Ore Geology Reviews最新文献

{"title":"Mafic mineral chemistry as an insight into magma characteristics, tectonic settings and mineralization in three magmatic Ni-Cu deposits in North Xinjiang, NW China","authors":"Shuai Wei ,&nbsp;Zhong-Jie Bai ,&nbsp;Xie-Yan Song ,&nbsp;Yu-Feng Deng ,&nbsp;Wei-Guang Zhu ,&nbsp;Wen-Bin Ji ,&nbsp;Meng Yuan","doi":"10.1016/j.oregeorev.2025.106887","DOIUrl":"10.1016/j.oregeorev.2025.106887","url":null,"abstract":"<div><div>This study utilizes detailed mineral chemistry of mafic phases (clinopyroxene, hornblende, olivine, Cr-spinel) from the Huangshandong (HSD), Huangshanxi (HSX), and Kalatongke Ni-Cu sulfide deposits in the Central Asian Orogenic Belt to elucidate magma characteristics, tectonic settings, and key factors of mineralization. Crystallization conditions (1174–1234 °C; &lt;400 MPa) suggest rapid magma emplacement and imply that regional strike-slip structures facilitated efficient magma ascent and promoted mineralization. The primary magmas were high-Mg tholeiitic melts with moderate H₂O contents (&lt;2.6 wt%), as indicated by: equilibrium melt compositions constrained by Cr-spinel chemistry; trace-element ratios in hornblende (e.g., Sr/Hf&lt;200); and clinopyroxene hygrometry combined with compositional discrimination. Cr-spinel compositions (Cr#=41–64) and clinopyroxene chemical trends (rift-cumulate) reflect a non-arc, post-subduction extensional setting associated with asthenosphere upwelling triggered by slab detachment. The melts in equilibrium with orthopyroxene exhibit LREE enrichment signatures, indicating derivation from subduction-metasomatized lithosphere mantle. The enrichment of U and Pb in the melt equilibrium with hornblende confirms the incorporation of crustal material into the magma source, consistent with metasomatized mantle characteristics. The magma source comprises upwelling asthenosphere mantle and metasomatized mantle. Lower Ce/Pb ratios in the melts relative to arc and back-arc lavas suggest upper crustal contamination. Crustal contamination plays a key role in sulfide saturation.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106887"},"PeriodicalIF":3.6,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The newly discovered Li-Rb-Cs mineralization at the Bu Me Sn-W greisen deposit within the Truong Son orogenic belt in Vietnam","authors":"Tuan Anh Tran ,&nbsp;Peter A. Nevolko ,&nbsp;Hoang Ly Vu ,&nbsp;Tatyana V. Svetlitskaya ,&nbsp;Tuan Anh Nguyen ,&nbsp;Trong Hoa Tran ,&nbsp;Ngoc Can Pham ,&nbsp;Thi Huong Ngo ,&nbsp;Thi Phuong Ngo ,&nbsp;Quoc Cong Tran ,&nbsp;Thi Phuong Lien Pham ,&nbsp;Duc Luong Le","doi":"10.1016/j.oregeorev.2025.106879","DOIUrl":"10.1016/j.oregeorev.2025.106879","url":null,"abstract":"<div><div>The Truong Son Orogenic Belt (TSOB) is one of the most significant orogenic belts within the Indochina block. The Bu Me deposit is located within this belt and has historically been significant for the mining of Sn-W metals. Recently, newly discovered metal assemblages at the Bu Me Sn-W deposit has also shown significant lithium–rubidium–cesium (Li-Rb-Cs) mineralization. To constrain the timing and petrogenesis of the magma and Sn-W-Li-Cs-Rb mineralized, a systematic study involving U–Pb ages dating, as well as whole-rock and minerals chemical analyses, was conducted for the Bu Me deposit. U-Pb zircon geochronology of biotite granite, leucogranite, and granite porphyry indicates that these rocks were emplaced at 29.3 ± 0.2 Ma, 29.2 ± 0.4 Ma, and 28.6 ± 0.3 Ma, respectively. The granites exhibit moderate to high SiO₂ content (71.91––74.08 wt%), high total alkali, and a peraluminous signature, classifying them as A2-type granites. Leucogranites and granite porphyries are notably enriched in lithium, with concentrations reaching up to 1400 ppm. Based on detailed observations and characterization of textures and mineral assemblages, three principal mineralization stages have been identified: (1) Early Li-Rb-Ca ± Nb quartz-topaz-mica stage, (2) Sn-W ± sulfides quartz-topaz greisen stage, and (3) Quartz vein stage. Detailed EPMA analyses of minerals from these stages suggest that Li-Rb-Cs-Sn-W mineralization is primarily hosted in minerals such as siderophyllite, protolithionite, cassiterite, and wolframite. These findings demonstrate the significant economic potential of rare metal (Li-Rb-Cs-Sn-W) mineralization in the Truong Son Orogenic Belt.