Journal of African Earth Sciences最新文献

{"title":"Revising the lithostratigraphic framework of the Ediacaran succession of the Anti-Atlas belt: correlation across the Cadomian domain of the West African Craton","authors":"Jamal El Kabouri ,&nbsp;Antoine Triantafyllou ,&nbsp;Ezzoura Errami ,&nbsp;Said Belkacim ,&nbsp;Emma Calassou ,&nbsp;Amal Zouicha ,&nbsp;Ulf Linnemann","doi":"10.1016/j.jafrearsci.2025.105696","DOIUrl":"10.1016/j.jafrearsci.2025.105696","url":null,"abstract":"<div><div>In the northern margin of the West African Craton (WAC), Ediacaran terranes crop out in the Anti-Atlas and the peri-Gondwanan terranes of the Meseta and the Ossa-Morena Zone of Western Europe. In the latter, the ca. 640-530 Ma Cadomian evolution is well understood, whereas geodynamic events effected terranes in Morocco remain debated, partly due to imprecise lithostratigraphic units and their ages. In this study, we integrate new field surveys with available geochronological and isotopic data to refine the lithostratigraphy of the Anti-Atlas and establish an across-orogen correlation with the Meseta and the Ossa Morena Zone (Spain).</div><div>The lithostratigraphic revision suggests that the Ediacaran succession of the Anti-Atlas can be subdivided into the early Ediacaran Saghro Group (640–600 Ma) and the late Ediacaran Ouarzazate Supergroup (580–538 Ma), separated by a 20-million-year (Ma) sedimentary gap. The Ouarzazate Supergroup is further subdivided into three groups: M'Gouna, Lower Ouarzazate, and Upper Ouarzazate, each characterized by distinct isotopic signatures and separated by two angular unconformities.</div><div>This new lithostratigraphic framework shows that the Eastern-Central Anti-Atlas (ECAA) and Meseta preserve an early Ediacaran sedimentary and volcano-plutonic infill of a subsiding back-arc basin that developed between 640 and 600 Ma. This early Ediacaran back-arc succession is also present in Ossa Morena Zone but is absent in the western Anti-Atlas, which remained tectonically stable during this period. The closure of this basin was marked by tectonic-metamorphic and magmatic activity, as evidenced by the deformation of the Saghro Group in the ECAA and Meseta and the Montemolín Formation in Ossa Morena, accompanied by the emplacement of adakitic and magmatism with high Sr/Y signature. Throughout the Anti-Atlas and the Meseta area, this phase was followed by a magmatic and sedimentary gap of approximately 10 Myr and 20 Myr, respectively. After these hiatuses, sedimentation transitioned to a subaerial continental environment with deposition of the M'gouna Group between 580 and 570 Ma with sedimentary and magmatic rocks characterized by negative εNd values indicative of West African Craton (WAC) continental crust recycling. The Lower Ouarzazate Group (LOG, 569–567 Ma) was deposited over ∼2 Ma across the entire Anti-Atlas and Meseta, coinciding with a shift toward a more juvenile magma source. The Upper Ouarzazate Group (UOG, 567–540 Ma) is dominated by sedimentary, epiclastic deposits with exclusively juvenile magma.</div><div>This revised lithostratigraphic framework highlights a similar evolutionary history between the CEAA, Meseta, and Ossa-Morena Zone and sheds new light on the effects of the Cadomian orogeny on the Gondwana mainland.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105696"},"PeriodicalIF":2.2,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072225","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":"Community structure of the late Cenomanian Neolobites vibrayeanus bioevent in the Batna Mountains (Northeastern Algeria)","authors":"Samira Mendir ,&nbsp;Sihem Salmi-Laouar ,&nbsp;Riadh Aouissi ,&nbsp;Gamal Mohamed El Qot ,&nbsp;Mohamed S. Ahmed ,&nbsp;Ahmed Awad Abdelhady","doi":"10.1016/j.jafrearsci.2025.105681","DOIUrl":"10.1016/j.jafrearsci.2025.105681","url":null,"abstract":"<div><div><em>Neolobites vibrayeanus</em> (d'Orbigny) is a well-known bioevent in North Africa and the Middle East. It is equivalents to the marker early-late Cenomanian <em>Calyoceras