Ore Geology Reviews最新文献

{"title":"Tectonic setting, mineralization, and ore geochemistry of the Paleozoic IOCG deposits in Xinjiang, NW China","authors":"Shuanliang Zhang ,&nbsp;Liandang Zhao ,&nbsp;Pei Liang ,&nbsp;Hongjun Jiang ,&nbsp;Weifeng Zhang","doi":"10.1016/j.oregeorev.2024.106317","DOIUrl":"10.1016/j.oregeorev.2024.106317","url":null,"abstract":"<div><div>The Paleozoic iron oxide copper–gold (IOCG) deposits in Xinjiang correspond to magmatic arc formations (Andean type) within the Central Asian Orogenic Belt (CAOB). These deposits include the Heijianshan, Duotoushan, Shuanglong, and Shaquanzi deposits in the Aqishan-Yamansu belt of Eastern Tianshan, which formed during the inversion of a continental arc-related basin (ca. 310–300 Ma). In contrast, the Laoshankou and Qiaoxiahala deposits along the northern margin of Eastern Junggar formed in an island arc setting (380–370 Ma). Detailed paragenetic studies of these deposits reveal a wide variety of alteration and mineralization patterns, including distinct but typical styles of magnetite and copper–gold mineralization. Fluid inclusion data and isotope tracing of ore-forming fluids indicate the involvement of magmatic-hydrothermal fluids is responsible for the early magnetite mineralization. However, for the late copper–gold mineralization, the deposits formed during the basin inversion have a significant involvement of non-magmatic fluids compared to those of island arc-related deposits. These non-magmatic fluids include basinal brines or residual seawater that reacted with andesitic host rocks. Comparing the IOCG-related magmatic rocks, the regional Bailingshan intrusive complex in the Eastern Tianshan formed during the basin inversion is from more reduced and water-poor parental magma compared to arc magma in the Eastern Junggar. However, the tectonic setting (basin inversion) facilitated the migration and involvement of external fluids, including sulfur, in the mineralization process, potentially compensating for the deficiencies of the magma to generate late economic copper–gold mineralization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"175 ","pages":"Article 106317"},"PeriodicalIF":3.2,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation of the intrusion-hosted orogenic-type gold lodes: Exemplified by the Axile gold deposit in the Chinese Altai","authors":"Abulimiti Aibai ,&nbsp;Xiaohua Deng ,&nbsp;M. Santosh ,&nbsp;Nuo Li ,&nbsp;Xi Chen ,&nbsp;Yongxiang Wang ,&nbsp;Yanjing Chen ,&nbsp;Wenjiao Xiao","doi":"10.1016/j.oregeorev.2024.106336","DOIUrl":"10.1016/j.oregeorev.2024.106336","url":null,"abstract":"<div><div>Unlike the gold deposits typically hosted in metamorphosed volcanic-sedimentary sequences, the recently discovered Axile gold deposit (over 13 t Au at 5.35 g/t) is a unique example in the Chinese Altai for evaluating the genesis of intrusion-hosted lode gold deposits in metamorphic terranes. The orebodies in this deposit occur as quartz veins and altered tectonites hosted in the sinistrally sheared quartz diorite and biotite granite zones in the Habahe intrusion. The quartz vein-type ores are composed of quartz-pyrite veins and quartz-polymetallic sulfide veins, in which gold-tellurides also occur. The altered tectonites, spatially associated with the quartz veins, are composed of deformed and altered rocks of quartz diorite and biotite granite. Main alterations include quartz, sericite, calcite, chlorite, albite, pyrite, chalcopyrite, and gold-tellurides. Two types of fluid inclusions are identified in the ores, i.e., (1) carbonic-aqueous (C-type) and (2) aqueous (W-type), with the C-type being dominated. These fluid inclusions yield salinity ranging from 3.6 to 9.0 wt% NaCl equivalent and homogenization temperatures in the range of 249 − 387 ℃, suggesting a typical mesothermal NaCl-CO₂-H₂O system. The Axile deposit thus corresponds to an orogenic-type gold deposit.