio of 1.07 ∼ 1.66, which are peraluminous to strongly peraluminous granites. Their whole rock rare earth elements demonstrate total LREE enrichment and HREE deficit with significant negative Eu anomalies (0.01 ∼ 0.38). The ε Hf( t) values and two-staged Hf model ages of tourmaline biotite granites and biotite monzonite granites are -7.92 ∼ +4.61, 1758 ∼ 967Ma and-10.66 ∼-5.35, 1875 ∼ 1538Ma, respectively. In this paper we suggest that both the tourmaline biotite granite and biotite monzonite granite are originated from the Paleo-and Mesoproterozoic crustal remelting, and the earlier tourmaline biotite granites captured a large number of mantle-derived zircons and there were high-ε Hf(t) materials in its source region. Combined with previous research results, we infer that the both Indosinian and Yanshanian periods in South China have tungsten and tin mineralization, the Indosinian granitic magma formed in interval lithosphere extensional environment during the collision compression while the Yanshanian granitic magma formed in the extensional environment of the back arc continental margin.
Article
The Liguifu tungsten - tin polymetallic deposit occurs in the east of Dupangling granite, being mainly of the greisen - quartz vein type. The precise Re - Os isotope dating of molybdenite from the ore shows that the isochron age is (211.9±6.4)Ma (n=7,MSWD=4.1), and the weighted average of model ages is (213.3±2.9) Ma (MSWD=4.0). The isochron age suggests that mineralization took place in the Indo-Chinese epoch, and the result demonstrates that Early - Mesozoic tungsten - tin polymetallic mineralization did happen in Dupangling area.
Article
Huashan-Guposhan intrusive belt is located in the western part of the Nanling Range. It is composed of Niumiao, Tong' an, Huashan, Jinziling, Wuyangshan, Guposhan, etc. granitoid bodies. The U-Pb age dating of 10 samples by SHRIMP, LA-ICP-MS and melting methods reveals that the major phase granitic and dioritic bodies in this belt were emplaced in a narrow time interval of 160∼163Ma. These granitoids are closely related in time, space, material sources, geotectonic setting and genetic mechanism. The synchronous age of Lisong granite and Lisong mafic enclave excludes the possibility of xenolith from country rocks or restite of remelted metamorphic rocks, and provides an important evidence for magma mingling. The later stage Xinlu fine-grained granite with well evolved fractionation characteristics has a zircon U-Pb age of 151Ma, which is about 10Ma later than the major phase granitoids. It probably represents the time duration of fractional crystallization and evolution of the granitic magmatic chamber in this region. The Guiling and Daning granitoid bodies were emplaced in the late Caledonian period.
Article
A study of Re-Os isotopic chronology of molybdenite suggests that the metallogenic age of the Anqiantan tungsten ore deposit in south Jiangxi area within eastern Nanling region is about 156 Ma and that of the Yuanlingzhai molybdenum ore deposit is about 160Ma. Statistics indicate that there occurred 3 epochs comprising 6 stages of mineralization during Mesozoic in the eastern and central parts of the Nanling metallogenic belt. These stages are about 225 Ma and 195 Ma of Indo-Chinese period, 170-160 Ma, 160-150 Ma and 150-145Ma of Early Yanshanian period, and about 135 Ma and 100 Ma of Late Yanshanian period. The mineralization during Early Yanshanian period is the strongest one, so that Early Yanshanian is the major metallogenic period for tungsten and tin ore deposits in the eastern and central parts of the Nanling metallogenic belt. There exist independent W-Sn polymetallic ore deposits, Sn ore deposits, Cu-Pb-Zn polymetallic ore deposits and Mo ore deposits. Combined with an analysis of metallogenic chronology, the authors hold that there might exist undiscovered or neglected mineral resources in the horizontal direction as well as metallogenic potential at the depth of the known ore deposits in the vertical direction. This study has provided theoretic basis for geological prospecting in the second space of the eastern and central parts of the Nanling metallogenic belt.
Article
Chong-Yu-You mineral deposit intensive area is renowned for its wolframite. This paper focuses on the study of 40Ar/39Ar chronology of muscovite from three deposits: Keshuling and Plaotang tungsten-tinmultiple metals deposits (sulphide quartz vein type), and Xian'etang tungsten-tin deposit (quartz vein type) in the Chongyi-Dayu-Shangyou concentrated mineral area. The 40Ar/39Ar plateau age is 158. 8±1. 9 Ma, that of Keshuling is 158. 8±1. 2 Ma for Plaotang, and 231. 4±2. 4 Ma for Xianetang, and the 40Ar/39 Ar reverse isochron ages are 158. 9± 1.4 Ma, 158. 7 ± 1. 9 Ma, and 232. 5±2. 4 Ma respectively. These results indicate that there occurred two metallogenic epochs in the Chong-Yu-You intensive mineral area. Namely, the tungsten-multiple sulfide quartz vein type deposits formed in the Middle Jurassic Epoch mainly between 160 and 150 Ma, similar to the major metallogenic epoch of tungsten-tin deposits in the Nanling region; the cassiterite-scheelite quartz vein type deposits formed in the Indo-Chinese Epoch. The authors also discussed the granite diagenesis and mineralizati n in the Indo-Chinese Epoch and the inherited features of the Mesozoic mineralization in the Nanling area.
