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The characteristics and evolution of fibrous calcite veins in organic-rich shales have gained significant attention due to the recent advancements in shale oil and gas exploration. However, the fibrous calcite veins in the Upper Permian Dalong Formation remain lacking in awareness. To investigate the formation and significance of bedding-parallel fibrous calcite veins in the Dalong Formation, we conducted an extensive study utilizing petrography, geochemistry, isotopic analysis, and fluid inclusion studies on outcrops of the Dalong Formation in South China. Our findings reveal that fibrous calcite veins predominantly develop in the middle section of the Dalong Formation, specifically within the transitional interval between siliceous and calcareous shales, characterized by symmetric, antitaxial fibrous calcite veins. The δ¹³C values of these veins exhibit a broad range (−4.53‰ to +3.39‰) and display a decreasing trend in the directions of fiber growth from the central part, indicating an increased contribution of organic carbon to the calcite veins. Additionally, a consistent increase in trace element concentrations from the central part toward the fiber growth directions suggests a singular fluid source in a relatively closed environment, while other samples exhibit no distinct pattern, possibly due to the mixing of fluids from multiple layers resulting from repeated opening and closing of bedding-parallel fractures in the shales. The notable difference in δEu between the fibers on either side of the median zone indicates that previously formed veins acted as barriers, impeding the mixing of fluids, with the variation in δEu reflecting the differing sedimentary properties of the surrounding rocks. The in situ U-Pb dating of fibrous calcite veins yields an absolute age of 211 ± 23 Ma, signifying formation during the Late Triassic, which correlates with a shale maturity of 1.0‰ to 1.25‰. This integrated study suggests that the geochemical records of fibrous calcite veins document the processes related to overpressure generation and the opening and healing of bedding-parallel fractures within the Dalong Formation. Full article

Widespread Triassic granitic magmatism is archived in the East Kunlun Orogen Belt (EKOB) of Northern Qinghai–Tibet Plateau. Mafic magmatic enclaves (MMEs), commonly hosted in these plutons, are generally interpreted as products of magma mixing; however, the specific magmatic processes remain poorly understood. In this study, we present new data on the complex zoning patterns, in situ U–Pb ages, trace element compositions, and Nd isotopic characteristics of titanite grains from the MMEs and host granodiorite of Laningzaohuo Zhongyou pluton. Whole-rock geochemical data indicate that the pluton is composed of volcanic arc-related, calc-alkaline, metaluminous I-type granodiorite. Titanite in the MMEs and the granodiorite yield similar U–Pb ages of ~244 Ma but display distinct textural and compositional features. Titanite from the granodiorite is typically euhedral, characterized by magmatic core and mantle with deuteric rim, and exhibits sector and fir-tree zoning in the core. In contrast, titanite from the MMEs is generally anhedral, also showing magmatic core and mantle as well as deuteric rims, but exhibits oscillatory zoning and incomplete sector and fir-tree zoning in the core. Titanite cores in the MMEs have ε_Nd(t) ranging from −2.5 to −3.4, comparable to those of the coeval gabbro and MMEs elsewhere in the EKOB. These cores also show higher LREE/HREE ratios compared to titanite cores in the granodiorite, suggesting crystallization from mixed magmas with greater contributions from enriched lithospheric mantle sources. Titanite mantles in the MMEs yield ε_Nd(t) of −4.0 to −4.8, slightly lower than the cores in the MMEs but higher than those of titanite cores and mantles in the granodiorite (−4.6 to −5.5). The mantle can be interpreted as crystallized from mixed magmas with less mafic components. Titanite rims in the MMEs have ε_Nd(t) of −5.0 to −5.7, identical to those in the granodiorite, and have REE concentrations and Th/U and Nb/Ta ratios consistent with the titanite rims in the granodiorite, clearly indicative of crystallization from evolved, hydrated, granodioritic magmas. Plagioclase in the MMEs exhibits disequilibrium textures such as sieve texture and reverse zoning, with An_36–66, contrasting with the more uniform An contents (An_35–37) in the granodiorite. This suggests that plagioclase in the MMEs crystallized in an environment influenced by both mafic and felsic magmas. Amphibole thermobarometry indicates that amphibole in the MMEs crystallized at ~788 °C and ~295 MPa, slightly higher than the crystallization conditions in the granodiorite (~778 °C and ~259 MPa). We thus propose that the chemical and textural differences between titanite in the MMEs and granodiorite suggest that the MMEs formed within a mushy hybrid layer generated by injection of upwelling basaltic magma into a pre-existing granitic magma chamber. Titanite cores and mantles in the MMEs likely crystallized from variably mixed magmas. They subsequently underwent resorption and disequilibrium growth within the hybrid layer, and were eventually overgrown by rims formed from evolved interstitial granitic melts within the mushy enclaves. These findings demonstrate that the complex zoning and geochemical titanite in the MMEs provide valuable insights into magma mixing processes. Full article

