Pub Date : 2026-03-01Epub Date: 2025-12-13DOI: 10.1016/j.jafrearsci.2025.105979
Solomon Nehemiah Yusuf , Ezekiel Yusuf Yenne , Mubarak Umar Faruk
Lineament detection and depth estimation methods based on advanced aeromagnetic data were applied to the Nigerian sector of the Chad (Bornu) Basin to delineate structural framework, basement configuration and evaluate their hydrocarbon significance. Power spectral analysis was used to separate deep and shallow magnetic sources, while Euler deconvolution and finite local wavenumber techniques estimated basement depths and mapped major fault systems. Derivative-based filters such as the second vertical derivatives (SVD), analytic signal and Goussev filter enhanced the definition of intrusive and tectonic features. The interpreted structures mainly trend NE–SW, ENE–WSW, and NNE–SSW, aligning with Pan-African reactivation and Cretaceous rifting that formed the basin. The depth of the basement ranges from 1 to 5 km, while sedimentary thicknesses lie between 2.3 and 5.2 km, suggesting substantial sedimentary sequences conducive to hydrocarbons generation and accumulation. Structural lows align with depocentres related to thermal maturation zones, whereas multiple mapped faults coincide with current deep well sites (Ngamma East-1, Ngor North-1, Kanadi-1, Krumta-1, and Murshe-01). The results confirm that basement geometry and fault-controlled deformation significantly influence hydrocarbon migration pathways within the Bornu Basin.
{"title":"Basement architecture and structural styles of part of the Nigerian sector of the Chad Basin (Bornu Basin)","authors":"Solomon Nehemiah Yusuf , Ezekiel Yusuf Yenne , Mubarak Umar Faruk","doi":"10.1016/j.jafrearsci.2025.105979","DOIUrl":"10.1016/j.jafrearsci.2025.105979","url":null,"abstract":"<div><div>Lineament detection and depth estimation methods based on advanced aeromagnetic data were applied to the Nigerian sector of the Chad (Bornu) Basin to delineate structural framework, basement configuration and evaluate their hydrocarbon significance. Power spectral analysis was used to separate deep and shallow magnetic sources, while Euler deconvolution and finite local wavenumber techniques estimated basement depths and mapped major fault systems. Derivative-based filters such as the second vertical derivatives (SVD), analytic signal and Goussev filter enhanced the definition of intrusive and tectonic features. The interpreted structures mainly trend NE–SW, ENE–WSW, and NNE–SSW, aligning with Pan-African reactivation and Cretaceous rifting that formed the basin. The depth of the basement ranges from 1 to 5 km, while sedimentary thicknesses lie between 2.3 and 5.2 km, suggesting substantial sedimentary sequences conducive to hydrocarbons generation and accumulation. Structural lows align with depocentres related to thermal maturation zones, whereas multiple mapped faults coincide with current deep well sites (Ngamma East-1, Ngor North-1, Kanadi-1, Krumta-1, and Murshe-01). The results confirm that basement geometry and fault-controlled deformation significantly influence hydrocarbon migration pathways within the Bornu Basin.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105979"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787916","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}
Pub Date : 2026-03-01Epub Date: 2025-12-05DOI: 10.1016/j.jafrearsci.2025.105964
Benjamin F. Walter , Ndukauba Egesi , Mohsin Raza , Micheal Agbebia , Fadila Adamu , R. Johannes Giebel , Michael A.W. Marks , Emmanuel Chidi Ugbaja , Gregor Markl
Unconformity-related hydrothermal vein-type deposits are key sources of high-purity fluorite, baryte, and base metals, with occurrences in Nigeria, particularly along the Benue Trough. However, the genesis of the Nigerian deposits is not well understood. This study examines fluid inclusion systematics from mineralized veins at Enyigba, Ameta, Ikwo, Otim Land, and Uburu-Abakaliki, using microthermometry, crush-leach analysis, and Raman spectroscopy. Fluid inclusion microthermometry reveals homogenization temperatures between 99 and 190 °C and salinities of 18.3–22 wt%NaCl + CaCl2, typical of unconformity-related hydrothermal vein systems. Geochemical data indicate the mineralizing fluids resulted from mixing of bittern brines (low Cl/Br), halite-dissolution brines (high Cl/Br), and oilfield brines, as shown by Cl/Br ratios and Rb/Cs values. Microraman spectroscopy suggests the presence of hydrocarbons, supporting the involvement of reduced oilfield brines. These findings point to a complex fluid mixing process, likely driven by crustal-scale faulting during the rifting of the Benue Trough in the context of Pangaea break-up. This research suggests a common ore-forming process for the Nigerian deposits.