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106879"},"PeriodicalIF":3.6,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145060396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linking paleoproductivity to REE-rich mud formation: geochemical evidence from the Clarion-Clipperton Fracture Zone in the pacific","authors":"Bo Xiang ,&nbsp;Xibin Han ,&nbsp;Yanhui Dong ,&nbsp;Zhongsheng Xu ,&nbsp;Yanyan Zhao ,&nbsp;Guangyao Cao ,&nbsp;Zhentao Hu ,&nbsp;Xiaohu Li","doi":"10.1016/j.oregeorev.2025.106877","DOIUrl":"10.1016/j.oregeorev.2025.106877","url":null,"abstract":"<div><div>Deep-sea sediments enriched in rare earth elements, termed “REE-rich mud,” represent a promising resource with substantial economic potential. Nevertheless, the role of paleoproductivity in their formation remains poorly understood. In this study, we focus on the geochemical characteristics of two adjacent sediment cores (GC02 and GC03) from the Clarion-Clipperton Fracture Zone (CCFZ) in the Pacific. Compared to core GC03 with an average concentration of lanthanoids and yttrium (ΣREY) of 477 ppm, the REE-rich muds in GC02 show a significantly higher average ΣREY of 843 ppm, coupled with lower δ¹³C_TOC and δ¹⁵N values. Additionally, the REE-rich muds contain elevated concentrations of bio-SiO₂ and excess Ba. These geochemical features suggest markedly enhanced paleoproductivity during the deposition of the REE-rich muds. The significantly lower δ¹⁵N values in GC02 (averaging 5.9 ‰ vs. 9.9 ‰ in GC03) indicate that rapid expansion of oxygen minimum zones (OMZs) was triggered by high productivity, which intensified water-column denitrification and depleted the regional nitrogen inventory during the Oligocene. To compensate for nitrogen loss, significantly enhanced nitrogen fixation occurred, sustaining persistently high productivity levels. Crucially, the expansion of OMZs reduced the degradation of organic matter in the mesopelagic zone, thereby increasing its export flux to the seafloor. During intense early diagenesis, decomposition of this organic matter at the sediment–water interface released REE, which were subsequently incorporated into abundant biogenic apatite formed under high productivity.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106877"},"PeriodicalIF":3.6,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The occurrence and distribution of thorium in the giant Bayan Obo REE-Nb-Fe polymetallic deposit, China","authors":"Hai-Dong She ,&nbsp;Hong-Rui Fan ,&nbsp;Biao Chen ,&nbsp;Kui-Feng Yang ,&nbsp;Xiao-Chun Li ,&nbsp;Qi-Wei Wang","doi":"10.1016/j.oregeorev.2025.106883","DOIUrl":"10.1016/j.oregeorev.2025.106883","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Thorium (Th) is increasingly regarded as a critical element for next-generation nuclear energy systems due to its status as the most abundant fissile material on Earth and its advantageous safety properties. The Bayan Obo deposit in Inner Mongolia (China), contains the largest known reserves of rare earth elements (REE) globally, along with significant amounts of niobium (Nb), iron (Fe), and Th. Despite the considerable Th resources within this deposit, the spatial distribution, occurrence state, and genetic relationship with the REE-Nb-Fe mineralized systems are still poorly understood.