Ore Geology Reviews最新文献

{"title":"Failed genesis of a Fe-skarn deposit caused by redox states of intrusion and wall rocks (Torre di Rio, Island of Elba, Italy)","authors":"Paolo S. Garofalo , Daniele Redi , Nikita Malafeevskiy , Gunnar Schwarz , Christoph Neff , Peter Keresztes Schmidt , Detlef Günther","doi":"10.1016/j.oregeorev.2025.106446","DOIUrl":"10.1016/j.oregeorev.2025.106446","url":null,"abstract":"<div><div>The Torre di Rio skarn (Island of Elba, Italy) is a pyroxene-ilvaite-epidote skarn that hosts a Fe-oxide mineralization and is the type locality of the mineral <em>ilvaite</em>. In contrast with other Fe deposits of the island, it belongs to a group of subeconomic skarns. We combine surface mapping, petrographic data, scanning electron microscope and electron probe microanalyses, fluid inclusion microthermometry, elemental imaging by Laser Ablation-Inductively Coupled Plasma - Time of Flight Mass Spectrometry (LA-ICP-TOFMS), and fluid-mineral equilibria to compare the genesis of this skarn with that of typical economic skarns.</div><div>Fieldwork shows that Torre di Rio consist of ilvaite-, ilvaite-pyroxene, and pyroxene-epidote zones. The epidote-rich zone is in contact with the wall rocks, i.e., a sequence of pelites, marls, marbles, and other sedimentary lithologies. The 6.53–5.9 Ma Porto Azzurro monzogranite is the reduced (ilmenite-bearing) causative intrusion of the skarn, which induced contact metamorphism in the wall rocks at 6.7–6.2 Ma. Torre di Rio formed within the biotite-white mica-chlorite metamorphic zone, a few hundred meters from the contact with Porto Azzurro.</div><div>Within the skarn, ilvaite and pyroxenes are both euhedral and arranged in rosettes and spheroids. Ilvaite has a consistent chemical composition with a significant Mn enrichment close to the wall rocks, and pyroxene is hedenbergitic. The epidote is euhedral and occurs as epidote s.s. and allanite-(Ce). Late phases are albite, annite, phengite, chlorite, quartz, calcite, and chalcedony. Magnetite and hematite form spheroid textures or are finely mixed. Euhedral pyrrhotite and pyrite host native Bi and Pb.</div><div>Seventeen calcite- and quartz-hosted fluid inclusion assemblages from the ilvaite skarn zones are associated with the magnetite and hematite aggregates. At room temperature, all assemblages are two-phase (L-V). Fourteen of them show constant phase proportions and three show variable proportions. The assemblages with constant phase proportions have salinities between 0.8 and 17.0 mass% NaCleq and homogenize by bubble disappearance between c. 150 and 300 °C. The assemblages with variable phase proportions homogenize by bubble and liquid disappearance between 280 and 330 °C.</div><div>Element imaging by LA-ICP-TOFMS of ilvaite and quartz from skarn spheroids shows that several lithophile (e.g., Al, Mg) and siderophile (e.g., As, Ge, Ga, In, Sb) trace elements occur at concentrations between c. 20 μg/g and 1 wt%.</div><div>We interpret our dataset as a product of a shallow skarn that formed under extremely reducing conditions, which were controlled by the redox nature of both Porto Azzurro and wall rocks. At these conditions, supersaturation of pyroxenes and ilvaite within the skarn was achieved as a result of phase separation, cooling, and mixing of batches of heterogeneous and homogeneous ore fluids at about 350–150 °C. A Fe-skarn deposit failed ","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106446"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149625","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":"Petrogenesis of the Dapingtianshan intrusive complex, South China: Geochemistry, zircon U-Pb geochronology, Sr-Nd-Hf-O isotopes, and implications for geodynamic setting and mineralization","authors":"Gang Chen ,&nbsp;M. Santosh ,&nbsp;Changhui Ke ,&nbsp;Maohong Chen ,&nbsp;Rui Ge","doi":"10.1016/j.oregeorev.2025.106449","DOIUrl":"10.1016/j.oregeorev.2025.106449","url":null,"abstract":"<div><div>The petrogenesis, tectonic setting and associated mineralization of magmatic suites associated with the subduction of the Paleo-Pacific plate have been topics of considerable debate. Hence, we explore the Dapingtianshan intrusive complex in South China, a composite intrusion with granodiorite in the margin and monzonite in the core. Geochemical