Journal of African Earth Sciences最新文献

{"title":"Mapping flood hazard in Driouch region (north-eastern of Morocco) using AHP and numerical approaches","authors":"Lamiae El Hadri ,&nbsp;Farid Boushaba ,&nbsp;Mimoun Chourak ,&nbsp;Maelaynayn El Baida","doi":"10.1016/j.jafrearsci.2025.105776","DOIUrl":"10.1016/j.jafrearsci.2025.105776","url":null,"abstract":"<div><div>Driouch City situated in the northeastern of Morocco, has been historically prone to flooding due to its geomorphological and anthropogenic factors. The main objective of this study is to conduct a comparative analysis of the flood hazard in this region using two different approaches. The first approach combined GIS with the multi-criteria decision analysis AHP to create flood hazard maps, using nine static key parameters, which are elevation, slope, flow accumulation, distance from the river, drainage density, runoff, land use, Topographical Wetness Index (TWI), and Normalized Difference Vegetation Index (NDVI). Then, weights are assigned to these factors based on their impact on flooding in the Driouch City. The results indicate that the distance from the river significantly affect areas surrounding the mainstream of Kert basin and its two tributaries. The next step involves comparing the AHP-GIS results with the outputs from the numerical method commonly used as a validation approach for static methods. In this study, it consists of conducting a hydraulic simulation using Iber, a 2D model based on the Saint-Venant equations for flood area distribution. The key input parameters of the simulation are Digital Elevation Model (DEM), land use, runoff and rainfall data. The post-process of the simulation shows how water depths and velocities are distributed along the rivers, noting the high vulnerability to flooding of Oued Kert and Oued Hammam with values exceeding 1m and 1m/s, respectively. By overlaying these two parameters using the GIS, the second flood hazard map is obtained. The comparison of the two resulting maps shows a clear similarity for areas classified as having higher-order flood hazards, which confirms the findings of each other and correlating with historical data; AHP classifying and weighting flood causative factors, and Iber modeling the behavior of the flood. This study concludes the importance of considering the two approaches to assess flood hazards. Most vulnerable areas to sudden floods are residential areas in this case, requiring the redevelopment of watercourses and hydraulic structures and developing a risk prevention plan.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105776"},"PeriodicalIF":2.2,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144696524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic interpretation, structural and property modelling of Cenomanian siliciclastic/carbonates Abu Roash reservoirs in the El Diyur field (Abu Gharadig Basin, NW Desert, Egypt): Implications for reservoir architecture, distribution and evaluation","authors":"Mohamed Fathy ,&nbsp;Amer A. Shehata ,&nbsp;Mohamed Sadoun ,&nbsp;Ramadan Abdelrehim ,&nbsp;Kamal Abdelrahman ,&nbsp;Mohammed S. Fnais ,&nbsp;Mohamed Reda","doi":"10.1016/j.jafrearsci.2025.105772","DOIUrl":"10.1016/j.jafrearsci.2025.105772","url":null,"abstract":"<div><div>This study presents a comprehensive integration of seismic and petrophysical assessment of the Abu Roash “G\" Member in the El Diyur Oil Field, east Abu Gharadig Basin, aiming to characterise reservoir heterogeneity and evaluate hydrocarbon potential in a complex faulted setting. The overall integration of seismic, structural, and petrophysical data was employed to delineate the reservoir's structural configuration, lithological variations, and lateral distribution of reservoir properties. Seismic interpretation revealed a sheet-like geometry with the northward-dipping reflectors intersected by a major east-west trending, south-dipping normal fault (F1) and a minor subsidiary fault (F2). Fault-dependent closures created by F1 were identified as the key structural traps for hydrocarbon accumulation. Petrophysical evaluations highlighted distinct lithological variations across the Abu Roash “G-10,” “G-15,” and “G-20″ zones, with G-10 dominated by reservoir sandstones, G-15 by bioclastic limestone, and G-20 by calcareous sandstone interbedded with siltstone. Key reservoir attributes, including effective porosity, water saturation, and clay volume, exhibited lateral variations influenced by both facies and structural controls. Structural and facies modelling, incorporating fault and horizon reconstruction, underscored the impact of structural configuration on reservoir quality and hydrocarbon distribution. Depositional models suggested deltaic and tidal settings, which significantly influenced porosity and water saturation profiles. The outputs emphasise the critical role of integrated structural-petrophysical modelling in understanding reservoir heterogeneity and hydrocarbon accumulation, providing valuable insights for future exploration and development strategies in the El Diyur Oil Field and similar oil fields.