Journal of African Earth Sciences最新文献

{"title":"Hydrochemistry and pollution assessment of groundwater in the Dodoma: Implications of indices and multivariate statistics","authors":"Uwezo Frank Mao ,&nbsp;Benatus Norbert Mvile ,&nbsp;Mahamuda Abu ,&nbsp;Emmanuel Sulungu","doi":"10.1016/j.jafrearsci.2025.105974","DOIUrl":"10.1016/j.jafrearsci.2025.105974","url":null,"abstract":"<div><div>Groundwater is the primary source of freshwater in arid and semi-arid regions such as Dodoma, Tanzania, where surface water is scarce. This study assessed the hydrochemical characteristics and pollution status of groundwater in the Dodoma region using water quality indices and multivariate statistical approaches. Thirty-five groundwater samples were collected from boreholes distributed across different geological and land-use settings. Laboratory analyses revealed that the groundwater is generally alkaline (pH 5.8–8.2) with total dissolved solids (TDS) ranging from 135 mg/L to 1780 mg/L and electrical conductivity (EC) between 210 μS/cm and 2740 μS/cm. The dominant cations and anions followed the order Na⁺ &gt; Ca²⁺ &gt; Mg²⁺ &gt; K⁺ and Cl⁻ &gt; SO₄²⁻ &gt; HCO₃⁻ &gt; NO₃⁻, respectively. Piper and base-exchange plots classified the groundwater as mainly of the Cl(SO₄)–Na and Na⁺–SO₄^2- types, indicating mineralization dominated by rock–water interaction and evaporation. The Pollution Index of Groundwater (PIG) classified 74.3 % of samples as insignificantly polluted, 17.1 % as low pollution, and 8.6 % as moderate pollution, while the Percentage Pollution Index (PPI) indicated that contamination was primarily anthropogenic. Water Quality Index (WQI) values ranged from 42 to 255, showing that 61.2 % of samples were of poor to very poor quality for drinking. Irrigation suitability assessment showed that 97.1 % of samples were suitable for salt-tolerant crops based on the permeability index and salinity hazard classification. Overall, groundwater mineralization in Dodoma is controlled by both geogenic and anthropogenic processes, emphasizing the need for regular monitoring and mitigation of human-induced contamination.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105974"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787920","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":"Weathering processes and the role of combined chlorite-dolomite as main neutralizing agents of acidic fluids in the Cu(-Pb-Zn-Ag) Bou Skour supergene deposit (Eastern Anti-Atlas, Morocco)","authors":"Julien Poot ,&nbsp;Remi Stanus ,&nbsp;Mohammed EL Azmi ,&nbsp;Augustin Dekoninck ,&nbsp;Lhou Maacha ,&nbsp;Gaëtan Rochez ,&nbsp;Mohammed Bouabdellah ,&nbsp;Johan Yans","doi":"10.1016/j.jafrearsci.2025.105981","DOIUrl":"10.1016/j.jafrearsci.2025.105981","url":null,"abstract":"<div><div>The Cu(-Pb-Zn-Ag) Bou Skour deposit shows the distinctive feature of having its primary mineralization (hydrothermal events) associated with veins of chlorite, dolomite and quartz in Cryogenian and Ediacaran magmatic rocks. The deposit underwent weathering, leading to the oxidation of primary sulfides, formation/neutralization of acidic fluids, and the neoformation of secondary minerals, including carbonates, silicates, and arsenates. Bou Skour deposit shows a quite unusual neutralization process of acidic fluids occurring mainly within/around the chlorite and/or dolomite veins containing primary mineralization. Chlorite, rarely considered as a dominant neutralizing agent, plays a significant role in the formation of secondary minerals in Bou Skour. The dual neutralization (chlorite and dolomite), combined with the diversity of primary assemblages and the vein-associated fractures, strongly influence secondary mineralization patterns and sequences, leading to restricted oxidized zones where different parts of weathering profile merge and overlap. Understanding these mechanisms is essential for unraveling the mineralogical evolution of the deposit and estimates its economic potential.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105981"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837065","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":"Evolution of the Suhum Basin of the Rhyacian Birimian terrane in Ghana: Insight from paraschist and orthoamphibolite","authors":"Daniel Kwayisi ,&nbsp;Susanna S. Boateng ,&nbsp;Naa A. Agra ,&nbsp;Solomon Anum ,&nbsp;Raymond W. Kazapoe ,&nbsp;Abigail E. Ayikwei ,&nbsp;Chris Y. Anani ,&nbsp;Daniel K. Asiedu","doi":"10.1016/j.jafrearsci.2025.105978","DOIUrl":"10.1016/j.jafrearsci.2025.105978","url":null,"abstract":"<div><div>We present petrographical and geochemical data of paraschists and orthoamphibolite from the Suhum-Akwadum area of the Suhum Basin, Ghana, to determine their provenance, petrogenesis, and tectonic setting, and discuss the crustal evolution of the Rhyacian Birimian