Journal of African Earth Sciences最新文献

{"title":"Petrogenesis and geochronology of the East Laouni mafic intrusion (Central Hoggar, Tuareg shield, Algeria): Constraints from mineralogical, geochemical, and zircon U–Pb–Hf isotopic data","authors":"Ahmed El Amine Alouache ,&nbsp;Nacéra Remaci-Bénaouda ,&nbsp;Jean Yves Cottin","doi":"10.1016/j.jafrearsci.2026.105995","DOIUrl":"10.1016/j.jafrearsci.2026.105995","url":null,"abstract":"<div><div>The East Laouni mafic intrusion (ELMI) is an elliptical magmatic body outcropping in the Laouni terrane of the LATEA metacraton, Central Hoggar. It is composed of troctolite, olivine gabbro, anorthosite, and gabbronorite. This study presents integrated geochronological, petrographic, mineralogical, and geochemical data to unravel the igneous processes that took place in the ELMI chamber. Uranium-lead isotopic analysis of zircons revealed an age of 633.3 ± 2.1 Ma, indicating that the ELMI crystallized at the beginning of the post-collisional stage of the Pan-African orogeny. The zircons also show a sub-chondritic ε_Hf(t) value (−5.44) with a crustal model age (Hf<span><math><mrow><msubsup><mi>T</mi><mtext>DM</mtext><mi>C</mi></msubsup></mrow></math></span>) of around 1.92 Ga, indicating significant contamination of the mantle parent magma by crustal material of Eburnian age (≈2 Ga). The troctolites are essentially adcumulates composed of plagioclase (An₆₄–An₇₄) showing shape-preferred orientation (SPO) and signs of adcumulate growth and olivine (Fo₇₆–Fo₇₉) that is sometimes corroded, accompanied by intercumulus clino- and orthopyroxene. In olivine gabbros, displaying meso-to orthocumulate textures, the SPO of plagioclases (An₅₆–An₇₀) is relatively weak. Olivine (Fo₇₀–Fo₇₅) is highly corroded, and its proportion decreases in favour of clinopyroxene, which acquires a predominantly cumulus status, while orthopyroxene often occurs in large poikilitic crystals. The morphological and mineralogical characteristics of the anorthositic bodies suggest an origin by partial replacement of gabbroic cumulates. The ELMI chamber underwent several episodes of replenishment/mixing, which are especially evident in olivine gabbros by: (i) non-cotectic proportions of mineral phases; (ii) plagioclase showing normal, inverse, and oscillatory zoning; and (iii) the coexistence in the same sample of two populations of plagioclase and clinopyroxene that are distinct in terms of texture and chemistry. Our petrographic and mineralogical data indicate that the effects of infiltration metasomatism and mechanical mixing are stronger in gabbroic cumulates than in troctolites. Troctolite and olivine gabbro cumulates show a very narrow Mg# range (71–81) governed mainly by mafic phases. Harker diagrams indicate that the parent magma underwent increased olivine fractionation in a deep-seated magma chamber between episodes of replenishment. The parallelism of the REE patterns reflects the cogenetic nature of the studied cumulates, although the troctolites show a more fractionated pattern than the olivine gabbros (La_N/Yb_N = 2.71–8.3 and 0.89–1.76, respectively). The positive Eu anomaly is ubiquitous (Eu/Eu∗ = 1.15–4.7), reflecting the accumulation of plagioclase.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 105995"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940820","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":"Fluvial‒marine interactions and ichnofacies in the Ordovician Peninsula Formation, Hermanus, South Africa","authors":"Brian G. Jones ,&nbsp;Kerrie L. Bann","doi":"10.1016/j.jafrearsci.2026.106004","DOIUrl":"10.1016/j.jafrearsci.2026.106004","url":null,"abstract":"<div><div>A moderately deformed succession of the Ordovician Peninsula Formation in the syntaxis zone of the Cape Fold Belt is well exposed at Hermanus, some 120 km east-southeast of Cape Town in South Africa. The oldest deposits recognised at Hermanus represent a regressive shallow-marine prodelta succession of storm-redeposited sandstone, silty bioturbated sandstone and siltstone. Some clean sandstone beds show abundant fugichnia and other trace fossils characteristic of the <em>Skolithos</em> Ichnofacies. The presence of hummocky cross-stratification and evidence of longshore current activity indicates water depths were probably just below storm wave-base. Between storms, flocculation of organic-rich mud from buoyant hypopycnal plumes associated with river floods suggests a prodelta environment in front of the prograding Peninsula Formation fluvial succession. A ravinement surface, with at least 4 m erosional relief, between the marine and fluvial successions may have been induced by a drop in relative sea-level. The overlying fluvial succession shows sedimentary features typical of a bed-load dominated fluvial system with planar and trough cross-stratified sandstone and scattered pebbles. These form upward-fining cosets (4–8 m thick) of predominantly downstream-accreting macroforms that indicate deposition from high-energy channelised flows with up to 90° palaeocurrent variability between cosets. They represent a broad, braided to low-sinuosity, fluvial channel system that drained across a low slope towards the south-southeast. Based on correlation with the ‘Rooiels marker’ north of Hangklip, the shallow-marine and overlying fluvial successions at Hermanus may represent part of the lower Peninsula Formation, equivalent to part of the ‘Leeukop member’ in the Cape Peninsula.