{"title":"Unconformity-related fluorite-baryte-base metal mineralization in the Benue Trough, Nigeria: A multifluid origin triggered by the separation of Pangaea","authors":"Benjamin F. Walter , Ndukauba Egesi , Mohsin Raza , Micheal Agbebia , Fadila Adamu , R. Johannes Giebel , Michael A.W. Marks , Emmanuel Chidi Ugbaja , Gregor Markl","doi":"10.1016/j.jafrearsci.2025.105964","DOIUrl":"10.1016/j.jafrearsci.2025.105964","url":null,"abstract":"<div><div>Unconformity-related hydrothermal vein-type deposits are key sources of high-purity fluorite, baryte, and base metals, with occurrences in Nigeria, particularly along the Benue Trough. However, the genesis of the Nigerian deposits is not well understood. This study examines fluid inclusion systematics from mineralized veins at Enyigba, Ameta, Ikwo, Otim Land, and Uburu-Abakaliki, using microthermometry, crush-leach analysis, and Raman spectroscopy. Fluid inclusion microthermometry reveals homogenization temperatures between 99 and 190 °C and salinities of 18.3–22 wt%NaCl + CaCl<sub>2</sub>, typical of unconformity-related hydrothermal vein systems. Geochemical data indicate the mineralizing fluids resulted from mixing of bittern brines (low Cl/Br), halite-dissolution brines (high Cl/Br), and oilfield brines, as shown by Cl/Br ratios and Rb/Cs values. Microraman spectroscopy suggests the presence of hydrocarbons, supporting the involvement of reduced oilfield brines. These findings point to a complex fluid mixing process, likely driven by crustal-scale faulting during the rifting of the Benue Trough in the context of Pangaea break-up. This research suggests a common ore-forming process for the Nigerian deposits.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105964"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787919","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}
Pub Date : 2026-03-01Epub Date: 2025-12-14DOI: 10.1016/j.jafrearsci.2025.105980
Mohammed Bouchkara , Nouhaila Erraji Chahid , Imane Joudar , Otmane Khalfaoui , Hamza El Behja , Aïssa Benazzouz , Bendahhou Zourarah , Khalid El Khalidi
Coastal lagoons are dynamic coastal ecosystems that support biodiversity, regulate water quality, and provide essential ecological services. Understanding their sediment dynamics is crucial for sustainable management, particularly under growing human pressures and climate change impacts. This study investigates the hydrodynamic and sedimentary processes of the Oualidia Lagoon (Morocco) by integrating numerical hydrodynamic modelling (MIKE 21) with field observations. Tidal currents, wave action, and water levels were simulated, while Root Mean Square Velocity (RMSV) and water residence time (REST) were used to evaluate circulation efficiency and water retention. The results reveal pronounced spatial variability in hydrodynamic energy. Peak current speeds exceed 1 m s−1 near the tidal inlets during spring tides, while wave analysis shows the dominance of NNW and WNW swells, which drive longshore drift and promote sediment deposition toward the sandpit and inlets. Based on RMSV and REST, three hydrodynamic zones were identified: a high-energy zone with coarse sands and limited deposition, a moderate-energy zone where erosion and deposition are balanced, and a low-energy zone favoring the accumulation of fine sediments.
This zonal classification demonstrates how hydrodynamic forcing controls sediment transport and distribution, thereby shaping the lagoon's geomorphological evolution. Importantly, this study provides a post-evaluation of management interventions such as sediment-trap dredging and dike breaching illustrating how these measures modified water circulation, reduced sediment confinement, and altered the hydrodynamic drivers of sediment transport.