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105772"},"PeriodicalIF":2.2,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomarker fingerprinting of crude oils from Niger Delta depobelts, Nigeria","authors":"Omonigho Khalin Egbo ,&nbsp;Olubunmi Christopher Adeigbe ,&nbsp;Onoriode Esegbue","doi":"10.1016/j.jafrearsci.2025.105768","DOIUrl":"10.1016/j.jafrearsci.2025.105768","url":null,"abstract":"<div><div>Twenty-eight crude oil samples from four depobelts in the Niger Delta Basin were analyzed to evaluate source input, depositional environment, thermal maturity, and post-generation alteration. Analytical methods included gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). Biomarker signatures—oleanane/hopane ratios &gt;0.2, low homohopane indices, dominance of C₂₉ ααα-steranes, and abundant C30 hopanes—indicate contributions from both marine and terrestrial organic matter. Elevated C₂₇ steranes suggest algal input, while the predominance of C₂₉ steranes implies significantly higher plant contributions, characteristic of a deltaic-transitional setting. Sterane isomerization ratios suggest oil generation occurred within the early to peak oil window, while hopane parameters confirm peak maturity. Biomarker parameters, particularly oleanane, sterane/hopane, and isoprenoid/n-alkane ratios, delineate two oil families. Family A exhibits high oleanane/hopane and low sterane/hopane values, pointing to a predominantly oxic, terrigenous source. In contrast, Family B includes oils from mixed sources, with lower oleanane/hopane and variable sterane/hopane ratios. Oil family classification is independent of maturity level, as variations likely reflect differences in source rock burial history and basin evolution rather than thermal stress alone. Total ion chromatograms (TICs) and selected ion monitoring (m/z 191, 217) display no evidence of biodegradation, evaporative fractionation, or water washing in the biomarker assemblage. However, subtle effects of secondary migration or compositional mixing cannot be entirely ruled out. These findings underscore the complexity of hydrocarbon generation and accumulation in the Niger Delta, shaped by variable organic inputs, depositional settings, and post-generative geological processes.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105768"},"PeriodicalIF":2.2,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Organic geochemistry and hydrocarbon generation characteristics of Cretaceous outcrop source rocks from the Nigerian Frontier basins","authors":"Abdulkareem Toyin ,&nbsp;Falilat Omotolani Idris ,&nbsp;Olabisi Adekeye ,&nbsp;Jeremiah Ayok ,&nbsp;N'Guessan Francois De Sales Konan","doi":"10.1016/j.jafrearsci.2025.105766","DOIUrl":"10.1016/j.jafrearsci.2025.105766","url":null,"abstract":"<div><div>The present study integrates organic petrographic and geochemical analyses to determine and compare the nature of organic matter, maceral assemblages, paleodepositional environment, and hydrocarbon generation characteristics of Cretaceous aged outcrop grayish-dark mudstones (claystones and shales), coaly-shale, and coals from some parts of Anambra, Bida and Dahomey Basins. The total organic carbon (TOC) obtained in the studied coals (14.41–53.69 wt%) and mudstones/shales (0.62 and 14.58 wt%) indicate excellent and a wide range (i.e., excellent – fair) of source rocks, respectively. Pyrolysis S2 of the coals revealed excellent source rock generative potentials, while average pyrolysis S2 of the mudstones/shales, (Anambra: 4.04, Bida: 4.43, and Dahomey: 25.86) indicate a wide range of source rock potentials from good-poor, excellent-poor and very good, respectively. The cross plots of HI vs Tmax, and HI vs OI in addition to maceral assemblages indicate types II, II/III, and III organic matter in the Anambra