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 106004"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979504","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 lithological units and alteration minerals in volcanic rocks of Nkondjock, Littoral Region, Cameron using Sentinel-2 remote sensing satellite imagery and comprehensive fieldwork","authors":"Synthia Nguimatsia Tengomo ,&nbsp;Rodolph Loïque Azefack Mbounou ,&nbsp;Agnès Blandine Kamgang Tchuifong ,&nbsp;Amin Beiranvand Pour ,&nbsp;David Guimolaire Nkouathio","doi":"10.1016/j.jafrearsci.2026.106003","DOIUrl":"10.1016/j.jafrearsci.2026.106003","url":null,"abstract":"<div><div>Mapping lithology and hydrothermal alteration zones in tropical environments remains a challenge due to the dense soil cover, the vegetation and the high cost of advanced methods. This study aims to discriminate volcanic formations and map hydrothermal alteration in the Nkondjock region using Sentinel-2 imagery, a rapid and cost-effective approach. Nkondjock, located in the Nyong-Bayomen domain of the Central African Fold Belt in Cameroon (CAFB), is underlain by rocks forming the Cameroon Line (CL). The visible, near-infrared (VNIR) and short-wave infrared (SWIR) bands of the Sentinel-2 sensor were used in this work. Image processing is based on band ratios, band combinations, principal component analysis (PCA) and supervised and unsupervised classifications. These techniques enable us to distinguish between basic and acidic volcanic rocks, as well as intrusive and metamorphic rocks. PCA confirms the delimitation of lithological units, and classification into basalts, basanites, tephrites, phonolites and trachytes, as well as the boundaries between volcanic, plutonic and metamorphic rocks. Principal component image and spectral ratio analysis are used to map iron oxides (B4/B3), hydroxylated (B12/B11 and B11/B8A), clay (B11/B5), and carbonate minerals (B11/B2). The resulting maps facilitate the exploration of hydrothermal deposits in the Nkondjock region, and more specifically in the Ndomgang, soho, Ntoumbé, Ndjingang, Mile, Male, Makita, Sahe, Nkongmalang, Matoube, Kouedjou, Tam and Bindjen areas. Validation by confusion matrix, field observations and laboratory analysis confirms the effectiveness of Sentinel-2 data for lithological discrimination and mineral prospecting in tropical and subtropical environments.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 106003"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145897866","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":"Spatial heterogeneity of porosity and permeability in the Albian — Turonian Sarvak Formation, Coastal Fars, south of Iran","authors":"Parisa GholamiZadeh ,&nbsp;Mohammad Hossein Adabi ,&nbsp;Abbas Sadeghi","doi":"10.1016/j.jafrearsci.2025.105992","DOIUrl":"10.1016/j.jafrearsci.2025.105992","url":null,"abstract":"<div><div>The Sarvak Formation is one of the heavy oil reservoirs in the Zagros Orogenic Belt in southern Iran. This formation is primarily composed of the Late Albian-Turonian carbonates, with minor shales. This study focuses on the depositional facies, diagenetic history, and petrophysical properties, including porosity, permeability, and water saturation, of the Sarvak Formation integrated with wireline logs to evaluate the reservoir characterization and outline the primary controls on its significant heterogeneity. The reservoir quality is principally controlled by (1) Primary depositional texture and (2) subsequent diagenetic overprinting. The rudistic grain-supported facies, deposited in shallow, high-energy mid-ramp settings, inherently establish the highest quality zones. Conversely, mud-supported facies from inner/outer ramp environments show reduced quality. This primary control is significantly modified by secondary diagenetic processes—notably meteoric dissolution, dolomitization, and fracturing induced during burial—which collectively acted to enhance both porosity and permeability across the sequences. In the Coastal Fars sub-zone, the Sarvak Formation exhibits six third-order transgressive-regressive sequences. The integration of core data with wireline logs identified eight distinct Pore Facies (PFs) that dictate large-scale heterogeneity within this