沿海泻湖是动态的沿海生态系统，支持生物多样性，调节水质，并提供必要的生态服务。了解其沉积物动态对于可持续管理至关重要，特别是在人类压力和气候变化影响日益增加的情况下。本文采用数值水动力模拟（MIKE 21）和野外观测相结合的方法，研究了摩洛哥Oualidia泻湖的水动力和沉积过程。模拟潮流、波浪作用和水位，采用均方根流速（RMSV）和水停留时间（REST）评价循环效率和保水能力。结果表明，水动力能的空间变异性明显。大潮时，潮口附近水流峰值速度超过1 m s−1，波浪分析表明，NNW和WNW的浪涌主导了滨岸漂移，促使泥沙向沙坑和潮口沉积。基于RMSV和REST，确定了3个水动力带：粗砂沉积有限的高能带、侵蚀与沉积平衡的中能带和有利于细砂堆积的低能带。这种地带性分类说明了水动力强迫如何控制沉积物的运输和分布，从而塑造了泻湖的地貌演变。重要的是，本研究提供了管理干预措施的后评价，如疏浚沉积物陷阱和决堤，说明这些措施如何改变水循环，减少沉积物限制，并改变沉积物运输的水动力驱动因素。
{"title":"Effect of hydrodynamic regimes on sediment transport and grain size distribution in the Oualidia Lagoon (Morocco): A numerical modeling approach","authors":"Mohammed Bouchkara , Nouhaila Erraji Chahid , Imane Joudar , Otmane Khalfaoui , Hamza El Behja , Aïssa Benazzouz , Bendahhou Zourarah , Khalid El Khalidi","doi":"10.1016/j.jafrearsci.2025.105980","DOIUrl":"10.1016/j.jafrearsci.2025.105980","url":null,"abstract":"<div><div>Coastal lagoons are dynamic coastal ecosystems that support biodiversity, regulate water quality, and provide essential ecological services. Understanding their sediment dynamics is crucial for sustainable management, particularly under growing human pressures and climate change impacts. This study investigates the hydrodynamic and sedimentary processes of the Oualidia Lagoon (Morocco) by integrating numerical hydrodynamic modelling (MIKE 21) with field observations. Tidal currents, wave action, and water levels were simulated, while Root Mean Square Velocity (RMSV) and water residence time (REST) were used to evaluate circulation efficiency and water retention. The results reveal pronounced spatial variability in hydrodynamic energy. Peak current speeds exceed 1 m s<sup>−1</sup> near the tidal inlets during spring tides, while wave analysis shows the dominance of NNW and WNW swells, which drive longshore drift and promote sediment deposition toward the sandpit and inlets. Based on RMSV and REST, three hydrodynamic zones were identified: a high-energy zone with coarse sands and limited deposition, a moderate-energy zone where erosion and deposition are balanced, and a low-energy zone favoring the accumulation of fine sediments.</div><div>This zonal classification demonstrates how hydrodynamic forcing controls sediment transport and distribution, thereby shaping the lagoon's geomorphological evolution. Importantly, this study provides a post-evaluation of management interventions such as sediment-trap dredging and dike breaching illustrating how these measures modified water circulation, reduced sediment confinement, and altered the hydrodynamic drivers of sediment transport.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105980"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787843","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}
Pub Date : 2026-03-01Epub Date: 2025-12-19DOI: 10.1016/j.jafrearsci.2025.105985
Muhammet Çınar , Mitat Öztürk , Ahmet Özbek , Alican Kop , Bahadır Çelik
Soil liquefaction is a significant geotechnical hazard in earthquake-prone regions, threatening infrastructure, human safety, and economic stability. This study investigates the spatial and depth-dependent characteristics of liquefaction potential of the Türkoğlu district in Kahramanmaraş Province, a region severely impacted by the February 6, 2023, Kahramanmaraş earthquake sequence (Mw 7.8 and Mw 7.6). A total of 28 boreholes were drilled to obtain geological and geotechnical data, including soil stratigraphy, groundwater level, and Standard Penetration Test (SPT) results, with disturbed and undisturbed samples collected for laboratory analysis. Liquefaction assessments were conducted using the Simplified Procedure for an Mw 7.8 scenario and a peak ground acceleration (PGA) of 0.665 g, calculating the Liquefaction Potential Index (LPI) and Liquefaction Severity Index (LSI) for each site. LSI values ranged from 0 to 83.75, indicating risk levels from non-liquefiable to high hazard. The results were integrated into a Geographic Information System (GIS) to produce spatial liquefaction hazard maps at depths of 4 m, 8 m, and 12 m through geostatistical interpolation. The findings indicate that 76 % of the boreholes exhibit high to very high liquefaction potential according to LPI, and 60 % show moderate to high hazard according to LSI. These findings provide essential input for earthquake risk mitigation and sustainable urban planning in the Türkoğlu district.
