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22 pages, 6163 KB  
Article
Provenance and Evolution of Heavy Minerals in Feldspar-Rich Sands from Wadi El Tuleia: A Mineralogical and Geochemical Approach
by Taher M. Shahin, Hatem M. El-Desoky, Sherif A. Taalab, Osama R. Elshahat, Assem M. El-Bery, Antoaneta Ene and Hamdy A. Awad
Minerals 2025, 15(10), 1058; https://doi.org/10.3390/min15101058 - 5 Oct 2025
Viewed by 197
Abstract
The heavy mineral-rich wadi deposits sourced from various wadis close to Gabal Homret Waggat in the central eastern Desert of Egypt are being analyzed to assess their genesis and paleoenvironment. This study integrates remote sensing (ALOS/PALSAR DEM and ASTER imagery), mineralogical, and geochemical [...] Read more.
The heavy mineral-rich wadi deposits sourced from various wadis close to Gabal Homret Waggat in the central eastern Desert of Egypt are being analyzed to assess their genesis and paleoenvironment. This study integrates remote sensing (ALOS/PALSAR DEM and ASTER imagery), mineralogical, and geochemical analyses (XRF and SEM-EDX). Remote sensing analysis (ASTER and ALOS/PALSAR) delineated three main watersheds and identified granitic plutons as the primary source rocks. Mineralogical analysis revealed a diverse heavy mineral assemblage, including zircon, rutile, ilmenite, magnetite, staurolite, and sillimanite, indicative of a provenance dominated by granitic and metamorphic rocks. Grain size analysis shows that the samples range from very platykurtic to extremely leptokurtic (Kg: 0.598–5.350 φ), indicating deposition in predominantly fluvial environments. Geochemical data show enrichment in SiO2, Al2O3, K2O, and Na2O, indicating a felsic (granitic) source with low Chemical Index of Alteration (CIA: 41.89–51.83) and Plagioclase Index of Alteration (PIA: 37.97–52.78) values, and indicating that the source rocks show low to moderate chemical weathering. Tectonic discrimination diagrams suggest that the source rocks were formed in a continental island arc or active continental margin, consistent with the Arabian–Nubian Shield. The presence of economically valuable minerals like zircon and rare-earth-element-bearing monazite and columbite highlights the significant resource potential of these placer deposits. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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18 pages, 19543 KB  
Article
Detrital Zircon U-Pb Age Data and Geochemistry of Clastic Rocks in the Xiahe–Hezuo Area: Implications for the Late Paleozoic–Mesozoic Tectonic Evolution of the West Qinling Orogen
by Hang Li, Kang Yan, Kangning Li, Ke Yang, Baocheng Fan, Zhongkai Xue, Li Chen and Haomin Guo
Geosciences 2025, 15(10), 384; https://doi.org/10.3390/geosciences15100384 - 3 Oct 2025
Viewed by 195
Abstract
The West Qinling Orogenic Belt (WQOB) contains a sedimentary succession that is approximately 15 km thick, spanning from the Carboniferous to the Jurassic period. This succession offers critical insights into the tectonic evolution of the Paleo-Tethys Ocean. While previous models have suggested various [...] Read more.