&lt;/div&gt;&lt;div&gt;In this study, Th distribution and the intrinsic relationship with REE-Nb-Fe mineralization were investigated by a systematic mineral-geochemical composition analysis (XRF, TIMA, and EPMA) of various rocks and ores in the Bayan Obo deposit. Spatially, Th concentrates along the contact zone (fluorite-rich banded/massive ores) between ore-hosting dolomite and K-rich slate, with four high-Th zones (&gt;200 ppm) in the Main and East open pits. The abundance of Th in ores and rocks exhibits considerable variability, ranging from 1.1 to 587 ppm. This significant heterogeneity in the distribution of Th within the deposit is primarily attributed to Th migration induced by late thermal events, thereby creating scattered Th-Pb ages in the REE minerals. Chemical and mineralogical mapping indicates that Th in the Bayan Obo deposit is primarily hosted in REE minerals, Nb-bearing minerals and thorite. Although Nb-bearing minerals exhibit higher Th concentrations (e.g., aeschynite: 4.1 wt% ThO&lt;sub&gt;2&lt;/sub&gt;), REE minerals (e.g., monazite and fluorocarbonate) dominate Th resource volume due to their extensive distribution. Among these REE minerals, monazite in the disseminated, banded and vein ores of the West Open Pit displays the highest Th content (median &gt;1 wt%). Additionally, the biotite-altered disseminated ore in the Main Open Pit contains elevated Th concentrations, present as thorite and Th-rich monazite. For efficient, resource-specific mining strategies, optimal ore types include: biotite-altered disseminated ores in the Main Open Pit and the disseminated and massive ores in the West Open Pit for Th-REE-Nb, and massive ores in the Main and East open pits for Th-Fe-REE.&lt;/div&gt;&lt;div&gt;Moreover, Th concentrations closely align with REE and Fe but diverge sharply from Nb. Thorium-REE-rich minerals mainly occur in fluorite-rich banded and massive ores, while Nb-bearing minerals concentrate in ores dominated by aegirine and riebeckite, linked to alkaline metasomatism. Geochemical analyses reveal a strong Th-F correlation but no association with K&lt;sub&gt;2&lt;/sub&gt;O or Na&lt;sub&gt;2&lt;/sub&gt;O, which highlighting distinct enrichment-precipitation pathways: the Th-REE-Fe systems rely on fluorination-driven, contrasting sharply with Nb’s alkaline metasomatic origins. These insights guide targeted exploitation strategies and deepen understanding of the deposit’s complex metal","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106883"},"PeriodicalIF":3.6,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145060397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid inclusion, stable isotope and tourmaline chemistry at Gadag Gold Field, Dharwar Craton, India: Implications for metamorphic origin of auriferous fluid","authors":"Debasis Pal ,&nbsp;Manash Jyoti Saikia ,&nbsp;Sakthi Saravanan Chinnasamy ,&nbsp;Dnyaneshwar Gaonkar ,&nbsp;Manish M. John","doi":"10.1016/j.oregeorev.2025.106876","DOIUrl":"10.1016/j.oregeorev.2025.106876","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The sources of auriferous fluid and metal in orogenic gold deposits have long been a subject of debate. This paper investigates the Gadag Gold Field (GGF) in the western Dharwar Craton, India—a representative greenstone-hosted orogenic gold system—to understand the gold forming process. The litho associations (metabasalt, &lt;em&gt;meta&lt;/em&gt;-argillite and BIF) and spatial distribution of GGF demands a deposit specific study, while other orogenic gold deposits are in the eastern Dharwar Craton. The nature and sources of the auriferous ore fluid in GGF are still arguable and require further constraints. The GGF comprises three auriferous lodes (western, central, and eastern), hosted in metabasalt, argillite, and banded iron formation (BIF), respectively. Despite lithological differences in host rock, the western and central lodes show similar alteration assemblages (quartz + carbonate + muscovite + chlorite + sericite ± tourmaline + arsenopyrite + pyrite + chalcopyrite ± sphalerite).