Journal of African Earth Sciences最新文献

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

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

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

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

{"title":"Petrogenesis and geodynamics of clinopyroxenites in faryab metaultramafic sequence (south of Kerman province); Evidences for mantle heterogeneity in southern Iran","authors":"Mojtaba SoltaniNezhad ,&nbsp;Hamid Ahmadipour ,&nbsp;Abbas Moradian ,&nbsp;Kazuo Nakashima","doi":"10.1016/j.jafrearsci.2025.105753","DOIUrl":"10.1016/j.jafrearsci.2025.105753","url":null,"abstract":"<div><div>The Faryab ultramafic complex with Paleozoic age, located in the south east of Kerman province, Iran. Field evidences show that it has emplaced in the Bajgan metamorphic complex after metamorphosing the Bajgan units, and includes harzburgite, lherzolite, dunite, clinopyroxenite, and chromitite. Clinopyroxenite has intruded into the peridotites in the form of dykes and veins and their cumulate texture, indicate that these rocks have crystallized from silicate melts. Mineral chemistry reveals a mantle origin for them (Mg# of Cpx = 91–94) and their whole rock composition is not similar to MORBs and mantle-depleted peridotites (Ni up to 720 ppm and MgO = 32.4 wt%); however, they are depleted in LILE and LREE compared to HREE similar to well-known clinopyroxen asite cumulates. The whole rock chemical composition of Faryab clinopyroxenits (SiO2 = 50.67 and Cr = 6180 ppm) suggests that the parent magmas were probably Low-Ca boninitic melts. These boninites derived from the reaction between primary calcium rich picritic melts and the host peridotites and as they ascend through fractured lithospheric peridotites, leaving behind the Faryab clinopyroxenites. The parallel alternating of clinopyroxenites suggest that the upper mantle in this region likely rose diapirically, causing pressure reduction and partial melting of the upper mantle and resulted in the formation of parallel fractures in the lithosphere. The Faryab clinopyroxenites can be considered as channels through which the supra-subduction zone melts of the Neotethys lithosphere ascended and formed them as relatively high pressure cumulates. The presence of clinopyroxenites and their petrogenetic evolution provide undeniable evidence of upper mantle heterogeneity in south of Iran.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105753"},"PeriodicalIF":2.2,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144563490","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":"Interpretation of 40Ar/39Ar geochronological data to infer mineralization events in Archean terranes: Comment on Bineli Betsi et al. (2025)","authors":"H.M. Rajesh","doi":"10.1016/j.jafrearsci.2025.105752","DOIUrl":"10.1016/j.jafrearsci.2025.105752","url":null,"abstract":"<div><div>In spite of the wide use of ⁴⁰Ar/³⁹Ar geochronology of potassium-bearing minerals to date mineral deposits, caution needs to be exercised in the interpretation as there is a high chance that the ages have been modified by subsequent events not related to the mineralization. This comment addresses the contentious nature of the c.550 Ma ⁴⁰Ar/³⁹Ar hydrothermal K-feldspar ages from the Mowana copper deposit in NE Botswana, and used by Bineli Betsi et al. (2025) to invoke a much younger mineralization event not compatible with known geologic events within the host Archean terrane. Comparable U-Pb zircon lower intercept ages are widely reported from the different Archean terranes in the region, and shown to be a common result of sub-recent weathering-related Pb-loss. The highly disturbed nature of the ⁴⁰Ar/³⁹Ar spectra presented in Bineli Betsi et al. (2025) is a testament to the modification of the dated K-feldspar and the obtained ages are re-interpreted to indicate alkali redistribution related to weathering in the Archean hinterland. Instead, the Paleoproterozoic ages obtained by earlier studies from Pb-Pb sulphides are suggested to be closer to the timing of mineralization at the Mowana copper deposit.