guerangeri</em> biozone (∼95.2–94.8; my = 400ky). This well-dated event was used to analyze minor variations in the macrobenthic communities within Algeria's Batna Mountains. In the study area, the <em>Neolobites</em> bioevent is often accompanied by the nautiloid <em>Angulithes mermeti</em> (Coquand). Quantitative analyses of the benthic fauna from four sections indicated gradual changes in the composition and function of the macrobenthic faunal community. These vertical faunal changes coincide with the stocking pattern of a fourth-order (20-m thick) depositional cycle. Epifauna and suspension feeders decreased gradually and reached a minimum at the maximum flooding surface (mfs), while infauna and deposit-feeders such as irregular echinoids increased and reached a peak at the mfs. Diversity indices show gradual biodiversity decrease and dominance increase upward, which was attributed to deepening, flourishing of the irregular echinoids, and increasing bulldozing activities. These activities may have resulted in a soft substrate, where epifaunal taxa were negatively affected. In contrast to significant vertical faunal changes, geographic variations were minor suggesting lateral extent of similar environmental setting, and thus, the stratigraphic features of this bioevent have been simultaneously recorded. Our analysis reveals that faunal shifts extend beyond sequence boundaries, particularly during late TST and early HST, highlighting the effectiveness of biosequence stratigraphy in low-energy environments with minimal lithofacies variation.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105681"},"PeriodicalIF":2.2,"publicationDate":"2025-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071197","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":"Hydrogeophysical investigation for delineating groundwater aquifers in the Nabaa Al Hammara area, Wadi El Natrun, Egypt","authors":"SultanA.S. Araffa ,&nbsp;Hassan H. El-Kadi ,&nbsp;Abbas M. Abbas ,&nbsp;Ahmed M. Al Dabour ,&nbsp;Mahmoud S. Awad ,&nbsp;Mahmoud Zayed","doi":"10.1016/j.jafrearsci.2025.105684","DOIUrl":"10.1016/j.jafrearsci.2025.105684","url":null,"abstract":"<div><div>This study integrates geophysical and hydrochemical methods to map and identify freshwater-saturated zones and water quality within the study area. A total of twenty-four Vertical Electrical Sounding (VES) stations were deployed to determine key aquifer parameters, such as thickness and true resistivities. Seven Time Domain Electromagnetic (TEM) stations were also surveyed to corroborate the VES results. Well-logging analysis was conducted in seven boreholes distributed across the study area. Hydrochemical analysis of seven water samples was carried out to assess cations, anions, water type, and water quality ratios. The combined interpretation reveals the presence of three distinct aquifers at varying depths. The first aquifer, located between 60 and 70 m, exhibits resistivity values ranging from 11.5 to 68 Ω-meters and is characterized by freshwater quality. The second aquifer is found at depths of 100–115 m, with resistivities between 6.9 and 52 Ω-meters. The third, or deep aquifer, lies at depths of 180–200 m, with a 155–203 m thickness and resistivity values ranging from 6.5 to 62 Ω-meters. These aquifers show high potential, with a transmissivity (Tp) of 851 m²/day and conductivity values between 13.5 and 14.9 m/day. Hydrochemical analysis reveals that sodium chloride (NaCl) is the dominant water type.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105684"},"PeriodicalIF":2.