terrane of the West African Craton. The amphibolite exhibits trace element signatures similar to those of subalkaline basalts. Two main geochemical groups are present: (1) dominant arc-rocks with negative Nb-Ta, Ti, low Nb/Th and high La/Nb, and (2) subordinate enriched mid-ocean ridge basalts characterised by moderate to high TiO₂, positive Ta and high Nb/Th value. These compositions are interpreted as formation in a supra-subduction zone setting. The schists are geochemically classified as shales and wackes and have &lt;60 CIA, &lt;70 CIW, moderate to high Al₂O₃/TiO₂ and Na₂O/K₂O, low SiO₂/Al₂O₃, La/Sc, and Ti/Zr values. These geochemical signatures are consistent with low chemical weathering intensity, immature to moderately mature sediments and deposition in an active continental margin setting with sediments sourced from greenstone and granitoid-gneiss complexes of the Rhyacian Birimian terrane. Therefore, the current and previous geochemical data confirm the presence of an arc tectonic setting in the formation of the metasedimentary basins of the Birimian terrane. The overall geochemical data suggest that the greenstones and metasedimentary rocks formed during an orogenic event related to an arc environment where subduction zone components contributed to the generation of their parental magmas and sedimentation. This finding is consistent with the onset of “modern-style” subduction-related processes during the Archean-Paleoproterozoic transitional period.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105978"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787844","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":"Mesoproterozoic orogeny in Malawi, part 1: Irumide Domain","authors":"Thomas Fullgraf ,&nbsp;Steven D. Boger ,&nbsp;Robert J. Thomas ,&nbsp;Alexis Plunder ,&nbsp;Kondwani Dombola","doi":"10.1016/j.jafrearsci.2025.105982","DOIUrl":"10.1016/j.jafrearsci.2025.105982","url":null,"abstract":"<div><div>The Mesoproterozoic Irumide belt is a paired orogen comprising two contrasting segments. The northerly, Irumide Domain, is composed of reworked Palaeoproterozoic crust and Mesoproterozoic igneous rocks. To the south, the South Irumide Domain consists of an assembly of juvenile Mesoproterozoic arc-related crustal blocks. The suture between the two domains is a sharp tectonic contact marked by a sudden change in lithologies, magmatism and isotopic signature. This paper describes the northern segment where recent geological mapping and laboratory studies allow its precise delineation in Malawi, building upon the definitions established in adjacent Zambia and Mozambique. The Irumide Domain has been subdivided into the Mzimba, Kasungu and Mchinji subdomains. Each contains high-grade paragneisses that post-date the ∼2 Ga Ubendian orogeny. Two age-sequences are recognized; an older assemblage of paragneisses and quartzites considered to be high-grade metamorphic equivalents of the Muva Supergroup in Zambia, and including the Mafingi Group in Malawi. Detrital zircon data show that the other paragneiss sequence also contains significant contributions of ∼1100 Ma source rocks currently unknown from Zambia. These younger paragneisses, together with a suite of granitoid orthogneisses dated at ∼1080 Ma, provide evidence for a short-lived Mesoproterozoic active continental margin along the southern edge of the Congo-BaNy (combined Bangweulu Block-Nyika Subdomain) Craton. The first phase of the Irumide orogeny, resulting from arc accretion of the Irumide and South Irumide Domains to the Congo Craton, is dated at 1069 ± 9 Ma by local syntectonic anatectic melting in the suture between them. This was followed by closure of the Irumide Ocean and docking of the Proto-Kalahari craton from the south at c. 1045 Ma, which represents the main Irumide tectono-metamorphic event. Voluminous, syn-collision magmatism at c. 1040 Ma resulted from melting and assimilation of Ubendian-age continental crust from the Irumide Domain mixed with mantle-derived juvenile crust of the South Irumide Domain. Structural observations show that the Irumide Domain is sandwiched between South Irumide Domain rocks at the base of the tectonic pile and Congo Craton on top. This suggests that N-directed subduction of the Irumide Ocean beneath the Irumide Domain was followed by south-directed nappe transport during the collision phase. Our revised model of the Irumide Orogeny suggests that the main crustal architecture of southern Africa was established at the end of the Mesoproterozoic and is not just the result of the Neoproterozoic Pan-African, East African orogeny as advanced by some researchers.