features indicate typical I-type and high-K calc-alkaline characteristics, including abundant mafic microgranular enclaves (MMEs). Zircon U–Pb ages of 96.9 ± 0.3 Ma and 96.2 ± 2.9 Ma for the monzonite and MMEs suggest coeval magmatism. Biotite from both exhibits similar compositions, crystallizing at 700–750 °C. The monzonite and MMEs are metaluminous (A/CNK = 0.68–1.05), with trace element patterns showing enrichments in Rb, U, and Nd and depletions in Ba, Nb, Sr, P, and Ti. Chondrite-normalized REE distribution patterns reveal LREE enrichment and negative Eu anomalies. Zircon analyses show monzonite εHf(t) values of −2.4 to 0.6 and δ¹⁸O values of 5.6 to 8.6. MMEs exhibit εHf(t) values of −3.0 to 3.6. Sr-Nd isotopes suggest isotopic equilibrium during magma mixing, with (87Sr/86Sr)i of 0.70831 to 0.71426 and εNd(t) of −5.6 to −4.6. Findings suggest magma involvement of partial melts from the Mesoproterozoic metamorphic basement and enriched lithospheric mantle metasomatized by sediment-related melts linked to the subduction of the Pacific plate. Combining these results, we propose that the Dapingtianshan complex potentially hosts magmatic-hydrothermal Au–Ag–Cu–Pb–Zn metallogenic systems. The study hints at the extension of the Cu–Au metallogenic belt from the Dayaoshan area to the Qin-Hang metallogenic belt and South China.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106449"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149130","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":"Pyrite geochemistry for deposit type prediction and exploration in the Golden Triangle, northwest British Columbia, Canada","authors":"Christopher J.M. Lawley ,&nbsp;Duane C. Petts ,&nbsp;Well-Shen Lee ,&nbsp;Stefanie Brueckner","doi":"10.1016/j.oregeorev.2025.106447","DOIUrl":"10.1016/j.oregeorev.2025.106447","url":null,"abstract":"<div><div>Mineral exploration in remote mountain belts represents an exceptional challenge due to high operational costs, limited accessibility, and complex geology. New tools are urgently needed to improve discovery rates in these types of highly prospective but challenging mineral exploration frontiers. Herein we apply deep learning to predict deposit types in a rugged and remote part of northwest British Columbia (Canada) based on laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis of pyrite to address that knowledge gap. The combined pyrite dataset represents four mineral deposit types at various stages of development, including porphyry copper-gold (i.e., Galore Creek, Copper Canyon, Kerr, Mitchell, Sulphurets, Iron Cap), epithermal gold-silver (i.e., Brucejack), magmatic nickel-copper (i.e., E&amp;L), and volcanogenic massive sulphide copper-lead-zinc (i.e., A6). Trace element mapping, spot analysis, and quantitative mineralogy are applied to characterize the petrogenetic context and composition of each pyrite sample. Geochemical data were first pre-processed with principal component analysis and autoencoders to extract new features from the training data. The pre-processed pyrite data were then combined to train a series of feed-forward artificial neural networks to predict deposit types. The preferred deep learning classification model yields an overall accuracy of 99% for a subset of pyrite analyses that were not included in the training process. We then apply that classifier to show that hydrothermally altered rocks from early-stage mineral exploration projects (i.e., Dok and Yeti) are most likely related to porphyry copper-gold mineralization based on the composition of pyrite. Statistical analysis of the model results further demonstrates that pyrite morphology, texture, grain size, and paragenesis are important predictors of deposit type when combined with trace element concentrations and the new latent variables identified by the preferred autoencoder. We suggest that the pyrite library and modelling methodology can be used to support early-stage mineral targeting in remote exploration frontiers that are prospective for a range of deposit types.