sequence stratigraphic framework. Critically, Pore Facies 2 (PF2), characterized by rudist and bioclastic grainstones/rudstones associated with reef/fore-reef environments, represents the optimum reservoir zone, displaying average porosity of 11.6 % and permeability of 21.37 md, primarily found beneath sequence boundaries (RSTs). In contrast, PFs 3, 5, 6, 7, and 8, located within Transgressive Systems Tracts (TSTs), function as moderate-low permeability units. The broader implication of this research is the development of a predictive model for reservoir spots. The results confirm that the most productive PFs (PF1, PF2, and PF4) are vertically associated with the upper sections of specific sequences (Sequence boundaries of Late Albian, Late Cenomanian, and Turonian). This stratigraphic framework provides a crucial predictive tool for enhanced reservoir characterization, suggesting that high-quality zones may thicken preferentially toward the northwest of the Coastal Fars sub-zone.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 105992"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940821","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":"Early human dietary heritage in Sub-Saharan Africa","authors":"Ana Maria Pinho Guina ,&nbsp;José Augusto Guina ,&nbsp;Filomena Anjos ,&nbsp;Jorge Ferrão ,&nbsp;Victoria Bell ,&nbsp;Tito Horácio Fernandes","doi":"10.1016/j.jafrearsci.2026.105998","DOIUrl":"10.1016/j.jafrearsci.2026.105998","url":null,"abstract":"<div><div>Ancient human food ways is a fundamental part of the history of humankind. Hominins’ evolution has paralleled major shifts such as the introduction of lithic devises, gain mastery over fire, cooking, fermentation, plant and animal domestication, which, in turn, have been associated with anatomical, physiological, cognitive, sociocultural, and behavioural shifts. A holistic understanding may shed light not only on how human diet evolved, but also on the mechanisms governing metabolism and prevalent metabolic syndromes in modern humankind. Food is essential for understanding human development, adaptation, environmental exploitation, cognition, technology, and survival, while adaptations to the habitat and lifestyle have led to changes in human genome from dietary transitions across hundreds of human generations. Ancient foods incorporate the complex milieu of phytonutrients in grains, native plants, mushrooms, fruits, legumes, nuts, honey, and seeds, being the nutritious building blocks of each heritage diet, essential for ensuring sustainable food security. Meat eating have played a major role mainly on brain size increase. What foods people ate in the past, how foods were prepared, and what does this disclose about daily lives, cultural values and social interactions, is a central data repository, and may give an indication of chronic disease prevention. The reconstruction of ancient diets is complex for many factors, including to the unpredictability of humans themselves. We address some cultural practices, dietary traditions, ancient diets and culinary practices, understanding the enormous variability among regional countries and the nutritional transition shift from hunter-gatherer societies to agricultural-based subsistence and present westernised diets. Integrating ancestral dietary wisdom does not necessarily mean strictly adhering to a primitive diet, but rather adopting core principles validated by modern science to reduce the risk of chronic diseases prevalent in modern society.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 105998"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979498","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":"Predictive study of tsunami impact on the southwestern Atlantic coast of Morocco","authors":"Mohamed Outiskt ,&nbsp;Soufiane Tichli ,&nbsp;Maria Ana Baptista ,&nbsp;Said El Moussaoui ,&nbsp;Khadija Aboumaria","doi":"10.1016/j.jafrearsci.2026.106025","DOIUrl":"10.1016/j.jafrearsci.2026.106025","url":null,"abstract":"<div><div>Tsunamis have historically affected the Moroccan Atlantic coast, resulting in significant human and socio-economic consequences. This study presents the first tsunami risk assessment specifically focused on the city of Agadir, a major urban and economic hub in southwestern Morocco. By simulating the 1755 Lisbon tsunami and evaluating its potential impact on Agadir, we fill a critical gap in the existing literature, which has largely overlooked this vulnerable coastal city. Agadir's dense urban fabric, thriving tourism sector, and strategic harbor make it particularly susceptible to tsunami-induced disruptions. We analyze four credible earthquake scenarios, previously identified in scientific literature as potential triggers of the 1755 event, using the NSWING (Nonlinear Shallow Water with Nested Grids) numerical simulation model. The results, visualized through high-resolution maps of maximum wave heights and inundation distances, reveal significant vulnerability, with wave heights ranging from 0.1 to 5.3 m and inundation distances reaching up to 310 m inland. These findings offer vital insight for local authorities and policymakers, providing a scientific foundation for enhancing tsunami preparedness, resilience strategies, and public awareness initiatives in Agadir.