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143929498","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":"Concentrations, distribution, and source appointment of heavy metal/loids in non-clastic sedimentary rocks: a case study of early jurassic chert, northeastern türkiye","authors":"Çiğdem Saydam Eker ,&nbsp;Abdullah Kaygusuz ,&nbsp;Uğur Volkan Arı","doi":"10.1016/j.jafrearsci.2025.105677","DOIUrl":"10.1016/j.jafrearsci.2025.105677","url":null,"abstract":"<div><div>The Current study used geochemical indicators such as the geo-accumulation index (<em>Igeo</em>), the Enrichment Factor (EF), and the contamination factor (CF) to evaluate the regional distributions and accumulations of various heavy metal/loids (HM; Co, Mo, Pb, Zn, Cu, Ni, As, Cd) in early Jurassic cherts in the Gümüşhane (NE Türkiye). Five stratigraphic section measurement (MS) areas (Tedaş, Alemdar, Akçakale, Tekke, and Pirahmet) and one borehole (Eskibağlar well) were selected for sampling. Major and trace element compositions of the selected 25 samples were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Calculated geochemical indexes indicated that Alemdar, Tekke MS, and Eskibağlar well samples were polluted with Pb, Zn, Cu, As, and Cd, Tedaş, Akçakale, and Pirahmet MS samples were polluted with Cd. Pearson's correlation coefficient (PCC) and principal component analysis (PCA) suggested that Zn, Pb, and Cu contaminating the Alemdar, Tekke MS, and Eskibağlar well samples were of ore mineralization origin, As was of terrigenous input, and Cd was probably of diatom origin. PCC and PCA showed that the Cd contaminating the Tedaş, Akçakale, and Pirahmet MS samples was probably of diatom origin, and the other metals found at normal levels in the samples were due to terrigenous input. The Early Jurassic period, which was a rift environment in the Gümüşhane region, is thought to have produced the cherts of the Alemdar, Tekke MS, and Eskibağlar well samples in a graben environment, while the cherts of the Tedaş, Akçakale, and Pirahmet MS were deposited in a horst environment. δU values, Ni/Co, and Vi/(V + Ni) ratios indicated that oxic-anoxic conditions were generally prevalent in the depositional environment, but redox conditions did not affect the abundance and distribution of HMs. These findings provide critical information for assessing heavy metal/loid enrichment and contamination potential not only in clastic sedimentary rocks, river sediments, and soils but also in non-clastic sedimentary rocks.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105677"},"PeriodicalIF":2.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941541","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":"Pliocene-Lower Pleistocene high-resolution foraminiferal biostratigraphy of offshore eastern Nile Delta area, Egypt","authors":"Mahmoud F. Khalifa ,&nbsp;Abdel Galil A. Hewaidy ,&nbsp;Amr Talaat ,&nbsp;Youssef Bazeen","doi":"10.1016/j.jafrearsci.2025.105679","DOIUrl":"10.1016/j.jafrearsci.2025.105679","url":null,"abstract":"<div><div>This study presents a high-resolution foraminiferal biostratigraphic analysis of three Pliocene-Lower Pleistocene successions encountered in the Andaleeb-1, Temsah-NW-10, and Barboni-NW-1 wells, drilled for gas exploration in the offshore eastern Nile Delta. The studied successions were divided into two rock units from base to top: The Kafr El-Sheikh Formation and the El-Wastani Formation. The studied successions are characterized by scarce planktonic foraminiferal records in most parts, while benthonic foraminifera are more abundant and diverse, particularly in the top portion of the investigated sections. The biostratigraphic analysis of the recorded foraminiferal assemblages suggests six planktonic foraminiferal zones and three benthonic foraminiferal zones based on marker species consistent with Mediterranean basin standards. The planktonic zones, in ascending order, are the NPP-1 (Nile Delta Pliocene Planktonic) Zone, NPP-2 Zone, NPP-3 Zone, NPP-4 Zone, NPSP-1 (Nile Delta Pleistocene Planktonic) Zone, and NPSP-2 Zone. The three benthonic zones, also in ascending order, are the NPB-1 (Nile Delta Pliocene Benthonic) Zone, NPB-2, and NPSB-1 (Nile Delta Pleistocene Benthonic) Zone. However, the reliability of some bioevents used to define the zonal boundaries was challenged by the scarcity and patchy distribution of certain marker species in the study area. The <em>sphaeroidenellopsis</em> acme, a key marker for the NPP-1 Zone, could only be tentatively recognized in one well because the