</div><div>The hydrothermal titanites in the auriferous quartz-pyrite veins yield <em>in situ</em> U-Pb ages around 278.4 ± 2.4 Ma (MSWD = 3.1, 2σ), which constrain the gold mineralization timing as Permian. The mineralized quartz diorite and biotite granite yield zircon U-Pb ages of 377.0 ± 1.0 Ma (MSWD = 0.1; 1σ) and 394.0 ± 1.2 Ma (MSWD = 0.4; 1σ), respectively, which show that the ore-hosting intrusions were emplaced in the Devonian, obviously earlier than the gold mineralization. The light δ¹³C_V-PDB values (−15.5 ‰ to −6.7 ‰, average −10.7 ‰) of the CO₂ extracted from the fluid inclusions display a significant contribution from the organic carbon in sediments. Given the sedimentary rocks underwent Permian greenschist to amphibolite facies metamorphism in the Chinese Altai, accompanied by the synchronous structural deformation and shearing activities, it could be concluded that the Axile gold deposit is formed by a shear zone-controlled mesothermal system that originated from metamorphic-devolatilization. The Chinese Altai Orogen is an orogenic-type gold metallogenic belt, containing both the intrusion- and metamorphic rock-hosted gold deposits, illustrated by a consistent genetic model.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"175 ","pages":"Article 106336"},"PeriodicalIF":3.2,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-stage REE mineralization in the Bayan Obo Fe-REE-Nb deposit: Constraints from biotite and apatite geochemistry","authors":"Pei Liang ,&nbsp;Junyi Wang ,&nbsp;Bicheng Li ,&nbsp;Yuling Xie ,&nbsp;Jinsheng Han ,&nbsp;Jiaming Xia ,&nbsp;Bingbing Li ,&nbsp;Li Chen","doi":"10.1016/j.oregeorev.2024.106312","DOIUrl":"10.1016/j.oregeorev.2024.106312","url":null,"abstract":"<div><div>This new discovery of the silicate-calcite complex pluton for the Bayan Obo Formation in the giant Bayan Obo deposit, North China craton, with varied petrographic characteristics of biotite-, calcite-biotite-, calcite- and carbonatite units, from outer to inner, provides a new direction for us to explore the enrichment mechanism of REE mineralization in carbonatite and subsequent post-carbonatite hydrothermal fluid. As the sensibility to chemical and physical factors associated with magmatic crystallization fractionation and fluid activities, biotite and apatite from the Bayan Obo deposit were taken detailed petrographic, geochronologic and geochemical compositional study. Two groups of biotite and apatite have been divided, including primary magma-related ones with age of 1231 Ma, which is characterized by relatively high K/Rb ratios and temperature; and altered hydrothermal ones with ages of 280 to 240 Ma, which is characterized by relatively high X_Mg, Al^IV, F, REE contents, high oxygen fugacity, and low temperature. Significantly discrepant geochemical characteristics of types of biotite and apatite indicate disparate REE mineralization in magmatic and hydrothermal processes. For the magmatic process, the crystallization of REE-poor minerals during the evolution of silicate-carbonatite complex results in the enrichment of REE and the differentiation between HREE and LREE in the residual carbonatite magma. For the hydrothermal process, the highest REE contents in altered hydrothermal biotites and apatites formed by REE/F-rich late hydrothermal fluids, which was supposed to source from the Hercynian magmatic activities. In addition, the high contents of F in late hydrothermal biotites and apatites are assumed to be important for the enrichment and precipitate of REE minerals.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106312"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence and enrichment of critical metals in ferromanganese deposits in the western Pacific","authors":"Xianze Deng,&nbsp;Jiangbo Ren,&nbsp;Xiguang Deng,&nbsp;Jun Tu,&nbsp;Shuang Hong,&nbsp;Gaowen He,&nbsp;Limin Zhang,&nbsp;Yong Yang","doi":"10.1016/j.oregeorev.2024.106314","DOIUrl":"10.1016/j.oregeorev.2024.106314","url":null,"abstract":"<div><div>Co-rich ferromanganese nodules and crusts are economically valuable deep-sea ferromanganese deposits widely distributed in the western Pacific Ocean and are rich in critical metals such as Co, Ni, Cu and rare earth elements (REEs). However, the lack of fine delineation and systematic comparisons of the distributions of these critical metals in these ferromanganese deposits limits the understanding of the occurrence states of Co, Ni, Cu and REEs and the metallogenesis of ferromanganese deposits. Therefore, the authors selected one nodule and one crust from the western Pacific Ocean, and utilized high-resolution methods such as micro-area X-ray fluorescence spectrometry (μ-XRF), laser-ablation inductively-coupled plasma time-of-flight mass spectrometry (LA-ICP-TOF-MS), and laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) to depict elemental distribution and elemental profile.