&lt;/div&gt;&lt;div&gt;Petrography and microstructures indicate two stages of mineralization corresponds to progressive D&lt;sub&gt;3&lt;/sub&gt; dextral shearing. Where stage-1 is followed by stage-2 during progressive deformation. Although visible native gold grains are rare, electron microprobe analysis of arsenopyrite reveals the presence of structure-bound invisible refractory gold in the GGF. Detailed fluid inclusion (FI) studies on quartz-carbonate veins reveal a low- to medium-saline (0.04–9.6 wt% NaCl equiv.), reduced H&lt;sub&gt;2&lt;/sub&gt;O-NaCl-CO&lt;sub&gt;2&lt;/sub&gt; ± CH&lt;sub&gt;4&lt;/sub&gt; fluid, with evidence for fluid immiscibility. Estimated mineralization conditions (1.2–2.0 kbar, 275–333 °C) from fluid inclusion and chlorite thermometry is consistent with greenschist-facies alteration. Tourmaline geochemistry (Na&lt;sub&gt;avg&lt;/sub&gt; ∼ 0.68 apfu, low Fe&lt;sup&gt;3+&lt;/sup&gt;/Fe&lt;sup&gt;2+&lt;/sup&gt;, Fe-Mg ratio) and coeval sulfides from the mineralized zone reflect the characteristics of low saline, reduced fluid and partitioning of Fe into chlorite and sulfides during fluid-rock interaction with Fe-rich metabasalt is also inferred.&lt;/div&gt;&lt;div&gt;The similar and overlapping ranges of δ&lt;sup&gt;34&lt;/sup&gt;S isotopic data between mineralized sulfide grains (+1.5 to +4.5 ‰) and host rock pyrites (–1 to +3.8 ‰), suggest the dissolution of preexisting magmatic and metasedimentary pyrites of the host rocks during high fluid flux contributed most of the sulfur in the hydrothermal system. While carbon isotope values (δ&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;fluid&lt;/sub&gt;: −6.0 to +1.5 ‰) indicate that the carbon was sourced from a well-buffered and isotopically homogeneous fluid reservoir, most likely maintained by interaction with carbonate-bearing lithologies present in the study area and/or a deep-seated metamorphic fluid system. These isotopic signatures, combined with tourmaline and FI data, predominantly support metamorphogenic origin of the auriferous fluid at GGF, though influences of magmatic fluid could not be completely ruled out. Where gold was like","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106876"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alteration characteristics and short wavelength infrared (SWIR) spectroscopy of the Huangtupo Cu-Zn VMS deposit, NW China: Implications for ore genesis and exploration","authors":"Jiaxuan Zhao ,&nbsp;Dianming Zhang ,&nbsp;Ligang Pu ,&nbsp;Juan Shen ,&nbsp;Xiaoliang Yu ,&nbsp;Yaoxuan Wang ,&nbsp;Bing Xiao","doi":"10.1016/j.oregeorev.2025.106886","DOIUrl":"10.1016/j.oregeorev.2025.106886","url":null,"abstract":"<div><div>The Huangtupo Cu-Zn deposit is a typical Early-Paleozoic volcanogenic massive sulfide (VMS) deposit situated in Eastern Tianshan, within the Central Asia Orogenic Belt. Based on the paragenetic sequence reflected by mineral assemblages and their textural characteristics, the alteration and mineralization processes at Huangtupo can be categorized into two major periods comprising eight distinct stages: the VMS period (including the premineralization stage S1, stockwork ore stage S2, massive sulfide ore stage S3, and barite stage S4), and the late hydrothermal overprinting period (encompassing the albite stage S5, silicification stage S6, chlorite + epidote stage S7, and carbonate stage S8). By correlating petrographic investigation and short-wave infrared (SWIR) spectral analysis, five alteration/mineralization zones have been distinguished along the vertical profile, characterized by: Zone I (albite-white mica-chlorite zone), Zone II (albite-white mica-chlorite-epidote zone), Zone III (chlorite-pyrite ± white mica zone), Zone IV (massive sulfide zone), and Zone V (pyrite-quartz-white mica zone). Alteration and mineralization features indicate that Huangtupo is a highly overprinted sub-seafloor replacement VMS deposit.