Ore Geology Reviews最新文献

{"title":"Apatite and zircon compositions as petrogenetic and metallogenic indicators for late Ordovician porphyries in the Songshunangou gold district, North Qilian orogenic belt (China)","authors":"Xuhui Wang ,&nbsp;Weizhe Wu ,&nbsp;Xinghai Lang ,&nbsp;Zuopeng Xiang ,&nbsp;Yulin Deng ,&nbsp;Zifeng Ye ,&nbsp;Weicai Dong ,&nbsp;Chao Luo ,&nbsp;Stephanie Lohmeier ,&nbsp;Hartwig E. Frimmel","doi":"10.1016/j.oregeorev.2025.106502","DOIUrl":"10.1016/j.oregeorev.2025.106502","url":null,"abstract":"<div><div>To elucidate the factors that control Au mineralization in porphyry systems, we present new whole-rock and mineral (apatite, zircon) chemical data on fertile quartz-dioritic porphyries (QDP) and barren granodioritic porphyries (GDP) from the Songshunangou gold district in the North Qilian orogenic belt, China. High Sr/Y ratios and the presence of ubiquitous hornblende phenocrysts, as well as “gull-wing” whole-rock rare earth element (REE) patterns, indicate that magmatic fractionation of hornblende was the main process that accounted for the formation of fertile and barren magma batches. Mineral chemistry of zircon (i.e., Ce/Sm, Yb/Gd, Th/U, and Hf/Y ratios) indicates that the development of the GDP magma was likely controlled by hornblende, apatite, and titanite fractionation, whereas hornblende-dominated fractional crystallization explains the origin of the QDP magma. Application of zircon oxy-barometry yielded moderate oxidation states for both magmas, with ΔFMQ − 0.25 to ΔFMQ + 2.34 (av. ΔFMQ + 0.33) for the GDP, and ΔFMQ − 0.25 to ΔFMQ + 0.72 (av. ΔFMQ + 0.27) for the QDP, which are favorable for the mobilization and transport of Au. Whole-rock and apatite Sr/Y ratios, combined with the (Ce/Nd)/Y and (10000 × Eu/Eu*)/Y ratios of zircon, support that higher H₂O contents were associated with the QDP magma if compared to the GDP. Apatite in the GDP has low <em>X</em>_F/<em>X</em>_Cl ratios of 2.99–11.33, indicating crystallization from a volatile-undersaturated magma, with average melt Cl concentrations of 0.35 wt%. Apatite in the QDP with low <em>X</em>_F/<em>X</em>_Cl ratios (≤7.78) is interpreted to have crystallized from volatile-undersaturated magma with higher melt Cl concentrations (av. 0.42 wt%), whereas apatite with high <em>X</em>_F/<em>X</em>_Cl ratios (11.53–59.80) is interpreted to have crystallized after fluid exsolution. Our results confirm that moderate oxygen fugacity, high H₂O and Cl as well as early fluid exsolution, are prerequisites for porphyry Au mineralization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106502"},"PeriodicalIF":3.2,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143463485","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":"Critical metals Ga and Ge enrichment in the last-stage and low-temperature sphalerite from the Guojiagou Zn-Pb deposit, western Qinling Orogen, NW China","authors":"Lihao Sun ,&nbsp;Xi Chen ,&nbsp;Yi Zheng ,&nbsp;Shixin Zhang ,&nbsp;Fangcheng Pu ,&nbsp;Yihan Wu ,&nbsp;Jiajian Lu ,&nbsp;Kai Ou ,&nbsp;Yan Li ,&nbsp;Pengpeng Yu","doi":"10.1016/j.oregeorev.2025.106494","DOIUrl":"10.1016/j.oregeorev.2025.106494","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Gallium (Ga) and germanium (Ge) have been designated as globally critical metals, driven by their elevating demand and supply risks in high-tech industries such as solar energy, optoelectronics, and green energy. The Xicheng-Fengtai Orefield, situated within the Qinling Orogen of Northwest China, contains over 20 million tons of Zn-Pb metals and thereby is a world-class Zn-Pb orefield hosted in sedimentary rocks. Nevertheless, the potential for Ga and Ge resources in this region has yet to be comprehensively assessed. To investigate this matter further, we selected the representative Guojiagou Zn-Pb deposit to conduct an extensive series of field investigations complemented by micropetrograhic observations and advanced analytical techniques including electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). At