Journal of African Earth Sciences最新文献

{"title":"Groundwater resources investigation using geophysical method in crystalline basement and volcanic rock regions of countries belonging to the East African Rift Valley: A review","authors":"Musabbir Ahmed Khan ,&nbsp;Hiroyuki Nakayama ,&nbsp;Shinji Nakaya","doi":"10.1016/j.jafrearsci.2024.105432","DOIUrl":"10.1016/j.jafrearsci.2024.105432","url":null,"abstract":"<div><div>The East African Rift Valley (EARV) is characterized by diverse geology, including crystalline, volcanic, and metamorphic rocks, shaped by tectonic activity leading to complex faulting and fractured zones. These fractured zones in hard rock serve as crucial groundwater reservoirs, often explored using electric resistivity methods. Countries surrounding the EARV, such as Burundi, Djibouti, the DR Congo, Eritrea, Ethiopia, Kenya, Malawi, Mozambique, Rwanda, Tanzania, Uganda, and Zambia, share similar geological features linked to the rift system. Groundwater investigation in these regions, particularly using geo-electric resistivity methods, is essential for understanding subsurface geology, potential aquifers, and structural features, additionally, water quality, and dominant water sources of these countries are reviewed to categorize twelve countries based on the availability of the groundwater investigations and country status. The review results highlight some countries rely on weathered and fractured basement aquifers concentrated in specific areas, while others utilize aquifers associated with various geological settings and surface water as alternative sources due to the limited yield from basement complex aquifers. Therefore, 12 countries were classified broadly into three types, and a resistivity distribution map was created to visually show the present status of research and development works of the existence of gaps and limitations, which is generally in line with this comprehensive review. The outcomes of this study are useful for future research and sustainable development by informing the resistivity distribution trend and water resource usage in each country, as a result, expecting to contribute to the effective utilization of groundwater resources in the challenging crystalline basement and volcanic rock environments of the region.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105432"},"PeriodicalIF":2.2,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357222","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":"Flood risk decomposed: Optimized machine learning hazard mapping and multi-criteria vulnerability analysis in the city of Zaio, Morocco","authors":"Maelaynayn El baida ,&nbsp;Farid Boushaba ,&nbsp;Mimoun Chourak ,&nbsp;Mohamed Hosni ,&nbsp;Hichame Sabar ,&nbsp;Toufik Zahaf","doi":"10.1016/j.jafrearsci.2024.105431","DOIUrl":"10.1016/j.jafrearsci.2024.105431","url":null,"abstract":"<div><div>Urban flood risk mapping has become crucial for effective mitigation and urban planning. This study assesses and maps flood risk in the city of Zaio, Morocco, using machine learning and Multi-Criteria Decision Analysis (MCDA) techniques to overcome data scarcity challenges. We employed the Random Forest (RF) model with nine flood conditioning factors for flood hazard and the Analytical Hierarchy Process (AHP) for vulnerability assessment. To enhance RF model performance, we compared three hyperparameter tuning techniques: Bayesian Optimization (RF-BO), Genetic Algorithm (RF-GA), and Grid Search (RF-GS). RF-BO demonstrated superior accuracy in flood hazard modelling. Flood vulnerability was assessed using AHP, incorporating social and physical factors. The final flood risk map was produced by combining the RF-BO hazard model with the AHP vulnerability assessment. Results indicate that flood hazard in Zaio is significantly affected by factors such as topography and distance to rivers. Moreover, areas with high population density closer to rivers, especially in the south-western residential area, were found to be more exposed to flood risk. The findings highlight the utility of ML models, MCDA, and hyperparameter optimization in urban flood risk mapping, enabling the identification of high-risk urban areas that should be prioritized for flood protection efforts. This approach proves especially valuable in ungauged regions with limited hydrological data.