{"title":"GIS-based evaluation of liquefaction susceptibility in the Türkoğlu district, Kahramanmaraş: A comparative analysis using LPI and LSI","authors":"Muhammet Çınar , Mitat Öztürk , Ahmet Özbek , Alican Kop , Bahadır Çelik","doi":"10.1016/j.jafrearsci.2025.105985","DOIUrl":"10.1016/j.jafrearsci.2025.105985","url":null,"abstract":"<div><div>Soil liquefaction is a significant geotechnical hazard in earthquake-prone regions, threatening infrastructure, human safety, and economic stability. This study investigates the spatial and depth-dependent characteristics of liquefaction potential of the Türkoğlu district in Kahramanmaraş Province, a region severely impacted by the February 6, 2023, Kahramanmaraş earthquake sequence (Mw 7.8 and Mw 7.6). A total of 28 boreholes were drilled to obtain geological and geotechnical data, including soil stratigraphy, groundwater level, and Standard Penetration Test (SPT) results, with disturbed and undisturbed samples collected for laboratory analysis. Liquefaction assessments were conducted using the Simplified Procedure for an Mw 7.8 scenario and a peak ground acceleration (PGA) of 0.665 g, calculating the Liquefaction Potential Index (LPI) and Liquefaction Severity Index (LSI) for each site. LSI values ranged from 0 to 83.75, indicating risk levels from non-liquefiable to high hazard. The results were integrated into a Geographic Information System (GIS) to produce spatial liquefaction hazard maps at depths of 4 m, 8 m, and 12 m through geostatistical interpolation. The findings indicate that 76 % of the boreholes exhibit high to very high liquefaction potential according to LPI, and 60 % show moderate to high hazard according to LSI. These findings provide essential input for earthquake risk mitigation and sustainable urban planning in the Türkoğlu district.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105985"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837032","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}
Pub Date : 2026-03-01Epub Date: 2025-12-13DOI: 10.1016/j.jafrearsci.2025.105969
Hesham M. El-Asmar, Mahmoud Sh. Felfla, Zaki A. Abdel-Fattah, Ehab M. Assal
The El Daba'a Plateau, located along Egypt's northwestern Mediterranean coast, provides an excellent natural laboratory for investigating the interplay between neotectonics and Quaternary coastal evolution. This study integrates geomorphological, stratigraphic, and ground magnetic data to elucidate the plateau's morphotectonic development. The exposed succession comprises the Middle Miocene Marmarica Formation, including the Oasis and Siwa Escarpment Members, unconformably overlain by the Quaternary Alexandria Formation, which consists of Pleistocene–Holocene Third, Second and First aeolianite ridges. Magnetic investigations identified four Late Pleistocene normal faults, striking WNW–ESE and NNW–SSE at Jumaymah–Saniyat Turabiyah and Wadi Abu Samra, associated with vertical displacements of up to 15 m, and two ENE–WSW across the plateau's central part. These faults controlled the formation of coastal escarpments and low-lying embayments, moulding the plateau's present-day morphology. The integration of morphostratigraphic and geophysical datasets highlights novel findings regarding the neotectonic imprint along Egypt's northern passive margin and provides new insights into Late Quaternary crustal deformation and coastal evolution in the southeastern Mediterranean, with implications for regional geohazard assessment and landscape evolution models.