</div><div>The results show that the ferromanganese deposits are predominantly composed of Fe-vernadite with low Mn/Fe ratios. Co, Ni and Cu exist primarily in the manganate octahedral layer of Fe-vernadite. REEs mostly exist in feroxyhite of Fe-vernadite, and manganate octahedral layer of Fe-vernadite also have high Ce content. Co, Ni and Cu contents of ferromanganese deposits are closely correlated with Mn/Fe ratios: Co, Ni and Cu contents increase with Mn/Fe ratios until the Mn/Fe ratios rises up to 4, and remain stable when Mn/Fe ratios &gt; 6. The enrichment of Co, Ni and Cu in ferromanganese deposits is controlled by the redox conditions of seawater during accretion, whereas REEs enrichment is related to Mn and Fe fluxes in seawater during accretion. The coupling relationships between elemental distributions help to reveal the elemental occurrence state, and the geochemistry of ferromanganese deposits are analyzed to identify element enrichment mechanism.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106314"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The formation and recycling of Neoproterozoic granitoids in the Jiangnan Orogen, South China: Implications for Mesozoic rare metal mineralization","authors":"Hongfei Di ,&nbsp;Yong-Jun Shao ,&nbsp;Yi-Qu Xiong ,&nbsp;Matthew J. Brzozowski ,&nbsp;Di Wang ,&nbsp;Lei Liu ,&nbsp;Zhi-Wei Fan ,&nbsp;Wenjie Fang","doi":"10.1016/j.oregeorev.2024.106332","DOIUrl":"10.1016/j.oregeorev.2024.106332","url":null,"abstract":"<div><div>In the era of energy transition on the Earth, rare metal mineralization has attained increased significance for various energy sectors and understanding their formation and evolution in various tectonic settings is of great importance for formulating exploration strategies. The Neoproterozoic Jiangnan Orogen in South China marks the assembly zone of the Yangtze and Cathaysia blocks and carries numerous rare metal deposits. In this contribution, we investigate the Neoproterozoic Jiuling composite batholith to understand the formation of rare metal mineralization. We present new in-situ zircon U–Pb ages and Lu–Hf isotopes, and whole-rock geochemistry and Sm–Nd isotopes of the Banbei biotite granodiorite and the associated rare metal-mineralized Baishawo granites in the western portion of the Jiuling batholith suite. Zircon U–Pb dating indicates that the Banbei biotite granodiorite, and the Baishawo two-mica granite and muscovite granite formed at ca. 820 Ma, 153 Ma, and 142 Ma, respectively. The ε_Hf(t) values of the biotite granodiorite, two-mica granite and muscovite granite are –4.4 to +5.8, –11.8 to –7.0, and –10.5 to –7.3, respectively. The ε_Nd(t) values of the biotite granodiorite, two-mica granite and muscovite granite are –3.88 to –2.73, –10.6 to –10.2, and –9.23 to –9.16, respectively. Zircon Hf isotopes and whole-rock Sm–Nd isotopes suggest that the granite suite was sourced from the Mesoproterozoic crust. Geochemical modeling suggests that the Banbei biotite granodiorite was derived from partial melting of Meso- to Neoproterozoic metasedimentary rocks, whereas the Baishawo two-mica granite and muscovite granite were derived from assimilation–fractional crystallization of the Neoproterozoic Banbei biotite granodiorite and Mesozoic magma with low degrees of differentiation. Combined with previous studies on the granite suites in the Jiangnan Orogen, we suggest that collision between the Yangtze and Cathaysia blocks ceased at least 820 Ma, and that Precambrian rocks might have contributed significantly to the enrichment of rare metal mineralization in Mesozoic granite through reworking.