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105431"},"PeriodicalIF":2.2,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357243","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":"Review of morphotectonic studies in the East African Rift System: Insights from legacy research to modern advances","authors":"Nahid D. Gani ,&nbsp;Tadesse B. Alemu ,&nbsp;Liang Xue","doi":"10.1016/j.jafrearsci.2024.105423","DOIUrl":"10.1016/j.jafrearsci.2024.105423","url":null,"abstract":"<div><div>The East African Rift System (EARS) is a prime example of continental rifting, characterized by its iconic topographic features, which are significantly shaped by the interplay of tectonic and climatic forces. This review synthesizes past decades of morphotectonic studies (recent studies) on the plateau landscapes of the EARS, focusing particularly on their interiors and margins, and highlights their crucial role in advancing our understanding of landscape evolution. The paper revisits the legacy of geologic research in the EARS and delves into recent morphotectonic studies that quantify the rates and patterns of plateau incision, exhumation, and uplift through advanced thermochronological and topographic analyses. Additionally, the review identifies key unresolved questions, such as the origins of the plateau topography–whether from volcanic activity or mantle plume influence and explores how these plateaus maintained high elevations during the humid Oligocene Epoch without significant incision. The recent work described in this paper alongside legacy perspectives, continues to refine our geological understanding of the EARS, with broader implications for studies worldwide.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105423"},"PeriodicalIF":2.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327032","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":"The first described Onchopristis Stromer, 1917, (Elasmobranchii: †Onchopristidae) from the marine Maastrichtian of Dakhla Formation, Western Desert, Egypt","authors":"Luigi Capasso ,&nbsp;Sayed Abdel Aziz ,&nbsp;Abdel Aziz Tantawy ,&nbsp;Mohamed Kamel Mousa ,&nbsp;Dalia Gamal Ahmed Wahba ,&nbsp;Gebely Abdelmaksoud Abu El-Kheir","doi":"10.1016/j.jafrearsci.2024.105415","DOIUrl":"10.1016/j.jafrearsci.2024.105415","url":null,"abstract":"<div><p>An exceptional hypertrophic batoid rostrum of exceptional size (TL = 146 cm) and four fragmentary rostral teeth collected from the marine Maastrichtian of the Dakhla Formation, Egypt. Both the macroscopic aspects (with the presence of a \"wood-like\" layer that covers the central part of the rostrum and the presence of skin denticles at the bases of the ventral face) and microscopic characters (presence of tessellated cartilage in the central part of the rostrum and of laminated cartilage in the peripheral areas of it) demonstrate that the rostrum belongs to a large specimen of the genus <em>Onchopristis</em> Stromer, 1917. The absence of complete rostral teeth prevents the establishment of a new species. Nonetheless, the described finds demonstrate, for the first time, that the genus <em>Onchopristis</em> persisted in the euryhaline areas of North Africa until the end of the Cretaceous.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105415"},"PeriodicalIF":2.2,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142241756","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":"Sequence stratigraphic and petrophysical controls on the oil-reservoirs architecture: A case study from the Cretaceous meqasequence, Gulf of Suez region, Egypt","authors":"Mohammad A. Sarhan ,&nbsp;Amer A. Shehata ,&nbsp;Mohamed I. Abdel-Fattah","doi":"10.1016/j.jafrearsci.2024.105412","DOIUrl":"10.1016/j.jafrearsci.2024.105412","url":null,"abstract":"<div><p>This research aims to perform a comprehensive examination encompassing sequence stratigraphy and petrophysical assessment of the Cretaceous meqasequence along the Gulf of Suez region. Through an investigation of eight wells, spanning both offshore and onshore fields in the Gulf of Suez Basin, the sequence stratigraphic analysis reveals a division of the Cretaceous meqasequence into two distinct depositional sequences: Early Cretaceous (SQ-1) and Late Cretaceous megasequence. The Early Cretaceous megasequence comprises the Nubia Sandstones, while the Late Cretaceous megasequence includes the siliciclastic/carbonate sediments found within the Raha, Abu Qada, Wata, and Matulla Formations (SQ-2, SQ-3, and SQ-4). The distribution of the Cretaceous megasequences across the study area highlights a significant variation in thickness from the onshore to the offshore regions of the Gulf of Suez. This variation is primarily attributed to tectonic forces that governed both the deposition and erosion of sediments over time. The lowstand systems tracts (LSTs) and highstand systems tracts (HSTs) within both Cretaceous megasequences are characterized by sufficient sand content, making them favorable reservoirs.</p><p>Conversely, the transgressive systems tracts (TSTs) are identified as potential reservoir rocks. The analysis of petrophysical properties across different Cretaceous reservoirs reveals that the Early Cretaceous fluvial megasequence exhibits superior reservoir qualities compared to its Late Cretaceous counterpart. However, the Late Cretaceous megasequence comprises reservoirs with multiple levels and diverse petrophysical characteristics. The study offers valuable insights into how petrophysical properties and sequence stratigraphy influence Cretaceous reservoir architecture. Examining the depositional environments and petrophysical evaluation enhances our understanding of reservoir quality and distribution. Furthermore, it guides future exploration activities in the mixed siliciclastic and carbonate multi-level intervals of the Gulf of Suez and nearby basins, aiding in identifying potential hydrocarbon zones and optimizing drilling strategies.