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16 pages, 2031 KB  
Article
Applying Target Capture Sequencing to Unravel the Anthurium Section Pachyneurium (Araceae), with Emphasis on Brazilian Species
by Mel C. Camelo, Georgios J. Pappas, Micheline C. Silva, Lívia G. Temponi, Marcus A. N. Coelho, José F. A. Baumgratz and Mónica M. Carlsen
Plants 2026, 15(6), 866; https://doi.org/10.3390/plants15060866 - 11 Mar 2026
Viewed by 431
Abstract
Anthurium (Araceae) is one of the most species-rich Neotropical genera, yet its infrageneric classification remains unresolved. This study tests the monophyly of the morphologically defined Anthurium sect. Pachyneurium diagnosed by rosulate habit, involute prefoliation, and absence of a collective vein with a focus [...] Read more.
Anthurium (Araceae) is one of the most species-rich Neotropical genera, yet its infrageneric classification remains unresolved. This study tests the monophyly of the morphologically defined Anthurium sect. Pachyneurium diagnosed by rosulate habit, involute prefoliation, and absence of a collective vein with a focus on Brazilian species. Using target capture sequencing (Angiosperms353 probe set), we generated a phylogenomic dataset for 35 Anthurium species (18 from sect. Pachyneurium) and conducted maximum likelihood and coalescent-based analyses. Our results demonstrate that sect. Pachyneurium is not monophyletic as traditionally circumscribed. Brazilian species previously assigned to the section are recovered in three geographically structured and strongly supported lineages: Amazonian, Atlantic Forest, and Caatinga/Cerrado. The Atlantic Forest lineage is unexpectedly resolved as sister to A. coriaceum (sect. Urospadix), revealing an evolutionary relationship not predicted by morphology. Divergence-time estimates place the origin of crown Anthurium in the Paleocene (~62 Ma), with diversification of the Brazilian lineages occurring during the Miocene (20–3 Ma), coinciding with major geoclimatic events in South America. Our findings indicate that key diagnostic morphological characters are homoplastic and provide a phylogenomic framework for revising the infrageneric classification of Anthurium. By identifying evolutionarily distinct lineages, this study also contributes to prioritizing conservation efforts in threatened Neotropical biomes. Full article
(This article belongs to the Special Issue Recent Advancements in Taxonomy and Phylogeny of Plants)
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26 pages, 5586 KB  
Article
Paleoclimate and Depositional Controls on Organic Carbon Storage and Sustainable Unconventional Resource Potential of Late Cretaceous–Paleocene Black Shales, Dakhla Basin, Egypt
by Samar R. Soliman, Yasser F. Salama, Ibrahim M. Abd-ElGaied, Mohamed I. El-Sayed, Gebely A. Abu El-Kheir and Zakaria M. Abd-allah
Sustainability 2026, 18(5), 2332; https://doi.org/10.3390/su18052332 - 28 Feb 2026
Viewed by 280
Abstract
The Dakhla Formation in the Western Desert of Egypt comprises a thick Cretaceous–Paleocene, ranging from light gray to dark gray, that represents an underexplored geological resource relevant to sustainable energy and environmental conditions. The present study integrates mineralogical and geochemical data based on [...] Read more.
The Dakhla Formation in the Western Desert of Egypt comprises a thick Cretaceous–Paleocene, ranging from light gray to dark gray, that represents an underexplored geological resource relevant to sustainable energy and environmental conditions. The present study integrates mineralogical and geochemical data based on samples collected from outcrop at Mut-Manflout and subsurface core samples from Abu Tartur (62–150 m depth) to evaluate depositional environments, paleoclimate, chemical weathering, and organic carbon accumulation. Major and trace element geochemistry, clay mineralogy, total organic carbon (TOC), Rock-Eval pyrolysis, and calorific values are used to assess hydrocarbon potential while minimizing exploration uncertainty. Mineralogical analyses indicate that smectite and kaolinite dominate the Mut-Manflout shales; in contrast, significant relationships among primary oxides and trace elements indicate a source from detrital materials, and elevated Chemical Alteration Index (CIA) values are indicative of intense chemical weathering under humid paleoclimatic conditions. The geochemical results show that Abu Tartur shale core samples contain higher TOC values (0.73–2.08 wt%) and oil-prone kerogen (types I–II to II–III), while Mut-Manflout outcrop samples exhibit lower TOC contents (0.23–1.15 wt%) and gas-prone kerogen (types III–IV). Both successions are thermally immature, with a strong relationship between TOC and S1 values indicating the presence of indigenous hydrocarbons. By comparing surface and subsurface shales, the present study highlights the importance of site-specific characterization in reducing environmental and economic risks associated with unconventional resource exploration. The results support sustainable resource planning by improving understanding of organic carbon storage, paleoclimate controls, and the responsible evaluation of black shale systems in arid regions such as the Western Desert of Egypt. Full article
(This article belongs to the Section Air, Climate Change and Sustainability)
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16 pages, 5310 KB  
Article
Mitochondrial Phylogenomics of Tenthredinidae (Hymenoptera: Tenthredinoidea) Supports the Monophyly of Eriocampinae stat. nov.