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106447"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149621","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":"Quartz geochemical constraints on the origin of stratabound deposits, Eastern China: Insights from the Xinqiao deposit","authors":"Shuling Song ,&nbsp;Yu Zhang ,&nbsp;Ke Chen ,&nbsp;Hongjie Shen ,&nbsp;Hongtao Zhao ,&nbsp;Lianjie Zhao","doi":"10.1016/j.oregeorev.2025.106474","DOIUrl":"10.1016/j.oregeorev.2025.106474","url":null,"abstract":"<div><div>Stratabound deposits with origin-undetermined footwall quartz-pyrite stockwork mineralization in the Middle-Lower Yangtze River Valley metallogenic belt (Eastern China) have uncertain metallogenic models. The Xinqiao deposit, a notable example in the Tongling ore district, provides an ideal case for studying the footwall stockwork mineralization to elucidate the origin of the stratiform mineralization. Cathodoluminescent imaging reveals three generations of quartz within the Xinqiao stockwork mineralization: homogeneous quartz (Qz1), oscillatory-zoned quartz (Qz2) coexisting with pyrite and enclosing Qz1, and weakly oscillatory-zoned quartz (Qz3) replacing Qz2. Quartz trace elements geochemistry (high Al (65.1–2849 ppm) and Ti (3.10–90.9 ppm), low Mn (0.980–20.0 ppm), As (1.56–10.2 ppm), and Sb (0.123–5.21 ppm)), combined with quartz-pyrite assemblage, suggests a magmatic-hydrothermal origin for the stockwork mineralization linked to the Early Cretaceous Jitou stock. Variations in Ti, Ge/Ti, and Al contents across three quartz generations indicate a temperature increase from Qz1 to Qz2 (&gt;400 ℃), followed by a decrease (&lt;350 ℃) during Qz3 formation, accompanied by a continuous pH decline. The injection of high-temperature magmatic-hydrothermal fluid would trigger the rapid crystallization of Qz1 with high trace elements (e.g., Fe, Cu, Zn, and Pb) during initial infiltration and hydraulic fracturing. A subsequent fluid pulse with minor meteoric water precipitate pyrite and Qz2, while meteoric water dominance during a waning magmatic-hydrothermal system led to Qz3 formation. These findings highlight the utility of quartz textures and trace element geochemistry in reconstructing the mineralization history and providing insights into the ore genesis in stratabound deposits within the Middle-Lower Yangtze River Valley metallogenic belt and similar metallogenic settings globally.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106474"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149132","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 Lengshuikeng porphyry type Ag-Pb-Zn-Cd deposit: Insights from magmatism-mineralization timing sequence, chemical composition and in-situ Pb isotope of sulfide","authors":"Lifei Yang ,&nbsp;Zherong Liu ,&nbsp;Zenghua Li ,&nbsp;Yongpeng Ouyang ,&nbsp;Qi Chen ,&nbsp;Bin Du ,&nbsp;Rubin Zhang ,&nbsp;Huijuan Zhang ,&nbsp;Chaowei Luo ,&nbsp;Jin Guo","doi":"10.1016/j.oregeorev.2025.106460","DOIUrl":"10.1016/j.oregeorev.2025.106460","url":null,"abstract":"<div><div>The Lengshuikeng deposit is a significant Ag-Pb-Zn-Cd deposits in the Gan-Hang Tectonic Belt (GHTB). Understanding its genesis is crucial for revealing the relationship between the tectonic evolution and the mineralization in this region. However, the metallogenesis of the Lengshuikeng deposit has remained unclear. To address this issue, a systematic analysis of chronological data, mineralogy, lithology, chemistry of sphalerite, and in-situ Pb isotope of the sulfides from the Lengshuikeng deposit are conducted to explore the relationship between magmatism and mineralization, metal sources, and ore-forming feature. The magmatism consists of two major stages: the Late Jurassic (Daguding Formation and a large scale of granite porphyry) and the Early Cretaceous (E’huling Formation and minor acid dyke). The mineralization age is restricted near 155 Ma, which is in keeping with the granite porphyry (158.0 ± 1.0–154.3 ± 3.0 Ma). The sulfides in the major stage (Gn-Sp(−Aca)-Py) (²⁰⁸Pb/²⁰⁴Pb: 38.07–38.44, ²⁰⁷Pb/²⁰⁴Pb: 15.48–15.62, ²⁰⁶Pb/²⁰⁴Pb: 17.68–17.90, ²³⁸U/²⁰⁴Pb (μ): 9.32–9.58, ²³²U/²⁰⁴Pb (ω): 38.06–40.16) exhibit consistent Pb isotopes with most of the granite porphyry and minor crystal tuff, which indicates that the metals primarily came from the granite porphyry. The crystal temperature of sphalerite is focused on 300–350°C. In consideration of C, H, and O isotopes in previous works, the hydrothermal fluid was primarily derived from the granite porphyry at a high temperature stage. Combined with the trace elements of