El Daba’a高原位于埃及西北地中海沿岸，为研究新构造与第四纪海岸演化之间的相互作用提供了一个极好的自然实验室。该研究综合了地貌、地层学和地磁资料，阐明了青藏高原的形态构造发育。暴露的序列包括中中新世马尔马里卡组，包括绿洲和Siwa陡坡段，被第四纪亚历山大组不整合覆盖，后者由更新世-全新世第三、第二和第一风成岩脊组成。磁调查发现了4条晚更新世正断层，在Jumaymah-Saniyat Turabiyah和Wadi Abu Samra处走向WNW-ESE和NNW-SSE，垂直位移高达15 m，还有2条ENE-WSW横跨高原中部。这些断层控制了海岸峭壁和低洼港湾的形成，塑造了高原今天的形态。地貌地层学和地球物理数据集的整合突出了埃及北部被动边缘新构造印记的新发现，为地中海东南部晚第四纪地壳变形和海岸演化提供了新的见解，对区域地质灾害评估和景观演化模型具有重要意义。
{"title":"The role of Late Quaternary tectonics in moulding El Daba'a Plateau NW coast of Egypt: Stratigraphic and geophysical insights","authors":"Hesham M. El-Asmar, Mahmoud Sh. Felfla, Zaki A. Abdel-Fattah, Ehab M. Assal","doi":"10.1016/j.jafrearsci.2025.105969","DOIUrl":"10.1016/j.jafrearsci.2025.105969","url":null,"abstract":"<div><div>The El Daba'a Plateau, located along Egypt's northwestern Mediterranean coast, provides an excellent natural laboratory for investigating the interplay between neotectonics and Quaternary coastal evolution. This study integrates geomorphological, stratigraphic, and ground magnetic data to elucidate the plateau's morphotectonic development. The exposed succession comprises the Middle Miocene Marmarica Formation, including the Oasis and Siwa Escarpment Members, unconformably overlain by the Quaternary Alexandria Formation, which consists of Pleistocene–Holocene Third, Second and First aeolianite ridges. Magnetic investigations identified four Late Pleistocene normal faults, striking WNW–ESE and NNW–SSE at Jumaymah–Saniyat Turabiyah and Wadi Abu Samra, associated with vertical displacements of up to 15 m, and two ENE–WSW across the plateau's central part. These faults controlled the formation of coastal escarpments and low-lying embayments, moulding the plateau's present-day morphology. The integration of morphostratigraphic and geophysical datasets highlights novel findings regarding the neotectonic imprint along Egypt's northern passive margin and provides new insights into Late Quaternary crustal deformation and coastal evolution in the southeastern Mediterranean, with implications for regional geohazard assessment and landscape evolution models.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105969"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837033","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}
Pub Date : 2026-03-01Epub Date: 2025-12-09DOI: 10.1016/j.jafrearsci.2025.105972
Iliass Naouadir , Marzieh Khalili , Salih Muhammad Awadh , Samira Adil , El Hassane Chellai , Mohammed Ettaki , Abdennabi Alitane , Abdallah Elaaraj , Zaher Mundher Yaseen
Karst aquifers in semi-arid regions are vital yet exceptionally vulnerable lifelines. This study investigates how tectonic, geomorphological, and climatic factors control the dynamics of karst springs in the El Menzel Causse (Middle Atlas, Morocco). Using an integrated approach that combines field investigations, remote sensing, and quantitative hydro-climatic analysis, we identify the mechanisms driving the system's severe decline. Results indicated that the structural architecture of the major fault systems in the North Middle Atlas Fault (NMAF) and the Median Middle Atlas Fault (MMAF), governs the spatial distribution of more than 50 springs, which occur preferentially within highly permeable fault damage zones. However, the aquifer is under severe climatic stress, evidenced by a statistically significant decline in precipitation and an increased frequency of droughts. The system's response appeared dramatic: only five springs remained active in 2024, with discharge reductions exceeding 80 % compared to historical records. Anthropogenic pressures including groundwater overextraction and wastewater contamination critically amplify this crisis. In conclusion, this research presents El Menzel as a “sentinel system” whose collapse serves as a warning for other karst regions worldwide, highlighting the urgent need for science-informed, adaptive water management strategies to prevent irreversible resource depletion.
{"title":"Climatic and tectono-geomorphological controls on karst spring dynamics: Case study of the El Menzel Causse, Middle Atlas (Morocco)","authors":"Iliass Naouadir , Marzieh Khalili , Salih Muhammad Awadh , Samira Adil , El Hassane Chellai , Mohammed Ettaki , Abdennabi Alitane , Abdallah Elaaraj , Zaher Mundher Yaseen","doi":"10.1016/j.jafrearsci.2025.105972","DOIUrl":"10.1016/j.jafrearsci.2025.105972","url":null,"abstract":"<div><div>Karst aquifers in semi-arid regions are vital yet exceptionally vulnerable lifelines. This study investigates how tectonic, geomorphological, and climatic factors control the dynamics of karst springs in the El Menzel Causse (Middle Atlas, Morocco). Using an integrated approach that combines field investigations, remote sensing, and quantitative hydro-climatic analysis, we identify the mechanisms driving the system's severe decline. Results indicated that the structural architecture of the major fault systems in the North Middle Atlas Fault (NMAF) and the Median Middle Atlas Fault (MMAF), governs the spatial distribution of more than 50 springs, which occur preferentially within highly permeable fault damage zones. However, the aquifer is under severe climatic stress, evidenced by a statistically significant decline in precipitation and an increased frequency of droughts. The system's response appeared dramatic: only five springs remained active in 2024, with discharge reductions exceeding 80 % compared to historical records. Anthropogenic pressures including groundwater overextraction and wastewater contamination critically amplify this crisis. In conclusion, this research presents El Menzel as a “sentinel system” whose collapse serves as a warning for other karst regions worldwide, highlighting the urgent need for science-informed, adaptive water management strategies to prevent irreversible resource depletion.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105972"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787786","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}
Pub Date : 2026-03-01Epub Date: 2025-11-21DOI: 10.1016/j.jafrearsci.2025.105942
Zohra Abdelkrim , Saeid Eslamian
Urban heat stress in semi-arid Algerian cities, such as Biskra, remains insufficiently studied. Investigating its spatial and temporal dynamics through integrated RS and GIS approaches is crucial for advancing sustainable urban planning and climate adaptation strategies.