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105982"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837067","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":"Coastal processes and potentially toxic elements distribution in the western Moroccan Mediterranean coast (Fnideq–Azla)","authors":"Haitam Afilal ,&nbsp;Maria-Angela Bassetti ,&nbsp;Saida Bouzid ,&nbsp;Dominique Aubert ,&nbsp;Bruno Charriere ,&nbsp;Abdellah Trankil ,&nbsp;Bouchta El Moumni ,&nbsp;Ayoub El Bakkali ,&nbsp;Abdelhamid Rossi","doi":"10.1016/j.jafrearsci.2025.105965","DOIUrl":"10.1016/j.jafrearsci.2025.105965","url":null,"abstract":"<div><div>This study assesses the distribution and ecological risk of potentially toxic elements (PTEs: Cd, As, Pb, Cu, Ni, Cr, Zn, Ag) in ten surface marine sediments along the western Moroccan Mediterranean coast (Fnideq–Azla). The results demonstrate that PTE transport and accumulation are mainly driven by continental inputs, marine hydrodynamics, and coastal morphology. Oued Martil represents the main contamination source, pollutants are transported northwestward by longshore drift and subsequently trapped by the Cabo Negro and Ceuta headlands, creating distinct accumulation zones. While the geo-accumulation index (Igeo) shows varying enrichment levels, ranging from uncontaminated (Cr, Cu) to severe (Cd at Oued Martil), the Pollution load index (PLI: 1.19–2.70) indicates widespread anthropogenic impact across the region. Martil is the main pollution hotspot, followed by Fnideq, Cabo Negro, and Azla. The M'diq fishing harbor shows moderate impact, whereas the adjacent M'diq coastline and Restinga remain the least affected. Ecological risk assessment (PERI) highlights very high risk near Oued Martil and considerable risk in the northern sectors of coastal headlands. The total toxic unit (ΣTU) exceeded 3 at most sites, with Ni contributing the highest toxic load. The biological risk index (BRI: 0.17–0.42) reflects moderate risk corresponding to an 11–30 % probability of adverse effects occurring on benthic communities. Except at M'diq and Restinga, PTE levels exceeded the American National Oceanic and Atmospheric Administration (NOAA) safe thresholds. Our results surpass previous regional reports, marking this area as a critical hotspot with escalating contamination patterns.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105965"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735046","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":"Deciphering the Cenozoic detrital record of the External Rif Belt (Northern Morocco): insights for the evolution of the NW African Margin","authors":"Juan Carlos Cañaveras,&nbsp;Manuel Martín-Martín","doi":"10.1016/j.jafrearsci.2025.105970","DOIUrl":"10.1016/j.jafrearsci.2025.105970","url":null,"abstract":"<div><div>This study investigates the Cenozoic geodynamic, palaeogeographic, and palaeoclimatic evolution of the Moroccan NW African Margin through petrographic analysis of 18 stratigraphic sections across the Maghrebian Flysch Basin and the External Rif Zone. Detrital samples (comprising arenites and microconglomerates) are classified as quartzarenites, sublitharenites, and litharenites. These rocks are dominated by quartz and lithics, with scarce intrabasinal carbonate content. Provenance signatures reveal a polycyclic origin with the presence of low-to medium-grade metamorphic sources, likely derived from pre-Alpine orogens (African Craton, Pan-African belt, and/or Variscan mesetas), with contributions from plutonic intrusions. During the Oligo-Miocene, sections show increased quartz, particularly in distal foreland domains, reflecting tectonic uplift and enhanced recycling. Minor mafic input in the Intrarif/Mesorif suggests episodic oceanic crust or subduction-related volcanic contributions. Palaeoclimate proxies suggest moderate to high chemical weathering, with peak warming and aridity during the Paleocene-Eocene and Middle-Late Miocene intervals. Textural maturity ranges from well-sorted quartzarenites to submature arenites, supported by low content of feldspar and unstable grains content, suggesting a history of prolonged sediment transport, multicyclic recycling, and diagenetic overprinting. Comparative analysis with the South Iberian, North Tunisian, West Adriatic and Moldavidian- Scythian-Moessian Margins show inmature sediments in the internal areas, ultramature sediments close to the foreland and mixed succession of the two formers in intermediate positions. In particular, the South Iberian Margin shares quartz-lithic dominance but lacks metamorphic/plutonic clasts, whereas the West Adriatic Margin is characterized by persistent arc-derived volcanoclastics. These disparities highlight distinct geodynamic and palaeogeographic regimes across the Western Tethys during the Cenozoic. Our findings constrain orogenic recycling, sediment routing, and climatic feedbacks in the NW African Margin, providing insights for Mediterranean Alpine belts geodynamic reconstructions.