Journal of Geochemical Exploration最新文献

{"title":"Hydraulic fracturing-induced gold remobilization: Pyrite geochemical and sulfur isotopic insights from the Liuan lode gold deposit, South China","authors":"Xu Wang ,&nbsp;Yu Zhang ,&nbsp;Zebin Tang ,&nbsp;Yongjun Shao ,&nbsp;Bing Xiao ,&nbsp;Shuling Song ,&nbsp;Xingting Sun ,&nbsp;Hongtao Zhao ,&nbsp;Lianjie Zhao","doi":"10.1016/j.gexplo.2026.107994","DOIUrl":"10.1016/j.gexplo.2026.107994","url":null,"abstract":"<div><div>The coupled dissolution-reprecipitation (CDR) process is critical for gold remobilization and re-enrichment within global gold mineralization systems, and its driving mechanism warrants further investigation. The Liuan lode gold deposit in the Dayaoshan district (South China) features multiple generations of pyrite, including Py1 (pre-ore stage), Py2 (including Py2c and Py2r) and Py3 (ore stage), and Py4 (post-ore stage). Py2c is As-Cu-Pb-Ag-Au-rich (initial gold enrichment), suggestive of fluid boiling during its formation, corroborated by low δ³⁴S values (avg. −3.83‰) and hydrothermal breccias. In contrast, Py2r is depleted in these elements, indicative of non-boiling conditions, further supported by heavier δ³⁴S values (avg. −2.53‰). Several pieces of evidence, including sharp reaction fronts and As-Au contents differences between Py2c and Py3, and Py2c remnants and mineral inclusions (chalcopyrite, galena, and native gold) within Py3, indicate the CDR process, during which Au in Py2c was remobilized and reprecipitated as native gold. The CDR process is triggered by oxidation of the mineralizing fluids, consistent with the decreasing δ³⁴S values from Py2r to Py3. Combined with higher Co-Ni concentrations in Py3 (similar to Py2c) relative to Py2r, we infer that fluid oxidation is associated with hydraulic fracturing restart. Multiple sulfur isotopes (δ³⁴S: −4.92 to 0.45‰; Δ³³S: −0.05 ± 0.10‰) and low Co-Ni and high Se contents of pyrite suggest a magmatic fluid origin from a possible concealed intrusion. This study underscores magmatic-hydrothermal contributions in forming lode gold deposits in Dayaoshan, and highlights the importance of pressure-driven hydrothermal processes in initial gold precipitation, remobilization, and reprecipitation within gold deposits.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"284 ","pages":"Article 107994"},"PeriodicalIF":3.3,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102408","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":"Timing and genesis of gold mineralization in the Kibaran Metallogenic Province, D.R. Congo: Constraints from zircon UPb geochronology, trace element chemistry, and LuHf isotopes","authors":"Rub'son Heritier N'nahano ,&nbsp;Huan Li ,&nbsp;Mohamed Faisal ,&nbsp;Annan Guan ,&nbsp;Aye Pyae Phyo ,&nbsp;Moise Luemba ,&nbsp;Wenbo Sun ,&nbsp;Charles Nzolang ,&nbsp;Donat Kampata ,&nbsp;Raphael Matamba","doi":"10.1016/j.gexplo.2026.107972","DOIUrl":"10.1016/j.gexplo.2026.107972","url":null,"abstract":"<div><div>The Kibaran Metallogenic Province represents a world-class metallogenic system, hosting a diverse array of metal deposits, including significant gold mineralization. Despite its economic importance, the genesis and metallogenic evolution of gold mineralization in this region remain poorly understood. This knowledge gap is primarily due to the absence of comprehensive studies that can provide a coherent genetic model for its formation, making it challenging to contextualize the Kibaran gold deposits within the broader framework of global gold occurrences. In this study, we present new U<img>Pb geochronology, trace element chemistry, and Lu<img>Hf isotopic data from zircons extracted from mafic and intermediate-felsic, and sedimentary rocks to elucidate the geodynamic processes and emplacement mechanisms of gold mineralization in the metallogenic province. Our zircon U<img>Pb data reveal two major episodes of gold mineralization: (a) an early Mesoproterozoic event ~1415 Ma associated with the end of Eburnean orogeny, marked by a rift-related magmatic system and dolerite dykes emplacement at Misisi gold field, and (b) a mid-Paleozoic event (~468-333 Ma) linked to the end of Pan-African orogeny, characterized by sedimentation at Misisi and diorite and feldspar porphyry intrusions at Twangiza. Lu<img>Hf isotopic signatures indicate that both magmatic episodes resulted from partial melting of the older Congo-Ruzizian basement, with juvenile crustal input. Zircon trace element compositions suggest that gold mineralization was generated under high-temperature, oxidizing fluid conditions, with magma migrating from the lower to the upper crust, where it interacted with reduced fluids from carbonaceous country rocks, facilitating gold deposition. These findings suggest that the gold mineralization events in the Kibaran Metallogenic Province coincided with failed rift systems during the breakup of the Columbia and Gondwana supercontinents. This study provides new insights into the temporal relationships between supercontinent cycles and gold mineralization events in the Democratic Republic of Congo.