the Guojiagou, sulfide mineralization precipitated from brine fluids transporting metals from the basement, resulting in over 3 Mt of Zn-Pb (with 3.34 % Zn and 1.26 % Pb), and was accompanied by extensive ankeritization, silicification, and calcitization. The multifaceted approach enabled us to elucidate mineral paragenesis, sphalerite generations, and their chemical compositions. Our analysis revealed three distinct types of sphalerite: 1) the earliest dark-brown Sp1 intergrown with ankerite; 2) the subsequent brownish-red Sp2 associated with massive pyrite; and 3) the later light-colored Sp3 linked with calcite veins. EPMA and LA-ICP-MS analyses demonstrated that the last crystallized Sp3 exhibits significantly elevated concentrations of Ga (mean = 139.2 ppm) and Ge (mean = 160.9 ppm), surpassing those found in earlier stages: Sp1 (Ga mean = 20.0 ppm; Ge mean = 1.4 ppm) and Sp2 (Ga mean = 31.2 ppm; Ge mean = 4.6 ppm). Binary correlation diagrams for specific elements indicate that Ga integrates into sphalerite’s crystal lattice via Ga&lt;sup&gt;3+&lt;/sup&gt; + Cu&lt;sup&gt;+&lt;/sup&gt; ↔ 2Zn&lt;sup&gt;2+&lt;/sup&gt; while Ge incorporates into its structure through mechanisms such as Ge&lt;sup&gt;4+&lt;/sup&gt; + 2Ag&lt;sup&gt;+&lt;/sup&gt; ↔ 3Zn&lt;sup&gt;2+&lt;/sup&gt; or Ge&lt;sup&gt;2+&lt;/sup&gt; ↔ Cd&lt;sup&gt;2+&lt;/sup&gt; pathways. Furthermore, GGIMFis sphalerite geothermometer results suggest a decreasing trend in ore-forming temperatures from approximately 180–230 °C for earlier forms like Sp1 and Sp2 down to about 120–150 °C for late-stage Sp3. Concurrently, sulfur fugacity values logfS&lt;sub&gt;2&lt;/sub&gt; exhibit a gradual decline from -15 to -10 for both early stages towards -22 to -14 for late-stage Sp3. The widespread occurrence of ankerite combined with low manganese concentrations, mainly ranging from 0 to 20 ppm, supports our assertion that the Guojiagou’s ore fluids were relatively oxidizing—these oxidizing fluids mixing with reduced sulfur generated through thermal reduction of sulfate minerals (TSR), ultimately leading to substantial precipitation of Zn-Pb ores across the site. Our novel findings regarding Ga and Ge concentrations—coupled with reserve es","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106494"},"PeriodicalIF":3.2,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510671","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":"Identification of pegmatite dikes based on remote sensing spectral library and WorldView-3 Data: A Case study in the central Altyn region of Xinjiang","authors":"Chenmeng Li ,&nbsp;Huadong Ma ,&nbsp;Chuan Chen ,&nbsp;Ping Li ,&nbsp;Fang Xia ,&nbsp;Lingling Gao ,&nbsp;Wei Wang ,&nbsp;Xiaofei Du ,&nbsp;Yongqi Hao ,&nbsp;Shunda Li","doi":"10.1016/j.oregeorev.2025.106496","DOIUrl":"10.1016/j.oregeorev.2025.106496","url":null,"abstract":"<div><div>The central Altyn region in Xinjiang is a prospective region for the mineralization of rare metals, such as lithium and beryllium, and is the target area for the exploration of rare metal deposits of the granitic pegmatite type in this study. However, harsh natural conditions complicate the effective identification of pegmatite dikes via conventional techniques, thereby limiting exploration. The narrowness of pegmatite dikes and aeolian sand cover presents challenge, yet remote sensing technology holds significant potential in this area. High spatial resolution data are essential, and a systematic remote sensing identification method has yet to be established. In this study, we established a spectral library of rocks and minerals in the research area and applied image enhancement techniques such as PCA, ICA, MNF, and band ratios to WorldView-3 imagery. By optimizing the display with RGB combinations, 764 pegmatite dikes were successfully identified, and five pegmatite dike group areas were delineated. A “dike-centered limited buffer” method for identifying mineralized pegmatite dikes was proposed. Using measured spectra combined with the spectral angle mapper (SAM) method, lithium-beryllium-bearing dikes were differentiated from non-lithium-beryllium-bearing dikes, and ultimately, 58 lithium-beryllium-bearing pegmatite dikes were identified. Field validation in Areas III, IV, and V indicates that the identification results align well with on-site observations. In this study, we significantly improved the accuracy of pegmatite dike identification in the central Altyn region, providing an effective remote sensing technique and theoretical support for rare metal exploration in this area.