</div><div>SWIR spectrometry shows that chlorite and white mica are the primary alteration minerals in Huangtupo. For white mica, the position of Al-OH absorption feature (Pos2200) exhibits a spectral shift between 2198 and 2214 nm which is interpreted to reflect a compositional trend spanning from paragonite towards phengite. The illite crystallinity (IC) values of white mica vary from 0.79 to 3.11. For chlorite, the position of Fe-OH absorption feature (Pos2250) ranges from 2241 to 2253 nm, indicating Mg-rich to Mg-Fe chlorite compositions. Proximal to massive sulfide mineralization, white mica exhibits shorter Pos2200 (wavelengths below 2202 nm) and higher IC values (1.4–2.1). Additionally, chlorite near the ore body is typically predominantly Mg-rich (wavelengths below 2250 nm), though no significant spatial variation pattern is observed. These findings suggest that white mica formed under high-temperature, acidic conditions near massive sulfides, while chlorite formation was likely influenced by Mg-rich seawater infiltration. The alteration mineral assemblage in the hanging wall may reflect subsequent overprinting by porphyry-like hydrothermal fluids. This study highlights the coexistence of VMS and porphyry-type mineralization potential at Huangtupo, providing a valuable case for SWIR applications in ancient sub-seafloor replacement VMS systems.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106886"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of regolith-hosted Nb-REE deposits in alkaline rocks using multisource spectroscopic system: A case study of the Puxiong deposit, Yunnan Province, China","authors":"Jin Hu ,&nbsp;Dai Zhang ,&nbsp;Jia-Xi Zhou ,&nbsp;Min Wang","doi":"10.1016/j.oregeorev.2025.106860","DOIUrl":"10.1016/j.oregeorev.2025.106860","url":null,"abstract":"<div><div>Regolith-hosted rare earth element (REE) deposits are of global strategic importance, with China supplying over 90% of the world’s medium and heavy REEs. However, exploration in subtropical regions is hindered by dense vegetation, variable weathering intensities, and complex lithological settings. This study addresses these challenges by focusing on the Puxiong Nb-REE deposit in Yunnan Province, China, and by employing a cost-effective methodology that integrates ASTER and Sentinel-2 multispectral data with ALOS PALSAR DEM and GF-3 SAR imagery. As a complementary to hyperspectral and airborne approaches, our method demonstrates the feasibility of extracting REE-related information from multisource remote sensing data. Techniques including band ratio analysis, principal component analysis (PCA), constrained energy minimization (CEM), directional filtering, and K-means clustering were combined with geological and geomorphological data to delineate potential REE zones. A key innovation of this study is the use of Nd³⁺ abundance as a direct tracer for Nb-REE localization, enhanced by a regression model that incorporates indicator minerals (e.g. kaolinite, montmorillonite, hematite, chlorite, calcite, illite, and halloysite) to refine predictions. The integration of ALOS PALSAR DEM enabled detailed geomorphological analysis, while GF-3 SAR imagery improved the detection of structural features, further refining the delineation of potential zones. Results reveal a strong spatial correlation between Nd³⁺-rich areas and favorable lithological units, such as alkaline rocks and residual slope deposits, as well as regions with moderate-to-high indicator mineral assemblages abundance. Six high-potential zones were identified, including the Changlinggang-Baiyunshan and Jiasha areas, with validation by comparison against known<!--> <!-->geochemical datasets confirming the accuracy of these predictions. The proposed multi-factor constrained model highlights the potential for scalable and efficient exploration of regolith-hosted REE deposits, particularly in subtropical regions, by integrating multisource remote sensing and geological insights. This study provides a robust framework for enhancing exploration strategies for regolith-hosted Nb-REE deposits across diverse metallogenic environments.