The West Qinling Orogenic Belt (WQOB) contains a sedimentary succession that is approximately 15 km thick, spanning from the Carboniferous to the Jurassic period. This succession offers critical insights into the tectonic evolution of the Paleo-Tethys Ocean. While previous models have suggested various depositional environments, the late Paleozoic to Mesozoic tectonic evolution of the WQOB is still not fully understood. In this study, we incorporate new detrital zircon U-Pb age data and whole-rock geochemical analyses from six stratigraphic units, dating back to the Carboniferous to Triassic periods in the Xiahe–Hezuo region, alongside existing datasets. The detrital zircon age spectra from the WQOB reveal three distinct groups: Devonian–Carboniferous strata exhibit dominant Neoproterozoic (~800–900 Ma) zircon populations, whereas Permian–Triassic rock samples show prominent Paleoproterozoic (1840–1880 Ma) and Archean (2450–2500 Ma) peaks. A minor Neoproterozoic component in Permian spectra disappears by the Triassic, while Jurassic–Cretaceous assemblages lack Precambrian grains. These trends reflect evolving source terranes linked to Paleo-Tethyan subduction dynamics. Furthermore, the geochemical signatures of the Devonian–Triassic clastic rocks align with the composition of upper continental crust, indicating a tectonic relationship with continental island arcs and active continental margins. By synthesizing these findings with established detrital zircon ages, magmatic records, and geophysical data, we propose that the WQOB underwent pre-Triassic tectonic evolution that was marked by pre-Triassic subduction and localized extension during the process of continental underthrusting. Full article
(This article belongs to the Special Issue Detrital Minerals Geochronology and Sedimentary Provenance)
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23 pages, 13715 KB  
Article
Sedimentary Environment, Tectonic Setting, and Paleogeographic Reconstruction of the Late Jurassic Weimei Formation in Dingri, Southern Tibet
by Jie Wang, Songtao Yan, Hao Huang, Tao Liu, Chongyang Xin and Song Chen
Minerals 2025, 15(10), 1040; https://doi.org/10.3390/min15101040 - 30 Sep 2025
Viewed by 263
Abstract
The Weimei Formation, the most complete Upper Jurassic sedimentary sequence in the Tethyan Himalaya, is crucial for understanding the tectono-sedimentary evolution of the northern Indian margin. However, its depositional environment remains debated, with conflicting shallow- and deep-water interpretations. This study integrates sedimentary facies, [...] Read more.
The Weimei Formation, the most complete Upper Jurassic sedimentary sequence in the Tethyan Himalaya, is crucial for understanding the tectono-sedimentary evolution of the northern Indian margin. However, its depositional environment remains debated, with conflicting shallow- and deep-water interpretations. This study integrates sedimentary facies, petrography, zircon geochronology, and geochemical analyses to constrain the provenance, depositional environment, and tectonic setting of the Weimei Formation. The results reveal that the sedimentary system primarily consists of shoreface, delta, and shelf facies, with locally developed slope-incised valleys. Detrital zircon ages are concentrated at ~468 Ma and ~964 Ma, indicating a provenance mainly derived from the Indian continent. Geochemical characteristics, such as high SiO2, low Na2O–CaO–TiO2 contents, right-leaning REE patterns, and significant negative Eu anomalies, suggest the derivation of sediments from felsic upper crustal recycling within a passive continental margin. Stratigraphic comparison between southern and northern Tethyan Himalayan sub-zones reveals a paleogeographic “uplift–depression” pattern, characterized by the coexistence of shoreface–shelf deposits and slope-incised valleys. This study provides key evidence for reconstructing the Late Jurassic paleogeography of the northern Indian margin and the tectonic evolution of the Neo-Tethys Ocean. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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16 pages, 9887 KB  
Article
Differences in Mesozoic–Cenozoic Structural Deformation Between the Northern and Southern Parts of the East China Sea Shelf Basin and Their Dynamic Mechanisms
by Chuansheng Yang, Junlan Song, Yanqiu Yang, Luning Shang, Jing Liao and Yamei Zhou
J. Mar. Sci. Eng. 2025, 13(9), 1809; https://doi.org/10.3390/jmse13091809 - 18 Sep 2025
Viewed by 335
Abstract
The East China Sea Shelf Basin (ECSSB) and its adjacent areas, as key regions of the ocean–continent transition zone, have been affected by multiple complex plate collisions, subduction, and back-arc tension since the Mesozoic Era. The structural deformation provides a large amount of [...] Read more.