bottom Pliocene is not encountered in the other two wells. The limited occurrences of <em>Globorotalia bononiensis</em>, the marker species for the subdivision of the standard Mediterranean MPL-5 Zone, complicated the correlation of the NPSP-1 Zone with the Mediterranean standard zonation. As a result of bio-zonation, an unconformity surface was recorded between the Lower Pliocene (Zanclean stage) and the Lower Pleistocene (Gelasian stage) due to totally or partially absence of Piacenzian stage. The onset of the Gelasian stage (Lower Pleistocene) is marked by the progradation of the Nile Delta, which led to the development of nutrient-rich, shallow marine environments, supporting a relatively diverse and abundant benthonic foraminiferal assemblage.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105679"},"PeriodicalIF":2.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143932240","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":"Corrigendum to “Quantitative biostratigraphy of the Miocene-Pleistocene succession in Sapphire field, offshore Nile Delta, Egypt” [J. African Earth Sci. 211 (2024) 1–14 105163]","authors":"Walid G. Kassab ,&nbsp;Ahmed A. Abdelhady ,&nbsp;Rehab Y. Helmy ,&nbsp;Mohamed S. Hammad ,&nbsp;Ahmed Zakaria ,&nbsp;Mohamed S. Ahmed ,&nbsp;Fatma Shaker","doi":"10.1016/j.jafrearsci.2025.105678","DOIUrl":"10.1016/j.jafrearsci.2025.105678","url":null,"abstract":"","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"228 ","pages":"Article 105678"},"PeriodicalIF":2.2,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143929291","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":"Mineral chemistry, ASTER hydrothermal alteration mapping, and geotechnical characterization of granitic rocks of the Arabian-Nubian Shield; A case study from Wadi El-Hima, South Eastern Desert, Egypt","authors":"Ahmed M. Abdel-Rahman ,&nbsp;Hisham A. Gahlan ,&nbsp;Mahmoud L. Abdel Latif ,&nbsp;Mahmoud H. Elyaseer ,&nbsp;Jason B. Price ,&nbsp;Mokhles K. Azer","doi":"10.1016/j.jafrearsci.2025.105683","DOIUrl":"10.1016/j.jafrearsci.2025.105683","url":null,"abstract":"<div><div>In this study of Wadi El-Hima granites, we present the results of petrographic, whole-rock chemistry, and mineral chemistry (microprobe) characterization; hydrothermal alteration mapping using ASTER data; and physico-mechanical (geotechnical) characterization, including suitability of using these granites for dimension and decorative stone. Our geological and petrographical results indicate that Wadi El-Hima contains four types of granitoids, divided into approximately coeval suites: an older granodiorite and trondhjemite suite, and a younger syenogranite and alkali feldspar two-mica granite suite. Despite the difference in relative ages, all phases exhibit high-K calc-alkaline to weakly peraluminous signatures except for alkali feldspar granite that ranges in affinity from metaluminous to peralkaline. Trondhjemite is an unusual HREE-enriched peraluminous granitoid placing it into a novel category comprising &lt;3 % of global granitoids. The tectonic origin of the older granodiorite-trondhjemite suite most closely resembles volcanic arc granite, in particular, I-S-type granite, whereas the younger syenogranite-alkali feldspar two-mica granite suite trends toward within-plate granite and A-type granite. Remote sensing mapping of hydrothermal alteration using ASTER relative band depth, band ratio, and mineral indices indicate that epidote, chlorite, carbonate, and sericite comprise the predominant alteration phases, whereas kaolinite and iron oxides comprise minor phases. Physico-mechanical test results show that bulk density ranges from 2.56 g/cm³ (syenogranite) to 2.72 g/cm³ (granodiorite). Water absorption ranges from 0.15 % (trondhjemite) to 0.22 % (alkali feldspar granite). Uniaxial Compressive Strength ranges from 50.9 (granodiorite) to 141 MPa (trondhjemite). The modulus of rupture and flexural strength of all the granites have similar ranges of 3.8–10.8 MPa and 3.2–8.9 MPa, respectively. All four rock types passed