by Siying Wan, Xiao Li, Beibei Tan, Meicai Wei and Gengyun Niu
Biology 2026, 15(2), 202; https://doi.org/10.3390/biology15020202 - 22 Jan 2026
Viewed by 544
Abstract
Tenthredinidae (Hymenoptera: Tenthredinoidea), the most species-rich sawfly family, features a controversial subfamily classification, particularly regarding Eriocampa Hartig, 1837, Conaspidia Konow, 1898, and their relatives. In this study, we sequenced and characterized 15 complete mitochondrial genomes from Eriocampa, Eriocampopsis Takeuchi, 1952, and Conaspidia [...] Read more.
Tenthredinidae (Hymenoptera: Tenthredinoidea), the most species-rich sawfly family, features a controversial subfamily classification, particularly regarding Eriocampa Hartig, 1837, Conaspidia Konow, 1898, and their relatives. In this study, we sequenced and characterized 15 complete mitochondrial genomes from Eriocampa, Eriocampopsis Takeuchi, 1952, and Conaspidia, and reconstructed the phylogeny of Tenthredinidae using a mitogenomic dataset including 69 species from 16 subfamilies. The mitochondrial genomes of these genera exhibited genus-specific tRNA rearrangements within the IQM and ARNS1EF clusters. Phylogenetic analyses using both Maximum Likelihood and Bayesian Inference consistently recovered (Eriocampa + Eriocampopsis + Conaspidia) as a monophyletic lineage distinct from other subfamilies of Tenthredinidae. Divergence-time estimates indicate that the Eriocampa lineage diverged from other tenthredinids around the Late Cretaceous–Paleocene boundary (~70 Ma) and diversified during the Eocene. This timing coincides with the radiation of their host plants (Araliaceae, Betulaceae, and Juglandaceae). We also compared the morphology of Eriocampinae with that of other subfamilies of Tenthredinidae and summarized the diagnostic characters of Eriocampinae. Integrating morphological and mitogenomic evidence supports the recognition of Eriocampinae Rohwer, 1911 stat. nov. This study not only clarifies the phylogenetic position of these genera but also provides new insights into the coevolutionary history between sawflies and angiosperms. Full article
(This article belongs to the Special Issue Mitochondrial Genomics of Arthropods)
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24 pages, 8121 KB  
Article
Geochemical Characteristics and Geological Significance of Late Cretaceous to Paleocene Intermediate–Acidic Intrusive Rocks in the Qiuwo Area, Southern Margin of the Lhasa Terrane, China
by Min Jia, Fuwei Xie, Yibin Lin, Shuyuan Chen, Yang Yang and Jiancuo Luosang
Minerals 2026, 16(1), 63; https://doi.org/10.3390/min16010063 - 7 Jan 2026
Viewed by 396
Abstract
The Late Cretaceous to Paleocene magmatic evolution along the southern margin of the Lhasa Terrane records a critical transition from oceanic subduction to continental collision, yet its western segment remains underexplored. This study presents integrated petrographic, zircon U–Pb geochronological, zircon Hf isotopic, whole-rock [...] Read more.
The Late Cretaceous to Paleocene magmatic evolution along the southern margin of the Lhasa Terrane records a critical transition from oceanic subduction to continental collision, yet its western segment remains underexplored. This study presents integrated petrographic, zircon U–Pb geochronological, zircon Hf isotopic, whole-rock geochemical, and Sr–Nd isotopic data for three distinct phases of intermediate to felsic intrusions from the Qiuwo area in the western segment of the southern Lhasa terrane. The results reveal three distinct magmatic pulses: an early granodiorite emplaced at 89.9 ± 0.75 Ma, followed by a diorite crystallizing at 68.6 ± 0.56 Ma, and a late-stage granodiorite forming at 56.75 ± 0.43 Ma. All three rock units are metaluminous to weakly peraluminous (A/CNK < 1.1), sodic (Na2O > 3.2 wt.%), and dominated by amphibole, with zircon saturation temperatures of 737–786 °C, consistent with I-type granitoid affinity. All units are metaluminous (A/CNK = 0.92–1.00), calc-alkaline to high-K calc-alkaline, and enriched in LILE (K, Th, Rb) while depleted in HFSE (Nb, Ta, P, Ti), with moderate ΣREE (81–130 ppm), elevated (La/Yb)N (9.3–15.8), and negative Eu anomalies (δEu = 0.70–0.89). The early granodiorite is Na-rich (Na2O/K2O = 1.6), whereas the Paleocene granodiorite shows elevated K2O (3.2 wt.