Ore Geology Reviews最新文献

{"title":"Short wavelength infrared (SWIR) of white micas as a vectoring exploration tool for the Jiaojia gold deposit, Jiaodong Peninsula: implications for district- to deposit-scale gold exploration","authors":"Hao Wang ,&nbsp;Junling Zhang ,&nbsp;Zhengjiang Ding ,&nbsp;Qibin Zhang ,&nbsp;Junfeng Zhao","doi":"10.1016/j.oregeorev.2025.106626","DOIUrl":"10.1016/j.oregeorev.2025.106626","url":null,"abstract":"<div><div>The disseminated-style gold deposit, as the primary mining deposit-type in the Jiaodong Peninsula, has the current exploration depth exceeding 4000 m. These deposits/orebodies are primarily hosted within the Mesozoic granitic intrusions adjacent to the regional faults. The Jiaojia gold deposit, as the most famous disseminated-style gold deposit in Jiaodong, presents widely white micas alteration assemblages comprising distal potassic zone, intermediate sericitization, and proximal pyrite-muscovite-quartz zone. The mineral chemistry of white micas from three alteration zones was analyzed using short-wave infrared spectroscopy (SWIR) and electron microprobe analysis, along with an evaluation of the physicochemical conditions governing their formation. From distal to the proximal alteration zone, the K/(K + Na + Ca) ratio of muscovite decreases, while the Fe + Mg content first decreases and then slightly increases. This variation indicates that, from the distal to the proximal alteration zones, the temperature of the hydrothermal fluid progressively decreased, while the oxygen fugacity evolved from oxidizing to reducing and then to weakly oxidizing conditions. In each alteration zone, there is no linear correlation between the Pos2200 (the Al-OH absorption feature at 2200 nm) and its composition (e.g., Si, Al_tot, Fe + Mg). Our thermodynamic simulations reveal that during each alteration stage, muscovite of different end-members can form, leading to the formation of mixed peaks in the Pos2200 region of the spectrum. In contrast, Illite crystallinity values (IC values), reflecting the crystallinity of the white mica, is controlled by fluid/rock ratio and can be used as vectors towards potential mineralization. Based on 3D mapping of IC values, the southwest part of Jiaojia gold deposit could represent the most potential mineralization location for deeper drilling. Integrating geological mapping and spectrum data, 180 ∼ 350 m proximal to potential ore bodies can be outlined using the criteria of IC values (IC &gt; 1.3), which could be predicted to gold endowment of disseminated deposits over the entire Jiaodong gold province, East China.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106626"},"PeriodicalIF":3.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851883","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":"Ambient noise tomography reveals deep ore-forming structures of shear zone-type gold deposits at Dongchuan, Kunming Province, China","authors":"Yao Liang ,&nbsp;Zhanwu Lu ,&nbsp;Si Chen ,&nbsp;Hongshuang Zhang ,&nbsp;Xiaoran Wang ,&nbsp;Guangwen Wang ,&nbsp;Wei Cai ,&nbsp;Lifu Cao ,&nbsp;Zilong Chen","doi":"10.1016/j.oregeorev.2025.106623","DOIUrl":"10.1016/j.oregeorev.2025.106623","url":null,"abstract":"<div><div>While fault systems constitute the critical plumbing systems in hydrothermal shear zone-hosted gold systems, their spatial architecture commonly remains poorly documented thus limiting the development of robust exploration models. This study investigates the deep-seated fault systems and ore-forming processes in the Dongchuan gold mining area using ambient noise tomography and seismic velocity analysis. A Shear wave velocity model reveals significant lateral heterogeneity, with low-velocity zones corresponding to fault zones, while high-velocity anomalies are associated with deeper magmatic intrusions. The detailed analysis of fault systems highlights their critical role in controlling the gold mineralization, as reflected by distinct high-velocity seismic anomalies. Our study clearly links the spatial distribution of gold deposits to brittle-ductile shear zones, suggesting that secondary faults facilitate the migration of magmatic hydrothermal fluids, contributing to the formation of gold mineralization. Our findings suggest a poly-phase nature nature of the metallogenic process, with contributions from magmatic, and mantle plume events. This study provides valuable insights into the structural controls and fluid migration pathways associated with shear zone-hosted gold deposits.