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106860"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145044980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of the first high-sulfidation epithermal ore-bearing lithocap in the western section of the Gangdese metallogenic belt and its significance","authors":"Nan Wang ,&nbsp;Juxing Tang ,&nbsp;Zhibo Liu ,&nbsp;Yang Song ,&nbsp;Jingjing Dai ,&nbsp;Baolong Li ,&nbsp;Xudong Ma ,&nbsp;Zhijun Li ,&nbsp;Xukun Yan ,&nbsp;Qingfei Sun","doi":"10.1016/j.oregeorev.2025.106885","DOIUrl":"10.1016/j.oregeorev.2025.106885","url":null,"abstract":"<div><div>Several lithocaps have been recently identified in the western section of the Gangdese metallogenic belt (GMB) and can be used to guide exploration of porphyry-high sulfidation epithermal deposits. In this work, we report the first ore-bearing lithocap (Mangla) within the GMB and carry out field mapping, geochronology, and shortwave infrared reflectance spectroscopy analyses. The zircon U-Pb (16.93 Ma) and alunite ⁴⁰Ar-³⁹Ar (19.24 Ma) isotope ages reveal that the protoliths and alteration of the Mangla lithocap occurred during one Cenozoic magmatic event, which corresponds with the mineralization ages of porphyry-skarn copper-polymetallic deposits in the eastern GMB. The alteration mineral assemblages, including alunite, dickite, pyrophyllite, kaolinite, and diaspore, along with enargite, colusite, Cu-S binary system minerals covellite and digenite, chalcopyrite and bornite, validate the characterization of a typical high-sulfidation epithermal mineralization system. Laterally, several alteration centers have been identified at the surface, and the vertical alteration is composed of deep high-temperature mineral assemblages (pyrophyllite + diaspore + topaz) that shift upward to low-temperature minerals, which are influenced primarily by faults, elevation, lithological permeability, fluid cooling and pH reduction. Notably, the vuggy quartz ± alunite and alunite + pyrophyllite zones within the lithocap are favorable locations for copper–gold mineralization, and a comprehensive epithermal mineralization system is preserved in this area, indicating the potential for underlying deep porphyry systems. Considering the presence of extensive continental volcanic coverage and notable analogous alteration features in the region, we assert that the area of Miocene continental volcanic rocks in northwestern Xizang presents substantial potential for copper–gold exploration.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106885"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genesis and ore-forming processes of Dulong Sn polymetallic skarn deposit: Constraints from u-pb dating and trace elemental analyses of zircon, garnet and cassiterite","authors":"Qingmei Wang ,&nbsp;Yan Cheng ,&nbsp;Zhengliang Yang ,&nbsp;Mingguo Deng ,&nbsp;Wenchang Li ,&nbsp;Zhen Jia ,&nbsp;Junbao Luo ,&nbsp;Feiyang Xu ,&nbsp;Fuchuan Chen","doi":"10.1016/j.oregeorev.2025.106884","DOIUrl":"10.1016/j.oregeorev.2025.106884","url":null,"abstract":"<div><div>The Dulong Sn polymetallic skarn deposit, situated at the southern extremity of Gejiu-Malipo Sn-W metallogenic belt, is a representative skarn Sn polymetallic deposit in SW China. However, due to various types of magmatism and metal mineralization in Dulong deposit, the genetic link between different magmatism (TMMG and GP), skarnization and Sn mineralization (skarn-type and vein-type) has not been established. In this study, Zircons from TMMG and GP, hydrothermal garnet, skarn-type and vein-type cassiterite in Dulong deposit were picked for in-situ U-Pb isotopic and elemental analyses, to constrain the ore genesis and ore-forming processes. As