the minimum physical requirements (bulk density, water absorption, apparent porosity) of ASTM C20 and 97 tests, but, owing to mechanical flaws, failed the minimum mechanical requirements (Uniaxial Compressive Strength, Modulus of Rupture, and Flexural Strength) of ASTM C170, 99, 880, and 615 tests. Accordingly, Wadi El-Hima granitic rocks have low suitability for load-bearing construction applications but moderate to high suitability for non-load-bearing decorative applications, such as countertops and wash basins. This paper reflects global efforts to characterize the suitability of granites for use as dimension and decorative stone and to link such findings to petrochemical and remote sensing results.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105683"},"PeriodicalIF":2.2,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948116","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":"Petrographical and geochemical insights into gabbroic rocks in ophiolitic occurrences from Kınık-Kütahya (Türkiye)","authors":"İrem Aksoy,&nbsp;Gürsel Yanık","doi":"10.1016/j.jafrearsci.2025.105686","DOIUrl":"10.1016/j.jafrearsci.2025.105686","url":null,"abstract":"<div><div>The ophiolitic rocks within the Tavşanlı zone offer valuable insights into the closure period of the Neotethys and subsequent geological processes. This study focuses on the petrographic and geochemical characteristics of gabbroic rocks from the Kınık Ophiolite in Kütahya, Turkey. Petrographic observations show that the main constituents of gabbroic rocks are plagioclase (labradorite, bytownite), orthopyroxene, clinopyroxene, and hornblende. Hydrothermal alterations such as uralitization, chloritization, and carbonization are commonly observed in ophiolitic rocks. The mafic rocks are part of a differentiated tholeiitic magma series, emphasizing their co-magmatic evolution within the context of the ophiolitic complex. Despite variations in Large Ion Lithophile Elements (LILEs; K, Sr, Rb, and Ba) due to low-temperature hydrothermal alteration (e.g., saussuritization of plagioclase, uralitization of pyroxene, and chlorite–prehnite vein formation), the geochemical signature of the Kınık gabbroic rocks suggests island arc tholeiitic (IAT) characteristics. Additionally, their rare earth element (REE) patterns strongly indicate a supra-subduction zone (SSZ) affinity. The development of the Kınık ophiolite, involving magmatic crystallization, occurred during the final stages of island arc evolution in the Neotethyan Ocean within a supra-subduction, fore-arc tectonic setting.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105686"},"PeriodicalIF":2.2,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924535","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":"Hydrogeochemical properties of Çal Cave and its vicinity: Development and consequences of karstification in Düzköy (Trabzon, NE Türkiye)","authors":"Hilal Alemdağ ,&nbsp;Fatih Köroğlu ,&nbsp;Arzu Fırat Ersoy ,&nbsp;Aysel Şeren ,&nbsp;Zeynep Öğretmen Aydın ,&nbsp;Ali Erden Babacan","doi":"10.1016/j.jafrearsci.2025.105680","DOIUrl":"10.1016/j.jafrearsci.2025.105680","url":null,"abstract":"<div><div>Çal Cave, through which an underground river runs, was formed through the karstification of the neritic limestones that make up the Şahinkaya Formation, located between the neighbouring districts of Çayırbağı and Çalköy in Düzköy (Trabzon). The purpose of this study was to analyse the hydrogeochemical characteristics of samples collected from Çal Cave and the waters believed to supply it to determine their potential origins. Water samples were collected from nine locations during the wet and dry periods. After measuring the physical parameters of the samples, major anion–cation and trace element analyses were performed. When the parameters were compared with both WHO and Turkish standards, it was determined that they were within the limit values specified in the relevant regulations. Schoeller and Piper diagrams suggest that these waters are fed by the same origin and can be classified as a Ca-HCO₃ water type. Water-saturated zones were identified through electrical resistivity tomography sections that analysed the areas around the sampling sites. Finally, a comparison of the water quality data of water samples from Çal Cave during the dry season, published by Ofluoğlu in 1993, and this study's dry season water quality data revealed a decrease in the concentrations of Ca²⁺, Mg²⁺, K⁺, Cl⁻ and SO₄²⁻. The reason for this decrease over the past 29 years is likely the increased number of entryways where surface waters feed the cave.