The East China Sea Shelf Basin (ECSSB) and its adjacent areas, as key regions of the ocean–continent transition zone, have been affected by multiple complex plate collisions, subduction, and back-arc tension since the Mesozoic Era. The structural deformation provides a large amount of geological information on the ocean–continent transition zone. There are significant spatiotemporal differences in the structural deformation within the basin. However, the research remains insufficient and understanding is inconsistent, especially regarding the systematic study of the differences and dynamic mechanisms of north–south structural deformation, which is relatively lacking. This study is based on two-dimensional multi-channel deep reflection seismic profiles spanning the southern and northern basin. Through an integrated re-analysis of gravity, magnetic, and OBS data, the deformation characteristics and processes of the Meso-Cenozoic structures in the basin are analyzed. The differences in structural deformation between the southern and northern basin are summarized, and the controlling effects of deep crust–mantle activity and the influencing factors of shallow structural deformation are explored. Based on deep reflection seismic profiles, the structural deformation characteristics of the Yushan–Kume fault are revealed for the first time, and it is proposed that NW faults, represented by the Yushan–Kume fault, have important tuning effects on the north–south structural differential deformation in the ECSSB. The thermal subsidence of the lithosphere is the direct cause of the development of the Mesozoic ECSSB, while the subduction of the Paleo-Pacific plate is one of the important factors contributing to it. The combined effect of the two has led to significant differences between the northern and southern Mesozoic basin. During the Cenozoic Era, the alternating subduction and changes in the direction of subduction of the Pacific Plate led to spatiotemporal differences in structural deformation within the ECSSB. The development of NW faults was a key factor in the differences in structural deformation between the northern and southern basin. The study of structural deformation differences in the ECSSB not only deepens our understanding of the tectonic evolution in the East Asian continental margin region, but also has important significance for the exploration and evaluation of deep hydrocarbon resources in the ECSSB. Full article
(This article belongs to the Section Geological Oceanography)
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19 pages, 10464 KB  
Article
Callovian-Oxfordian Ironstones at the Northwestern Margin of the Neo-Tethys Ocean, with Mineralogically Diverse Iron Ooids: Example from Kutch Basin, India
by Arpita Chakraborty, Santanu Banerjee, Suraj Arjun Bhosale and Sabyasachi Mandal
Minerals 2025, 15(9), 990; https://doi.org/10.3390/min15090990 - 18 Sep 2025
Viewed by 400
Abstract
Multiple ironstone beds formed during the Callovian-Oxfordian times as a consequence of intense continental weathering, upwelling, and hydrothermal activity. This study examines the compositional differences between core and rim, and the origin of iron ooids along the northwestern margin of the Neo-Tethys Ocean [...] Read more.
Multiple ironstone beds formed during the Callovian-Oxfordian times as a consequence of intense continental weathering, upwelling, and hydrothermal activity. This study examines the compositional differences between core and rim, and the origin of iron ooids along the northwestern margin of the Neo-Tethys Ocean to highlight sea-level fluctuations, redox conditions, and elemental influx. An integrated sedimentological study, including petrography, mineralogy, micro-texture, and mineral chemistry, was carried out to explain the origin and implications of ironstones. The ~14 m thick Callovian-Oxfordian, marginal marine deposits in the Kutch Basin, in western India, exhibit iron ooids, predominantly formed in oolitic shoals during transgression, associated with lagoonal siliciclastics. Callovian shoals interbedded with lagoonal facies record minor sea-level fluctuations, whereas the Oxfordian deposit records a major transgression and condensation, resulting in extensive ironstone deposits. The ooid cortices and nuclei exhibit distinctive mineralogy and micro-textures: glauconitic smectite exhibits poorly-developed rosettes, chamosite displays flower-like, and goethite shows rod-like features. Three types of ooids are formed: (i) monomineralic ooids are entirely of chamosite or goethite, (ii) quartz-nucleated ooids, and (iii) composite ooids with either chamosite core and goethite rim, or chamosite core and glauconitic smectite rim. The assemblages within iron ooids reflect variation in depositional redox conditions: glauconitic smectite develops under suboxic lagoonal flank, chamosite forms in anoxic central lagoon, and goethite precipitates on oxic shoals. Full article
(This article belongs to the Special Issue Tectonic Setting and Provenance of Sedimentary Rocks)
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19 pages, 4516 KB  
Article
Accurate Extraction Method for Continental Margin FOS Line Considering Terrain Continuity
by Dong Wang, Jian Dong, Zhiqiang Zhang, Tian Xie, Xiaodong Ma and Tianyue Wang
J. Mar. Sci. Eng. 2025, 13(9), 1744; https://doi.org/10.3390/jmse13091744 - 10 Sep 2025
Viewed by 283
Abstract
This paper addresses the limitations and low efficiency of current methods for precise identification of continental margin break points in the delimitation of the outer continental shelf. From a three-dimensional perspective, it proposes a novel method for extracting the foot-of-slope (FOS) line of [...] Read more.