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"178 ","pages":"Article 106496"},"PeriodicalIF":3.2,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437967","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":"Controls on metal distributions of the Fengzishan Zn–Pb deposit at the giant Jinding ore field in western Yunnan Province, SW China: Insights from field mapping and 3D geological modeling","authors":"JingKun Liu ,&nbsp;ChuanDong Xue ,&nbsp;Wei Wang ,&nbsp;LiPeng Xue ,&nbsp;Rehana Ghazi","doi":"10.1016/j.oregeorev.2025.106509","DOIUrl":"10.1016/j.oregeorev.2025.106509","url":null,"abstract":"<div><div>The world class Jinding Zn–Pb ore field, located in the Meso–Cenozoic Lanping Basin in western Yunnan Province, SW China, contains significant deposits that are primarily controlled by stratigraphy and structure. However, the migration pathways and driving mechanisms of ore-forming fluids are poorly understood, which limit the minerals exploration. Based on typical orebodies in the Fengzishan Zn–Pb deposit, this study used field mapping and three-dimensional (3D) geological modeling to depict the metal distribution and identify key ore-controlling structures. The results show that lead, zinc, and other base metals are concentrated in the hosting sandstones and breccia limestones of the Upper Triassic Sanhedong Formation. These rocks are located beneath the unconformity with the Miocene Jinding Group and within the hanging walls of NS-trending thrust faults and EW-trending tear faults. Oxidized metal-rich brines from the Jinding Group and reduced H₂S-rich fluids from the Sanhedong Formation migrate along the thrust and tear faults. Elevated Pb, Zn, Cd, and Ag concentrations and low Zn/Pb ratios were observed, suggesting multiple ore-forming fluid recharge events. We propose the following key suggestions: the spatial distributions of metals are controlled by the Jinding Group, the Sanhedong Formation, the unconformity between them, and the thrust and tear faults; the two-source fluids exhibit lateral and vertical flow through fault zones; and this migration is primarily driven by regional EW-trending compressive stresses. Based on regional geological data, the depths and adjacent areas of the Fengzishan and Nanchang deposits were identified as potential exploration targets for mineralization. These insights provide valuable perspectives for understanding the ore-forming processes of Jinding Zn–Pb ore field and similar regions.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106509"},"PeriodicalIF":3.2,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562484","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":"Compositions of in-situ trace elements, S and Pb isotopes of pyrite in Mengqiguer deposit, Yili basin, NW China:implications for uranium mineralization processes of sandstone − type uranium deposit","authors":"Kai Zhao ,&nbsp;Yipeng Zhou ,&nbsp;Kaiyun Chen ,&nbsp;Zhian Bao ,&nbsp;Yan Zhang ,&nbsp;Fang An ,&nbsp;Bailin Wu ,&nbsp;Guangrong Li ,&nbsp;Honglin Yuan","doi":"10.1016/j.oregeorev.2025.106503","DOIUrl":"10.1016/j.oregeorev.2025.106503","url":null,"abstract":"<div><div>Pyrite, a prevalent authigenic mineral in sandstone-type uranium deposits, was examined in the Mengqiguer deposits to elucidate its role in the mineralization process. The investigation utilized polarizing microscopes, scanning electron microscopy (SEM), and Femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry (Fs-La-ICP-MS) to systematically analyze the morphology, genetic sequence in relation to uranium minerals, trace element composition, and sulfur (S) and lead (Pb) isotopic signatures of pyrite. Microscopic observations identified diverse forms of pyrite: pyrite debris (Py1), framboidal pyrite (Py2), fine euhedral pyrite (Py3), and pyrite cement (Py4). Py3 was further categorized into Py3-U (within the ore, in contact with uranium minerals) and Py3-x (in the surrounding rocks, without contact). Py1 predated diagenesis, while Py2 and Py3 formed during the uranium mineralization stage, and Py4 emerged in the late mineralization period. Trace element analysis revealed a decrease in Co, Ni, As, Se, Mo, W, and U contents from Py3-U to Py3-x to Py4. Py3-U, closely linked to uranium mineralization, showed elevated uranium levels and lower δ34S values (−53.99 ‰ to −50.22 ‰), indicative of a biogenic origin. The Co-Ni distribution pattern of Py3-U and Py3-X suggests that the formation of the Mengqiguer deposit may have been influenced by the spontaneous combustion of coal seams, leading to higher formation temperatures. The increased ²⁰⁶Pb/²⁰⁴Pb and ²⁰⁷Pb/²⁰⁴Pb ratios in pyrite are attributed to uranium decay during mineralization, serving as a marker for pyrite formed during this stage. However, the considerable variation in ²⁰⁶Pb/²⁰⁴Pb and ²⁰⁷Pb/²⁰⁴Pb ratios necessitates a comprehensive mineralogical analysis to identify pyrite associated with mineralization using lead isotope ratios. The Mengqiguer uranium minerals are predominantly pitchblende, present as fine pitchblende particles or pitchblende cement. The formation of uranium minerals and pyrite are closely related, with Py3-U being the contemporary mineral of uranium minerals. Specifically, during the uranium pre-enrichment stage, pyrite dissolves and releases Fe³⁺, aiding in the migration and enrichment of uranium (U). In the early mineralization stage, pyrite acts as a reductant, promoting uranium precipitation. During the main mineralization period, significant biological activity reduces Fe³⁺ and U⁶⁺ to form new pyrite (Py2/Py3) and fine pitchblende particles, undergoing multiple dissolution-precipitation cycles. In the superimposition stage of mineralization, pyrite and uraninite transform into cementing materials. Consequently, pyrite and its interaction with uranium minerals together shape the complexity and diversity of uranium mineralization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106503"},"PeriodicalIF":3.2,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552390","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":"Petrology, mineralogy, and geochemistry of major podiform chromite deposits in China: Implications for their genesis","authors":"Qiuyun Yuan ,&nbsp;Huichao Rui ,&nbsp;Rongzhong Bo ,&nbsp;Dongyang Lian ,&nbsp;Pengjie Cai ,&nbsp;Yue Wu ,&nbsp;Osman Parlak ,&nbsp;Haoran Dou ,&nbsp;Haitao Ma ,&nbsp;Ahmed E. Masoud","doi":"10.1016/j.oregeorev.2025.106508","DOIUrl":"10.1016/j.oregeorev.2025.106508","url":null,"abstract":"<div><div>In China, podiform chromite deposits are the primary source of domestic chromite supply. The main chromite deposits are distributed within the Jurassic-early Cretaceous ophiolites of the Yarlung-Zangbo Suture Zone (YZSZ) in Tibet, as well as the Paleozoic ophiolites in Inner Mongolia and Xinjiang. To clarify the metallogenic processes and the associated tectonic settings during the formation of chromite ores in China, this study delves into the petrological, mineralogical, and geochemical characteristics of representative chromitite samples collected from ophiolites in Tibet (Luobusa, Purang, Dongbo, Baer, Cuobuzha, and Dajiweng), Xinjiang (Sartohay), and Inner Mongolia (Hegenshan). Based on the compositions of chromite, these chromitites can be categorized into high-Cr and high-Al types. The mineral inclusions in chromites are mainly composed of silicates, base metal sulfides, and diverse