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106332"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralization of Zn-Pb-Ag and associated critical metals: An introduction","authors":"Jia-Xi Zhou ,&nbsp;Yi Zheng ,&nbsp;Yan-Jun Li ,&nbsp;Thomas Ulrich ,&nbsp;Ling-Li Zhou","doi":"10.1016/j.oregeorev.2024.106328","DOIUrl":"10.1016/j.oregeorev.2024.106328","url":null,"abstract":"<div><div>The combination of zinc (Zn), lead (Pb), and/or silver (Ag) is widely developed in various types of deposits. They also form various types of independent deposits and are associated with a variety of critical metals, such as germanium (Ge), cadmium (Cd), gallium (Ga), and thallium (Tl). The Zn-Pb-Ag deposits make an important group of mineral deposits worldwide, including volcanic-hosted massive sulfide (VHMS), magmatic-hydrothermal-associated skarn and/or epithermal, sedimentary rocks-hosted (e.g., Sedimentary Exhalative, SEDEX; carbonate-hosted epigenetic/Mississippi-Valley-type, MVT; Sandstone/shale-hosted epigenetic, SST), and hydrothermal-vein types. This Special Issue aims to provide a comprehensive understanding of Zn-Pb-Ag deposits and associated critical metals in a variety of geological settings, and promote global prospecting. This Special Issue contains 61 papers (including reviews) covering major Zn-Pb-Ag metallogenic provinces/zones worldwide. The publications provide a comprehensive and systematic analysis including ore deposit geology, geochemistry, geochronology, ore-forming dynamics process and background, big data and deep learning, metallogenic prognosis and ore genesis of Zn-Pb-Ag deposits, as well as the occurrence status and enrichment mechanisms of associated critical metals. These achievements will help to establish more practical mineralization and prospecting models. Equally, they promote the understanding of the genesis of Zn-Pb-Ag deposits, develop new mineralization theory for Zn-Pb-Ag deposits, and provide a theoretical basis for the comprehensive utilization of associated critical metals.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106328"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"K, Sr isotopes, and trace element to constrain potash origin in the Simao Basin, southwestern China, and insight into K isotope geochemical behavior in evaporite","authors":"Zhong-Ying Miao ,&nbsp;Mian-Ping Zheng ,&nbsp;Peng-Cheng Lou ,&nbsp;Zhi-Guang Xia ,&nbsp;Wei-Qiang Li ,&nbsp;Lin-Feng Shi ,&nbsp;Gao Song ,&nbsp;Xue-Fei Zhang ,&nbsp;Yuan-Ying Liu","doi":"10.1016/j.oregeorev.2024.106322","DOIUrl":"10.1016/j.oregeorev.2024.106322","url":null,"abstract":"<div><div>With the advancement of emerging potassium isotope testing techniques, the characteristics of <em>δ</em>⁴¹K in evaporite have garnered increasing attention. Its application in constraining the genesis of potash deposits and tracing the process of potash mineralization holds significant prospects. A comprehensive analysis of the geochemical characteristics of K, Sr isotopes, and trace elements provides an opportunity to address the ongoing debate regarding the mineralization mechanism of potash in the Simao Basin. In this study, we collected 64 potash samples from the Simao and Khorat basins. The analytical results revealed that the major ions in the samples consist of Na⁺, K⁺, Mg²⁺, Ca²⁺, Cl⁻, and SO₄^2-, while the trace elements Br, Sr, Rb, B, Li, V, Cr, Mn, Ba, As, and Zn are relatively enriched. The <em>δ</em>⁴¹K values range from −0.12 ‰ to 0.20 ‰ with an average of 0.01 ‰. The ⁸⁷Sr/⁸⁶Sr ratios range from 0.707553 to 0.708565 with an average of 0.708020, which is lower than that of the river water in the drainage basin. Additionally, the Br content ranges from 316.3 × 10⁻⁶ to 1709.1 × 10⁻⁶, with an average of 633.8 × 10⁻⁶. These data indicate that the Early Cretaceous Albian-Middle Jurassic Bajocian seawater serves as an important source of potassium for potash deposition in the Simao Basin. The characteristics of the ratios of the Br/Cl (mmol/mol), K/Cl (mmol/mol), Rb/Sr (mol/mol), along with the contents of the Br and Rb, indicate that the most of potash in the Simao Basin is primary origin. Moreover, we have also provided new insight into the geochemical behaviors of K isotopes during the evolution of the evaporites. The precipitation of potash may be accompanied by K isotope fractionation, as evidenced by the lighter K isotope composition of carnallite compared to that of sylvinite. K isotope fractionation occurs between the secondary sylvite and its parent source, and newly precipitated solids are characterized by relatively light K isotope. Episodic freshwater inflow into the evaporative basin stimulates microbial activity, leading to fluctuations in K isotopes in the precipitated potash during the same evaporation stage. Therefore, this work not only provided direct evidence from the K isotopes for determining the origin of the potash in the Simao Basin but also further perceived the geochemical behaviors of K isotopes during the evolution of evaporite.