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"219 ","pages":"Article 105412"},"PeriodicalIF":2.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164967","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":"Targeting high-potential mineral prospects in the Ezzhiliga region, Moroccan central massif, using spectral data from the ASTER sensor","authors":"Younesse EL Cheikh ,&nbsp;Ahmed Attou ,&nbsp;Lahsen Achkouch ,&nbsp;Younes Mamouch ,&nbsp;Toufik Khouya ,&nbsp;Adama Sangare ,&nbsp;Abdelhalim Miftah","doi":"10.1016/j.jafrearsci.2024.105410","DOIUrl":"10.1016/j.jafrearsci.2024.105410","url":null,"abstract":"<div><p>This research paper introduces a comprehensive methodology for assessing hydrothermal alteration zones and structural complexity in the Ezzhiliga region, situated in the Hercynian Central Massif of Morocco. The approach utilizes ASTER imagery as the primary data source. The main objectives were to identify and analyze these geological features and then create a potential map for mineral exploration by integrating fuzzy logic and fractal concentration area analysis. Band ratios (RBD) and principal component analysis (PCA) were employed to detect and map argillic, phyllic, propylitic, and iron oxide alteration zones. Additionally, structural lineaments were extracted from the PC1 imagery to understand the structural pattern of the survey area. The incorporation of hydrothermal alteration zones and structural lineaments was achieved through the application of a fuzzy logic model, resulting in the generation of a mineral favorability map. The fuzzy logic model was customized to combine hydrothermal alteration and lineaments density maps, effectively eliminating false spectral anomalies induced by various interference factors. This map was then analyzed using the fractal concentration-area (C-A) model, which separated the anomaly from the geological background and generated a final mineral potential map. Analysis of fractal concentration-area was employed to define thresholds with greater precision, enhancing the reliability of mineral prospectivity assessments. Furthermore, laboratory analyses were performed to verify the outcomes of the mineral potential map. The obtained results revealed a significant affinity with the field data and indicated that the highly prospective zones are perfectly limited in spatial extent and generally associated with the contact of the Zaër granitic pluton with the metamorphic host rock, except for the anomaly identified to the southeast of the study area, along a major NE-SW trending fault.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"219 ","pages":"Article 105410"},"PeriodicalIF":2.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142147894","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":"Fluid flow in the Katanga Supergroup: From Lufilian brittle tectonic stages to the post-Lufilian period (Democratic Republic of Congo)","authors":"Pascal Mambwe ,&nbsp;Damien Delvaux ,&nbsp;Stijn Dewaele ,&nbsp;Louis Kipata ,&nbsp;Philippe Muchez","doi":"10.1016/j.jafrearsci.2024.105414","DOIUrl":"10.1016/j.jafrearsci.2024.105414","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The metasedimentary rock succession of the Neoproterozoic-Cambrian Katanga Supergroup in the Central Africa Copperbelt shows evidence of several complex tectonic events. The deformation of this supergroup started from the tectonic inversion at about 570 Ma and lasted up to today, but reached paroxysm at ∼550 Ma. This long period was characterized by folding and faulting throughout multiple compressive and extensional events, which controlled the regional fluid flow on the one hand, and played an important role during formation of the stratiform to stratabound Cu-Co (Ni, U) deposits and the polymetallic Cu-Zn-Pb (Ag, Ge, Mo, Cd) vein type deposits on the other hand. Based on the structural analysis and paleostress reconstruction, coupled with fluid inclusion characterization from mineralized structures in rocks from the Nguba, Kundelungu and Biano Groups, this study demonstrates that the composition of hydrothermal fluids changed during brittle tectonic deformation during the Lufilian orogeny and subsequent uplift and post-Lufilian faulting.