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107972"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979852","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":"Magnetite texture and composition in the Makeng Fe skarn deposit, Southeastern China","authors":"Jiaxing Hu ,&nbsp;Jing Xu ,&nbsp;Wei Zheng ,&nbsp;Taiping Zhao ,&nbsp;Huochun Shen ,&nbsp;Bo Xing","doi":"10.1016/j.gexplo.2026.107975","DOIUrl":"10.1016/j.gexplo.2026.107975","url":null,"abstract":"<div><div>Magnetite is the most important ore mineral in Fe skarn deposits. Its textural and compositional signatures effectively indicate the ore-forming environment and can fingerprint mineralization processes. The Makeng deposit is the largest Fe skarn deposit in southeastern China, which is a case study for constraining the mineralization process by using textures and composition of magnetite. Four generations of magnetite (MagI to MagIV) are distinguished in this deposit. The MagI and MagIII both show similar oscillatory zoning with abundant micro-nano silicate inclusions, however, the texture relationship indicates that MagI formed earlier than MagIII and they have different compositions as well as inclusion density. MagII contains randomly distributed pores and coarsened inclusions. In contrast, MagIV is clean and free of inclusions and pores. All four types of magnetite are of hydrothermal origin. However, they crystallized in distinct stages within different conditions. The MagI crystallized from a relatively high-temperature and supersaturated fluid enriched in Fe, Si, Ca, and Al. The formation of MagII is due to dissolution-reprecipitation of MagI. The MagIII was likely formed by continuous magmatic-hydrothermal pulse. However, the relatively low contents of Si, Al, and Ca lead to lower density of silicate inclusions compared to MagI. Finally, the MagIV formed under relatively low temperature and high oxygen fugacity conditions, and the low concentrations of Si, Al, Ca, and Mg within the fluids prevented the development of inclusions. Abundant silicate inclusions in Makeng magnetite indicate that the influence of inclusions on the occurrence of trace elements cannot be overlooked, which highlights the importance of petrographic study for understanding the trace element occurrence. Magnetite from Makeng also shows significant enrichment of Ga (average 45 ppm) and Co (average 30 ppm). Ga enrichment might primarily have been controlled by temperature and oxygen fugacity, whereas Co enrichment is constrained by other factors.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107975"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979958","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":"Arsenate adsorption onto hydrous ferric oxide: Insights from triple layer surface complexation modeling","authors":"Hafsa Nazir ,&nbsp;Raheena Moozhikkal ,&nbsp;Bhawna Thakur ,&nbsp;Shray Pathak ,&nbsp;Pushpendra P. Singh","doi":"10.1016/j.gexplo.2026.107992","DOIUrl":"10.1016/j.gexplo.2026.107992","url":null,"abstract":"<div><div>This study investigates arsenate [As(V)] adsorption dynamics along soil depth profiles in natural soils from Gurukhwind village, Tarn Taran district, Punjab, using batch adsorption experiments in an arsenic (As) affected region. Kinetic experiments showed rapid As(V) adsorption within the first 4 h, reaching equilibrium at 12 h across all soil layers. As(V) adsorption was substantially higher in surface soil layers than in bottom layers, largely due to variations in surface area, organic matter content, pH, and mineralogical components such as hydrous ferric oxide (HFO). Adsorption decreased with increasing pH, with maximum uptake occurring under acidic conditions due to enhanced electrostatic forces of attraction between protonated surface sites and negatively charged As(V) species. The pseudo-first-order (PFO) model best described the kinetic data, while equilibrium data followed the Langmuir isotherm, indicating monolayer adsorption, with R² values exceeding 0.9 across all soil layers. The 2-pK Triple Layer Model (TLM) successfully simulated the pH-edge and isotherm trends for As(V) adsorption on HFO, suggesting the formation of dominant inner-sphere complexes = Fe(H₂AsO₄), =Fe(HAsO₄)⁻ and = Fe(AsO₄)²⁻ along with minor contribution from outer-sphere complexes FeOH₂⁺_ H₂AsO₄⁻ and FeOH₂⁺ _ HAsO₄²⁻<em>.