Zearalenone (ZEN) is a widespread estrogenic mycotoxin that poses serious health risks to both humans and animals through the contamination of cereals and feeds. In this study, a novel Bacillus strain X13 was isolated from volcanic rock soil and demonstrated the unique ability to utilize ZEN as the sole carbon source for growth and metabolism. Under optimized conditions (37 °C, pH 8.0, and 5% inoculum in M9 minimal medium), strain X13 achieved a ZEN degradation efficiency of 98.57%. LC-MS analysis identified 1-(3,5-dihydroxyphenyl)-6′-hydroxy-1′-undecen-10′-one as the primary degradation product, indicating enzymatic hydrolysis of the lactone ring. Enzymatic assays revealed that the active components were extracellular, proteinaceous, and metal ion-dependent. Furthermore, the strain reduced ZEN content in mold-contaminated corn flour by 74.6%, effectively lowering toxin levels below regulatory limits. These findings suggest that Bacillus sp. X13 is a promising candidate for the bioremediation of ZEN-contaminated agricultural products, with significant potential for application in food and feed detoxification strategies. The robust degradation performance of strain X13 under simulated environmental conditions, combined with its adaptability to agricultural substrates, positions it as a viable solution for large-scale mycotoxin mitigation in the food industry chain, from pre-harvest field management to post-harvest storage processing. Full article

Non-destructive tests are especially useful for the assessment of building stones and their deterioration in built cultural heritage. Gamma-ray spectrometry is a non-destructive test that has not been applied extensively in these types of constructions. Therefore, the purpose of this study is to show the results of gamma-ray spectrometry for limestone characterization and deterioration assessment. This study was conducted in the North Temple of the Archaeological Zone of Chichen Itza and several outcrops in the area. Gamma-ray spectrometry data were corrected for attenuation caused by the moisture content in rocks to calculate the real radioelements concentrations using linear regression, with interpretation based on their mobility resulting from chemical weathering processes. The results obtained with gamma-ray spectrometry were corroborated by laboratory analyses, demonstrating that stones from the North Temple are more weathered than rocks from the outcrops, and that some limestones have clasts derived from terrigenous sources, causing them to show slightly higher radiation, which can be distinguished easily with gamma-ray spectrometry, even when lithology cannot be recognized in plain sight. Gamma-ray spectrometry proved to be useful for limestone characterization, and data obtained can be correlated with parameters from other analyses. Full article

Accurate and efficient rock mass characterization is essential in geotechnical engineering, yet traditional tunnel face mapping remains time consuming, subjective, and potentially hazardous. Recent advances in digital technologies and AI offer automation opportunities, but many existing solutions are hindered by slow 3D scanning, computationally intensive processing, and limited integration flexibility. This paper presents Tunnel Rapid AI Classification (TRaiC), an open-source MATLAB-based platform for rapid and automated tunnel face mapping. TRaiC integrates single-shot 360° panoramic photography, AI-powered discontinuity detection, 3D textured digital twin generation, rock mass discontinuity characterization, and Retrieval-Augmented Generation with Large Language Models (RAG-LLM) for automated geological interpretation and standardized reporting. The modular eight-stage workflow includes simplified 3D modeling, trace segmentation, 3D joint network analysis, and rock mass classification using RMR, with outputs optimized for Geo-BIM integration. Initial evaluations indicate substantial reductions in processing time and expert assessment workload. Producing a lightweight yet high-fidelity digital twin, TRaiC enables computational efficiency, transparency, and reproducibility, serving as a foundation for future AI-assisted geotechnical engineering research. Its graphical user interface and well-structured open-source code make it accessible to users ranging from beginners to advanced researchers. Full article