%) and reduced Na2O/K2O (~1.0), reflecting progressive crustal thickening and increasing magmatic differentiation. Zr and Hf are relatively enriched, and Sr/Y ratios decrease from 39 to 21, consistent with evolving magmatic conditions from deeper crustal melting in the Late Cretaceous to shallower, more evolved sources in the Paleocene. Zircon Hf isotopes reveal consistently positive εHf(t) values (+10.4 to +4.9), indicating derivation from juvenile basaltic lower crust. Sr–Nd isotopic data further demonstrate a systematic evolution: εNd(t) decreases from +2.7 to −0.1, while (87Sr/86Sr)i increases from 0.7044 to 0.7055, reflecting progressive incorporation of ancient crustal components into the magma source from the early Late Cretaceous to the Paleocene. These findings indicate that the Qiuwo intrusions formed by partial melting of a juvenile basaltic lower crust, with increasing crustal contamination during ascent and emplacement. The temporal progression of magmatism—spanning the waning stages of Neo-Tethyan subduction to the initial India–Eurasia collision (~55 Ma)—supports a model in which slab breakoff and lithospheric delamination triggered decompression melting of the lower crust, while assimilation of older crustal materials intensified as the continental collision progressed. This work provides key geochemical evidence for the transition from arc to post-collisional magmatism in the western Gangdese belt and refines the timing and mechanism of crustal growth in southern Tibet. Full article
(This article belongs to the Section Mineral Geochemistry and Geochronology)
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28 pages, 4613 KB  
Article
Mineralogy and Geochronology of Columbite–Tantalite Group Minerals from the Huangliangou Pegmatite in Western Yunnan, China: Implications for Formations and Ore Genesis
by Qianru Gao, Yuancan Ying, Haijun Yu, Fuchuan Chen and Wenchang Li
Minerals 2026, 16(1), 16; https://doi.org/10.3390/min16010016 - 23 Dec 2025
Viewed by 787
Abstract
The Huangliangou Nb-Ta-Be deposit in the Baoshan Block of western Yunnan hosts two distinct generations of columbite–tantalite group minerals (CGMs) and tapiolite, which record the evolution of a highly fractionated rare metal pegmatite. To investigate the relationship between Huangliangou pegmatite differentiation and Nb-Ta [...] Read more.
The Huangliangou Nb-Ta-Be deposit in the Baoshan Block of western Yunnan hosts two distinct generations of columbite–tantalite group minerals (CGMs) and tapiolite, which record the evolution of a highly fractionated rare metal pegmatite. To investigate the relationship between Huangliangou pegmatite differentiation and Nb-Ta mineralization, we conducted an integrated study combining petrography with mineral chemistry and geochronology. Electron probe microanalysis (EPMA) was used to determine the compositions of two CGMs and tapiolite. LA-ICP-MS U-Pb dating of these Nb-Ta oxides yields weighted mean ages of 60.25 ± 0.75 Ma for CGM-1 and 59.4 ± 1.1 Ma for CGM-2, indicating their synchronous formation in the early Paleocene. LA-ICP-MS trace element analysis of muscovite reveals a trend of decreasing Nb/Ta and K/Rb ratios with increasing Cs content from two-mica to garnet-bearing pegmatites. This chemical evolution in muscovite parallels the mineralogical transition from magmatic CGM-1 to metasomatic CGM-2 and tapiolite, confirming that late-stage hydrothermal fluids were characterized by volatile enrichment and Ta accumulation. The textural and chemical evolution reflects a late-stage, fluid-assisted autometasomatism within a highly fractionated melt. These results identify the northern garnet-bearing pegmatite dikes as a high-priority target for Ta exploration and provide a chrono-lithological framework for prospecting Paleocene pegmatite-type Nb-Ta deposits in western Yunnan and comparable Tethyan settings. Full article
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18 pages, 3232 KB  
Article
A Comparison of Generation–Retention–Expulsion in Felsic and Carbonate Laminated Shale by Semi-Open Thermal Pyrolysis: Implications for Shale Oil Exploration
by Quansheng Guan, Xiaoping Liu, Changwei Chen, Xianzheng Zhao, Fengming Jin, Wenya Jiang, Xiugang Pu, Biao Sun, Tian Liu, Zuxian Hua, Wendi Peng and Gaohang Jia
Geosciences 2026, 16(1), 9; https://doi.org/10.3390/geosciences16010009 - 22 Dec 2025
Viewed by 393
Abstract
Paleogene lacustrine shale is a key source rock for large oil reserves in China and a major target for shale oil exploration. However, differences in the chemical characteristics of felsic and carbonate shales during burial and thermal evolution remain poorly understood. This study [...] Read more.