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105680"},"PeriodicalIF":2.2,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143937701","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":"Neogene sedimentary evolution and biostratigraphy of the Kasaba and Aksu-Gebiz basins in the eastern Mediterranean: Insights from paleontology and Sr isotope stratigraphy","authors":"Ahmet Can Akıncı ,&nbsp;Nusret Nurlu ,&nbsp;Ulvi Can Ünlügenç ,&nbsp;Deniz İbilioğlu ,&nbsp;Hande Sonsun","doi":"10.1016/j.jafrearsci.2025.105674","DOIUrl":"10.1016/j.jafrearsci.2025.105674","url":null,"abstract":"<div><div>The Kaş-Kasaba and Aksu-Gebiz basins are two important Neogene basins in the Eastern Mediterranean, flanking the Gulf of Antalya in southwestern Anatolia. Comprehensive studies involving sedimentology, paleontology, and Sr isotopes have offered valuable insights into the sedimentary characteristics and depositional environments of these basins during the Neogene period. In the west, the Kasaba Basin features an early to middle Miocene carbonate-clastic succession that developed on the Late Cretaceous Beydağları autochthon, overlain by Paleocene-Eocene neritic carbonates. In contrast, the Aksu-Gebiz Basin in the east presents a transgressive sequence of middle Miocene to Pliocene clastics and carbonates, which developed on different basement units, including the Mesozoic metamorphosed carbonates and the Antalya Complex in the west. Biostratigraphic studies in the Kasaba (Kaş) region revealed 9 genera and 23 species of planktonic foraminifera in the Kasaba Formation, and 12 genera and 29 species in the Sinekçi Fm., marking the lower boundary of the <em>Orbulina suturalis</em> Lineage Subzone (MMi5a) of the middle Miocene. Similarly, in the Gebiz (Aksu) region, the planktonic foraminifera indicate the lower boundary of the MMi12a <em>Globigerinoides obliquus extremus</em>-<em>Globorotalia suterae</em> Interval Subzone of the late Miocene. Benthic foraminifera indicative of shelf environments were identified in both regions. Whole-rock strontium isotope chemostratigraphy revealed ages ranging from 14.3 to 23.7 Ma based on ⁸⁷Sr/⁸⁶Sr ratios from three key samples. Overall, studies in the Kasaba Basin suggest a lower to middle Miocene age with shallow marine environments, consistent with Serravallian to Langhian periods. In the Aksu-Gebiz Basin, detailed investigations of the Karpuzçay Formation identified a mid-Tortonian age. This age, combined with sedimentological and structural data, provides insights into the basin's tectonic evolution and flexural effects. Planktonic and benthic foraminifera within the sequence reflect inner shelf environments throughout. The strontium isotope analysis of samples from the Aksu-Gebiz Basin revealed significant variations in ⁸⁷Sr/⁸⁶Sr ratios, with ages ranging from the Tortonian (9.0 Ma) to the Messinian (5.3 Ma). By integrating biostratigraphy and whole-rock Sr isotope stratigraphy, this study refines the Neogene chronological framework of the Kasaba and Aksu-Gebiz Basins, providing new insights into the Eastern Mediterranean's geological history. These findings also improve stratigraphic correlations with adjacent basins, offering a more comprehensive regional context.</div></div>","PeriodicalId":14874,"journal":{"name":"Journal of African Earth Sciences","volume":"229 ","pages":"Article 105674"},"PeriodicalIF":2.2,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924536","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}