Basin, types II/III and III-IV in the Bida and type II/III in the Dahomey Basin. Vitrinite/huminite reflectance (Ro), in addition to Tmax, and other biomarker maturity parameters indicate immature thermal conditions before the onset of hydrocarbon generation in all the studied samples. The general low reflectance in the samples could be a result of perhydrous in the coals or due to marine influence. Further, similarities in the maceral assemblages in the studied samples suggest that the mudstones/shales were deposited in proximity to the coal beds. The macerals as identified through transmitted and reflected lights indicate that vitrinites/huminites are dominant with liptinites also having significant proportions (liptinite: Anambra: ≤40 %, Bida: ≤23 %, Dahomey: ≤37 %). The high proportions of liptinites (40-23 %) in addition to high hydrogen indices (HI) (&gt;200 mg HC/g TOC) in the studied coals indicate that they could generate liquid hydrocarbons upon attaining appropriate thermal maturity level. Based on vitrinite reflectance values, the coals fall into lignite to sub-bituminous coal ranks. However, despite the low thermal maturity level in source rock from the Dahomey Basin, occurrence of exsudatinite in the sample indicates in-situ generation of petroleum-like substance. Resin-derived biomarkers (i.e., cadalene and retene) in the Dahomey source rock suggest that resinite macerals could be the source of the in-situ generated petroleum-like substance. The findings in the present study will help in making appropriate decisions on further hydrocarbon exploration activities in the Nigerian Frontier Basins and will serve as pointer to where hydrocarbons could be explored for in the basins.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105766"},"PeriodicalIF":2.2,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addendum to Bryers et al. “An integrated stratigraphic framework for the uppermost Jurassic to Lower Cretaceous interval of the Essaouira-Agadir Basin (Moroccan Atlantic margin) based on ammonites, calcareous nannofossils and calpionellids” [J. Afric. Earth Sci. 216]","authors":"Camille Frau ,&nbsp;Antoine Pictet ,&nbsp;Jonathan Redfern","doi":"10.1016/j.jafrearsci.2025.105735","DOIUrl":"10.1016/j.jafrearsci.2025.105735","url":null,"abstract":"","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105735"},"PeriodicalIF":2.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144663618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physicochemical characterization and quality assessment of groundwater around the Twangiza gold mine (Eastern D.R. Congo)","authors":"Mukungilwa Myango ,&nbsp;Lefranc Basima ,&nbsp;Kavatsurwa Muyisa ,&nbsp;Isaac Chungachako ,&nbsp;Patient Zamukulu ,&nbsp;Lina Aleke ,&nbsp;Muhigwa Bahananga","doi":"10.1016/j.jafrearsci.2025.105767","DOIUrl":"10.1016/j.jafrearsci.2025.105767","url":null,"abstract":"<div><div>The present study focuses on groundwater around the Twangiza gold mine, which serve as a source of drinking water for the local population, with the aim of characterizing it based on its physicochemical properties. A total of 13 water samples were collected for analysis of physicochemical characteristics (pH, TDS, EC, TSS, major cations and anions), using conventional analytical methods. The results indicated acidic to neutral and ranged from 4.5 to 7.1, with 76.9 % acidic (pH 4–6.5), below WHO and EU permissible limits. The hydrochemical facies of groundwater revealed Mg-Ca-SO₄ water types in the vicinities of the mine, indicating sulphate imprint related to the dissolution of gold bearing sulphides, and Ca-Mg-HCO₃ types downstream the mine, more associated with carbonate minerals. Multivariate statistical analysis grouped groundwater based on similarities of physicochemical parameters and indicated the parts of geogenic process and anthropogenic activities in the mineralization. Water-rock interactions involved mainly silicate weathering and indicated the role of sulphide dissolution in the surrounding areas close to the mine. The sodium adsorption rate classified the water as excellent to good, with an overall low alkalizing power, which makes the water suitable for irrigation. The Water Quality Index (WQI) indicated that local groundwater quality ranged from excellent to good across most stations, with the exception of one station within the active mine classified as poor. These findings are helpful for the understanding of groundwater mineralization processes and would assist in the sustainable use of groundwater.