Paleogene lacustrine shale is a key source rock for large oil reserves in China and a major target for shale oil exploration. However, differences in the chemical characteristics of felsic and carbonate shales during burial and thermal evolution remain poorly understood. This study evaluates hydrocarbon generation and expulsion efficiency in these shale types using pyrolysis experiments on lower Paleocene Kongdian Formation samples (Type I) from the Eastern China Sedimentary Basin. Results show that felsic shale has higher hydrocarbon generation capacity than carbonate shale. During pyrolysis, carbonate shale retained ~119 mg/g more oil but expelled 184 mg/g less than felsic shale. Felsic shale reached peak oil generation and retention faster but with lower retention efficiency. The larger volume of residual hydrocarbons in felsic shale facilitated earlier expulsion onset, higher yields of gaseous hydrocarbons, and superior gas expulsion efficiency. While both shales exhibited similar thermal evolution trends for hydrocarbon gases, methane proportions and gas-oil ratios (GOR) differed significantly. Carbon loss was comparable during the oil window, but felsic shale lost more carbon overall. At higher temperatures, n-alkanes in residual oil decreased sharply, with lighter oil retained at advanced maturity, increasing GOR and reducing heavy hydrocarbons. These findings demonstrate the effective hydrocarbon potential of medium-high TOC felsic and carbonate shales. Full article
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38 pages, 36010 KB  
Review
Cobalt-Rich Fe-Mn Crusts in the Western Pacific Magellan Seamount Trail: Geochemistry and Chronostratigraphy
by Igor S. Peretyazhko, Elena A. Savina and Irina A. Pulyaeva
Geosciences 2025, 15(11), 411; https://doi.org/10.3390/geosciences15110411 - 27 Oct 2025
Cited by 4 | Viewed by 1444
Abstract
Synthesis of published and new data from the Govorov and Kocebu guyots provide geochemical and chronostratigraphic constraints on hydrogenetic cobalt-rich Fe-Mn crusts from the Western Pacific Magellan Seamount Trail (MST). The history of the crusts began about 65–60 Ma, when the relict layer [...] Read more.
Synthesis of published and new data from the Govorov and Kocebu guyots provide geochemical and chronostratigraphic constraints on hydrogenetic cobalt-rich Fe-Mn crusts from the Western Pacific Magellan Seamount Trail (MST). The history of the crusts began about 65–60 Ma, when the relict layer R was deposited in the Campanian—Maastrichtian and Late Paleocene along the shores of guyots. The growth of the old-generation crusts continued in the Late Paleocene—Early Eocene (Layer I-1) and in the Middle—Late Eocene (Layer I-2) in a shallow-water shelf environment. The younger layers formed in the Late Oligocene—Early Miocene (Layer I-2b), Miocene (Layer II), and Pliocene—Pleistocene (Layer III) at depths about the present sea level. The precipitation of Fe and Mn oxyhydroxides from seawater was interrupted by several times, with the longest gap from 38 to 26.5 Ma between the old (R, I-1, and I-2) and young (I-2b, II, and III) layers. Fe and Mn oxyhydroxides in the crusts were affected by two global events of phosphogenesis in the Pacific: Late Eocene—Early Oligocene, from 43 to 39 Ma (Layers R, I-1, I-2) and Late Oligocene—Early Miocene, from 27 to 21 Ma (Layer I-2b). The trace element patterns in different layers of the Co-rich Fe-Mn crusts are grouped using factor analysis of principal components (varimax raw) into four factors: (1) +(all REEs except Ce and La); (2) +(Ce, La, Ba, Mo, Sr, Pb); (3) +(Zr, Hf, Nb, Rb, As)/-Pb; (4) +(U, Th, Co, As, Sb, W)/-Y. The factor score diagrams highlight fields which are especially contrasting for Layers I-1, I-2, and II + III according to factors 2 and 4. Consistent REE and Y variations in Layers I-2b → II → III of the crust from Pallada Guyot correlate with gradual ocean deepening between the Late Oligocene—Early Miocene and Present when the MST guyots were submerging. Large variations in the trace element contents across coeval layers may be due to the hydrodynamics of currents on the guyot surfaces. Furthermore, the geochemistry of the crusts bears effects from repeated episodes of Cenozoic volcanism in the MST region of the Pacific Plate. Higher contents of Nb, Zr, As, Sb, and W in the younger layers II and III may result from large-scale volcanism, including Miocene eruptions of petit-spot volcanoes. Full article
(This article belongs to the Section Geochemistry)
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25 pages, 46515 KB  
Article
Parental Affinities and Environments of Bauxite Genesis in the Salt Range, Northwestern Himalayas, Pakistan
by Muhammad Khubab, Michael Wagreich, Andrea Mindszenty, Shahid Iqbal, Katerina Schöpfer and Matee Ullah
Minerals 2025, 15(9), 993; https://doi.org/10.3390/min15090993 - 19 Sep 2025
Cited by 1 | Viewed by 1425
Abstract
As the residual products of severe chemical weathering, bauxite deposits serve both as essential economic Al-Fe resources and geochemical archives that reveal information about the parent rocks’ composition, paleoenvironments and paleoclimates, and the tectonic settings responsible for their genesis. The well-developed Early Paleocene [...] Read more.