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106623"},"PeriodicalIF":3.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898613","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":"Unsupervised geochemical characterisation of deeply weathered terrains and regolith-hosted REE deposits: Rationale and benefits for exploration","authors":"Tobias G. Bamforth ,&nbsp;Heta M. Lampinen ,&nbsp;Leah Lynham ,&nbsp;Nathan Reid ,&nbsp;Robert Thorne ,&nbsp;Mario Iglesias-Martínez ,&nbsp;Joël Brugger ,&nbsp;Brad Cribb ,&nbsp;Brett Hazelden ,&nbsp;Fang Xia","doi":"10.1016/j.oregeorev.2025.106634","DOIUrl":"10.1016/j.oregeorev.2025.106634","url":null,"abstract":"<div><div>The accurate characterisation of regolith materials is crucial for mineral exploration, yet distinguishing visually indistinct clay-rich samples can be challenging and labour-intensive. This study conducts unsupervised k-means clustering and principal component analysis (PCA) on a geochemical dataset of over 3000 regolith samples from the Splinter Rock rare earth element (REE) prospect, Western Australia, to determine how unsupervised statistical methods may expedite the characterisation of regolith samples across large, buried and/or regolith-hosted ore deposits. K-means clustering identified five laterally consistent regolith horizons at Splinter Rock, which were manually interpreted into three REE-barren transported horizons and two mineralized saprolite-saprock horizons. The mineralogical and metallurgical features of all 3000 samples were then extrapolated from hyperspectral and metallurgical data of a select few reference samples within their clusters, to provide a preliminary understanding of the deposit’s overall structure and properties. Despite being a first-order approach, this method highlighted several consistent, statistically robust and previously unidentified patterns across the entire prospect: 1) the highest REE grades exist predominantly in the granitic saprolite and saprock; 2) relative to the light REEs (La–Sm), the heavy REEs (Eu–Lu) experience enrichment at the saprolite-saprock boundary and depletion with increasing depth in the saprock; 3) optimal metallurgical conditions occur near this saprolite-saprock interface; 4) relative accumulation of the economically- and environmentally-important ‘magnet’ REEs (MagREE, Pr, Nd, Tb, Dy) occurs mostly in the saprock; and 5) relative MagREE enrichment can be linked to the formation of negative Ce anomalies at lower stratigraphic positions. Lastly, PCA facilitated the development of tailored geochemical ratios to classify future samples into their appropriate horizons. This study highlights unsupervised statistical analysis of existing geochemical data as a robust, rapid and effective first-pass method for classifying and characterising extensive sets of regolith samples, as well as an efficient method of outlining deposit-scale trends and zones of consistent economic REE enrichment in large regolith-hosted deposits/prospects.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106634"},"PeriodicalIF":3.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868556","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 zonation and mineralogy of the Dibaonamugang Lithocap: Implications for mineral exploration in the Duolong Ore District, NW Xizang (Tibet), China","authors":"Ming Zheng ,&nbsp;Juxing Tang ,&nbsp;Yang Song ,&nbsp;Zichen Li ,&nbsp;Xu Wang ,&nbsp;Hao Sun ,&nbsp;Zhibo Liu ,&nbsp;Jingjing Dai ,&nbsp;Qiuping Liu","doi":"10.1016/j.oregeorev.2025.106628","DOIUrl":"10.1016/j.oregeorev.2025.106628","url":null,"abstract":"<div><div>Lithocaps are usually formed at the top of porphyry–epithermal metallogenic systems, exhibiting distinctive mineral assemblages and white tones that render them a notable prospecting indicator for potential deep porphyry–type mineralization. The Dibaonamugang lithocap is the largest exposed hydrothermal alteration system in the Duolong Ore District of NW Xizang (Tibet), China; however, associated porphyry–epithermal mineralization has yet to be identified. In this study, detailed field work and microscopic examination, combined with 1:10,000 geological mapping, short–wave infrared