platinum-group minerals (PGMs). PGM inclusions are more frequently detected in high-Cr chromitites compared to high-Al types. Chromitites from the YZSZ ophiolites are predominantly high-Cr types (Cr# 66–82), suggesting their origin from a boninitic melt in a suprasubduction zone (SSZ) environment. The Hegenshan and Sartohay chromitites are typically high-Al types (Cr# 50.5–52.8) and were formed from mid-ocean ridge basalt (MORB)-like magma. By integrating the information of country rocks, we conclude that the major chromite deposits in China are closely associated with distinct magmatism stages in a supra-subduction zone (SSZ) environment, especially during subduction initiation stages. For future chromitite prospecting, we propose that the ophiolitic massifs along the Yarlung-Zangbo suture zone in southern Tibet hold great potential.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106508"},"PeriodicalIF":3.2,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552388","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":"Geochemical and geochronological constraints on the petrogenesis of granitoids from the Ke’eryin area","authors":"Hongzhang Dai ,&nbsp;Xin Li ,&nbsp;Denghong Wang ,&nbsp;Pingyang Gu ,&nbsp;Shanbao Liu ,&nbsp;Genhou Wang","doi":"10.1016/j.oregeorev.2025.106507","DOIUrl":"10.1016/j.oregeorev.2025.106507","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Three granitic plutons with varying degrees of pegmatite development were selected from the Ke’eryin area to investigate the metallogenic characteristics of granitoids related to pegmatite-type rare metal mineralization in the Songpan-Garze Fold Belt (SGFB). Comparative studies, including chronological, geochemical, and isotopic analyses, were conducted on the parental rock (i.e., the Ke’eryin pluton) of lithium-bearing pegmatite in the Ke’eryin lithium ore field, SGFB, China. LA-ICP-MS zircon U-Pb dating revealed crystallization ages of 211.4±1.5 Ma, 209.1±0.9 Ma, and 204.0±1.5 Ma for the Siyuewu (SYW), Nahe (NH), and Elangshan (ELS) plutons, respectively. These findings suggest that all three granitoids were formed in the same tectonic environment as the Ke’eryin pluton. Geochemically, the plutons are enriched in large-ion lithophile elements (LILE) such as Rb, U, and Th, and light rare earth elements (LREE), while showing depletion in high-field-strength elements (HFSE) such as Nb, Ta, and Ti, and heavy rare earth elements (HREE). The plutons also exhibit low A/CNK and Zr + Nb + Ce + Y values, high [La/Yb]N and [Gd/Yb]N ratios, and low concentrations of Cr, Ni, Y, Yb, Sr, P&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt;,and Zr, with a negative correlation between P&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt; and SiO&lt;sub&gt;2&lt;/sub&gt; concentrations. These characteristics indicate that the plutons can be classified as I-type granites, originating from the garnet-plagioclase stability field in the lower crust under granulite facies metamorphic conditions, which contrasts significantly with the Ke’eryin pluton. Zircon εHf(t) and corresponding T&lt;sub&gt;DMc&lt;/sub&gt; values were determined to be −2.77 – −8.15 and 1.42–1.76 Ga for the SYW pluton; 1.81 – −3.26 (with only one spot &gt;0) and 1.13–1.45 Ga for the NH pluton; and −12.81 – 1.62 (with most spots ranging from 0.18 to 1.62) and 1.14–2.05 Ga (with only one spot &gt;1.44 Ga) for the ELS pluton. These results suggest that the three plutons were derived from the partial melting of the Paleoproterozoic to Neoproterozoic crust. The I&lt;sub&gt;Sr&lt;/sub&gt; and εNd(t) values of the ELS pluton samples (I&lt;sub&gt;Sr&lt;/sub&gt; = 0.706688–0.707127, εNd(t) = −3.99 – −5.08, T&lt;sub&gt;DM2&lt;/sub&gt; = 1.31–1.40 Ga)closely correspond to those of the Western Yangtze Block. The SYW pluton samples (I&lt;sub&gt;Sr&lt;/sub&gt; = 0.709392–0.712291, εNd(t) = −6.98 – −9.24, T&lt;sub&gt;DM2&lt;/sub&gt; = 1.56–1.74 Ga) partially overlap with the isotopic range of the Triassic Xikang Group. Meanwhile, the