As the residual products of severe chemical weathering, bauxite deposits serve both as essential economic Al-Fe resources and geochemical archives that reveal information about the parent rocks’ composition, paleoenvironments and paleoclimates, and the tectonic settings responsible for their genesis. The well-developed Early Paleocene bauxite deposits of the Salt Range, Pakistan, provide an opportunity for deciphering their ore genesis and parental affinities. The deposits occur as lenticular bodies and are typically composed of three consecutive stratigraphic facies from base to top: (1) massive dark-red facies (L-1), (2) composite conglomeratic–pisolitic facies (L-2), and (3) Kaolinite-rich clayey facies (L-3). Results from optical microscopy, X-ray powder diffraction (XRPD), and scanning electron microscopy with Energy-Dispersive X-Ray Spectroscopy (SEM-EDS) reveal that facies L-1 contains kaolinite, hematite, and goethite as major minerals, with minor amounts of muscovite, quartz, anatase, and rutile. In contrast, facies L-2 primarily consists of kaolinite, boehmite, hematite, gibbsite, goethite, alunite/natroalunite, and zaherite, with anatase, rutile, and quartz as minor constituents. L-3 is dominated by kaolinite, quartz, and anatase, while hematite and goethite exist in minor concentrations. Geochemical analysis reveals elevated concentrations of Al2O3, Fe2O3, SiO2, and TiO2. Trace elements, including Th, U, Ga, Y, Zr, Nb, Hf, V, and Cr, exhibit a positive trend across all sections when normalized to Upper Continental Crust (UCC) values. Field observations and analytical data suggest a polygenetic origin of these deposits. L-1 suggests in situ lateritization of some sort of precursor materials, with enrichment in stable and ultra-stable heavy minerals such as zircon, tourmaline, rutile, and monazite. This facies is mineralogically mature with bauxitic components, but lacks the typical bauxitic textures. In contrast, L-2 is texturally and mineralogically mature, characterized by various-sized pisoids and ooids within a microgranular-to-microclastic matrix. The L-3 mineralogy and texture suggest that the conditions were still favorable for bauxite formation. However, the ongoing tectonic activities and wet–dry climate cycles post-depositionally disrupted the bauxitization process. The accumulation of highly stable detrital minerals, such as zircon, rutile, tourmaline, and monazite, indicates prolonged weathering and multiple cycles of sedimentary reworking. These deposits have parental affinity with acidic-to-intermediate/-argillaceous rocks, resulting from the weathering of sediments derived from UCC sources, including cratonic sandstone and shale. Full article
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16 pages, 8282 KB  
Article
Petrographic, Geochemical, and Geochronological Characteristics of the Granite in Yunnan and Its Constraints on Ion-Adsorption Rare Earth Element Mineralization
by Bin Zhang, Haobin Niu, Linkui Zhang, Binhui Zhang, Xiangping Zhu, Rudong Gao, Yongfei Yang and Yinggui Zou
Minerals 2025, 15(8), 872; https://doi.org/10.3390/min15080872 - 19 Aug 2025
Cited by 1 | Viewed by 1259
Abstract
The TuguanZhai rare earth deposit in Tengchong, along with the Longan and Yingpanshan deposits in Longchuan, is a significant ion-adsorption type rare earth (iREE) deposit in Yunnan, China. Previous studies mainly focused on the geochemistry of residual regolith or the migration and enrichment [...] Read more.
The TuguanZhai rare earth deposit in Tengchong, along with the Longan and Yingpanshan deposits in Longchuan, is a significant ion-adsorption type rare earth (iREE) deposit in Yunnan, China. Previous studies mainly focused on the geochemistry of residual regolith or the migration and enrichment mechanism of rare earth elements (REEs), but lacked systematic analysis of the protoliths. To constrain this deposit and its protolith rock, called Tuguanzhai granite, we systematically integrate petrology features, petrogeochemistry, zircon U-Pb date, and artificial heavy mineral separation (AHMS). Specifically, iREE-host granites include two main periods in this area: the Early Cretaceous (112.13 ± 0.75 Ma) and the Paleocene–Eocene (52.78 ± 0.28 Ma, 48.56 ± 0.19 Ma). The former includes three types of biotite monzogranite with different grain sizes, and the latter is mainly medium-grained biotite monzogranite with local mylonitization. Geochemical features show that these granites generally share high alkalinity compositions (w(K2O + Na2O): 7.15 to 12.75 wt%) and potassium contents (w(K2O): 3.89 to 8.36 wt%). The mineralized granites exhibit significantly higher concentrations of the total REEs than non-mineralized granites, along with a strong enrichment of light REEs. Moreover, the results of AHMS reveal that the REE contents of apatite, allanite, and titanite in mineralized granites are 4.98, 1.29, and 1.90 times more abundant than in non-mineralized granites, respectively. Due to REEs being released from these REE-rich minerals in humid environments, there exists significant potential for iREE formation and exploration in the Early Cretaceous granites in western Yunnan. We innovatively propose the “abundance of easily leachable minerals” as a key indicator for iREE mineralization and exploration, having found it to be better than the traditional total REE contents. Full article
(This article belongs to the Special Issue Recent Developments in Rare Metal Mineral Deposits)
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13 pages, 3303 KB  
Article
Brachiopod Diversity and Paleoenvironmental Changes in the Paleogene: Comparing the Available Long-Term Patterns
by Dmitry A. Ruban
Diversity 2025, 17(8), 505; https://doi.org/10.3390/d17080505 - 23 Jul 2025
Cited by 2 | Viewed by 1336
Abstract
Recent updates to the reconstructions of Cenozoic environmental changes (global sea level, temperature, and atmospheric carbon dioxide content) have made it intriguing to compare them to paleontological records for original interpretations. Paleogene brachiopods have remained in the shadow of their Paleozoic–Mesozoic predecessors, and [...] Read more.