spectroscopic testing, whole–rock geochemistry, and in situ LA–ICP–MS analysis, were conducted to examine the mineralogical and geochemical characteristics of the lithocap and its exploration indications. Our research revealed that the Dibaonamugang lithocap shows typical high–sulfidation epithermal alteration mineral assemblages and zonation patterns: Zone I, a typical residual silica core with massive and vuggy quartz–alunite; Zones II–IV show advanced argillic alteration with quartz–alunite–dickite–pyrophyllite–kaolinite–muscovite assemblages; Zone V, argillic alteration mainly comprises kaolinite–illite–montmorillonite and an outermost zone of propylitic (chlorite–epidote–kaolinite–montmorillonite–siderite) assemblages. The alteration assemblages and zonation patterns reflect decreasing acidity and temperature during the lateral flow of hydrothermal fluids from the central silicic cores to the exterior. The Dibaonamugang lithocap exhibits a hypogene origin superimposed by a later supergene environment, and its extension is controlled by structural (fracture and unconformity) and lithological (protolith composition and permeability) factors. Short–wave infrared spectral results, whole–rock and mineral chemistry strongly suggest the presence of a porphyry–high sulfidation epithermal metallogenic system situated beneath and to the southeast of the Dibaonamugang lithocap. These results imply great potential for discovering independent high–sulfidation epithermal Au (Cu) deposits within both the Duolong Ore District and the broader terrestrial volcanic–covered region of the Bangong–Nujiang Metallogenic Belt.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106628"},"PeriodicalIF":3.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891588","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":"Clustering in geo-data science: Navigating uncertainty to select the most reliable method","authors":"Behnam Sadeghi","doi":"10.1016/j.oregeorev.2025.106591","DOIUrl":"10.1016/j.oregeorev.2025.106591","url":null,"abstract":"<div><div>Clustering is a fundamental technique in unsupervised learning that groups data points based on their similarities, enabling the discovery of underlying structures and patterns without the need for labeled examples. In geo-data science, clustering plays a pivotal role in applications such as exploratory data analysis, geochemical anomaly detection, and dimensionality reduction for multivariate data analysis. Mineral exploration, in particular, involves various uncertainties that significantly affect decision-making processes. A key source of such uncertainties arises from the choice of clustering methods and their evaluation metrics. Among the widely used clustering methods, K-Means, K-Medoids, Silhouette and Hierarchical Clustering are prominent, with K-Means being a more popular choice in geosciences. Similarly, evaluation techniques such as Silhouette, Davies-Bouldin, Calinski-Harabasz, Elbow, and Bayesian Information Criterion are employed, with the Elbow method being a frequent favorite in geo-data science. However, questions remain regarding the efficiency and suitability of these methods in different contexts. Should we rely solely on K-Means and Elbow, or should we adopt a more case-specific approach, comparing uncertainties and selecting methods that minimize them? This research provides a critical review of clustering methods and evaluation metrics in geo-data science. By developing the <em>pyClusterWise</em> Python package and using illustrative examples, the importance of tailoring these adjustments to the data and selecting clustering techniques and evaluation metrics based on their associated uncertainties is demonstrated. By doing so, the aim is to reduce overall uncertainty and improve decision-making outcomes in mineral exploration.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106591"},"PeriodicalIF":3.