NH pluton samples (I&lt;sub&gt;Sr&lt;/sub&gt; = 0.707948–0.708368, εNd(t) = −6.90 – −7.45, T&lt;sub&gt;DM2&lt;/sub&gt; = 1.55–1.59 Ga) exhibit isotopic values intermediate between those of the ELS and SYW plutons. Importantly, the Sr-Nd-Hf isotopic characteristics are consistent with pegmatite occurrences, suggesting that the assimilation of surrounding Triassic Xikang Group rocks may have contributed to the diverse isotopic compositions and the development of pegmatites. Based on these findings and the regional geological context, ","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106507"},"PeriodicalIF":3.2,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471537","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":"Major and trace element geochemistry of garnets from the Geumseong Mo skarn deposit, South Korea: Genesis and exploration implications","authors":"Ilkyu Kim ,&nbsp;Heonkyung Im ,&nbsp;Dongbok Shin ,&nbsp;Jaeguk Jo","doi":"10.1016/j.oregeorev.2025.106504","DOIUrl":"10.1016/j.oregeorev.2025.106504","url":null,"abstract":"<div><div>Few studies have focused on analyzing the compositional variations of trace elements in garnets from Mo skarn deposits to provide their genetic implication and inform potential applications for both distinguishing skarn types and mineral exploration. To achieve this, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), in conjunction with electron probe microanalysis and sulfur isotope analysis, was employed to the Geumseong Mo skarn deposit located within the Hwanggangri mineralized district of South Korea. The garnets in the skarn were divided into early-formed isotropic dark red (Grt Ia) and light red (Grt Ib) garnets, and later-formed zoned red brown garnets (Grt II). These garnets were found to be replaced by molybdenite and pyrrhotite, respectively. The analysis revealed that Grt Ia and Grt Ib comprise a narrow compositional range, with Gro_50–75Adr_8–34 and Gro_66–89Adr_5–28, respectively. They exhibit positive slopes for light rare earth element (LREE), and variable Eu anomalies and heavy rare earth element (HREE) patterns. On the other hand, Grt II demonstrates a wider range of Gro_3–71Adr_20–96 with increased LREE/HREE ratios compared to Grt Ia and Ib, along with distinct positive Eu anomalies. Moreover, there was a systematic decrease in U concentrations as well as Eu anomalies from the core to the rim in Grt II. The observation suggests that early garnets likely formed under near-neutral pH conditions, while later garnets precipitated under mildly acidic conditions. Sulfur isotope values of sulfides including molybdenite, pyrite, pyrrhotite, and sphalerite give relatively elevated δ³⁴S values, ranging from 10.7 to 13.4 ‰ (avg. 12.4 ‰, n = 10). The sulfur isotope characteristics suggests a significant contribution of sulfur from carbonate host rocks and an isotope disequilibrium under high fluid–rock interactions. The textural and compositional evidence indicates that Grt Ia and Grt Ib were formed under stable conditions through diffusive metasomatism via a fluid system in equilibrium with the host rocks. Conversely, the formation of Grt II appears to have occurred under variable physicochemical conditions with intermittent fluid infiltration. Discrimination diagrams for trace elements demonstrate that the Mo skarn compositional field largely overlaps with the Cu field but is distinct from the W and W-Mo fields. The finding implies that the composition of trace elements in garnet can be utilized to discriminate Mo skarn deposits from other types of skarn mineralization, and thus could be potentially applied to the exploration of Mo skarn deposits.