</em> The good agreement between modeled and experimental data was supported by reasonable RMSE values for isotherms and pH-edge data. The combined findings underscore the importance of iron (Fe) oxide rich surface horizons in controlling As mobility, with direct implications for the development of site specific management and mitigation strategies in As affected regions.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107992"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078896","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":"Environmental and circular economy-based characterisation of abandoned mine wastes in the Odiel River basin (southwestern Spain)","authors":"David Caro-Moreno ,&nbsp;Francisco Abel Jiménez-Cantizano ,&nbsp;Lola Yesares ,&nbsp;José María González-Jiménez","doi":"10.1016/j.gexplo.2026.107988","DOIUrl":"10.1016/j.gexplo.2026.107988","url":null,"abstract":"<div><div>The Odiel River basin (southwestern Spain) is severely affected by acid mine drainage resulting from a long history of intensive mining, particularly during the 19th and 20th centuries. This legacy has left numerous abandoned mine wastes scattered across the basin, contributing to widespread contamination of the river system. Many of these materials also contain economically relevant concentrations of critical and high-tech metals. This study evaluates the acid-generation potential of several waste types and provides a preliminary assessment of their suitability for metal recovery. A detailed characterisation was conducted on wastes from 24 abandoned sites, including measurements of surface area, volume, tonnage, acid-generation capacity (via acid–base accounting), and pseudo-total concentrations of 33 elements. Crude sulphide ores, despite their limited volume, exhibit the highest acid generation potential, whereas mixed wastes in dumps pose the greatest environmental risk due to their large tonnage. Roasted pyrite wastes and roasted pyrite ashes are highly enriched in valuable metals, with a preliminary estimated gross recovery value of up to 0.9 billion USD based on the combined contents of the analysed elements. Environmental desulphurisation is proposed as an effective strategy to reduce acidity and enable metal recovery, with the potential to eliminate approximately 80% of the total acidity associated with the studied wastes. Overall, the findings support integrated remediation and resource-recovery approaches consistent with circular-economy principles.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107988"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979851","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":"Geochemical evolution of the mineralizing fluids at the Tenke-Fungurume Mining District (DR Congo): Insights from microthermometry, crush-leach, and LA-ICP-MS analyses of fluid inclusions","authors":"Jessica Torres ,&nbsp;Pascal Mambwe ,&nbsp;Philippe Muchez","doi":"10.1016/j.gexplo.2026.107971","DOIUrl":"10.1016/j.gexplo.2026.107971","url":null,"abstract":"<div><div>The Tenke-Fungurume mining district, located in the northern part of the Katanga Copperbelt, DR Congo, hosts numerous carbonate-quartz veins that demonstrate the pre-, <em>syn</em>-, and post-folding events related to the Lufilian Orogeny. Microthermometric and geochemical analyses of their contained fluid inclusions were performed to understand the fluid evolution throughout those phases. Primary fluid inclusions record a large range of T_h (149–372 °C) and salinity (37.1–59.9 wt% NaCl + KCl eq.) for all phases, which cannot be used to differentiate between successive mineralizing events. Laser ablation ICP-MS and crush-leach analysis invariably point to fluids originating from the progressive evaporation of seawater. Fluid chemistry was strongly controlled by intense fluid-rock interactions at high temperatures. All dolomite samples show major recrystallization patterns and generations, which testify to fluid flow events that likely affected the whole Katanga basin. High contents of Cu, Co, Ba, Zn, and Pb relative to Na were measured in primary fluid inclusions of all phases, suggesting mineralization was not restricted to discrete or unique events, but rather that the same hydrothermal ore-forming system operated over a long period during basin evolution and deformation.