This study aims to analyze the spatial and temporal variations in land surface temperature (LST) between 2011 and 2022 in Biskra, Algeria, using Remote Sensing (RS) and Geographic Information Systems (GIS) techniques. It further seeks to identify the zones most affected by elevated LST and to examine their relationship with vegetation, built-up, and water indices (NDVI, NDBI, NDWI).
The results reveal significant seasonal and decadal variations in land surface temperature (LST). During the summer months, LST exceeded 45 °C in several urban zones, reflecting strong heat accumulation and limited vegetation cover. In contrast, cooler months recorded temperatures below 20 °C, associated with higher vegetation and water presence, indicating improved ecological quality. Overall, the findings highlight how urban expansion and seasonal variability have intensified heat stress and degraded environmental conditions in Biskra semi-arid context.
The analysis reveals marked seasonal and decadal variations in urban heat across Biskra, with higher LST, intensified Surface Urban Heat Island (SUHI), and lower Urban Thermal Field Variance Index (UTFVI) values indicating pronounced heat stress and reduced ecological quality during summer, contrasted by cooler and more balanced conditions in other seasons. These results emphasize the impact of urban expansion and seasonal variability on thermal stress and the vulnerability of Biskra urban environment, highlighting the need for vegetation-oriented and sustainable urban planning. Future research should employ higher-resolution data and predictive modeling to better understand urban thermal dynamics under climate change.
{"title":"An evaluation of spatial and temporal variations of land surface temperature in Biskra, Algeria using remote sensing and GIS","authors":"Zohra Abdelkrim , Saeid Eslamian","doi":"10.1016/j.jafrearsci.2025.105942","DOIUrl":"10.1016/j.jafrearsci.2025.105942","url":null,"abstract":"<div><div>Urban heat stress in semi-arid Algerian cities, such as Biskra, remains insufficiently studied. Investigating its spatial and temporal dynamics through integrated RS and GIS approaches is crucial for advancing sustainable urban planning and climate adaptation strategies.</div><div>This study aims to analyze the spatial and temporal variations in land surface temperature (LST) between 2011 and 2022 in Biskra, Algeria, using Remote Sensing (RS) and Geographic Information Systems (GIS) techniques. It further seeks to identify the zones most affected by elevated LST and to examine their relationship with vegetation, built-up, and water indices (NDVI, NDBI, NDWI).</div><div>The results reveal significant seasonal and decadal variations in land surface temperature (LST). During the summer months, LST exceeded 45 °C in several urban zones, reflecting strong heat accumulation and limited vegetation cover. In contrast, cooler months recorded temperatures below 20 °C, associated with higher vegetation and water presence, indicating improved ecological quality. Overall, the findings highlight how urban expansion and seasonal variability have intensified heat stress and degraded environmental conditions in Biskra semi-arid context.</div><div>The analysis reveals marked seasonal and decadal variations in urban heat across Biskra, with higher LST, intensified Surface Urban Heat Island (SUHI), and lower Urban Thermal Field Variance Index (UTFVI) values indicating pronounced heat stress and reduced ecological quality during summer, contrasted by cooler and more balanced conditions in other seasons. These results emphasize the impact of urban expansion and seasonal variability on thermal stress and the vulnerability of Biskra urban environment, highlighting the need for vegetation-oriented and sustainable urban planning. Future research should employ higher-resolution data and predictive modeling to better understand urban thermal dynamics under climate change.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105942"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735098","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}
Pub Date : 2026-03-01Epub Date: 2025-12-23DOI: 10.1016/j.jafrearsci.2025.105947
Abdessamia El Alaoui , Nawal Bouya , Bennacer Moussaid , Said Ou Moua , Lahssen Baidder , Ahmed Fadili , Imane Haidara , Mohammed Slimani