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105752"},"PeriodicalIF":2.2,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144563491","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":"Modelling geologic features and structures in the Middle and Lower Benue Trough of Nigeria from gravity and aeromagnetic data sets","authors":"Ezekiel Yenne,&nbsp;Chris Green,&nbsp;Taija Torvela","doi":"10.1016/j.jafrearsci.2025.105745","DOIUrl":"10.1016/j.jafrearsci.2025.105745","url":null,"abstract":"<div><div>Understanding subsurface structures is key to predicting the evolution of a basin and its resources. The Benue Trough is a mega-structure that has been moderately well studied, although a detailed regional subsurface study of the basin is lacking. Our aim in this study is to highlight and show clearly the subsurface geologic structures/features through 2D and 3D models. We used high-resolution aeromagnetic and gravity datasets to map and investigate geologic features and subsurface structural texture of the trough in 2 and 3 dimensions. We constructed geologic models in 2D from gravity and magnetic datasets and mapped basement faults, depth to basement, Curie, and Moho depths, and interpreted the crustal structure of the basin. Three well-defined basement fault systems were identified: NE-SW, NW-SE, and ENE-WSW. Based on basement fault kinematics through paleo-stress field interpretation, we showed that the basement faults evolved through plate tectonic activities at the earlier stage of the evolution of the trough. We then carefully modelled in 3D critical interfaces (basement surface, Curie isotherm, and Moho), where we estimated their depths and interpreted their morphologies. The average basement depth is 4.3 km and areas of basement lows are interpreted as sub-basins; these are suitable sites for the accumulation of sediments (depocentres) while the basement highs are considered basement uplifts and blocks. The Curie depth (the depth to the bottom of the magnetic layer) is relatively flat across the area while the Moho is uplifted directly under the basin. We observed the crust to be thinned directly under the basin which we attributed to extensional rifting processes. This study exposed the subsurface tectonic architecture of the trough and demonstrated its continental origin due to crustal rifting and extension, accompanied by faulting, Moho shallowing, magma emplacement, and crustal thinning and stretching.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105745"},"PeriodicalIF":2.2,"publicationDate":"2025-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548697","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":"Diagenesis of the Callovian-Kimmeridgian Antalo Limestone Formation, Blue Nile Basin, Ethiopia: Implications for characterizing hydrocarbon reservoir quality","authors":"Beksa Amente ,&nbsp;Balemwal Atnafu ,&nbsp;Solomon Kassa ,&nbsp;Gilamichael K. Domenico","doi":"10.1016/j.jafrearsci.2025.105750","DOIUrl":"10.1016/j.jafrearsci.2025.105750","url":null,"abstract":"<div><div>Understanding the diagenetic evolution of carbonate formations is essential for evaluating their reservoir potential. This study provides the first integrated analysis of the diagenetic process affecting the reservoir quality of the Callovian-Kimmeridgian Antalo Limestone Formation in the Blue Nile Basin. Extensive field investigations, including detailed section logging and rock sample collection, were conducted across the Dejen-Gohatsion traverse, Jemma, and Mugher areas. From the collected rock samples, 115 representative samples were selected for petrographic analysis to assess the key diagenetic processes controlling porosity and reservoir quality of the carbonate deposits. The analysis reveals that calcite cementation and dissolution are the most prominent porosity-reducing and enhancing diagenetic processes, respectively. Other processes such as compaction, dolomitization, silicification, bioturbation, micritization, and fracturing diagenetic processes have significantly influenced primary and secondary porosity development, and reservoir quality of the Antalo Limestone Formation. This study provides insight into the Antalo Limestone reservoir quality in the Blue Nile Basin. Moreover, it offers important baseline data to guide future exploration and advanced investigations aimed at re-evaluating the formation as a significant reservoir. It also enhances the current understanding of reservoir heterogeneity in Ethiopian Jurassic carbonates and contributes valuable insights for regional hydrocarbon exploration.