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107971"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979956","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":"A novel “green” sample preparation method for portable X-ray fluorescence (pXRF) geochemistry of unconsolidated sediments as compared to traditional laboratory protocols","authors":"Ross D. Knight,&nbsp;Bruce A. Kjarsgaard","doi":"10.1016/j.gexplo.2025.107968","DOIUrl":"10.1016/j.gexplo.2025.107968","url":null,"abstract":"<div><div>Successful geochemical analyses utilizing in-field portable X-ray fluorescence spectrometry (pXRF) of unconsolidated glacial derived sediments is dependent on sample preparation to provide a consistent representation of the material being analysed. This study evaluates a novel, eco-friendly, “green” sample preparation technique – granular convection - for in-field pXRF spectrometry to acquire on-site real time geochemistry. This method eliminates the use of sieves and minimizes valuable in camp resources (time, solvents, brushes, air compressors etc.) by separating grain sizes through simple agitation of dried samples prior to analyses.</div><div>Results from granular convection sample preparation followed by pXRF spectrometry are compared with laboratory sample preparation to &lt;0.063 mm size fraction followed by ICP-ES/MS for aqua regia, 4-acid, and lithium metaborate/tetraborate fusion digestions for a ∼33,500 km² remote region of northern Canada. Comparative data are presented as x-y bivariate plots and interpolated regional spatial distribution maps to highlight similarities and differences between sample preparation and analytical methods. This comparison demonstrates that although in-field sample preparation by granular convection and subsequent pXRF analyses are not always as accurate as laboratory preparation methods, they are comparative on the regional scale shown in this paper. This approach enhances analytical efficiency, reduces resource consumption, and supports cost-effective mineral exploration and/or an environmental sampling program.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107968"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979957","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":"Geochemical evaluation of resource potential in mafic-ultramafic intrusions: A case study on Ni and Co in the Hongshishan complex of Gansu Province, China","authors":"Zhendong Lv ,&nbsp;Ye Liu ,&nbsp;Qingjie Gong ,&nbsp;Haiyun Chen ,&nbsp;Taotao Yan","doi":"10.1016/j.gexplo.2026.107986","DOIUrl":"10.1016/j.gexplo.2026.107986","url":null,"abstract":"<div><div>Mafic-ultramafic intrusions are closely associated with Ni<img>Co mineralization. Geochemical evaluation of resource potential in mafic-ultramafic intrusions plays a crucial role in guiding Ni<img>Co mineral exploration. The Ni<img>Co prospecting potential in the Hongshishan mafic-ultramafic complex in Gansu Province is under consideration. A detailed geochemical exploration of the stream sediment-soil-rock system in the Hongshishan area was conducted in this study to illustrate the method for geochemical evaluation of Ni and Co resource potential in mafic-ultramafic intrusions. The stream sediments originated from the regional geochemical survey with a scale of 1:200,000, the soils were from the detailed geochemical survey with a scale of 1:50,000, and the rocks were collected from the Hongshishan complex and its surrounding strata. For elemental concentrations, a nineteen levels' fixed-value method of concentrations (19LsFC) is used to classify Ni and Co concentrations. In the Hongshishan complex, Ni and Co concentration levels are consistently above the 10th level, even reaching the cut-off grade at the 19th level. Furthermore, their concentrations increase systematically from stream sediments through soils to rocks. For elemental anomalies, a seven levels' classification method of anomalies (7LsAn) is adopted to classify geochemical anomalies of Ni and Co. The anomaly levels of Ni and Co are all higher than the 3rd level and even up to the 7th level (or the cut-off grade level), and increase from stream sediments to rocks in the Hongshishan complex region. Here the 19LsFC on Co is presented on eighteen fixed values, including the analytical detection limit, the median value of surface soils in China, the cut-off grade, etc. The 19LsFC is valid to compare elemental concentrations between different elements and samples in a uniform “ruler”. The 7LsAn is constructed on two “nails” (the background value and the cut-off grade value) for a single sample and is also useful for comparing different elements and samples. The illustration in the Hongshishan area provides a new geochemical approach for Ni<img>Co resource exploration in mafic-ultramafic intrusions.