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105767"},"PeriodicalIF":2.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144580451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated sequence stratigraphic and petrophysical analyses to evaluate the reservoir potential of the Early Miocene (Burdigalian) Rudeis Formation in Rabeh-East Field, Gulf of Suez Basin, Egypt","authors":"Mohamed M. Elhossainy ,&nbsp;Abdou Farrag ,&nbsp;Mohammad Abdelfattah Sarhan ,&nbsp;Abdelhamid M. Salman ,&nbsp;Alaa Salem","doi":"10.1016/j.jafrearsci.2025.105756","DOIUrl":"10.1016/j.jafrearsci.2025.105756","url":null,"abstract":"<div><div>The Rudeis Formation plays a pivotal role in hydrocarbon exploration within the Gulf of Suez, serving as one of the primary reservoir targets in the region. The principal objective of this study is to integrate high-resolution sequence stratigraphic interpretation with detailed petrophysical analysis to better understand the depositional architecture and reservoir potential of the Lower Miocene Rudeis Formation in the Rabeh-East Field. The dataset utilized in this research includes a combination of wireline logs and seismic profiles from four wells (RE-11, RE-22, TANAN-1, and TAWOOS-1) supplemented by a comprehensive biostratigraphic report prepared for well RE-22. A promising hydrocarbon zone occurs between 4560 and 4632 ft (1389.9 - 1411.8 m), characterized by sandy limestone and calcareous sandstone, with petrophysical parameters: total porosity (Φ_T) of 19 %, effective porosity (Φ_E) of 13 %, water saturation (S_W) of 48 %, and bulk volume of water (BVW) of 9 %. Biostratigraphic analysis identified five planktonic foraminiferal zones (N6/5, N6b, N6c, N7, N8a) and two calcareous nannofossil zones (NN3, NN4), assigning the Rudeis Formation to the Early Miocene (Burdigalian). This zonation allows the succession to be divided into three third-order depositional sequences (DS1–DS3), bounded by four sequence boundaries (SB1–SB4). Each depositional sequence includes transgressive and highstand systems tracts, reflecting relative sea-level variations linked to tectonic and/or eustatic changes. The analysis indicates that the potential reservoir zone was deposited during a transgressive systems tract, marked by the influx of sandy facies during a sea-level rise. Considering all these variables, our findings revealed that the study area's prospective zone was created during the TST with a noticeable invasion of sandy facies during the overall rise in sea level position.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105756"},"PeriodicalIF":2.2,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ground fissures in the central Ethiopian Rift: insights on distribution, genesis and hazard","authors":"E. Vittori ,&nbsp;L. Puzzilli ,&nbsp;G. Delmonaco ,&nbsp;F. Traversa ,&nbsp;V. Ruscito ,&nbsp;Y. Bekele Reba ,&nbsp;J. Satkūnas ,&nbsp;S. Diop","doi":"10.1016/j.jafrearsci.2025.105746","DOIUrl":"10.1016/j.jafrearsci.2025.105746","url":null,"abstract":"<div><div>Ground fissuring is an endemic hazard along the East African Rift, rather common in the volcanic lacustrine deposits of Ethiopia and Kenya. Fissures reach lengths of kilometers and widths of several meters, menacing villages and infrastructures, locally taking the shape of coalescing holes. In this study, the phenomenon has been mapped over the Central Main Ethiopian Rift (CMER), based on field observation and remotely sensed images. Geophysical investigations (geoelectrical and seismic profiles) at two sites (Ziway and Muleti), have provided informative imaging of the underground across recent ruptures. No premonitory ground deformation has ever been reported before the opening of the fissures, whose strike corresponds to that of the widespread system of Late Quaternary faulting inside the Rift. However, while a structural control seems well established, a genetic correspondence of the two phenomena, as observed to the north in the NMER or locally in the western flank of the rift, cannot be proven. As well, no direct link with seismicity does exist. Heavy rains appear to trigger such linear collapses, as in 2016, but again a biunivocal relationship is not yet verified. Thus, this local source of serious hazard remains elusive and unpredictable, unless widespread, and expensive, geophysical and borehole investigations are carried out, possibly supported by high resolution remotely-sensed DinSAR monitoring, still to be proven effective though.