This paper addresses the limitations and low efficiency of current methods for precise identification of continental margin break points in the delimitation of the outer continental shelf. From a three-dimensional perspective, it proposes a novel method for extracting the foot-of-slope (FOS) line of the continental margin that considers terrain continuity. First, the algorithm uses the rolling ball transform to classify the strength of the attributes of negative topographic feature lines of the seafloor. Then, it conducts experiments on two sets of negative topographic feature lines with strong and weak attributes. By calculating the proportion of the intersection of weak attribute lines with strong ones, it establishes a hierarchical pattern of importance for these lines. Subsequently, the algorithm integrates a multi-factor screening process for the continental margin FOS line. Finally, it achieves accurate and efficient extraction of the FOS line while preserving terrain continuity. The method’s effectiveness is verified through visual interpretation, comparison, and efficiency experiments in a real digital depth model. The results indicate that the algorithm can accurately extract the FOS line, effectively distinguish the continental margin, and maintain high efficiency. Full article
(This article belongs to the Special Issue Data-Driven Methods for Marine Structures, Second Edition)
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5 pages, 168 KB  
Editorial
Advances in Marine Gas Hydrate Exploration and Discovery
by Wei Zhang, Pibo Su, Jiliang Wang and Qianyong Liang
J. Mar. Sci. Eng. 2025, 13(9), 1689; https://doi.org/10.3390/jmse13091689 - 2 Sep 2025
Viewed by 503
Abstract
Natural gas hydrates are extensively distributed across terrestrial permafrost zones and continental margins worldwide [...] Full article
(This article belongs to the Special Issue Advances in Marine Gas Hydrate Exploration and Discovery)
22 pages, 10856 KB  
Article
Provenance Analysis of the Silurian Kepingtag Formation in the Northwest Margin of Tarim Basin-Evidence from Petrology and Geochemistry
by Qiyuan Zhang, Jingchun Tian, Xiang Zhang, Shuyao Hao, Zhenping Li and Kang Ji
Minerals 2025, 15(9), 934; https://doi.org/10.3390/min15090934 - 1 Sep 2025
Viewed by 462
Abstract
The integration of petrological and geochemical analyses serves as an effective methodology for reconstructing depositional environments and constraining sediment provenance within distinct tectonic frameworks. This study investigates the provenance characteristics of the Silurian Kepingtag Formation in the northwestern Tarim Basin through an integrated [...] Read more.
The integration of petrological and geochemical analyses serves as an effective methodology for reconstructing depositional environments and constraining sediment provenance within distinct tectonic frameworks. This study investigates the provenance characteristics of the Silurian Kepingtag Formation in the northwestern Tarim Basin through an integrated approach combining field outcrop observations and laboratory analyses. Fieldwork covers the Sishichang, Dawangou, and Tongguzibulong sections, while laboratory analyses include clastic component identification, whole-rock major and trace element geochemical analysis, and rare earth element (REE) profiling. These efforts enable a systematic evaluation of sediment sources and their tectonic linkages. The research provides a theoretical basis for understanding the tectono-sedimentary framework of the northwestern Tarim Basin during the Early Silurian and offers significant guidance for reconstructing the lithofacies paleogeographic pattern of the basin during this period. Petrographic analyses reveal a lithological assemblage dominated by lithic quartz sandstones and lithic sandstones, with subordinate feldspathic lithic sandstones. Quartz exhibits secondary overgrowths. In a relatively stable tectonic environment, sediments undergo a gentle burial rate, which favors the formation of this phenomenon. Lithic fragments are dominated by magmatic lithics, indicating that the source contains magmatic rocks. Detrital component analysis reveals that the provenance of Kepingtag Formation sandstones in the study area is predominantly characterized by stable craton and recycled orogenic belt tectonic settings. Integrated geochemical datasets from major element compositions and trace element signatures constrain the provenance characteristics of the Kepingtag Formation sandstones. Major element ratios demonstrate predominant contributions from felsic igneous source rocks, while trace element ratios are diagnostic of sediment derivation from passive continental margin settings, consistent with prolonged tectonic quiescence along the northern Tarim cratonic margin during Silurian deposition The CIA index indicates that the Silurian Kepingtag Formation in the study area exhibits weak to moderate weathering. Integrating the above analyses, the Tabei Uplift—ancient craton setting—is interpreted as the likely provenance source for the sandstones of the Kepingtag Formation in the northwestern Tarim Basin. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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14 pages, 13739 KB  
Article
Reconstruction of the Cretaceous Palaeogeographic Position of Hainan Island and Its Tectonic Significance
by Mingming Wang, Yang Zhou, Yongjian Yao, Weijie Zhang, Huaiyang Zhou and Qingsong Liu
J. Mar. Sci. Eng. 2025, 13(9), 1681; https://doi.org/10.3390/jmse13091681 - 1 Sep 2025
Viewed by 582
Abstract
Reconstruction of the palaeogeographical location of Hainan Island is important for understanding the interaction between Indochina and South China. In this study, we integrate topographic relief, gravity anomalies, and magnetic anomalies, along with geological constraints, to determine the Cretaceous location of Hainan Island. [...] Read more.