sphalerite (relatively high Cu, Fe, In, Cd, low Ge and Mn) and the genesis diagrams (based on In, Ga, Ge, Fe, Cd, and Mn), this deposit is classified as a porphyry type deposit. Geochemical data, Nd isotopes in previous works and in-situ Pb isotopes (△β-△γ; V₁-V₂) from this research suggest that the granite porphyry and crystal tuff mainly emplaced by partial melting of the Neoproterozoic basement in compressive setting at the GHTB, resulting from the subduction of the Pacific Plate to the South China Craton. A comprehensive metallogenic model is defined, involving the tectonic setting, the genesis of granite porphyry, ore-controlling factors, and the mineralization process.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106460"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149685","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":"Reply to Comment on “Baddeleyite U-Pb age and Hf isotopes, and constraints on genesis of the Panzhihua carbonatite in SW China” by Arndt, Ganino and Li","authors":"Shengwei Wang ,&nbsp;Xiaoming Sun ,&nbsp;Yanguang Li ,&nbsp;Li Xu ,&nbsp;Yu Fu ,&nbsp;Cong Feng ,&nbsp;Guodong Xu ,&nbsp;Zhizhong Hu ,&nbsp;Guotao Ma ,&nbsp;Shenglin Lu","doi":"10.1016/j.oregeorev.2024.106428","DOIUrl":"10.1016/j.oregeorev.2024.106428","url":null,"abstract":"<div><div>The calcareous rocks adjacent to the Panzhihua intrusion were considered as carbonatite rather than marbles/skarns based on detailed field mapping and profile survey. <span><span>Arndt et al. (2023)</span></span> presented data and figures to compare the difference of trace elements of carbonatite between Panzhihua (they called “dolomite” or “marble”) and other areas in the world and maintained their genesis interpretation. However, carbonatite and carbonate can’t be well distinguished by the trace elements and Hf isotope, because that only approximately 20 % occurrences of global carbonatites contain high contents of rare earth elements. The mineral composition, major element, Ni (avg. 1011.91 ppm), Cr (avg. 1762.73 ppm), and ∑PGE (avg. 12.95 ppm) contents of the dark ultramafic enclaves hosted in the white calcareous rocks indicate that they are mantle-derived xenoliths rather than dolerite (or gabbro and diabase) or metamorphosed peridotite. The large number of mantle xenoliths also implies that their surrounding rock is more likely to be mantle-derived magmatic rock (i.e. carbonatite) rather than skarn. Furthermore, from melanocratic xenolith core and leucocratic surrounding carbonatite to middle zebra rocks, only physical rather than chemical change (i.e. contact metamorphism) happened due to without obvious mineral composition variation.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106428"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148342","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 origin of lithium in hydrothermally overprinted Li-rich strata in the Mesoproterozoic Wumishan Formation: Insights from radiogenic and stable isotopes","authors":"Fei Xu ,&nbsp;Hanjie Wen ,&nbsp;Hefan Liu ,&nbsp;Ni Tao ,&nbsp;Yu Chen ,&nbsp;Jianghao Yan ,&nbsp;Baoqiang Zhao","doi":"10.1016/j.oregeorev.2025.106448","DOIUrl":"10.1016/j.oregeorev.2025.106448","url":null,"abstract":"<div><div>Significant lithium (Li) enrichment has been observed in specific strata of the Mesoproterozoic Wumishan Formation in North China, yet the mechanisms and origins of this enrichment remain contentious. Our previous mineralogical microscopic studies suggested that post-depositional hydrothermal fluids are crucial for Li enrichment; however, a lack of macroscale geological evidence, such as metasomatic textures, necessitating further isotopic investigation. This study compares the geochemical characteristics of Li-rich and Li-poor samples, utilizing Sr-Nd-Pb and Li isotopes, along with major and trace elements, to elucidate the enrichment mechanisms and sources of Li. Nd isotopic data reveal that the primary sedimentary sources of the Wumishan Formation strata are predominantly felsic components (ε_Nd(0): –15.64 to –24.83), with an contributions from basic weathering products (ε_Nd(t): –8.13 to 2.63). However, the Li-rich samples exhibit anomalously high enrichments of Sr (⁸⁷Sr/⁸⁶Sr: 0.7340–0.7844) and Pb isotopes (²⁰⁶Pb/²⁰⁴Pb: 18.939–32.520; ²⁰⁷Pb/²⁰⁴Pb: 15.822–17.087; ²⁰⁸Pb/²⁰⁴Pb: 