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143844923","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":"Discovery of xenotime-(Yb) and its geological significance in the north Wuyi area, Southeast China","authors":"Shuilong Wang ,&nbsp;Kaixuan Li ,&nbsp;Yanjun Wang ,&nbsp;Dazhao Wang ,&nbsp;Lin Xu ,&nbsp;Shuang Liu ,&nbsp;Longfei Wang ,&nbsp;Cheng-Biao Leng","doi":"10.1016/j.oregeorev.2025.106625","DOIUrl":"10.1016/j.oregeorev.2025.106625","url":null,"abstract":"<div><div>Xenotime-(Yb), a rare phosphate mineral enriched in HREEs, has not been previously reported in China. Based on field investigations and comprehensive petrographic and mineralogical analyses, including optical microscopy, laser Raman spectroscopy, SEM, EPMA, and LA-ICP-MS, xenotime-(Yb) is identified for the first time in quartz-wolframite veins of the Gexianshan granite, located in the North Wuyi area, Jiangxi Province, China. Xenotime-(Yb) occurs as discrete microscale particles (1–10 μm), either enclosed within wolframite or situated in its fissures. Within the isomorphic YbPO₄ –YPO₄ series, Yb/Y atomic ratios range from 0.08 to 1.50, producing distinct gray bands in BSE images. The RE₂O₃ content ranges from 67.1 % to 72.8 % and is dominated by HREEs, particularly Yb and Y. The apfu of Yb in xenotime-(Yb) vary significantly, from 0 to 0.4. Lu and Tm exhibit a positive linear correlation with Yb, while Y and Gd show a negative linear correlation. The compositional characteristics indicate complete isomorphic substitution among Lu, Tm, Y, Ga, and Yb, whereas Dy, Ho, Er, and Yb undergo incomplete substitution. The chemical formula of the Yb-rich end-member particle is (Yb_0.37Y_0.25Lu_0.16Er_0.12Dy_0.09Tm_0.03Ho_0.02Gd_0.01)_∑1.04P_0.97O₄. Raman spectroscopy reveals characteristic peaks for xenotime-(Yb), distinguishing it from xenotime-(Y) by a unique peak at 290 cm⁻¹. The discovery not only represents the first identification of xenotime-(Yb) in Jiangxi Province but also has important implications for the exploration of HREE resources and supports the potential application of YbPO₄ in materials science.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106625"},"PeriodicalIF":3.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847828","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":"Features of the inorganic components of a Middle Jurassic coal from the Haiwan mine, Shenfu mining area, Ordos Basin, northern China: Emphasis on origins of sub-micron and micron-sized quartz","authors":"Niande Shang ,&nbsp;Jingjing Liu ,&nbsp;Shifeng Dai ,&nbsp;Ian T. Graham ,&nbsp;David French ,&nbsp;Qiuchan Han ,&nbsp;Mengda Yao ,&nbsp;Rongkun Jia ,&nbsp;Yan Wang","doi":"10.1016/j.oregeorev.2025.106620","DOIUrl":"10.1016/j.oregeorev.2025.106620","url":null,"abstract":"<div><div>Fine quartz particles released by coal mining and combustion can be detrimental to human health, potentially causing permanent lung damage and even death. Therefore, research on the particle size distribution, modes of occurrence, and formation mechanisms of quartz in coal is essential for guiding safe and efficient coal mining as well as the safe utilization of coal resources. In this study, multiple analytical methods, including X-ray fluorescence, inductively-coupled-plasma − mass spectrometry, quantitative X-ray diffraction, optical microscopy, and scanning electron microscopy, were employed to determine the geochemical and mineralogical features of coal from the Haiwan mine located in the Ordos Basin, China. The Haiwan coal is a bituminous coal with low ash, low sulfur, and high volatile content. The inorganic constituents in the coals were derived from intermediate and felsic rocks of the Yinshan Orogenic Belt, as well as from multiple stages of authigenesis and fluid injections. Notably, quartz constitutes a high proportion of the low-temperature ashes of the coal, with an average proportion of 42.8 %. Authigenic quartz primarily occurs in the form of aggregates of sub-micron to micron-sized particles, typically closely coexisting with kaolinite and boehmite. This mineral assemblage resulted from precipitation of Si-rich solutions leached from the lithologies of the provenance area, along with the dissolution of terrigenous detrital feldspars and desiliconization of kaolinite. Most of the authigenic quartz particles (&lt;10 µm) with sharp edges in the coals, which are small enough to easily enter the respiratory tract, might do harm to lung tissue. Therefore, although the contents of SiO₂ (4.5 %) and quartz (5.41 %) are low on a whole coal basis, prolonged inhalation of these quartz particles may still pose health risks to humans, especially from the combustion products (i.e., coal ash) which contain much higher proportions of quartz.