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 106025"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090710","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":"High-resolution geochemical characterization of source rocks for the Apollonia carbonate reservoir, East Razzak Field, Western Desert, Egypt: A solution to the origin controversy","authors":"Mohamed A. Agamy ,&nbsp;Mahmoud Y. Zein El Din ,&nbsp;Mohamed M. El Nady ,&nbsp;Walid A. Makled","doi":"10.1016/j.jafrearsci.2026.106032","DOIUrl":"10.1016/j.jafrearsci.2026.106032","url":null,"abstract":"<div><div>This study addresses the long-standing controversy regarding the source rocks for oil in the Apollonia carbonate reservoir of the East Razzak Field, Western Desert, Egypt. While previous research correlated the oil with the Jurassic Khatatba Formation, new geochemical evidence presents a conflicting hypothesis. We employed high-resolution geochemical characterization, including Rock-Eval pyrolysis, visual kerogen analysis, and gas chromatography-mass spectrometry (GC-MS), on samples from potential source rocks, including the Abu Roash and Khatatba formations, and compared them to the oil from the Apollonia reservoir. The present findings reveal that the Abu Roash F and G members, previously considered immature, are in fact thermally mature and oil-prone, with thermal alteration indices (TAI) and oxidation Tmax values indicating they are within the oil generation window. These elaborate new evidences that were not presented before in the record about East Razzak Field. The stable carbon isotope compositions and bulk geochemical parameters demonstrate that the Apollonia oils originated from a marine, medium-sulfur Type II kerogen source, specifically linking the hydrocarbons to the Abu Roash F and G members rather than the more terrigenous Khatatba or Alam El Bueib formations. The oil from the Apollonia reservoir exhibits a low Pristane/Phytane (Pr/Ph) ratio of less than 1.0, which is a strong indicator of an anoxic, marine depositional environment. This signature is consistent with the Abu Roash F and G members, which also exhibit low Pr/Ph ratios and a Type II kerogen classification. In contrast, the Khatatba Formation shows a different signature, with a Pr/Ph ratio greater than 1.0, suggesting a more oxidizing, mixed terrestrial and marine environment. The consistency of the biomarker signatures, particularly the Pr/Ph ratio, provides compelling evidence of a genetic link between the Abu Roash Formation and the Apollonia oil. This research resolves the origin controversy, establishes the Upper Cretaceous Abu Roash Formation as the main source rock, and refines our understanding of the petroleum system in the Razzak Field.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 106032"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034963","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":"Integration of ASTER remote sensing and gamma-ray spectrometry for mapping hydrothermal alteration in the Sirwa Massif, central Anti-Atlas, Morocco: A guide for mining exploration","authors":"Mohammed Jalal Tazi ,&nbsp;Mohammed Ouchchen ,&nbsp;Driss El Azzab ,&nbsp;Driss Benyahia ,&nbsp;Abdelhamid Bajadi ,&nbsp;Hafsa Boufakri ,&nbsp;Bouchra Dadi","doi":"10.1016/j.jafrearsci.2026.106019","DOIUrl":"10.1016/j.jafrearsci.2026.106019","url":null,"abstract":"<div><div>This study adopts a multidisciplinary approach integrating ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) satellite imagery and airborne gamma-ray spectrometry data using a GIS-based fuzzy logic model to delineate the spatial distribution and zonal patterns of hydrothermal alteration assemblages in the southern part of the Sirwa Massif in the central Anti-Atlas belt (Morocco). This area records a complex tectono-magmatic history associated with significant hydrothermal Au–Ag–Cu deposits, yet remains largely underexplored. ASTER remote sensing data were analyzed using Band Ratio (BR) and Crosta techniques, enabling the identification of phyllic, argillic, propylitic and iron oxides alteration zones. Additional gamma spectrometry data, including uranium (eU), thorium (eTh), potassium K (%) and the K (%)/eTh ratio, were used to define zones of potassic alteration closely associated with hydrothermal activity.