38.311–49.381), along with homogeneous positive δ⁷Li values (+5.59 ‰ to + 6.93 ‰). The pronounced enrichment of radiogenic Sr and Pb isotopes, coupled with the absence of Li isotopic fractionation in clay minerals, strongly support the hypothesis that Li enrichment is associated with post-depositional hydrothermal alteration. Additionally, positive correlations between Li and trace elements (e.g., F and Rb), further reinforce this association rather than suggesting a link to chemical weathering. High ⁸⁷Sr/⁸⁶Sr and ²⁰⁸Pb/²⁰⁴Pb ratios, along with positive δ⁷Li values, imply that Li likely originates from the leaching of surrounding rocks. Conversely, differences in Sr, Nd, Pb, and Li isotopes between diorite and diabase confirm minimal contribution from magmatic sources. This study provides new insights into the genesis of Li-rich strata in the Wumishan Formation, further supporting our previous mineralogical evidence and offering significant geological implications for their exploration and exploitation.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106448"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149624","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":"Distribution, occurrence and enrichment mechanism of Co in Fe-Ti oxide deposits: An example from the giant Hongge deposit, SW China","authors":"Zhongcheng Zhang ,&nbsp;Xinlu Hu ,&nbsp;Banxiao Ruan ,&nbsp;Xinbiao Lv ,&nbsp;Ruiqin Liu","doi":"10.1016/j.oregeorev.2025.106465","DOIUrl":"10.1016/j.oregeorev.2025.106465","url":null,"abstract":"<div><div>Magmatic Fe-Ti oxide deposits are recognized as a potential significant source of Co. However, the distribution, occurrence state and enrichment mechanism of Co within these deposits are not well understood. The Hongge deposit, one of the world’s largest Fe-Ti oxide deposits, has an estimated Co reserve of 488,400 tons and an annual production of Co concentrates of 20,000 tons. Based on comprehensive analyses across various scales from lithologies to rocks and minerals, this study aims to elucidate the occurrence state and enrichment mechanism of Co in Fe-Ti oxide deposits. Among different rock types, the highest concentrations of Co are observed in massive ores, with an average of 280 ppm, followed by disseminated ores, olivine pyroxenite, pyroxenite, and gabbro. In silicate and oxide minerals, the abundance of Co decreases in the following order: olivine &gt; magnetite &gt; ilmenite &gt; amphibole &gt; pyroxene &gt; apatite and plagioclase. Among sulfide minerals, the Co content is ranked as follows: cobaltite (with Co contents ranging from 18.42 % to 25.80 %) &gt; pentlandite &gt; pyrite &gt; pyrrhotite &gt; chalcopyrite. Cobalt occurs as three primary forms: (1) an independent mineral, such as cobaltite (As_0.99∼1.10Co_0.55∼0.74Ni_0.20∼0.37S); (2) isomorphous substitution for Fe, Mg and V; (3) microscopic inclusions in magnetite and pyrrhotite. The processes contributing to the enrichment of Co include fractional crystallization, sulfide-silicate immiscibility, and hydrothermal alteration. Sulfide-silicate immiscibility plays a predominant role in the Co enrichment.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106465"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149686","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":"Newly recognized Late Jurassic Nb-Ta pegmatite dikes in the Maoershan-Yuechengling pegmatite district, south China: Their petrogenesis and metallogenesis","authors":"Chuan Zhao ,&nbsp;Wei Fu ,&nbsp;Xijun Liu ,&nbsp;Xiao Liu ,&nbsp;Meng Feng ,&nbsp;Yangyang Feng ,&nbsp;Pansong Gao ,&nbsp;Cheng Xu ,&nbsp;Chunzeng Wang","doi":"10.1016/j.oregeorev.2025.106470","DOIUrl":"10.1016/j.oregeorev.2025.106470","url":null,"abstract":"<div><div>The Maoershan-Yuechengling pegmatite district (MYPD) of south China contains more than 2000 pegmatite dikes, most of which show rare-metal mineralization, for example, Nb, Ta, Be, and Rb mineralization. However, petrogenesis of the pegmatite dikes and their rare metal metallogenesis remain unclear due to lack of reliable geochronological and geochemical constraints. In this paper, we report new data of whole-rock geochemistry, Nd-Pb isotopes, and columbite–tantalite (coltan) and zircon U-Pb ages of the pegmatite dikes and their hosting gneissic granite from the Mao’antang