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106620"},"PeriodicalIF":3.2,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850551","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 of the early Cretaceous porphyritic granitoid: New insights from the Hongling skarn polymetallic metallogenesis, NE China","authors":"Meng Dai ,&nbsp;Guangsheng Yan ,&nbsp;Cui Liu ,&nbsp;Yongsheng Li ,&nbsp;Wenbin Jia","doi":"10.1016/j.oregeorev.2025.106599","DOIUrl":"10.1016/j.oregeorev.2025.106599","url":null,"abstract":"<div><div>The Hongling skarn Fe–Pb–Zn deposit is situated in the Lindong district of eastern Inner Mongolia, southern Great Hinggan Range. Previous investigations have established that the metallogenic fluid and ore-forming material at Hongling originated from the magmatic system, with mineralization temporally coinciding with the early Cretaceous granitic emplacement (ca. 142–143 <!--> <!-->Ma). Petrogenetic studies further suggest that the Hongling granitoids share comparable magmatic origins and evolutionary pathways with regional contemporaneous intrusions. In this contribution, we integrate new zircon U-Pb geochronology, whole-rock geochemistry, and Sr-Nd-Hf-S-Pb isotopic analyses of porphyritic granitoids and associated sulfides with existing regional datasets to: (1) constrain the magmatic evolution of Hongling intrusives; (2) discriminate between mineralized and barren intrusion characteristics; and (3) elucidate metallogenic processes. In situ sulfur (δ³⁴S = −2.8 ‰ to +1.1 ‰) and lead (²⁰⁶Pb/²⁰⁴Pb = 18.292 to 18.303) isotopic signatures from ore minerals demonstrate a predominant magmatic derivation..The porphyritic granitoids exhibit transitional Sr-Nd-Hf isotopic compositions ((⁸⁷Sr/⁸⁶Sr)<em>_i</em> = 0.7065–0.7091, <em>ε</em>_Nd(<em>t</em>) = −1.25 to +0.69, and <em>ε</em>_Hf(<em>t</em>) = +0.12 to +8.39), consistent with partial melting of juvenile lower crustal sources. Comparative analysis with regional coeval plutons reveals that the Lindong mineralized intrusions underwent crystal-melt segregation processes, with the Hongling porphyritic phase representing interstitial melts extracted from crystal-rich mush zones.. Subsequent reactivation of these segregated melts facilitated efficient extraction and concentration of ore-forming fluids, ultimately leading to Fe-Pb-Zn mineralization through fluid-rock interaction in skarn systems.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106599"},"PeriodicalIF":3.2,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855125","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":"Characterization of primary geochemical halos for the Hetaoba volcanic-related uranium deposits in Duolun County, Inner Mongolia","authors":"Qiang Wang ,&nbsp;Yong Wang ,&nbsp;Xueqiu Wang ,&nbsp;Zhizhong Cheng ,&nbsp;Xiaojun Jiang ,&nbsp;Hanliang Liu ,&nbsp;Mi Tian ,&nbsp;Dongsheng Wang","doi":"10.1016/j.oregeorev.2025.106611","DOIUrl":"10.1016/j.oregeorev.2025.106611","url":null,"abstract":"<div><div>Primary geochemical halo is a powerful tool for exploring blind deposits. However, primary geochemical halo studies have seldom been conducted on hydrothermal uranium deposits. This study conducted primary geochemical halo studies on the Hetaoba volcanic-related uranium deposit in the Guyuan–Hongshanzi uranium-polymetallic metallogenic belt based on the 780 core samples with 20 elements analyzed from 13 boreholes. Staged factor analysis (SFA) of the centered log-ratio (CLR) transformed data showed that an ore-related elemental association is F1 (U–Mo–As–Pb–Cd–Sb association). However, scatter plots and anomaly maps based on the thresholds determined by the concentration–number (C–N) fractal model showed that the extent of sulfide-rich zones was larger than that of uranium mineralization, and some sulfide-rich zones were accompanied by low uranium content, although uranium mineralization was always accompanied by sulfide enrichment. Furthermore, uranium minerals were distributed along the metal sulfide edges and even encased them, suggesting that uranium mineralization may have occurred later than the sulfide precipitation. Zoning patterns of indicator elements (from top to bottom) for ore bodies at shallow (AZS₁) and greater (AZS₂) depths determined by Gregorian’s method are Bi–Zn–Cd–Mo–Sb–Cs–Pb–Hg–U–Sc–Be–Li–W–Cu–As–Tl–V–Co–Cr–Ni and Cr–Ni–Sc–Be–W–V–Co–Sb–As–Bi–Cu–Pb–Mo–U–Hg–Zn–Cd–Li–Tl–Cs, respectively. These results are significant for mineral exploration. Sulfide-rich zones may provide favorable space and reducing agents for uranium mineralization and can serve as an auxiliary indicator for uranium exploration. More importantly, strong Hg anomalies at relatively greater depths may represent favorable traps for uranium deposition. Consequently, Hg can serve as a near-ore indicator of uranium exploration at relatively greater depths. In addition, AZS₂ front-halo elements may suggest the superposition of two metallogenetic stages and exploration potential in the up-dip of the fault zone.