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106322"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochronological and geochemical constraints on the multistage magmatic processes of the Lianhuashan batholith, South China: Implications for the petrogenesis and polymetallic mineralization","authors":"Jinhua Qin ,&nbsp;Denghong Wang ,&nbsp;Fan Huang ,&nbsp;Shihua Zhong","doi":"10.1016/j.oregeorev.2024.106327","DOIUrl":"10.1016/j.oregeorev.2024.106327","url":null,"abstract":"<div><div>The Lianhuashan batholith, which is a composite pluton located in the middle part of a world-class giant tungsten (W) polymetallic belt of South China, hosts a huge reserve of more than 50,000 t of W. Despite this great economic significance, the petrogenesis of each phase of the Lianhuashan batholith, as well as its temporal and genetic relationships to the W polymetallic mineralization, is still unclear. To address these questions, we conducted a comprehensive study for the Lianhuashan batholith, including LA-ICP-MS zircon U-Pb dating, whole-rock geochemical and in-situ mineral trace element analyses. Different from previous studies, four main granitic phases (G1–G4) were identified. The biotite granite (G1) formed from 168.6 to 165.3 Ma, has the lowest Si content and high Al and Fe contents, and is significantly depleted in Ba, Sr, Ti, P, and Nb whereas enriched in U, Hf, Zr, and Y contents. In contrast, the two-mica granite (G2) and fine-grained muscovite granite (G3), which formed from 162.8 to 160.5 Ma, exhibit similar characteristics including enrichment in La, Y, Hf, Th, U, and depletion in Ba, Sr, and P. The porphyritic granite (G4) is the latest magmatic phase and formed at 158.3 Ma. It is characterized by high K, Si, Th, U, Zr, Hf contents but low Al_, Fe, Sr, P, and Ti contents. These features support that four main phases of the Lianhuashan batholith belong to S-type granites that experienced significant fractional crystallization, and display reduced and low temperature features. Combined with previously published studies, we suggest that the Lianhuashan batholith formed in an intraplate extensional setting triggered by the high-angle rollback subduction of the paleo-Pacific plate. The three early phases (i.e., G1–G3) are in turn more oxidized and are responsible for the transition from Sn- to W-dominated mineralization. In contrast, the G4 granite, characterized by lower oxygen fugacity, is resposible for Pb-Zn-Ag-U polymetallic mineralization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106327"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trace element of epidote from the Tonglushan Cu-Fe-Au deposit, eastern China: Implications for exploration indicator for skarn mineralization","authors":"Qiaoqiao Zhu ,&nbsp;Guiqing Xie ,&nbsp;Lifan Lu ,&nbsp;Fang Yan ,&nbsp;Heng'an Cai","doi":"10.1016/j.oregeorev.2024.106298","DOIUrl":"10.1016/j.oregeorev.2024.106298","url":null,"abstract":"<div><div>Epidote is a common alteration phase in magmatic-hydrothermal deposits. It has been widely used as an indicator for vectoring mineralization centers and fertility assessments for porphyry ore deposits. However, whether epidote from skarn deposit without significant porphyry-style mineralization can also serve as an exploration indicator remains unclear. Major and trace elements of epidote from the quartz monzodiorite (porphyry) (QMD), endoskarn, Cu-Fe ore, and exoskarn/marble at Tonglushan were analyzed by electron microprobe analysis (EMPA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to constrain their variations across the deposit. The EMPA results suggest that the major compositions (e.g., Al, Fe, and Mn) of epidote are more likely to be affected by precursor minerals such as plagioclase, garnet, diopside, and features of fluid composition (e.g., <em>f</em>O₂, temperature, and Fe³⁺ abundance). Epidote trace elements, however, may controlled by coprecipitating minerals such as sulfides and magnetite, which may strongly enrich in certain elements (e.g., As, Sb, Co, Ti, and V) relative to the epidote, as well as precursor allanite which has significantly elevated trace elements (such as As and V) than the successor epidote replacement. The contents of Na, Mg, Mn, Co, and Sn in epidote show a general increase from QMD, through endoskarn, to Cu-Fe ore and then decreasing to exoskarn/marble whereas that of Sc, V, Y, Zr, Sb, and total REE show an opposite trend. The general patterns of these trace elements in skarn epidote may potentially indicate the direction of orebodies. The strong-moderate linear correlation (R² = 0.76 to 0.93) of As and Sb contents in epidote with the tonnage of Cu or distance from the magmatic-hydrothermal center demonstrates their potential as a quantitative evaluation tool. In general, the trace element contents of skarn epidote are expected to provide critical information for skarn deposit exploration.