Reconstruction of the palaeogeographical location of Hainan Island is important for understanding the interaction between Indochina and South China. In this study, we integrate topographic relief, gravity anomalies, and magnetic anomalies, along with geological constraints, to determine the Cretaceous location of Hainan Island. The results show that Hainan Island was connected with South China in the Cretaceous and located in the Beibu Gulf Basin, and then rifted from South China with about 230 km displacement along the southeast direction during the Cenozoic. Further geological evidence suggests that Hainan Island and South China have co-evolved since at least the Permian. Hainan Island was rifted from South China from the Palaeocene to the Oligocene due to escape tectonics caused by the India–Asia collision. These new findings provide important clues for investigating the impact of the India–Asia collision and the continental margin evolution of South China. Full article
(This article belongs to the Section Geological Oceanography)
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24 pages, 9686 KB  
Article
The Petrogenesis of Early Permian Granodiorites in the Northern Segment of the Changning-Menglian Suture Zone, Western Yunnan, and Their Tectonic Implications
by Jiajia Liu, Zhen Jia, Jiyuan Wang, Feng Zhao, Junbao Luo, Feiyang Xu and Fuchuan Chen
Minerals 2025, 15(9), 894; https://doi.org/10.3390/min15090894 - 23 Aug 2025
Viewed by 682
Abstract
The Changning-Menglian suture zone, as the remnant of the main Paleo-Tethyan oceanic basin in its southern segment, lacks direct magmatic evidence constraining the timing of subduction initiation in its northern segment. The petrogenesis and tectonic setting of the newly discovered Early Permian (~280 [...] Read more.
The Changning-Menglian suture zone, as the remnant of the main Paleo-Tethyan oceanic basin in its southern segment, lacks direct magmatic evidence constraining the timing of subduction initiation in its northern segment. The petrogenesis and tectonic setting of the newly discovered Early Permian (~280 Ma) Wayao granodiorite in the northern segment remain unclear, hindering our understanding of the timing of subduction initiation and processes of the Paleo-Tethyan Ocean in the Changning-Menglian suture zone. This study presents systematic petrographic, zircon U-Pb geochronological, whole-rock major and trace element geochemical, and Sr-Nd-Hf isotopic analyses on the newly discovered Early Permian granodiorite in the Wayao area, northern segment of the Changning-Menglian suture zone, western Yunnan. Zircon U-Pb dating yields a crystallization age of ca. 280 Ma, confirming its emplacement during the Early Permian. The petrogeochemical characteristics indicate that it belongs to the metaluminous, calc-alkaline series of I-type granite. It is enriched in large-ion lithophile elements (LILEs; e.g., Rb, Th, U, La, Pb) and depleted in high-field-strength elements (HFSEs; e.g., Ba, Nb, Sr, Ti), exhibiting a pronounced negative Eu anomaly. Whole-rock Sr-Nd isotopes (εNd(t) = −5.6–−6.1) and zircon Hf isotopes (εHf(t) = −1.34–−10.01) suggest that the magma was predominantly derived from the partial melting of ancient crustal material (primarily metamorphosed basic rocks, such as amphibolite), with a minor addition of mantle-derived components (magma mixing). Combined with petrogeochemical discriminant diagrams (e.g., Sr/Y vs. Y, Rb vs. Yb + Ta) and the regional geological context, this granodiorite is interpreted to have formed in an active continental margin tectonic setting associated with the eastward subduction of the Paleo-Tethys Ocean (represented by the Changning-Menglian Ocean). This discovery fills the gap in the record of Early Permian subduction-related magmatic rocks in the northern segment of the Changning-Menglian suture zone. It provides crucial petrological evidence constraining that the eastward subduction and consumption of the northern Paleo-Tethys Ocean had already commenced by the Early Permian. Full article