Recent updates to the reconstructions of Cenozoic environmental changes (global sea level, temperature, and atmospheric carbon dioxide content) have made it intriguing to compare them to paleontological records for original interpretations. Paleogene brachiopods have remained in the shadow of their Paleozoic–Mesozoic predecessors, and the reactions of their diversity to the Earth’s dramatic changes are poorly understood. The present work aims to fill this gap via a comparison of several diversity and paleoenvironmental curves. The generic diversity was established by stages with two essentially different paleontological datasets, and several fresh paleoenvironmental reconstructions were adopted. It was observed that neither Paleogene eustatic fluctuations nor changes in the atmospheric carbon dioxide content correspond well to the generic diversity dynamics of brachiopods. The changes in the total number of genera and the global temperatures demonstrate similarity at the Danian–Ypresian interval, but not later. The fluctuations in the brachiopod diversity are near the same level during the Eocene–Oligocene, despite strong paleoenvironmental changes, implying the intrinsic resistivity of these organisms to external influences. Additionally, the Cretaceous/Paleogene mass extinction, the Paleocene–Eocene thermal maximum, and the Early Eocene optimum could enhance the diversity dynamics together with the long-term temperature changes. In contrast, the influences of the Late Danian warming event and the Oi-1 glaciation were not observed. Full article
(This article belongs to the Section Phylogeny and Evolution)
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30 pages, 200218 KB  
Article
Tectonic Evolution and Structural Control of Dike-Hosted Orogenic Gold Deposits in the Yana–Kolyma Collision Orogen (Eastern Siberia): Insights from the Eastern Margin of the Siberian Craton
by Valery Yurievich Fridovsky and Maxim Vasilievich Kudrin
Geosciences 2025, 15(5), 168; https://doi.org/10.3390/geosciences15050168 - 7 May 2025
Viewed by 2132
Abstract
The Yana–Kolyma collision orogen, Eastern Siberia, is one of world-class gold economic belts, where large gold deposits are localized, mainly in the Upper Paleozoic and Lower Mesozoic clastic rocks. Dike-hosted orogenic gold deposits are found and to a lesser extent studied, but they [...] Read more.
The Yana–Kolyma collision orogen, Eastern Siberia, is one of world-class gold economic belts, where large gold deposits are localized, mainly in the Upper Paleozoic and Lower Mesozoic clastic rocks. Dike-hosted orogenic gold deposits are found and to a lesser extent studied, but they are important for understanding the structural control of mineralization within the framework of the orogen. Orogenic gold deposits of the Vyun ore field are hosted in Kimmeridgian–Titonian mafic, intermediate and felsic dikes, but they have no genetic connection with dikes. The late formation of deposits led to the fact that previously reactivated polydeformed structures were subsequently mineralized. The study of the structural control of mineralization is also complicated by superimposed late tectonic events. Based on the analysis of collected field materials, this paper presents the results of the study of deformation structures of the Vyun ore field within the framework of the Mesozoic evolution history throughout the geological time of the eastern convergent margin of the Siberian Craton. Four stages of deformations are identified. The pre-mineralization deformations and metamorphic and magmatic events share a common NE-SW shortening (D1 phase), which is related to the subduction of the Oymyakon oceanic slab and collision of the Kolyma–Omolon superterrane from the eastern margin of the Siberian Craton. This first stage is characterized by the superposition of several tectonic events under conditions of compression and progressive deformations (D1/1 and D1/2). Ore mineralization was formed at the end of compression in the same stress field (D1/2). Its structural control is determined by reactivation of older dikes and faults. Dikes are areas of heterogeneous stress and heterogeneous strain, being favorable for the concentration of ore fluids. The metallogenic time of formation of the gold mineralization is synchronous with the tectonic event, which likely reflects the final stages of the Kolyma–Omolon microcontinent–Siberian Craton collision of the Valanginian during crustal thickening. The main impulse of the Au mineralization D1/2 phase coincided with a slowdown in convergence. The post-mineralization tectonic regime was related to the Aptian–Late Cretaceous tectonic transition from compression to transpression. Transpressional tectonics were determined accordingly by W-E (D2 phase) and N-S (D3 phase) stress fields caused by several accretion events in the Cretaceous on the northern and eastern margins of Siberia. D4 phase extensional structures were caused by the opening of the Eurasian Oceanic basin in the Arctic in the Paleocene. The obtained results have a first-order impact on the understanding of the structural control of orogenic gold deposits and their relationship to the evolution of the host orogen. The new findings improve the tectonic knowledge of an area of interest for ore deposit exploration targeting orogenic gold deposits in Phanerozoic terranes of craton margins. Full article
(This article belongs to the Section Structural Geology and Tectonics)
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16 pages, 2377 KB  
Article
Complete Mitochondrial Genome of Chlorogomphus papilio (Odonata: Anisoptera: Chlorogomphidae) and Phylogenetic Analyses
by Xiaoxiao Jin, Xiaojia Lin, Simeng Wang and Jie Fang
Biology 2025, 14(5), 493; https://doi.org/10.3390/biology14050493 - 1 May 2025
Viewed by 1171
Abstract
This study aimed to elucidate the mitochondrial genome organization of Chlorogomphus papilio and the phylogenetic relationships of Chlorogomphidae. We used the Illumina MiSeq sequencing platform to sequence the mitochondrial genome of C. papilio, which was subsequently assembled, annotated, and analyzed. Bayesian inference, [...] Read more.