Article
Baxiannao is a typical mineralized fractured zone-type W-Sn polymetallic deposit which was discovered recently. Based on detailed petrographic observations and microthermometric studies of fluid inclusion, hydrogen and oxygen isotopes and radiometric dating, this paper studied the origin and evolution of the ore-forming fluid, ages of tungsten mineralization and petrogenesis and tectonic environment of this deposit. The results show that the fluid inclusions are mainly of H 2O-NaCl type with minor CO 2 type. The homogenization temperature peaks of low (150 ∼ \1Q°C , 200 ∼ 220T1 ) , medium ( 250 ∼ 21Q°C ) and high ( 290 ∼ 310T1) indicate multistage fluid activities. The ore-forming fluid is a type of low-salinity, low-density H 2O-CO 2-NaCl system. The δD values of fluids from fluid inclusions in quartz vary from-78%e to -65%e, δ 18:OH 2O values of quartz from the ore change from 4.33%e to 6.44%e, suggesting the ore-forming fluid was derived mainly from magmatic water and was mixed by meteoric water. The dating of zircon from biotite granite determined by SHRIMP yields an age of 157.2 ± 2.2Ma. Re-Os isotopic dating of molybdenite from the Baxiannao fractured zone-type tungsten deposit by ICP-MS yield an isochron age of 157.9 ± 1.5Ma, which is consistent with diagenetic age of biotite granite. Combined with those available from the literature, it can be concluded that tungsten mineralization occurred at the same geodynamic background that is Jurassic intraplate extensional environment during the large-scale extension period of lithosphere in southern China.
Article
The age of tungsten mineralization and petrogenesis of its metallogenetic granitoids, and tectonic environment of the Jiulongnao tungsten orefield in southern Jiangxi Province are studied based on the field investigations and analysis on major-, trace-, and rare earth elements and dating. The Jiulongnao granite is characterized by high silica, alkali, metaluminous to weakly peraluminous, low Ca, Mg, and K2O/Na2O > 1. It also has relatively high LILE (Rb, K), but low LILE (Ba, Sr), and high HFSE (Th, U, Ce, Y, Sm, Nd, Ta, Hf), low HFSE (Nb, P). In addition, Jiulongnao granite shows strong negative Eu anomalies (δEu=0.07-0.10) and high ratios of 10 000Ga/Al (2.76-2.93). Geochemical features of Jiulongnao granite indicate that it belongs to the A-type. The SHRIMP UPb dating of zircon from Jiulongnao granite yields an age of (155.8 ± 1.2) Ma. Re-Os isotopic dating of molybdenite from the Hongshuizhai greisen-type tungsten deposit by ICPMS yields a weighted mean age of (156.3 ± 1.3) Ma, which is consistent with diagenetic age of Jiulongnao granite. Combined with chronological data of Chongyi-Dayu-Shangyou tungsten-tin polymetallic ore concentration area, we conclude that the age of both diagenesis and mineralization of this area are mainly concentrated in 150 to 160 Ma, which is corresponding to the time of the second regional large-scale mineralization in the Mesozoic and these mineralization occurred at the same geodynamic background that is Jurassic intraplate extensional environment during the large-scale extension period of lithosphere.
Article
The Da'ao, tungsten -tin deposit in the Jiuyi Mountains, southern Hunan, is closely related to the Jinjiling composite granite which has the characteristics of aluminous A -type granite. The deposit types include the greisen type, altered granite type, fractured zone alteration type and greisen-quartz vein type. Based on the precise Re-Os dating of molybdenite from the ore-bearing greisen-quartz vein, a mineralization age of 151.3± 2.4 Ma was obtained, which is consistent with the formation age (151-156 Ma) of granite, suggesting that the mineralization occurred simultaneously with the rock formation. An integrated analysis and comparison of highly precise mineralization ages obtained on a regional scale shows that the period of 150-160 Ma was the peak stage of Mesozoic large-scale mineralization in the Nanling region and that the Da'ao tungsten-tin deposit in the Jiuyi Mountains is just the product of this peak stage. The new data provide important isotope chronological evidence for the further study of the regional metallogenic characteristics and guidance of regional mineral prospecting.
Article
The large Huamei'ao tungsten deposit, with total WO3 reserves of 67,400 tons at an average grade of 1.334%WO3, is located in the convergent zone of the eastern Nanling E-W-trending tectono-magmatic belt and the western Wuyishan NNE-SSW-trending tectono-magmatic belt in southern Jiangxi Province, China. The tungsten mineralization in this deposit is mainly found in quartz-wolframite veins, with most orebodies distributed at the outer contact zone between concealed Late Jurassic granitic stocks and Sinian weakly metamorphosed sand-stones and phyllites. Zircons collected from medium- to fine-grained biotite granite in a diamond drill hole at a sea level of ca. -10 m yield a crystallization age of 159.9 (+/- 1.2) Ma through laser ablation-multicollector-inductively coupled plasma-mass spectrometry (LA-MC-ICP-MS) U-Pb dating. Molybdenite and muscovite that were both separated from quartz-wolframite veins yield a Re-Os isochron age of 158.5 (+/- 3.3) Ma and an Ar-40-Ar-39 weighted plateau age of 157.9 (+/- 1.1) Ma, respectively. These dates, obtained via three independent geochronological techniques, constrain the ore-forming age of the Huamei'ao deposit and link the genesis of the ore and the underlying granite. Analyses of available high-precision zircon U-Pb, molybdenite Re-Os and muscovite Ar-40-Ar-39 radiometric ages of major W-Sn deposits in southern Jiangxi Province indicate that there is no significant time interval between W-Sn mineralization and its intimately associated parent granite emplacement (interval of 0-6 Ma). These deposits formed over three intervals during the Mesozoic (240-210, 170-150, and 130-90 Ma), with large-scale W-Sn mineralization occurring mainly between 160 and 150 Ma. The majority of W-Sn deposits in this region are located in southern Jiangxi and southern Hunan provinces.