{"title":"Corrigendum to “The role of structural legacy in the compartmentalization of the Témara aquifer, Morocco: Insight from electrical resistivity tomography and field geological data” [J. Afr. Earth Sci. 234 (2026) 105935]","authors":"Abdessamia El Alaoui , Nawal Bouya , Bennacer Moussaid , Said Ou Moua , Lahssen Baidder , Ahmed Fadili , Imane Haidara , Mohammed Slimani","doi":"10.1016/j.jafrearsci.2025.105947","DOIUrl":"10.1016/j.jafrearsci.2025.105947","url":null,"abstract":"","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105947"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145921769","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}
The Achemmach region, located east of the El Hammam district in northeastern Central Morocco, is characterized by significant tin mineralization. This mineralization is hosted in E-W trending Late Visean tourmaline-bearing brecciated veins developed within sandstones and mudstones, contrasting with barren NE-SW trending tourmaline structures. Electron microprobe analyses reveal that tourmalines from the barren zones belong to metamorphic-type schorl-dravite solid solutions (up to 50 mol% dravite), whereas those from mineralized zones are granitic schorlites with significant fluorine contents (up to 0.15 apfu F). A paragenetic assemblage composed of cassiterite, stannite, chalcopyrite, arsenopyrite, pyrite, and sphalerite was identified from surface and core samples. Stannite, abundant in the mineralized veins, forms through reactions between cassiterite and Cu-rich fluids contemporaneous with chalcopyrite precipitation. Quartz, tourmaline, calcite, and fluorite constitute the principal gangue minerals. Stannite contains minor Au (up to 350 ppm) and Ag (up to 0.27 wt%), whereas cassiterite hosts up to 790 ppm Au and 600 ppm Ag. Fluid inclusion studies in quartz from tourmalinized veins indicate a progressive evolution from vapor-to supercritical aqueous fluids trapped at conditions between 500 °C/700 bar and 150 °C/100 bar. Fluids from barren veins show higher salinities than those from mineralized zones, reflecting a more metamorphic origin. The hydrothermal evolution of the Achemmach tin-bearing breccias involves two key stages: (1) trapping of vapor-rich fluids at ∼600 °C/1 kbar with salinity of ∼13.5 wt% NaCl equiv., and (2) prolonged boiling down to ∼100 °C, evidenced by increased fluid salinities.
{"title":"Tin rich and barren tourmalines of Achemmach (El Hammam district, central Morocco): Mineralogy and physico-chemical characteristics of fluid phases","authors":"Azizi Moussaid , Hafid Mezougane , Ilyasse Loudaoued , Mohmed Aissa , Abdelali Kharis , Panagiotis Voudouris , Mohamed Aissa , Mustapha Souhassou , Muhammad Souiri , Abderrahim Ardouz , Hafid Ouahmad","doi":"10.1016/j.jafrearsci.2025.105973","DOIUrl":"10.1016/j.jafrearsci.2025.105973","url":null,"abstract":"<div><div>The Achemmach region, located east of the El Hammam district in northeastern Central Morocco, is characterized by significant tin mineralization. This mineralization is hosted in E-W trending Late Visean tourmaline-bearing brecciated veins developed within sandstones and mudstones, contrasting with barren NE-SW trending tourmaline structures. Electron microprobe analyses reveal that tourmalines from the barren zones belong to metamorphic-type schorl-dravite solid solutions (up to 50 mol% dravite), whereas those from mineralized zones are granitic schorlites with significant fluorine contents (up to 0.15 apfu F). A paragenetic assemblage composed of cassiterite, stannite, chalcopyrite, arsenopyrite, pyrite, and sphalerite was identified from surface and core samples. Stannite, abundant in the mineralized veins, forms through reactions between cassiterite and Cu-rich fluids contemporaneous with chalcopyrite precipitation. Quartz, tourmaline, calcite, and fluorite constitute the principal gangue minerals. Stannite contains minor Au (up to 350 ppm) and Ag (up to 0.27 wt%), whereas cassiterite hosts up to 790 ppm Au and 600 ppm Ag. Fluid inclusion studies in quartz from tourmalinized veins indicate a progressive evolution from vapor-to supercritical aqueous fluids trapped at conditions between 500 °C/700 bar and 150 °C/100 bar. Fluids from barren veins show higher salinities than those from mineralized zones, reflecting a more metamorphic origin. The hydrothermal evolution of the Achemmach tin-bearing breccias involves two key stages: (1) trapping of vapor-rich fluids at ∼600 °C/1 kbar with salinity of ∼13.5 wt% NaCl equiv., and (2) prolonged boiling down to ∼100 °C, evidenced by increased fluid salinities.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"235 ","pages":"Article 105973"},"PeriodicalIF":2.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787917","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}