This study aimed to elucidate the mitochondrial genome organization of Chlorogomphus papilio and the phylogenetic relationships of Chlorogomphidae. We used the Illumina MiSeq sequencing platform to sequence the mitochondrial genome of C. papilio, which was subsequently assembled, annotated, and analyzed. Bayesian inference, maximum likelihood, and maximum parsimony methods were employed to construct the mitochondrial phylogenetic tree of 25 species of Chlorogomphidae based on 16S rRNA and cox1 genes. We observed that the mitochondrial genome of C. papilio is 15,251 bp in length and includes 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and a non-coding control region. All PCGs start with a typical ATN codon. While cox1, cox2, cox3, and nad5 end with an incomplete termination codon (T), the remaining PCGs terminate with TAG. The secondary structure of the 22 tRNAs showed that only the trnS1 gene lacked the dihydrouracil arm (DHU arm), whereas the rest formed a typical cloverleaf structure. Additionally, 32 G-U mismatches were observed in the secondary structure. Phylogenetic analyses indicated that C. papilio and C. magnificus are sister species. Divergence time analyses indicated that Chlorogomphidae originated around 111.04 Ma, with C. papilio diverging from the common ancestor shared with C. magnificus approximately 58.51 Ma. This divergence is likely linked to the Paleocene–Eocene Thermal Maximum (PETM) and the tectonic uplift of the Himalayas, which created warm, humid habitats and contributed to geographic isolation. This study contributes to a better understanding of the mitochondrial genome and phylogeny of C. papilio, providing valuable molecular markers for further genetic studies. Full article
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22 pages, 41247 KB  
Article
Hydrocarbon Accumulation Characteristics of the Perdido Fold Belt, Burgos Basin, Gulf of Mexico—A Comparison Between the Central and Eastern Regions
by Yan Fan, Caifu Xiang, Songling Yang, Aishan Li, Liang Chen, Lin’an Pang, Jingtan Chen and Minghui Yang
Energies 2025, 18(7), 1834; https://doi.org/10.3390/en18071834 - 4 Apr 2025
Cited by 1 | Viewed by 1724
Abstract
Frequent salt tectonic activities within the Perdido fold belt complicate hydrocarbon accumulation, severely constraining hydrocarbon exploration. In this paper, the characteristics and differences of hydrocarbon accumulation in the Wilcox and Frio Formations in the central and eastern regions of the Perdido fold belt [...] Read more.
Frequent salt tectonic activities within the Perdido fold belt complicate hydrocarbon accumulation, severely constraining hydrocarbon exploration. In this paper, the characteristics and differences of hydrocarbon accumulation in the Wilcox and Frio Formations in the central and eastern regions of the Perdido fold belt are analyzed through geochemical analysis, hydrocarbon generation simulation, and regional tectonic restoration. The results indicate the following: (1) Hydrocarbon in the Wilcox and Frio Formations in both the central and eastern regions of the Perdido fold belt originates from the Jurassic Tithonian source rocks. (2) Source rocks in the central and eastern regions entered the oil generation threshold in the late Paleocene and reached the oil generation peak in the late Eocene. Compared with the central region, the eastern region reached the gas generation threshold earlier, which is influenced by the activities and differential distribution of salt in the Perdido fold belt. (3) Hydrocarbon accumulation in central and eastern regions is divided into four stages, showing a “terraced single-layer” and “dual-layer” accumulation pattern in the central and eastern regions of the Perdido fold belt, respectively. (4) Central and eastern regions represent discrepancies in the petroleum systems elements of reservoirs, caprocks, traps, generation, charging, and preservation of hydrocarbon. Full article
(This article belongs to the Special Issue Petroleum Exploration, Development and Transportation)
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37 pages, 21085 KB  
Article
Unraveling the Protracted Magmatic Evolution in the Central Urumieh–Dokhtar Magmatic Arc (Northeast Saveh, Iran): Zircon U-Pb Dating, Lu-Hf Isotopes, and Geochemical Constraints
by Mohammad Goudarzi, Hassan Zamanian, Urs Klötzli, Jiří Sláma, Jitka Míková, Jolanta Burda, David R. Lentz, Matee Ullah and Jiranan Homnan
Minerals 2025, 15(4), 375; https://doi.org/10.3390/min15040375 - 3 Apr 2025
Cited by 3 | Viewed by 2914
Abstract
Cenozoic plutonic rocks in northeast Saveh, part of the central Urumieh–Dokhtar Magmatic Arc (UDMA) in Iran, comprise monzonite, monzodiorite, gabbro, and gabbrodiorite. Geochemical, zircon U-Pb geochronology, and Hf isotopic data reveal that these plutonic rocks belong to a medium-K calc-alkaline, metaluminous series with [...] Read more.