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105970"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787842","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":"Mapping landslide susceptibility in Wolaita Zone, Ethiopia, using geospatial techniques and multi-criteria decision-making analysis","authors":"Selemon Thomas Fakana ,&nbsp;Fekadu Fanjana Falta ,&nbsp;Megegn Mada Mano ,&nbsp;Elias Bojago ,&nbsp;Mekonen Shibru Gebremariam ,&nbsp;Mathewos Markos Fakana","doi":"10.1016/j.jafrearsci.2025.105991","DOIUrl":"10.1016/j.jafrearsci.2025.105991","url":null,"abstract":"<div><div>Landslides are among the most destructive geo-environmental hazards, posing significant risks to lives, infrastructure, and livelihoods. This study aims to assess and map landslide susceptibility in the Wolaita Zone, Ethiopia, using an integrated geospatial and multi-criteria decision-making (MCDM) approach. The input datasets were obtained from various sources, including USGS Earth Explorer, NASA POWER, and World Geologic Maps, and analyzed using ArcGIS 10.8.2 software. A total of fourteen causative factors were selected based on expert knowledge, literature review, and data availability, and categorized into five domains: topographical, hydrological, geological, anthropogenic, and environmental. Each factor was standardized and weighted using the Analytical Hierarchy Process (AHP), ensuring consistency in judgment and reflecting relative influence on landslide occurrences. Results revealed that approximately 1.27 km² (0.04 %), 426.9 km² (9.78 %), 2731.43 km² (62.6 %), and 1203.53 km² (27.58 %) of the study region are highly susceptible, susceptible, moderately susceptible, and less susceptible, respectively. Areas with steep slopes, high rainfall, sparse vegetation, proximity to streams, and certain lithological formations were more susceptible to landslides. Validation using expert field observation at landslide locations and consistency ratios confirmed the reliability of the model. This susceptibility map provides crucial spatial information for planners, disaster risk managers, and policymakers to prioritize areas for intervention, early warning systems, and land-use regulation. The methodology also serves as a replicable framework for landslide risk assessment in other data-scarce and hazard-prone regions. This study presents a flexible, cost-effective, and scientifically robust framework for landslide risk mapping that can be applied regionally, particularly in data-scarce and hazard-prone areas. It advances local disaster risk reduction and mitigation, climate resilience, and sustainable land-use planning.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105991"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880644","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 geophysical and geological assessment of groundwater occurrence in the Dodoma region, central Tanzania","authors":"Uwezo Frank Mao ,&nbsp;Benatus Norbert Mvile ,&nbsp;Mahamuda Abu ,&nbsp;Emmanuel Sulungu","doi":"10.1016/j.jafrearsci.2025.105951","DOIUrl":"10.1016/j.jafrearsci.2025.105951","url":null,"abstract":"<div><div>The Dodoma region of central Tanzania is a semi-arid climatic region underlain by crystalline basement rocks. Like other semi-arid zones, it faces acute groundwater scarcity due to erratic rainfall and over-extraction driven by population growth and industrialization. This study applies an integrated geophysical and geological approach to delineate groundwater resources and assess structural controls on their occurrence. By combining airborne gravity and magnetic data with geological mapping and borehole information, key groundwater-bearing structures such as faults, fractures, shear zones, and dykes were identified. Areas with low-density and low-magnetic anomalies, particularly in the southeastern and central parts, coincide with structurally deformed zones that enhance porosity and permeability. Topographic depressions and fault intersections were also found to facilitate recharge. The results confirm that a multidisciplinary framework improves the reliability of aquifer characterization in crystalline terrains. This approach provides a practical, cost-effective solution for groundwater exploration in semi-arid regions, supporting sustainable water resource management amid rising demand.