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106298"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrological, mineralogical, carbonate C-O and sulfide S isotope study of the Bayinqinggeli sandstone-hosted uranium deposit in the northern Ordos Basin","authors":"Xiaowen Hu ,&nbsp;Mingxing Ling ,&nbsp;Jianbing Xu ,&nbsp;Qing Gong ,&nbsp;Xiaoyong Yang ,&nbsp;Huaming Li ,&nbsp;Chao Lu ,&nbsp;Zhencheng Li ,&nbsp;Longhui Wang ,&nbsp;Zhiyong Ren ,&nbsp;Tao Guo ,&nbsp;Yujie Hu ,&nbsp;Gaofeng Du ,&nbsp;Wei Xie ,&nbsp;Yijun Feng","doi":"10.1016/j.oregeorev.2024.106334","DOIUrl":"10.1016/j.oregeorev.2024.106334","url":null,"abstract":"<div><div>Many sandstone-hosted uranium deposits have been discovered in the northern Ordos Basin, including the Bayinqinggeli deposit, exhibiting tremendous potential for uranium exploration and prospecting. This region is characterized by complex fluid activities, yet unknowns or controversies still exist regarding the source and properties of the fluids and their influence on uranium mineralization. In this study, we employed optical and scanning electron microscopy (SEM), X-ray diffraction (XRD), micro X-ray fluorescence (μ-XRF), C-O isotope of calcite, and <em>in situ</em> S isotope of pyrite, to investigate the genesis and evolution of the Bayinqinggeli deposit. Pyrite and calcite are closely associated with uranium minerals, and all exhibit distinct characteristics in rocks of varying grades. In high-grade mineralized rocks, ore-related pyrite, characterized by euhedral and colloidal forms, mainly predated uranium mineralization, evidenced by the extensive coffinite replacement. The mostly negative δ³⁴S values with a broad range (−24.6 ‰ to 23.9 ‰; mean = −4.2 ‰) point to microbial sulfate reduction under restricted conditions. In low-grade and barren rocks, pyrite unrelated to mineralization, mainly as large granular or colloidal cement, shows generally positive δ³⁴S values with a wide range (−49.5 ‰ to 67.4 ‰; mean = 15.3 ‰). This suggests the involvement of both biological and abiological processes during different stages, with the latter possibly associated with deep-sourced fluids. Considering the heterogeneous isotope compositions of sulfur in pyrite and carbon in calcite (δ¹³C ranging from −21.4 ‰ to −4.9 ‰), it can be deduced that the deposit was strongly affected by two types of fluids: (1) surface oxidizing fluids and (2) deep reducing fluids. The mineralizing fluids were derived from oxidizing surface water, which dissolved uranium ions, carbonates, and sulfates from weathered source rocks and during infiltration through the sandstone, resulting in the formation of abundant uranium minerals and associated pyrite and calcite. The presence of low δ¹³C calcite further corroborates the influence of deep hydrocarbon-bearing fluids, which played a protective role in post-ore stage preservation, corresponding to the widespread green alteration in the Lower Zhiluo formation. Overall, the development of sandstone-hosted uranium deposits is a continuous and progressive process, with early-formed mineralization being transformed by late-stage fluid events. Calcite has a significant impact on the formation, development, and extraction of uranium ores in the deposit, protecting the paleo-orebodies against remobilization and remigration. A significant portion of uranium ore is preserved by calcite cementation. Therefore, the careful management of carbonates during <em>in situ</em> leaching is essential for the effective extraction of uranium from the host sandstones.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"174 ","pages":"Article 106334"},"PeriodicalIF":3.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142651228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}