Cenozoic plutonic rocks in northeast Saveh, part of the central Urumieh–Dokhtar Magmatic Arc (UDMA) in Iran, comprise monzonite, monzodiorite, gabbro, and gabbrodiorite. Geochemical, zircon U-Pb geochronology, and Hf isotopic data reveal that these plutonic rocks belong to a medium-K calc-alkaline, metaluminous series with arc-related signatures. Zircon U-Pb ages (ca. 60 to 3 Ma) indicate prolonged magmatic evolution from the Middle Paleocene to the Middle Pliocene. Contrary to earlier reports of a 15 Ma period of reduced magmatic activity (ca. 72–57 Ma), our data indicate a shorter interval (ca. 10–12 Ma) during which magmatic activity decreased significantly. Key magmatic pulses occurred during the Late Eocene (ca. 40–47 Ma), Early Miocene (ca. 23–18 Ma), and Late Miocene–Pliocene (ca. 11–5.2 Ma), with geochemical data indicating a subduction-related origin. The most recent magmatic pulses in the central UDMA, potentially extending across the entire UDMA, are dated between 5 and 2.5 Ma, identified in a cluster of zircons from gabbroic rocks, which could correspond to the concluding stages of slab steepening related to continental subduction. Zircon εHf(t) values (−11.43 to 12.5) and geochemical data suggest fractional crystallization, crustal assimilation, and mantle-derived melts. The clinopyroxene crystallization temperatures (1150–1200 °C) and supporting geochemical data imply that magma was produced in a metasomatized spinel–lherzolite mantle at depths <80 km. This generation is associated with asthenospheric upwelling and slab rollback, which, in turn, triggered the partial melting of the lithosphere and fueled the region’s magmatic activity. Full article
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20 pages, 6580 KB  
Article
Deformation and Evolution of Akata Formation Mudstone in the Niger Delta Basin: Insights from Analogue Models
by Shuaiyu Shi, Wenlong Ding, Yixin Yu and Jixin Zhang
J. Mar. Sci. Eng. 2025, 13(3), 590; https://doi.org/10.3390/jmse13030590 - 17 Mar 2025
Cited by 1 | Viewed by 2284
Abstract
The Niger Basin is a typical marginal basin with complex internal structures and abundant oil and gas resources, exhibiting unique marine geological characteristics and processes. The distribution and deformation characteristics of Akata Formation mudstone in the basin significantly influence hydrocarbon accumulation. In this [...] Read more.
The Niger Basin is a typical marginal basin with complex internal structures and abundant oil and gas resources, exhibiting unique marine geological characteristics and processes. The distribution and deformation characteristics of Akata Formation mudstone in the basin significantly influence hydrocarbon accumulation. In this study, four analogue models were used to analyze the main factors affecting mudstone tectonics and establish an evolution model of mudstone structures. The results show that the tectonic features in the basin reflect the combined influence of gravity sliding and spreading. The main mechanism driving mudstone deformation is gravity spreading caused by differential loading. The basement morphology is the decisive factor in the development of zonation involving extension, translation, and contraction zones. The development of mudstone structures is also affected by the inclination of the basement slope and the thicknesses of both the mudstone layer and overlying layers. A relatively large basement slope inclination is conducive to the rapid flow of mudstone, leading to the rapid development of mudstone formations. A thin mudstone layer with weak plastic mobility is favorable for the full development of mudstone formations. A relatively thick overburden leads to enhanced gravity spreading, which in turn leads to the formation of larger and more numerous mudstone structures. The formation and evolution of mudstone structures in the Niger Basin involved through three stages: (1) during the Paleocene–Middle Oligocene, thick marine mudstone was deposited; (2) in the Middle Oligocene–Late Oligocene, the mudstone and overlying layers were strongly deformed, and numerous mudstone structures developed with tectonic zonation; and (3) since the Pliocene, the tectonic activity in the basin weakened. The simulation of the evolutionary process and evolutionary model established in this study improves the understanding of mudstone tectonics and provides a reference for analyzing the genetic mechanism and hydrocarbon exploration in the basin. Full article
(This article belongs to the Topic Basin Analysis and Modelling)
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