Effective groundwater management in semi-arid regions requires detailed aquifer characterization, particularly in ecosystems facing ecohydrological stress. This study characterizes aquifer systems in the southern Kruger National Park (KNP) to support the conceptualization and protection of groundwater-dependent ecosystems (GDEs). Pre-existing single-well and multiple well constant rate pumping test data from five boreholes were analyzed to estimate key aquifer parameters. Borehole logs and geological cross-sections were used to identify preferential groundwater flow paths and delineate potential recharge and discharge zones. Groundwater recharge and evapotranspiration were estimated using the Cumulative Rainfall Departure (CRD) method, the Rainfall Infiltration Breakthrough (RIB) method, and remotely sensed FAO datasets. Results show that the region's aquifers consist of shallow weathered and deeper fractured granitic/gneiss units of the Archaean Nelspruit formation, with thicknesses ranging from 299 to 383 m. Transmissivity values ranged from 0.5 to 11.2 m2/day and Storativity from 1.28 × 10−6 to 4.38 × 10−4, indicating generally low aquifer permeability except in localized fractured zones. Dyke intrusions were found to influence groundwater occurrence and the distribution of GDEs. The study underscores the importance of integrated hydrogeological analysis for accurately conceptualizing GDEs beyond surface indicators that overlook subsurface connectivity. It provides a foundational understanding of aquifer–ecosystem interactions and highlights the need to incorporate these relationships, along with spatial and temporal groundwater variability, into numerical models. This approach supports more effective simulation, protection, and policy development for GDE management.
{"title":"Aquifer characterization for improved hydrogeological conceptualization of groundwater dependent ecosystems in the Kruger National Park, South Africa","authors":"Qawekazi Msesane , Timothy Dube , Siyamthanda Gxokwe , Eddie Riddell , Tatenda Dalu","doi":"10.1016/j.jafrearsci.2025.105884","DOIUrl":"10.1016/j.jafrearsci.2025.105884","url":null,"abstract":"<div><div>Effective groundwater management in semi-arid regions requires detailed aquifer characterization, particularly in ecosystems facing ecohydrological stress. This study characterizes aquifer systems in the southern Kruger National Park (KNP) to support the conceptualization and protection of groundwater-dependent ecosystems (GDEs). Pre-existing single-well and multiple well constant rate pumping test data from five boreholes were analyzed to estimate key aquifer parameters. Borehole logs and geological cross-sections were used to identify preferential groundwater flow paths and delineate potential recharge and discharge zones. Groundwater recharge and evapotranspiration were estimated using the Cumulative Rainfall Departure (CRD) method, the Rainfall Infiltration Breakthrough (RIB) method, and remotely sensed FAO datasets. Results show that the region's aquifers consist of shallow weathered and deeper fractured granitic/gneiss units of the Archaean Nelspruit formation, with thicknesses ranging from 299 to 383 m. Transmissivity values ranged from 0.5 to 11.2 m<sup>2</sup>/day and Storativity from 1.28 × 10<sup>−6</sup> to 4.38 × 10<sup>−4</sup>, indicating generally low aquifer permeability except in localized fractured zones. Dyke intrusions were found to influence groundwater occurrence and the distribution of GDEs. The study underscores the importance of integrated hydrogeological analysis for accurately conceptualizing GDEs beyond surface indicators that overlook subsurface connectivity. It provides a foundational understanding of aquifer–ecosystem interactions and highlights the need to incorporate these relationships, along with spatial and temporal groundwater variability, into numerical models. This approach supports more effective simulation, protection, and policy development for GDE management.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"233 ","pages":"Article 105884"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145324914","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号