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17 pages, 3187 KB  
Article
Tectonic Uplift and Hydrocarbon Generation Constraints from Low-Temperature Thermochronology in the Yindongzi Area, Ordos Basin
by Guangyuan Xing, Zhanli Ren, Kai Qi, Liyong Fan, Junping Cui, Jinbu Li, Zhuo Han and Sasa Guo
Minerals 2025, 15(9), 893; https://doi.org/10.3390/min15090893 - 22 Aug 2025
Viewed by 635
Abstract
This study investigates the uplift and exhumation history of the southern segment of the western margin of the Ordos Basin using low-temperature thermochronology, including zircon (U-Th)/He (ZHe), apatite fission-track (AFT), and apatite (U-Th)/He (AHe) data, combined with thermal history modeling. The study area [...] Read more.
This study investigates the uplift and exhumation history of the southern segment of the western margin of the Ordos Basin using low-temperature thermochronology, including zircon (U-Th)/He (ZHe), apatite fission-track (AFT), and apatite (U-Th)/He (AHe) data, combined with thermal history modeling. The study area exhibits a complex structural framework shaped by multiple deformation events, leading to the formation of extensively developed fault systems. Such faulting can adversely affect hydrocarbon preservation. To better constrain the timing of fault reactivation in this area, we carried out an integrated study involving low-temperature thermochronology and burial history modeling. The results reveal a complex, multi-phase thermal-tectonic evolution since the Late Paleozoic. The ZHe ages (291–410 Ma) indicate deep burial and heating related to Late Devonian–Early Permian tectonism and basin sedimentation, reflecting early orogenic activity along the western North China Craton. During the Late Jurassic to Early Cretaceous (165–120 Ma), the study area experienced widespread and differential uplift and cooling, controlled by the Yanshanian Orogeny. Samples on the western side of the fault show earlier and more rapid cooling than those on the eastern side, suggesting a fault-controlled, basinward-propagating exhumation pattern. The cooling period indicated by AHe data and thermal models reflects the Cenozoic uplift, likely induced by far-field compression from the rising northeastern Tibetan Plateau. These findings emphasize the critical role of inherited faults not only as thermal-tectonic boundaries during the Mesozoic but also as a pathway for hydrocarbon migration. Meanwhile, thermal history models based on borehole data further reveal that the study area underwent prolonged burial and heating during the Mesozoic, reaching peak temperatures for hydrocarbon generation in the Late Jurassic. The timing of major cooling events corresponds to the main stages of hydrocarbon expulsion and migration. In particular, the differential uplift since the Mesozoic created structural traps and migration pathways that likely facilitated hydrocarbon accumulation along the western fault zones. The spatial and temporal differences among the samples underscore the structural segmentation and dynamic response of the continental interior to both regional and far-field tectonic forces, while also providing crucial constraints on the petroleum system evolution in this tectonically complex region. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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24 pages, 14790 KB  
Article
Morphodynamics, Genesis, and Anthropogenically Modulated Evolution of the Elfeija Continental Dune Field, Arid Southeastern Morocco
by Rachid Amiha, Belkacem Kabbachi, Mohamed Ait Haddou, Adolfo Quesada-Román, Youssef Bouchriti and Mohamed Abioui
Earth 2025, 6(3), 100; https://doi.org/10.3390/earth6030100 - 19 Aug 2025
Cited by 1 | Viewed by 559
Abstract
The Elfeija Dune Field (EDF) is a continental aeolian system in an arid region of southeastern Morocco. Studying this system is critical for understanding the effects of mounting climatic and anthropogenic pressures. This study provides a comprehensive characterization of the EDF’s morphology, sedimentology, [...] Read more.