Strontium, a key trace element regulating bone development and cardiovascular function, has seen growing research interest in its groundwater accumulation and resource potential. The unique geological structure of the northern Lushan Mountain slope provides an ideal setting to investigate strontium migration and enrichment. We systematically collected 21 groundwater samples and analyzed strontium occurrence characteristics and formation mechanisms using hydrochemical analysis, PHREEQC simulations, Gibbs diagrams, and cation exchange adsorption models. Analysis revealed that 71.4% of samples (15 groups) exceeded the GB 8537-2018 standard (≥0.4 mg/L), significantly higher than typical groundwater systems. Spatial distribution showed marked geological differentiation: average strontium concentration in Cambrian-Ordovician fractured-karst water reached 2.79 mg/L (range: 0.207–12.41 mg/L), 109.8% higher than in bedrock fissure water (1.33 mg/L). Structural control was evident, with samples near fault zones exhibiting generally higher concentrations than non-fault areas. Multivariate statistics indicated significant positive correlations between Sr²⁺ and TDS, Na⁺, Ca²⁺, and SO₄²⁻, suggesting synergistic enrichment mechanisms. Hydrogeochemical simulations confirmed that multiphase leaching of strontium-bearing silicate rocks provides the primary source, while rock weathering-driven ion exchange reactions constitute the key enrichment mechanism. This study elucidates the structural-lithological coupling-controlled hydrogeochemical cycle of strontium, providing theoretical support for delineating high-quality mineral water targets and developing health-beneficial geo-resources in the Lushan region. Full article

This study focuses on the genesis mechanism of thermal anomalies in the southwestern part of the Anan Depression in the Erlian Basin. Based on magnetotelluric 3D inversion data, a high-resolution electrical resistivity structure model was constructed, revealing the spatial configuration of deep heat sources and thermal pathways. The main conclusions are as follows: (1) Magnetotelluric 3D imaging reveals an elliptical low-resistivity anomaly (Anomaly C: 20 km × 16 km × 5 km, 0–5 Ωm) at depths of ~10–15 km. This anomaly is interpreted as a hypersaline fluid (approximately 400 °C, ~1.5% volume fraction, 3–5 wt.% NaCl), acting as the primary heat source. (2) Upward migration along F1/F3 fault conduits (10–40 Ωm) establishes a continuous pathway to mid-depth reservoirs D1/D2 (~5 km, 5–10 Ωm) and shallow crust. An overlying high-resistivity caprock (40–100 Ωm) seals thermal energy, forming a convective “source-conduit-reservoir-cap” system. (3) Integrated seismic data reveal that heat from the Abaga volcanic melt supplements Anomaly C via conduction through these conduits, combining with mantle-derived heat to form a composite source. This research delineates the interacting genesis mechanism of “deep low-resistivity heat source—medium-low resistivity fault conduit—shallow low-resistivity reservoir—relatively high-resistivity cap rock” in the southwestern A’nan Sag, providing a scientific basis for optimizing geothermal exploration targets and assessing resource potential. Full article

Rock grade is a key indicator guiding tunnel construction. In order to ensure the efficiency and safety of construction, it is necessary to accurately predict the rock grade of the unexcavated part of a tunnel. Currently, geological sketches and geophysical exploration methods can be employed to obtain multi-source and heterogeneous detection data. However, the key challenge lies in how to integrate various types of exploration data to predict the rock grade, which is the focus of the current research. In this paper, we propose a multi-source information fusion-based rock-grade hybrid model for the tunnel construction process. The proposed approach consists of several steps. In the first step, homogenization processing of the acquired multi-source and heterogeneous data, such as geological and TSP (Tunnel Seismic Prediction) detection data, is performed. This primarily includes feature extraction, spatial registration, and the filtering of anomalous data, aimed at enhancing the quality of the data. In the second step, considering the variations in the geological conditions of the construction face, this paper first stratifies the rock grades at the construction face. Subsequently, utilizing TSP detection data, a rock-grade prediction model is established by combining knowledge-driven and data-driven approaches. In the third step, based on the rock grade predictions obtained from the rock grade forecasting model established in the second step, an intelligent decision-making process is conducted by comparing these predictions with the rock grades anticipated during the design stage. This results in the determination of the final rock grade. Finally, the effectiveness of the proposed method is validated through comparison with experimental results. Full article