&lt;/p&gt;&lt;p&gt;During early brittle tectonic deformation along strike slip faults with sinistral and dextral movement related to a NE-SW transpression, the Cu-mineralizing fluid was hypersaline (27.9–31.1 eq. wt% NaCl) with moderate temperatures (Th = 128–216 °C). The subsequent Cu or Cu (Zn, Pb) mineralization formed within an E-W extensional stress regime, related to the late Lufilian orogenic collapse. The fluid inclusions present in the gangue minerals associated with this latter mineralization show a large range in Th (50–264 °C) and salinity (26.7–36.0 eq. wt% NaCl). The decrease in temperature is interpreted to be due to migration of the fluids at shallower depth in the subsurface after uplift and erosion of the orogen. The increased salinity of the fluid is related to the dissolution of evaporites, mainly NaCl. A second H&lt;sub&gt;2&lt;/sub&gt;O-NaCl-CaCl&lt;sub&gt;2&lt;/sub&gt; fluid with a homogenization temperature below 55 °C has also been found associated with this brittle stage and mineralization phase, but only in rocks belonging to the Kundelungu Group. A third mineralization phase, also characterized by Cu or Cu (Zn, Pb), formed during the post-Lufilian period within a NW-SE transpressional inversion regime. The fluid inclusion in the gangue minerals of this mineralization phase have a smaller range in homogenization temperature (Th = 37–172 °C) and the largest range in salinity (0.71–30 eq. wt% NaCl), compared to the earlier fluid inclusions generations. This large range in salinity may be explained by the mixing of a high salinity fluid, already present during the earlier tectonic stages in the sedimentary basin, with meteoric water. During the more recent rift-related extension, a fluid with again a large and higher range in homogenization temperatures (Th = 47–257 °C) and with a typical low salinity (&lt;10 eq. wt% NaCl) has been recognized in minerals filling NNE-SSW to NE-SW oriented faults and fractures. The u","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105414"},"PeriodicalIF":2.2,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142172452","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":"Morphometry of the Mt Manengouba volcano: Insights into tephrostratigraphy of Eboga maars (South West Cameroon)","authors":"Amad Samir Mounpen Njiemessa ,&nbsp;Moussa Nsangou Ngapna ,&nbsp;Monespérance Germain Marie Mboudou ,&nbsp;Moïse Christian Balla Ateba ,&nbsp;Pascal Landry Wabo Defo ,&nbsp;Dieudonné Youmen ,&nbsp;Sébastien Owona","doi":"10.1016/j.jafrearsci.2024.105411","DOIUrl":"10.1016/j.jafrearsci.2024.105411","url":null,"abstract":"<div><p>The GIS-based geomorphological and morphometric approaches were combined with field- and tephrostratigraphic analyses to reconstruct the history of the Mt Manengouba volcano including the Eboga maars in the southwestern part of the Cameroon Volcanic Line (CVL). The elevation, slope, relative relief, topographic position and terrain ruggedness indexes from the Digital Elevation Model (DEM, 12.5 m) were determined to constrain two main geomorphic units corresponding to the Elengoum and Eboga nested stratovolcanoes which were affected by differential erosional processes. The studied grain size, shape, vesicularity, structure, degree of lithification, sorting, thickness, grading patterns, sedimentary features, spatial distribution revealed three tephrostratigraphic units: U1 (U_1-1, lithic and juvenile; U_1-2 dominantly juvenile), U2 (U_2-1 ash- and juvenile rich-deposits; U_2-2, juvenile-scoria with few lithic) and U3 (scoria cone deposits). The total volume of ∼0.199 km³ of tephra deposits ranges the Eboga maars volcanoes within the small-volume monogenetic types. These results revealed dry/wet phreatomagmatism and strombolian activity as a contribution to the seven phases-eruptive history of the Mt Manengouba volcano: the pre-Manengouba; emplacement of Elengoum stratovolcano; collapse of Elengoum summit and formation of Elengoum caldera; emplacement of Eboga stratovolcano; the collapse of Eboga summit and formation of Eboga caldera; a phreatomagmatic phase and emplacement of Female and Male maars ending with an explosive stage associated with the formation of scoria and parasitic cones.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"220 ","pages":"Article 105411"},"PeriodicalIF":2.2,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1464343X24002449/pdfft?md5=cddc54edcbceda16270840a00e77c8f5&pid=1-s2.0-S1464343X24002449-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142162902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated seismic, petrophysical, and geochemical studies for evaluating the petroleum system of the Upper Bahariya-Abu Roash G sequence in the Karama Field, Abu Gharadig Basin, North Western Desert, Egypt","authors":"Neamat Aboelhassan ,&nbsp;Elhamy Tarabees ,&nbsp;Mohamed El Bastawesy ,&nbsp;Saad Mogren ,&nbsp;Bassem S. Nabawy ,&nbsp;Elkhedr Ibrahim ,&nbsp;S.M. Talha Qadri","doi":"10.1016/j.jafrearsci.2024.105413","DOIUrl":"10.1016/j.jafrearsci.2024.105413","url":null,"abstract":"<div><p>The main aim of this study is to delineate the hydrocarbon potential and evaluate the petroleum system elements of the Cenomanian Abu Roash G (AR/G) and the Upper Bahariya Members in the Karama