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"178 ","pages":"Article 106504"},"PeriodicalIF":3.2,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445348","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":"Late Jurassic gold mineralization in the North China Craton’s Western belt: S-Pb-H-O isotopic and apatite U-Pb geochronology insights from the Luyuangou gold deposit","authors":"Fanyue Song ,&nbsp;Kadio Aka Donald Koua ,&nbsp;Di Wu ,&nbsp;Guangyong Liu ,&nbsp;Chenglin Yang ,&nbsp;Huashan Sun","doi":"10.1016/j.oregeorev.2025.106501","DOIUrl":"10.1016/j.oregeorev.2025.106501","url":null,"abstract":"<div><div>The North China Craton (NCC) is known for its abundant gold deposits, which occur across two gold metallogenic belts: the western and eastern belts, both trending NNE. Unlike the eastern metallogenic belt, which experienced short-timing early Cretaceous gold mineralization, the western metallogenic belt predominantly features late Jurassic mineralization. However, gold deposits from the late Jurassic are predominantly found in the northern part of the western belt, with fewer occurrences in the southern segment, specifically in the Xiaoqinling-Xiong’ershan gold region. This discrepancy has led to limited research on the late Jurassic gold mineralization in the southern segment, with ongoing debate regarding its occurrence. The Luyuangou gold deposit is a key example in the Xiong’ershan gold district (XESGD), which has long been regarded as a product of early Cretaceous activity due to previous dating accuracy and limitations, thereby limiting the comprehension of its genesis and hindering prospecting endeavors. This paper introduces new geochronological and isotopic (S-Pb-H-O) data for the Luyuangou gold deposit. U-Pb dating of hydrothermal apatite associated with gold-bearing pyrite constrains the mineralization timing to 157.1 ± 6.6 Ma, which fits the Late Jurassic gold mineralization event. The S-Pb-H-O isotope data suggest that the ore-forming materials originated from both the crust and mantle, with ore-forming fluids derived from magmatic and meteoric waters. Collectively, the findings of our study support that the Luyuangou deposit formed in an extensional tectonic environment during Jurassic magmatic activity, which has implications for future prospecting directions in the XESGD.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106501"},"PeriodicalIF":3.2,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143600719","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":"Uncover implicit associations among geochemical elements using machine learning","authors":"Shuguang Zhou ,&nbsp;Zhizhong Cheng ,&nbsp;Jinlin Wang ,&nbsp;Nuo Li ,&nbsp;Guo Jiang","doi":"10.1016/j.oregeorev.2025.106506","DOIUrl":"10.1016/j.oregeorev.2025.106506","url":null,"abstract":"<div><div>The production of geochemical data serves diverse purposes, and a variety of analytical methods are utilized for analyzing geochemical element content. However, due to limitations in project funds, censored or missing values are common in geochemical data. This scarcity of data becomes more pronounced when dealing with large datasets. Regrettably, numerous data analysis techniques are unable to process datasets containing missing values, which presents a significant hurdle for researchers who depend on geochemical data. To address this issue, here we employed a random forest model to simulate the geochemical elements of rocks and stream sediments. By comparing and analyzing the effects of model parameters and feature variable selection on the simulation results of major and trace elements, the study found that with appropriate model parameters and variable selection, the simulation results for many elements are reliable, and the generalization performance of the random forest model is satisfactory. This research sheds light on the inherent correlations among various elements in nature, offers solutions to the challenges posed by missing values in geochemical data, and provides valuable technical support for disciplines such as geology, environmental science and soil science.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"179 ","pages":"Article 106506"},"PeriodicalIF":3.2,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454668","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}