results, the TMMG in the Dulong Sn polymetallic deposit yields a U-Pb age of 88.56 ± 0.33 Ma, and the GP yields a younger age of 82.47 ± 0.61 Ma. The hydrothermal garnet yields a U-Pb age of 88.2 ± 2.9 Ma. Whereas the skarn-type cassiterite coexisting with magnetite and the skarn-type cassiterite coexisting with sulfide yielded a U-Pb age of 87.50 ± 1.00 Ma and 87.00 ± 1.40 Ma, respectively. Meanwhile, the vein-type cassiterite yielded a U-Pb age of 81.50 ± 2.50 Ma. The above dating results probably suggest that two-mica monzonitic granite is responsible for skarnization and skarn-type Sn mineralization, while granitic porphyry is responsible for vein-type Sn mineralization. Zircons from two-mica monozonitic granite and granitic porphyry in Dulong Sn polymetallic deposit is characterized by low ΔFMQ values and Eu/Eu*, Ce⁴⁺/Ce³⁺, Ce/Nd)/Y ratios, indicating that the causative magma resources have low oxygen fugacity and low initial water content, and the Sn mineralization potenital of TMMG is significantly greater than GP. The elemental changes from core to rim in hydrothermal garnet grains reveal that early ore-forming fluids originating from magma were more acidic and reducing. During the evolution processes, significant meteoric water continuously mixed into the ore-forming fluid, which was the potential mechanism controlling ore precipitation in Dulong deposit.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106884"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prospectivity mapping and exploration targeting for sediment-hosted Pb–Zn deposits in NW Guizhou of SW China using an integrated machine learning framework","authors":"Xin Zhang ,&nbsp;Yu-Miao Meng ,&nbsp;Xiao-Wen Huang ,&nbsp;Ruizhong Hu ,&nbsp;Xianwu Bi ,&nbsp;Chuan-Yuan Liu ,&nbsp;Bin Guo","doi":"10.1016/j.oregeorev.2025.106882","DOIUrl":"10.1016/j.oregeorev.2025.106882","url":null,"abstract":"<div><div>Northwestern (NW) Guizhou in SW China hosts more than 100 Pb-Zn deposits which are primarily small in scale. In recent years, the discovery of a few large to super-large Pb-Zn deposits has revealed significant mineralization potential. It is thus necessary to reevaluate the mineral prospectivity using advanced predictive methods. This study presents an integrated machine learning framework that combines deep learning (DL), traditional machine learning (TML), and unsupervised deep learning via a variational autoencoder (VAE) for high-precision Pb-Zn prospectivity mapping in NW Guizhou. A total of 135,385 high-density soil geochemical samples (17 elements) with structural datasets are used to establish 18 evidence layers for hierarchical mineral potential assessment. Using four-fold cross-validation, this study shows that both the DL model trained on 5 × 5 km multi-channel image patches and the TML models utilizing 1–2 km buffer-processed numerical data achieved accuracies of 90 % or above on the test set. In practical application, the DL prospectivity map delineated high-confidence prospect areas more precisely than the TML models, suppressed background noise more effectively and captured nearly 90 % of known deposits. Although the TML model shows slightly lower prediction success rates (∼80 %), it provides smoother anomaly transition and identifies local anomalies in the target area. The integration of VAE with mineralization-related elements further enhances the system’s capability, enabling anomaly detection, improving the contrast of target areas, and refining them to kilometer-scale precision. Through the integration of the machine learning methods, this study successfully generates high-precision prospectivity maps and optimizes target areas at a kilometer scale, offering significant insights for sediment-hosted Pb-Zn deposit exploration.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"186 ","pages":"Article 106882"},"PeriodicalIF":3.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}