Field. It lies at the southeast borders of the Abu Gharadig Basin, a well-known basin in the W.D. to the NE of Africa. We accomplish this study by analyzing a total of thirty 2D seismic profiles, a complete data set of well logs for five wells, and their geochemical data. The workflow starts with illustrating the dominant subsurface structural features, defining the main potential reservoirs and their parameters, and checking the maturity of the probable source rocks. The seismic interpretation indicated that the research area had been influenced by a NE-SW anticlinal structure accompanied by a set of WNW-ESE and NW-SE normal faults that are controlled by the positive compression inversion process that dominated during the Late Cretaceous. Analyzing and processing the well log data sets suggest that the reservoirs of the Abu Roash G (AR/G) and the Upper Bahariya Members are characterized by poor to good reservoir settings with net-pay thickness reaching up to 13–50 feet in the different wells (av. Effective porosity (<em>∅</em>_<em>eff</em>) = 17.7 % and 15.6% for the AR/G and the Upper Bahariya Members, av. Shale volume (<em>Vsh</em>) = 17.4 % and 13.6 %, av. Water saturation (<em>Sw</em>) = 38.9 % and 39.8 %, while av. Hydrocarbon saturation values (<em>So</em>) = 60.2 % and 61.1%, respectively). The geochemical and maturity analyses assisted in determining the potential mature source rocks of the Jurassic Khatatba Shale (<em>TOC</em> = 0.70–5.67%; <em>S</em>_<em>1</em><em>+S</em>_<em>2</em> = 0.43–5.97 mg/g, <em>Ro</em> = 0.54–1.06 %) with some contribution from the Cretaceous sources (Alam El-Bueib and Bahariya Formations). Studying elements of the petroleum regime of the Karama Field indicates that the trapped hydrocarbons are structurally controlled by three-way dip closures, horst blocks, sealing faults, and vertical sealing by impervious shale and limestone beds. This case study could be applied to similar analogs in other oil fields in the Egyptian Western Desert to delineate their hydrocarbon potential and structural setting.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"219 ","pages":"Article 105413"},"PeriodicalIF":2.2,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142129305","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":"Thermal studies on the lower Carboniferous basins of Khenifra and Qasbat-Tadla, Morocco: What do they teach us about the pre-Variscan stages in NW Africa?","authors":"R. Leprêtre ,&nbsp;M. El Houicha ,&nbsp;A. Schito ,&nbsp;R. Ouchaou ,&nbsp;F. Chopin ,&nbsp;P. Cózar","doi":"10.1016/j.jafrearsci.2024.105406","DOIUrl":"10.1016/j.jafrearsci.2024.105406","url":null,"abstract":"<div><p>Within the Variscan Belt of Morocco, the Central Massif preserves Early Carboniferous rift basins. The Lower Carboniferous Khenifra and Qasbat-Tadla basins are aborted rifts, developed just before the Variscan orogenesis in Morocco that occurred during the Pennsylvanian-Cisuralian in NW Africa. Due to both weak inversion of these basins during the Variscan orogeny and limited burial afterwards, these basins offer the opportunity to study the Early Carboniferous pre-orogenic thermal regimes. In the Khenifra basin, 77 samples collected across the basin and its basement's boundaries, allowed the determination of the maximal temperature reached during the rocks burial by means of Raman spectroscopic analyses. The Ordovician basement shows mean temperatures between 230 and 300 °C whereas the upper Visean/Serpukhovian infill has a wide range, from temperatures &lt;160 °C to 250–260 °C. This thermal variation within the basinal series has been evidenced from west to east and cannot have been acquired during the Variscan events. The acquisition of these maximal temperatures occurred between Late Devonian to Upper Visean/Serpukhovian and is thought to result from the formation of an extended rift. In the Qasbat-Tadla basin, Rock-Eval data from Ordovician to Devonian source-rocks indicate significantly lower maximal temperatures reached by pre-Carboniferous samples that are within the oil window. Our results are in favor of a heterodox model for the Variscan belt in Morocco and NW African in general, suggesting that no pre-Variscan compressional events are needed. Instead, the development of the intraplate Variscan belt in NW Africa was permitted through the development of hot and weak Lower Carboniferous basins, subsequently inverted in a far-field stress field. The striking thermal differences between the Khenifra and Qasbat-Tadla basins suggest that important tectonic segmentation must have shaped the area during the Early Carboniferous extensional phase.</p></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"219 ","pages":"Article 105406"},"PeriodicalIF":2.2,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1464343X24002395/pdfft?md5=86b392077930dd25ae2e2e61ee1778a3&pid=1-s2.0-S1464343X24002395-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}