</div><div>A GIS-based fuzzy logic approach was implemented to integrate ASTER-derived hydrothermal alterations and AGRS-based potassic alteration layers to generate a hydrothermal alteration prospectivity map, highlighting zones of high mineralization potential. Six highly prospective zones for hydrothermal mineralization were delineated, located at lithological boundaries between Ouarzazate Group volcano-sedimentary outcrops and Pan-African granodioritic complexes, and the overlying Paleozoic cover. These zones coincide with areas of high structural complexity associated with pre-existing E–W, ENE–WSW, and NE–SW fault systems. The latter, developed during the post-collisional stage of the Pan-African orogeny, which acted as conduits for hydrothermal fluids associated with alkaline to calc-alkaline magmas, forming extensive alteration halos.</div><div>The hydrothermal alteration prospectivity map was statistically confirmed using the (ROC-AUC) analysis, complemented by rigorous field validation. This confirms the high accuracy of the adopted mapping approach for delineating hydrothermal zones, consequently optimizing subsequent mineral exploration strategies within the Sirwa Massif.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 106019"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034980","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":"Structural study of the Chtouka Plain (Morocco) for hydrogeological implications: Insights from geological, remote sensing and geophysical data analysis","authors":"Sliman Hitouri ,&nbsp;Ibtissam Rezouki ,&nbsp;Mustapha Ikirri ,&nbsp;Siham Aouzal ,&nbsp;Mustapha Boujamaoui ,&nbsp;Mohamed Abioui ,&nbsp;Abdelouahed Essaied","doi":"10.1016/j.jafrearsci.2026.105997","DOIUrl":"10.1016/j.jafrearsci.2026.105997","url":null,"abstract":"<div><div>The Chtouka Plain, in central western Morocco, is facing a severe water crisis due to declining rainfall linked to climate change and increasing groundwater exploitation, particularly for agriculture. This situation has led to a significant drop in groundwater levels and growing concerns about seawater intrusion along the coast zone.</div><div>To address these issues, a multidisciplinary study intergrating geological, hydrogeological, and geophysical approaches was conducted. Remote sensing, GIS, and geophysical techniques such as Electrical Resistivity Tomography (ERT) and gravimetry were used to map lineaments, fault structures, and aquifer vulnerability. The main objective of this study is to identify the faults and lineaments affecting the area, as well as their contribution to groundwater circulation and aquifer recharge. The results reveal four dominant fault orientations (NE-SW, N-S, NW-SE, and E-W). Major structural features, such as the Western and Eastern Tiznit Faults, play a key role in controlling groundwater flow between deep and shallow aquifers. Indeed, the Cenomanian–Turonian aquifer, composed of fractured limestones and dolomites underlying Quaternary deposits, is identified as the main groundwater reservoir, offering high potential for sustainable water resource management.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 105997"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940819","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":"Palaeomagnetic investigation of Palaeoproterozoic dykes from Botswana","authors":"Kemiso Tshwenyego ,&nbsp;James King ,&nbsp;Adrian R. Muxworthy ,&nbsp;Liang Qi ,&nbsp;Moikwathai Moidaki","doi":"10.1016/j.jafrearsci.2025.105954","DOIUrl":"10.1016/j.jafrearsci.2025.105954","url":null,"abstract":"<div><div>The geomagnetic field including its intensity is poorly constrained during the Proterozoic era (2500–541 Ma). Understanding geomagnetic field behaviour during this long-time interval is key to understand the evolution of the Earth including dating the age of the Earth's inner core nucleation. Palaeointensity experiments suggest low magnetic field intensities during the Palaeoproterozoic era between (2500–1500 Ma). To address this issue, we present palaeodirectional and palaeointensity results conducted on three previously dated Palaeoproterozoic localities in Botswana: 1) the Moshaneng Complex gabbros (2054 ± 2 Ma), 2) the Moshaneng dolerite dykes (1927 ± 1.5 Ma), and 3) the Pilanesberg dolerite dykes (1347 ± 97 Ma). Virtual geomagnetic poles were obtained from all three localities. Only the Moshaneng dolerite dyke yielded a virtual dipole moment (VDM) of 2.4 ± 0.4 × 10²²Am² from the three studied sites, which is consistent with a dipole low during the Palaeoproterozoic era. The results show that during the Palaeoproterozoic era, there was low VDM recorded which is similar to other values obtained in similarly aged Palaeoproterozoic studies.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"236 ","pages":"Article 105954"},"PeriodicalIF":2.2,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979501","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}