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105746"},"PeriodicalIF":2.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144563154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Source rock characterizations of the Devonian to Permian strata in the Persian Gulf Basin, SW Iran","authors":"Ebrahim Sfidari ,&nbsp;Mohammad Sharifi ,&nbsp;Khaled Maroufi ,&nbsp;Seyed Mohamad Zamanzadeh ,&nbsp;Javad Amraie ,&nbsp;Houshang Mehrabi ,&nbsp;Amalia Spina","doi":"10.1016/j.jafrearsci.2025.105755","DOIUrl":"10.1016/j.jafrearsci.2025.105755","url":null,"abstract":"<div><div>The Devonian to lower-middle Permian siliciclastic strata (Zakeen and Faraghan formations) of the South Pars supergiant gas field (Persian Gulf offshore) were geochemically examined to evaluate their petroleum potential. The study was conducted on the deepest appraisal well in the Iranian sector of the Persian Gulf, using an integrated approach combining Rock-Eval pyrolysis and optical kerogen analyses (Vitrinite Reflectance-VR, Spore Color Index-SCI, Palynomorph Darkness Index-PDI, and palynofacies analyses), along with one-dimensional burial history reconstruction and thermal modeling.</div><div>Generally, the low Total Organic Carbon (TOC) content in most parts of the studied formations categorizes them as poor source rocks. However, the geochemical results identified a new source rock interval, Zone-A, with high hydrocarbon generation potential. This interval is introduced as a new gas-prone prospective horizon within the Persian Gulf, deposited through a deltaic to relatively marine suboxic-anoxic environment.</div><div>Our findings suggest that Zone-A has been producing hydrocarbons since the late Eocene, indicating additional undiscovered reserves in the region. This research highlights the significance of further exploration and resource assessment in the area.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105755"},"PeriodicalIF":2.2,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144604282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geology, fluid inclusions, sulfur isotopes, and Rare Earth Element signatures of the Ain Mimoun barite vein-type ore-deposit, Northeastern Algeria","authors":"Imene Benhammoud ,&nbsp;Abdelhak Boutaleb ,&nbsp;Omar Haddouche ,&nbsp;Maria Boni ,&nbsp;Nicola Mondillo","doi":"10.1016/j.jafrearsci.2025.105754","DOIUrl":"10.1016/j.jafrearsci.2025.105754","url":null,"abstract":"<div><div>The barite-vein type of Aïn Mimoun ore-deposit, located in the Saharan Atlas (North-eastern Algeria), is hosted in Albian-Aptian carbonates rocks, and controlled by NE-SW and E-W trending-faults. The vein mineralization mainly consists of barite, associated with galena, sphalerite, grey copper, chalcopyrite, and pyrite. Microthermometric analyses of fluid inclusions indicate moderate to high temperatures (∼105 °C–∼185 °C) and high salinities (20–25 % NaCl equiv.), with eutectic temperatures suggesting H₂O-NaCl-CaCl₂ brines. The presence of Na⁺ and Ca²⁺ in the solutions suggests interaction of the mineralizing fluids with the carbonate-hosted rocks and Triassic formations. The δ³⁴S values of barite (15.7 ‰–26.6 ‰) indicate a sedimentary origin of sulfur, probably involving thermochemical sulfate reduction (TSR) processes. Two isotopic groups are distinguished: white barite associated with sulfides (15.7–17.4 ‰), reflecting sedimentary sulfates, and translucent barite (21.4–26.6 ‰), suggesting prolonged interaction with evaporites. Chondrite-normalized rare earth element (REE) spectra reveal an enrichment in light rare earth elements (LREE), negative cerium anomalies (Ce/La: 0.10–0.81), and positive europium anomalies (35.52–188.62 ppm; Eu/Eu∗: 54.71–88.14), characteristic of hydrothermal deposits created in oxidizing conditions.</div><div>These data suggest a hydrothermal epigenetic origin for the barite-vein type of Aïn Mimoun ore-deposit, classified as Mississippi Valley-Type (MVT). The mineralizing fluids were deep basinal brines migrating along fault zones, interacting with Cretaceous carbonate-hosted rocks and Triassic evaporites, contributing to the barite precipitation processes.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105754"},"PeriodicalIF":2.2,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144563156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}