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106611"},"PeriodicalIF":3.2,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143814829","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":"Mineralogical and geochemical investigations of the Li-rich clay strata from Central Yunnan, Southwest China","authors":"Yu Chen ,&nbsp;Hanjie Wen ,&nbsp;Ni Tao ,&nbsp;Fei Xu ,&nbsp;Qin Ye","doi":"10.1016/j.oregeorev.2025.106614","DOIUrl":"10.1016/j.oregeorev.2025.106614","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The recently identified lithium (Li)-rich clay strata in the southwestern Yangtze Block represent a potentially significant global sedimentary Li resource, with estimated Li&lt;sub&gt;2&lt;/sub&gt;O reserves exceeding 2 million tons. However, the genesis and metallogenic process of these Li-rich clay strata remain unclear. This study systematically investigates 251 samples from 18 drill cores of the early Permian Daoshitou Formation in center Yunnan, southwestern Yangtze Block, using inductively coupled plasma mass spectrometry (ICP-MS), X-ray diffractometry (XRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), TESCAN Integrated Mineral Analyser (TIMA), and laser-ablation ICP-MS (LA-ICP-MS) to elucidate the provenance and deposition pattern of Li-rich clay strata. The Li concentration of Li-rich clay strata from the Daoshitou Formation ranges from 2.7 to 6790 ppm, showing a strong correlation with Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, SiO&lt;sub&gt;2&lt;/sub&gt; and A/S, indicating a dominant aluminosilicate affinity. Illite, chlorite, and kaolinite dominate the aluminosilicate minerals in Li-rich clay strata. The strong positive correlation (R&lt;sup&gt;2&lt;/sup&gt; = 0.85) between chlorite and Li concentration indicates that chlorite is the main host mineral for Li, with LA-ICP-MS results showing Li concentration in chlorite up to 12,000 ppm. A high chemical index of alteration (CIA) and the abundant presence of kaolinite, boehmite, and diaspore in the Li-rich clay strata indicate intense supergene weathering. The PAAS-normalized trace elements diagrams and UCC-normalized REE patterns reveal similarities between the Daoshitou Formation’s Li-rich clay strata and the carbonate rocks from the Weining Formation, demonstrating that these carbonate rocks are the primary sources. The weakly alkaline environment created by the weathering of carbonate rocks facilitates the formation of clay minerals, primarily montmorillonite, which is conducive to the adsorption and retention of Li during the weathering stage. However, the presence of Li-rich chlorite in large quantities, an unusual product of supergene weathering, suggests that the Li-rich clay strata underwent significant reformation during the burial stage. TIMA and SEM analyses reveal the distribution characteristics of dissolved elements and minerals suggest this late-stage reformation is related to groundwater influence. The geochemical indicators (Sr/Ba: 0.003 to 1.85, avg. 0.28; Ni/Co: 1.05 to 31.66, avg. 5.99; V/ (V + Ni): 0.42 to 0.99, avg. 0.77) indicate that the depositional environments of the Li-rich clay strata were terrestrial freshwater settings under oxic-suboxic conditions, which might be influenced by both sedimentation and later groundwater reconstruction. Overall, the formation of the Li-rich clay strata appears to be controlled by a combination of weathering-deposition, burial and late reformation. The findings presented in this study provide insights into the formation mechanisms and","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106614"},"PeriodicalIF":3.2,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859617","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}