deposit, the largest Nb-Ta deposit known in the district. The Mao’antang pegmatite dikes occur in the Moshishui area in a linear distribution pattern due to fault structural control. The area are dominated by Caledonian granitoids and Neoproterozoic metasedimentary rocks. Two coltan U-Pb ages of the mineralized pegmatites (159.5 ± 5.4 Ma and 155.0 ± 2.7 Ma) obtained in this study distinct them from the well documented, episodic Precambrian to Mesozoic rare-metal pegmatites in south China, for example, the 832–827 Ma, 424–387 Ma, 248–198 Ma, 140–127 Ma, and 70–40 Ma mineralized pegmatites. The Mao’antang Nb-Ta pegmatites are much younger than their hosting granite which is dated at 417.2 ± 2.0 Ma in this study. The large age gap (262–258 million years) indicates no direct petrogenetic association between the pegmatites and their hosting granite. Geochemically, the pegmatites have high Rb/Sr (6.63–215.2) ratios but low Nb/Ta (0.07–0.98) and Zr/Hf (4.02–35.63) ratios, indicating that the pegmatites are highly evolved. The Nd (ε_Nd(t) = -9.8 to −4.6; T_DM2 = 1.35–1.79 Ga) and Pb (²⁰⁶Pb/²⁰⁴Pb = 18.267–20.497; ²⁰⁷Pb/²⁰⁴Pb = 15.628–15.834) isotopic data suggest that the parental magmas of the pegmatites were originated from a mixed source of Proterozoic crustal material with minor mantle-derived melts. Based on euhedral coltan grains, low ratios of Nb/Ta, and Zr/Hf, and the new geochronological data, it is proposed that the Mao’antang mineralized pegmatites were evolved by fractional crystallization from residual parental magmas. Late Jurassic Nb-Ta rare-metal pegmatites are notably uncommon in south China. Recognition of their occurrence not only confirms the episodic nature of the south China rare-metal mineralized pegmatites, but also guides future exploration strategy for rare metals in south China.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106470"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148351","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":"Simulation-based mineral prospectivity modeling and Gray Wolf optimization algorithm for delimiting exploration targets","authors":"Kamran Mostafaei ,&nbsp;Mahyar Yousefi ,&nbsp;Oliver Kreuzer ,&nbsp;Mohammad Nabi Kianpour","doi":"10.1016/j.oregeorev.2025.106458","DOIUrl":"10.1016/j.oregeorev.2025.106458","url":null,"abstract":"<div><div>Exploration targeting is a multi-step process concerned with delimiting progressively smaller areas that are prospective for the targeted mineral deposit type, capable of hosting a potentially economic deposit and deserving of exploration funds. In mineral prospectivity modeling (MPM), target delineation represents the final stage of a procedure designed to identify discrete, explorable areas of high discovery potential within a much larger area of interest, typically covering entire camps, districts or provinces. However, defining unbiased thresholds for discriminating between high, moderate and low priority exploration targets is not a straightforward task. To avoid human bias in this thresholding process, a more structured, automated approach is needed. This study presents a simulation-based approach to MPM that adapts the Grey Wolf Optimizer (GWO) algorithm, a swarm intelligence method capable of objectively delineating exploration targets from MPM results. Our approach aims to reduce bias by applying Monte Carlo Simulation to the assignment of robust weights to the predictor maps at the core of the MPM procedure. The GWO algorithm facilitates the classification and prioritization and enhances the accuracy and reliability of the resulting targets. The proposed procedure is demonstrated here using a porphyry copper (Cu) example from the Chahargonbad district, SE Iran. The results show that the GWO-based framework not only identifies high-priority exploration zones but also reduces the uncertainty inherent in traditional manual selection methods. As such, this novel approach contributes to both theoretical and practical advancements in the field of mineral exploration, offering a scalable solution that can be adapted to various geological settings.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"177 ","pages":"Article 106458"},"PeriodicalIF":3.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148352","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}