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107986"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979955","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":"VNIR spectral signatures of chromium-substituted goethite and hematite in Sukinda ultramafic laterites, India: From mineral spectra to spaceborne hyperspectral mapping","authors":"Raphael J. Baumgartner ,&nbsp;Heta M. Lampinen ,&nbsp;Yoram Teitler ,&nbsp;Mario Iglesias-Martinez ,&nbsp;Erick Ramanaidou ,&nbsp;Belinda Godel ,&nbsp;Carsten Laukamp ,&nbsp;Anwesha Nasreen ,&nbsp;Sisir K. Mondal ,&nbsp;Helen Powell","doi":"10.1016/j.gexplo.2025.107970","DOIUrl":"10.1016/j.gexplo.2025.107970","url":null,"abstract":"<div><div>This study demonstrates, to our knowledge, the first spaceborne hyperspectral attribution of minor-element substitution in natural iron (oxyhydr)oxides, whereby incorporation of Cr into goethite and hematite produces diagnostic spectral features in the visible to near-infrared (VNIR) wavelength region. Hyperspectral satellite imagery of ferruginous laterite over chromitite-bearing ultramafic rocks at Sukinda (Odisha, India) was integrated with field sampling, petrographic and mineralogical characterization, bulk and mineral-scale chemical analyses, and laboratory VNIR spectroscopy supported by Cr-doped synthetic reference materials. Across the weathering profile—from chromitite–serpentinite bedrock upward through saprock–saprolite to ferruginous laterite and duricrust/ferricrete—Cr is strongly partitioned into goethite and hematite, locally reaching concentrations of up to 20 wt% within goethite. Laboratory reflectance spectra of natural and synthetic goethite and hematite materials reveal Cr-induced modifications to a key crystal-field absorption feature (CFA₁) in the ~650–700 nm range, with the band minimum shifting to longer wavelengths as Cr concentration increases. This behaviour supports a two-component model comprising CFA₁-Fe (~655 nm) and CFA₁-Cr (~700 nm), attributed to ligand-field transitions of octahedrally coordinated Fe³⁺ and Cr³⁺, respectively. Equivalent CFA₁ shifts in PRISMA hyperspectral imagery delineate Cr-rich alteration domains, with continuum-subtracted CFA₁ minima ≥685 nm enabling robust discrimination of Cr substitution in iron (oxyhydr)oxides at low, single-digit concentrations (~2 wt% Cr, approximated from synthetic reference materials). These results demonstrate that spaceborne hyperspectral data can resolve Cr enrichment in ferruginous laterites, enabling new applications in mineral exploration, environmental monitoring, and potentially planetary surface investigations.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107970"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979961","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 sources and evolution in the As (±Sb) epithermal Matra deposit (Alpine Corsica, France): Constraints from fluid inclusions, gas compositions, and stable isotopes (C–O)","authors":"Danis Ionut Filimon ,&nbsp;John A. Groff ,&nbsp;Paolo Fulignati ,&nbsp;Maria Di Rosa","doi":"10.1016/j.gexplo.2026.107996","DOIUrl":"10.1016/j.gexplo.2026.107996","url":null,"abstract":"<div><div>The Matra mine (Alpine Corsica, France) was a historic source of high-grade arsenic ores composed of realgar ± stibnite. Prior to this study, no fluid inclusion or stable isotope data were available to characterize hydrothermal fluids and develop a genetic model. As the mineralization is coarse-grained and paragenetic relationships are evident, it is possible to generate data for representative samples that span the mineralizing event. Therefore, samples of quartz, carbonate, and realgar were studied to determine the origin(s) and evolution of mineralizing fluids. The mineralization occurs in a post–Alpine brittle structure formed during Early Miocene extensional tectonism. After the failure of host rocks due to fault movement, boiling of a high-temperature (∼290 °C) and moderately saline (∼9 wt% NaCl_equiv.) hydrothermal solution occurred during pre–ore stage quartz mineralization at depth of 500–800 m. Continued movement along the Matra Fault created permeable zones that allowed mixing between magmatic, evolved meteoric, and meteoric fluids. An increasing influx of meteoric water is indicated by gas-poor fluid inclusions in realgar having T_h ∼ 60 °C and salinities ∼0.5 wt% NaCl_equiv. Fluid mixing is recorded by the distribution of gas data in CO₂/CH₄ vs. N₂/Ar and N₂–Ar–He diagrams combined with C–O isotope data. The magmatic signature could be related to the early opening of the Tyrrhenian Sea, accompanied by crustal thinning and asthenospheric upwelling. In this framework, major tectonic structure of the Matra area could have focused heat flow and deep gases from the mantle to create a dynamic hydrothermal system.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"283 ","pages":"Article 107996"},"PeriodicalIF":3.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078894","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}