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105951"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145659070","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":"Reservoir architecture, diagenesis, and compartmentalization in syn-rift gravity-flow systems: Insights from the Gulf of Suez Rift basin","authors":"Ahmed A. Kassem","doi":"10.1016/j.jafrearsci.2025.105955","DOIUrl":"10.1016/j.jafrearsci.2025.105955","url":null,"abstract":"<div><div>The Miocene Asl Member in the North October Field, Gulf of Suez Rift, offers a well-exposed case study of syn-rift slope-apron sedimentation, where gravity-driven depositional processes, Syn-depositional faulting, and diagenetic evolution combine to create highly heterogeneous reservoirs. This integrated study synthesizes detailed core facies analysis, petrography analysis, structural interpretation, and dynamic production data to construct a predictive reservoir model linking facies architecture to reservoir performance. The methodology integrates 230 ft of conventional core description, thin-section petrography, SEM imaging, porosity–permeability measurements, and historical production data from three wells (GS172-2, GS183-1, and OCT-J5) to ensure quantitative and reproducible interpretation. Three principal facies associations: Facies A: sand-prone gravity flows, Facies B: heterolithic debris flows and Facies C: carbonate-rich deposits establish a complex stratigraphic framework, vertically partitioned by diagenetic baffles and laterally segmented by active growth faulting. Diagenetic processes, particularly feldspar dissolution and pervasive carbonate cementation, amplify contrasts in reservoir quality, controlling porosity-permeability distributions across facies. Structural and stratigraphic compartmentalization govern distinct pressure regimes and flow unit behavior, reflected in differential production responses between fault blocks. High initial oil production is sustained from clean, sand-prone compartments, while water breakthrough and rapid decline are strongly influenced by intra-reservoir heterogeneity. The Asl Member case study enhances understanding of how sedimentary, diagenetic, and structural factors interact to shape reservoir performance in syn-rift settings, providing a methodological framework applicable to other tectonically active rifted margins. The multi-disciplinary approach presented here offers an effective predictive framework for exploration and development strategies in structurally complex clastic reservoirs worldwide.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105955"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735045","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":"Integrating hydrogeochemical analysis and machine learning to assess surface–groundwater interactions in an arid basin (Middle Egypt)","authors":"Ahmed A. Abdelhady ,&nbsp;Mamdouh S. Morsi ,&nbsp;Nouria E.A. Aboshaala ,&nbsp;Mahmoud M. Khalil ,&nbsp;Hadi M. Elshourbagi ,&nbsp;Esam Ismail ,&nbsp;Esam El Sayed ,&nbsp;Ashraf M.T. Elewa ,&nbsp;Emad Youssef ,&nbsp;Basma A.A. Balboul","doi":"10.1016/j.jafrearsci.2025.105988","DOIUrl":"10.1016/j.jafrearsci.2025.105988","url":null,"abstract":"<div><div>Understanding surface–groundwater interactions is essential for sustainable water resource management in arid regions, where water scarcity and water quality degradation pose critical challenges. This study explored the hydrochemical characteristics, dominant controlling processes, and linkages between surface water and groundwater in the arid Middle Egypt basin. Hydrochemical facies and major physicochemical parameters were compared for both water types, supported by multivariate statistics (principal component analysis and PERMANOVA) and machine-learning approaches (Random Forest and a hybrid K-nearest neighbor model). Results revealed distinct hydrochemical signatures, with surface waters characterized mainly by bicarbonate facies and groundwater exhibiting more mineralized sodium chloride and calcium chloride facies. Hydrochemical patterns suggest that surface water chemistry is influenced by evaporative concentration, whereas groundwater composition reflects mineral dissolution and cation exchange; however, these process interpretations are considered first-order and indicative rather than diagnostic. Random Forest analysis identified total cations, total anions, and electrical conductivity as the most important variables discriminating between surface water and groundwater. The hybrid KNN model indicated that surface water chemistry alone provided the strongest basis for predicting groundwater composition, with relatively high performance for Na, Cl, and Mg (R² = 0.71–0.84) but weak performance for hardness and sulfate. Chemical similarity showed no systematic distance-decay relationship, and spatial proximity was not a primary control on surface–groundwater chemical relationships. These findings highlight contrasting hydrogeochemical controls on surface water and groundwater in the Nile Valley and demonstrate the value of integrating hydrochemical analysis with machine-learning tools for improving understanding of surface–groundwater interactions in arid environments.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105988"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880643","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}