The Elfeija Dune Field (EDF) is a continental aeolian system in an arid region of southeastern Morocco. Studying this system is critical for understanding the effects of mounting climatic and anthropogenic pressures. This study provides a comprehensive characterization of the EDF’s morphology, sedimentology, aeolian dynamics, genesis, and recent evolution. A multi-scale, multidisciplinary approach was adopted, integrating field observations, sedimentological analyses, MERRA-2 reanalysis wind data, cartographic analysis, digital terrain modeling, and morphometric measurements. The results reveal an active 30 km2 dune field, elongated WSW-ENE, which is divisible into three morphodynamic zones with a high dune density (80–90 dunes/km2). The wind regime is predominantly from the W to WSW, driving a net ENE sand transport and creating conditions conducive to barchan formation (RDP/DP > 0.78). Sediments are quartz dominated, with significant calcite and various clay minerals (illite, kaolinite, and smectite). Dune sands are primarily fine- to medium-grained and well sorted, in contrast to the more poorly sorted interdune deposits. The landscape is dominated by barchans (mean height H = 2.5 m; mean length L = 50 m) and their coalescent forms, indicating sustained aeolian activity. The potential sand flux was estimated at 1.7 kg/m/s, with a dune collision probability of 32%. The field’s genesis is hypothesized to be controlled by a topographically induced Venturi effect, with an initiation approximately 1000 years ago, potentially linked to the Medieval Climatic Optimum. Significant anthropogenic impacts from expanding irrigated agriculture are observed at the dune field margins. By providing a detailed characterization of the EDF and its sensitivity to natural and anthropogenic forcings, this study establishes a critical baseline for the sustainable management of arid environments. Full article
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19 pages, 4015 KB  
Article
New Geochemical Insights into Pre-Khorat Paleoenvironments: A Case Study of Triassic–Jurassic Reddish Sedimentary Rocks in Thailand
by Vimoltip Singtuen, Burapha Phajuy and Punya Charusiri
Geosciences 2025, 15(8), 324; https://doi.org/10.3390/geosciences15080324 - 19 Aug 2025
Viewed by 755
Abstract
The Nam Phong Formation, a key unit of the pre-Khorat Group in the western Khorat Plateau, provides critical insights into the Mesozoic geological evolution of northeastern Thailand. This study presents the first integrated petrographic and geochemical investigation of the formation within Khon Kaen [...] Read more.
The Nam Phong Formation, a key unit of the pre-Khorat Group in the western Khorat Plateau, provides critical insights into the Mesozoic geological evolution of northeastern Thailand. This study presents the first integrated petrographic and geochemical investigation of the formation within Khon Kaen Geopark to reconstruct its Late Triassic–Early Jurassic depositional settings, provenance, and paleoclimate. A detailed stratigraphic section and five supplementary sites reveal litharenite and lithic wacke sandstones, interbedded with red paleosols and polymictic conglomerates. Sedimentary structures—such as trough and planar cross-bedding, erosional surfaces, and mature paleosols—indicate deposition in a high-energy braided fluvial system under semi-arid to subhumid conditions with episodic subaerial exposure. Petrographic analysis identifies abundant quartz, feldspar, and volcanic lithic fragments. Geochemical data and REE patterns, including diagnostic negative Ce anomalies, provide compelling evidence for provenance from active continental margins and oxidizing weathering conditions. These findings point to a tectonically active syn-rift basin influenced by climatic variability. Strikingly, the Nam Phong Formation exhibits paleoenvironmental and sedimentological features comparable to the modern Ebro Basin in northeastern Spain, highlighting the relevance of uniformitarian principles in interpreting ancient continental depositional systems. Full article
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30 pages, 5374 KB  
Article
Provenance and Tectonic Controls in Eastern Junggar: Insights from Petrography and REE Geochemistry
by Shengzhu Wang, Hongzhou Yu, Baosheng Li, Jinqi Han, Can Zhao, Yaoyun Guo, Jiaye Liu, Chang Su, Xu Chang, Tong Wu and Haoqing Huang
Molecules 2025, 30(16), 3399; https://doi.org/10.3390/molecules30163399 - 18 Aug 2025
Cited by 1 | Viewed by 765
Abstract
Rare earth elements (REEs) and trace elements, due to their relative stability during sedimentary processes, are effective geochemical proxies for sediment provenance. In the Dongdaohaizi Depression of the eastern Junggar Basin, the provenance of the Middle Jurassic Sangonghe Formation remains contentious. In this [...] Read more.