Rare earth elements (REYs) are crucial components of billions of products worldwide. Transitioning from foreign to domestic REY sources requires utilizing both primary (i.e., carbonatites, alkaline igneous rocks, pegmatites, skarn deposits) and secondary (unconventional) sources (i.e., ion-adsorption clays, placer deposits, weathered rock, black and/or oil shales). Coal and coal-bearing strata, promising secondary REY resources, are the focus of this study. Understanding REY mineral associations in unconventional resources is essential to quantifying resource volume and identifying viable mineral separation and processing techniques. Highly REY-enriched (>750 ppm) coal or mudstone samples from the Uinta Region, Utah, USA, were selected for scanning electron microscopy (SEM) analysis. Energy dispersive X-ray spectroscopy (EDS)-determined REY enrichment occurs in: (1) a silt-size fraction (5–30 μm) of monazite and xenotime REY-enriched grains, (2) a clay-size fraction (2–5 μm) of monazite REY-enriched grains dispersed in the clay-rich matrix, and (3) organically confined REY domains < 2 μm. Findings suggest possible REY enrichment from multiple sources, including: (1) detrital silt-size grains, (2) volcanic ash fall, largely in clay-size grains, and (3) organic REY uptake in the peat swamp depositional environment. Full article

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 study investigates geothermal clusters in the middle reaches of the Dawen River Basin, focusing on the developmental characteristics and genetic mechanisms of typical geothermal water exposures at key sites, including Daidaoan (Taishan), Qiaogou (Culai Town), and Anjiazhuang (Feicheng). Utilizing hydrogeochemical and environmental isotope analyses, we identify a dual groundwater recharge mechanism: (1) rapid infiltration via preferential flow through fissure media and (2) slow seepage with evaporative loss along gas-bearing zones. Ion sources are influenced by water–rock interactions and positive cation exchange. The hydrochemical types of surface water and geothermal water can be divided into five categories, with little difference within the same geothermal area. The thermal reservoir temperatures range from 53.54 to 101.49 °C, with the Anjiazhuang and Qiaogou geothermal areas displaying higher temperatures than the Daidaoan area. Isotope calculations indicate that the recharge elevation ranges from 2865.76 to 4126.69 m. The proportion of cold water mixed in the shallow part is relatively large. A comparative analysis of the genetic models of the three geothermal water groups shows that they share the common feature of being controlled by fault zones. However, they differ in that the Daidao’an geothermal area in Mount Tai is of the karst spring type with a relatively low geothermal water temperature, whereas the Qiaogou geothermal area in Culai Town and the Anjiazhuang geothermal area in Feicheng are of the gravel or sandy shale spring types with a relatively high geothermal water temperature. Full article

Deep shale gas reservoirs are vital sources of unconventional natural gas and present unique challenges for exploration and development due to their multiscale flow characteristics and elastoplastic deformation behavior of reservoir rocks. Accurately predicting permeability in these reservoirs is crucial. This study introduces a novel model utilizing fractal theory and a thick-walled cylinder model to characterize stress-dependent apparent gas permeability. The model incorporates various flow mechanisms, including viscous flow, transition flow, Knudsen diffusion, surface diffusion, real gas effects, and gas slip effects. It enables predictions of how permeability changes with elastoplastic behavior and affects the pore volume fractions of different flow mechanisms. Experimental validation during elastic and elastoplastic deformations confirms the model’s accuracy, with each parameter having clear physical significance. Key findings reveal that, at the same effective stress, apparent gas permeability increases with pore radius fractal dimension, temperature, and Young’s modulus, while decreasing with capillary tortuosity fractal dimension. Additionally, during plastic deformation, greater magnitudes of plastic strain lead to more pronounced changes in apparent gas permeability compared to elastic deformation. These insights emphasize the importance of incorporating elastoplastic behavior in studies of deep shale gas reservoirs. Full article

The construction of large underground caverns fundamentally differs from building and above ground civil infrastructure projects due to their complex geometries and variable geological conditions. These projects are complex and challenging because a large amount of data is generated from dispersed, independent, and heterogeneous sources. The underground construction industry often uses traditional project management techniques to manage complex interactions between these data sources that are hardly linked, and independent decisions are often made without considering all the relevant aspects. In this context, cavern construction exhibits uncertainties and risks due to unforeseen circumstances, an intricate design, and ineffective information management. Existing research has considered general BIM semantic models at the design stage; however, the digital transformation of cavern construction remains underdeveloped and fails to integrate digital construction throughout the project lifecycle. To address that gap, a novel BIM-based multi-model cavern information modeling framework is presented here to improve project management, construction, and delivery by integrating multiple interlinked data models and project performance data for large underground cavern construction. Data models of cavern construction processes are linked to propose an extension of the Industry Foundation Classes (IFC) schema based on the cavern-specific elements, relationships, and property set definitions. To illustrate the potential of the proposed framework, a theoretical application to the powerhouse cavern construction is presented. The results indicate that the framework has significant potential to improve construction efficiency and safety and establish a robust foundation for the digital transformation of underground cavern projects. The theoretical implementation on the Neelum–Jhelum powerhouse cavern showed that the framework enabled a 92 m cavern realignment to avoid fault zones, achieved a 12.4% reduction in rock bolt usage, and a 9.8% reduction in shotcrete volume. These quantitative improvements illustrate its potential to enhance safety, reduce material costs, and optimize construction efficiency compared to conventional workflows. Full article