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"230 ","pages":"Article 105750"},"PeriodicalIF":2.2,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517308","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":"Multi-disciplinary approach to evaluate hydrocarbon potential in the Bornu Basin, Northeastern Nigeria","authors":"Chekwube Nnamdi Didi ,&nbsp;Olawale Olakunle Osinowo ,&nbsp;Okey Eliseus Akpunonu ,&nbsp;Solomon Ekene Okeke","doi":"10.1016/j.jafrearsci.2025.105742","DOIUrl":"10.1016/j.jafrearsci.2025.105742","url":null,"abstract":"<div><div>The Bornu Basin, a sub-basin of the Chad Basin in northeastern Nigeria, has experienced extensive petroleum exploration activities, with 23 wells drilled; however, only two encountered sub-commercial gas volumes. This study integrates well log data, sequence and seismic stratigraphy, structural interpretation, and fault seal analysis to better understand reservoir extent, depositional environments, and hydrocarbon trapping mechanisms. Well log analysis reveals a stratigraphic sequence gently dipping from southwest to northeast. The lowermost Bima Formation (Albian), composed mostly of sandstone, reflects a fluvial to continental setting. The Gongila Formation consists of interbedded lithologies, thinning southwestward. The Fika Shale, marked by high gamma ray readings, serves as a thick, continuous seal. The Gombe Formation, with alternating sands and shales, indicates fluvial to shallow marine conditions. The sandy Kerri-Kerri Formation suggests a continental environment, while the Chad Formation comprises clays and shales with minor sandstones. Sequence stratigraphic analysis identified three third-order sequences. Reservoir evaluation in Bulte-1 and Kasade-1 wells identified three potential reservoir zones (Cha-Res-1, -2, -3) in the Kerri-Kerri, Gombe, and Gongila Formations; respectively. The Kerri-Kerri and Gombe Formations show better reservoir quality with good porosity (0.13–0.18) and net to gross (0.93–0.98); respectively, while the Gongila Formation is poorer due to higher shale content (0.150–0.157) and high-water saturation (0.99–1.00). Seismic data revealed complex faulting patterns like normal, listric, and reverse especially in deeper zones, along with possible igneous intrusions. Two anticlinal leads were identified. Fault seal analysis suggests moderate sealing capacity with a Shale Gouge Ratio of 0.22–0.35. Rose diagram, Fisher mean vector statistics and Bingham axial distribution analysis suggest that the faults are trending in Northeast-southwest direction.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"230 ","pages":"Article 105742"},"PeriodicalIF":2.2,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144518189","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":"Hysteresis and thermomagnetic characteristics of soils and rocks in eastern Botswana","authors":"Moikwathai Moidaki,&nbsp;RubeniT. Ranganai,&nbsp;James G. King","doi":"10.1016/j.jafrearsci.2025.105747","DOIUrl":"10.1016/j.jafrearsci.2025.105747","url":null,"abstract":"<div><div>Rock magnetic properties are integral to various applications, including palaeomagnetism, plate tectonics, geological interpretation, geoexploration, mining, forensics, and engineering. This study builds upon previous research on the magnetic susceptibilities of soils in eastern Botswana, focusing on key magnetic parameters such as the Curie temperature (Tc), determined in a nitrogen atmosphere, and hysteresis variables (coercive force: Hc, coercive remanence: Hcr, saturation remanence magnetisation: Mrs, saturation magnetisation: Ms). Thermomagnetic curves, measured from room temperature up to 700 °C, facilitated the classification of magnetic mineralogy and granulometry.</div></div><div><h3>Results</h3><div>reveal the presence of magnetic minerals such as hematite, magnetite, and pyrrhotite, with Curie temperatures approximately at 600 °C, 580 °C, and 200 °C, respectively. Hysteresis loops further support the dominance of magnetite-like phases in the soil samples. Both hysteresis and thermomagnetic data suggest magnetite as the primary contributor to the magnetic properties. Notably, thermomagnetic analyses of soils along the Ramatlabama to Ramokgwebana transect—crossing the Kaapvaal Craton, Limpopo Belt, and Zimbabwe Craton—offer potential for delineating the boundaries of these cratonic regions and associated orogenic belts. Thus, expanding research coverage across different terrains and geological settings would further enhance our understanding of crustal processes and magnetic mineral distributions invaluable for geological modelling and exploration for raw material deposits.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"231 ","pages":"Article 105747"},"PeriodicalIF":2.2,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144587738","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}