Rare earth elements (REEs) and trace elements, due to their relative stability during sedimentary processes, are effective geochemical proxies for sediment provenance. In the Dongdaohaizi Depression of the eastern Junggar Basin, the provenance of the Middle Jurassic Sangonghe Formation remains contentious. In this study, representative sandstone samples were systematically collected from all three members of the Sangonghe Formation in both the Dongdaohaizi Depression and its western margin. Through comprehensive petrographic and geochemical analyses, we obtained the following results. The Sangonghe Formation is primarily composed of feldspathic lithic sandstones, lithic sandstones, and minor lithic–feldspathic sandstones. The heavy mineral assemblage includes zircon, garnet, chromite, and rutile, suggesting source rocks of intermediate to acidic igneous, metamorphic, and mafic lithologies. The total REE contents range from 101.84 to 192.68 μg/g, with an average of 161.80 μg/g. The ∑LREE/∑HREE ratios vary from 6.59 to 13.25 (average 10.96), and the average δEu values are close to 1. The δCe value ranges from 1.09 to 1.13 (average 1.11). Trace element discrimination diagrams, including La-Th-Sc, Th-Co-Zr/10, Th-Sc-Zr/10, and La/Y-Sc/Cr ternary plots, indicate that most samples fall within the continental island arc domain, with a few plotting in the passive continental margin field. Comparison with potential surrounding source regions reveals dual provenances: an eastern source from the Kalamaili Mountains and a western source from the Zhayier Mountains. During the Early Jurassic, these two orogenic belts acted as distinct sediment sources. The Zhayier Mountains provided stronger input, with fluvial and tidal processes transporting sediments into the basin, establishing the primary subsidence center in the west of the depression. By the Middle Jurassic, continued thrusting of surrounding fold belts caused a migration of the lake center and the main depocenter to the western edge of the Dongdaohaizi Depression, while the former depocenter gradually diminished. Furthermore, sustained erosion and denudation of the Mosowan Uplift during the Early–Middle Jurassic reduced its function as a structural barrier, thereby promoting increased mixing between eastern and western sediment sources. The study not only refines existing paleogeographic models of the Junggar Basin, but also demonstrates the utility of REE–trace geochemistry in deciphering complex provenance systems in tectonically active basins. Full article
(This article belongs to the Special Issue Innovative Chemical Technologies for Rare Earth Element Processing)
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Article
Three-Dimensional Morphometric Analysis of the Columbretes Grande Turbidite Channel (Ebro Continental Margin, NW Mediterranean)
by José Luis Casamor
Geosciences 2025, 15(8), 318; https://doi.org/10.3390/geosciences15080318 - 15 Aug 2025
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Abstract
Turbidite channels are final conduits for the transfer of terrigenous detritus to the deep-sea depositional systems. Studying their morphology and geometric parameters can provide information on density flow characteristics and sedimentary processes, making it an objective and quantitative way to differentiate the deep-sea [...] Read more.
Turbidite channels are final conduits for the transfer of terrigenous detritus to the deep-sea depositional systems. Studying their morphology and geometric parameters can provide information on density flow characteristics and sedimentary processes, making it an objective and quantitative way to differentiate the deep-sea deposits they feed, which are of special interest to the oil industry. In this work, the morphology is studied, the main geometric parameters are calculated, and the potential sedimentary fill of a turbiditic channel, the Columbretes Grande channel, located on the Ebro continental margin (NW Mediterranean Sea), is reconstructed and visualized in 3D. This complete morphometric analysis shows a concave and smooth channel indicating a profile in equilibrium with local evidence of erosion. Considering the height of the flanks (< 150 m), the existence of well-developed levees, the high sinuosity of some of its reaches, and the relatively low slopes, the channel can be classified as depositional. The sinuosity index is close to 2 in some courses, and the gentle slopes suggest that the fine-grained turbidity currents that episodically circulate in its interior reach the channel’s end. Full article
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