This study presents the first integrated, basin-scale analysis of helium distribution and its geological controls within the Ordos Basin, one of China’s most prospective cratonic gas provinces. Through comprehensive sampling and experimental analysis of the helium content in natural gas, combined with high-resolution gravity and magnetic data processed using the normalized vertical derivative of the total horizontal derivative (NVDR-THDR) method, we reveal significant spatial heterogeneity in helium enrichment. The results show that helium concentrations are generally higher along the basin margins and structurally complex zones, while central areas are relatively depleted. Helium primarily originates from the radioactive decay of uranium (U) and thorium (Th) within metamorphic and magmatic basement rocks. Fault systems act as efficient vertical migration pathways, enabling deep-sourced helium to accumulate in structurally and stratigraphically favorable traps. This study proposes a new enrichment mode, “basement-sourced helium generation, fault-mediated migration, and caprock-controlled preservation”, which highlights the synergistic roles of basement lithology, deep-seated faults, and sealing capacity in controlling helium distribution. This model is supported by the observed alignment of high helium concentrations with zones of strong basement magnetism and major fault intersections. These findings advance our understanding of helium accumulation mechanisms in stable cratonic settings and provide a predictive framework for helium exploration in similar geological contexts worldwide. Full article

Public health in a densely populated city is inextricably linked to the state of the urban environment. The microclimate, the condition of water sources and sanitary well-being are just some of the many environmental factors that have a strong influence on people’s health. The presence of urban green spaces and various birds in cities is extremely important, also to create a more favorable psychological atmosphere for the people who live and/or work there. At the same time, it should not be forgotten that the feces of synanthropic birds are a favorable environment for various potentially pathogenic species of microorganisms, including yeasts of the genus Candida. Here, we investigated the culturable, potentially pathogenic ascomycetous yeast microbiome in the fresh and dry feces of five synanthropic birds (Rock Pigeon, European Starling, White Wagtail, Great Tit and House Sparrow). The samples were collected in spring (May 2024). In total, 48 Rock Pigeon, 47 European Starling, 38 White Wagtail, 32 Great Tit and 30 House Sparrow droppings were collected and analyzed. The selective medium Brilliance Candida Agar was used for cultivation. A total of 638 strains were isolated belonging to 9 yeast species (Arxiozyma bovina, Candida albicans, Nakaseomyces glabratus, Clavispora lusitaniae, C. tropicalis, C. parapsilosis, Pichia kudriavzevii, Debaryomyces hansenii and D. fabryi). All detected yeast species were molecularly identified using the ITS rDNA region. The microbiome of potential pathogens in fresh feces proved to be significantly host-dependent. Most pathogenic yeasts (7 species)—A. bovina, C. albicans, N. glabratus, Cl. lusitaniae, C. tropicalis, C. parapsilosis and P. kudriavzevii—were only detected in fresh feces from pigeons. This list contains five out of six ascomycetous species from the list of critical, high and medium-important yeast pathogens published in the World Health Organization fungal list. Of the potentially pathogenic yeasts, two species were observed in the dry droppings of various birds: C. parapsilosis and P. kudriavzevii. No significant differences in the diversity of culturable pathogens in dry droppings were observed between the different hosts. Fresh droppings from synanthropic birds, especially pigeons (and to a lesser extent dry droppings), therefore pose a health risk. In this study, we did not find any feces from synanthropic birds in which potentially pathogenic ascomycetous yeasts were not detected. To maintain the sanitary safety and well-being of citizens, it is very important to regulate the number of synanthropic birds (primarily pigeons), especially in sensitive areas such as playgrounds, hospital territories, etc. Full article