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Search Results (2,796)

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Keywords = mineral exploration

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19 pages, 284 KiB  
Review
Enhancing Meat Quality and Nutritional Value in Monogastric Livestock Using Sustainable Novel Feed Ingredients
by José A. M. Prates
Foods 2025, 14(2), 146; https://doi.org/10.3390/foods14020146 - 7 Jan 2025
Viewed by 118
Abstract
This study explores the potential of novel feed ingredients for monogastric animals, such as pigs and poultry, to enhance meat quality and nutritional value while reducing the environmental footprint of production. Innovative feed options like black soldier fly larvae, Schizochytrium microalga, Laminaria seaweed, [...] Read more.
This study explores the potential of novel feed ingredients for monogastric animals, such as pigs and poultry, to enhance meat quality and nutritional value while reducing the environmental footprint of production. Innovative feed options like black soldier fly larvae, Schizochytrium microalga, Laminaria seaweed, fermented soybean hulls, fortified flaxseed and grape pomace have significantly improved meat quality and nutritional traits. Results indicate that these ingredients enrich meat with omega-3 fatty acids, antioxidants, vitamins and minerals, enhancing nutritional value while improving sensory traits such as flavour, tenderness and colour. For instance, including Laminaria seaweed increased iodine content by up to 45%, while Schizochytrium microalga improved omega-3 deposition by over 70%. The inclusion of grape pomace enhanced oxidative stability and extended meat shelf life. This review also discusses the influence of ingredient composition, inclusion levels and processing techniques, alongside challenges such as regulatory constraints, ingredient cost and palatability. The alignment of these alternative feeds with circular economy principles and sustainability goals further emphasizes their role in reducing environmental impact. By summarising recent advancements, this paper underscores the transformative potential of novel feed ingredients in advancing monogastric meat production towards greater nutritional quality, sustainability and consumer acceptance. Full article
25 pages, 1869 KiB  
Review
Envisioning Human–Machine Relationship Towards Mining of the Future: An Overview
by Peter Kolapo, Nafiu Olanrewaju Ogunsola, Kayode Komolafe and Dare Daniel Omole
Mining 2025, 5(1), 5; https://doi.org/10.3390/mining5010005 - 6 Jan 2025
Viewed by 221
Abstract
Automation is increasingly gaining attention as the global industry moves toward intelligent, unmanned approaches to perform hazardous tasks. Although the integration of autonomous technologies has revolutionized various industries for decades, the mining sector has only recently started to harness the potential of autonomous [...] Read more.
Automation is increasingly gaining attention as the global industry moves toward intelligent, unmanned approaches to perform hazardous tasks. Although the integration of autonomous technologies has revolutionized various industries for decades, the mining sector has only recently started to harness the potential of autonomous technology. Lately, the mining industry has been transforming by implementing automated systems to shape the future of mining and minimize human involvement in the process. Automated systems such as robotics, artificial intelligence (AI), the Industrial Internet of Things (IIOT), and data analytics have contributed immensely towards ensuring improved productivity and safety and promoting sustainable mineral industry. Despite the substantial benefits and promising potential of automation in the mining sector, its adoption faces challenges due to concerns about human–machine interaction. This paper extensively reviews the current trends, attempts, and trials in converting traditional mining machines to automated systems with no or less human involvement. It also delves into the application of AI in mining operations from the exploration phase to the processing stage. To advance the knowledge base in this domain, the study describes the method used to develop the human–machine interface (HMI) that controls and monitors the activity of a six-degrees-of-freedom robotic arm, a roof bolter machine, and the status of the automated machine. The notable findings in this study draw attention to the critical roles of humans in automated mining operations. This study shows that human operators are still relevant and must control, operate, and maintain these innovative technologies in mining operations. Thus, establishing an effective interaction between human operators and machines can promote the acceptability and implementation of autonomous technologies in mineral extraction processes. Full article
(This article belongs to the Special Issue Envisioning the Future of Mining, 2nd Edition)
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<p>Autonomous drilling rig connected to GNSS for real time positioning, navigation, and timing functions.</p>
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<p>Laboratory testing of an ABB robot grabbing a roof bolt for installation (adapted from Kolapo [<a href="#B79-mining-05-00005" class="html-bibr">79</a>]).</p>
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<p>The human–machine interface to autonomous roof bolter (adapted from Kolapo [<a href="#B79-mining-05-00005" class="html-bibr">79</a>]).</p>
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<p>The developed HMI for an autonomous bolting process.</p>
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<p>Global mining projects by commodity (adapted from Govreau [<a href="#B96-mining-05-00005" class="html-bibr">96</a>]).</p>
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26 pages, 2423 KiB  
Systematic Review
Social Acceptability of Critical and Strategic Minerals (CSMs) Development: A Systematic Review with a Particular Focus on Quebec, Canada
by Kossivi Fabrice Dossa, Fifanou G. Vodouhe and Damase P. Khasa
Mining 2025, 5(1), 4; https://doi.org/10.3390/mining5010004 - 6 Jan 2025
Viewed by 220
Abstract
The social acceptability (SA) of mining projects is a crucial issue for the sustainable development of territories and local communities. This article aims to identify the issues and examine the factors influencing the SA of exploration, exploitation and processing projects of critical and [...] Read more.
The social acceptability (SA) of mining projects is a crucial issue for the sustainable development of territories and local communities. This article aims to identify the issues and examine the factors influencing the SA of exploration, exploitation and processing projects of critical and strategic minerals (CSMs) in Quebec. A systematic review guided by the PRISMA approach was conducted, selecting 57 relevant documents after excluding several others. The results reveal that between 2000 and 2024, the publication of studies on SA in the mining sector has increased significantly, particularly since 2013. Research is mainly concentrated in North America, with a predominance of case studies. Their critical analysis indicates that the SA of mining projects is based on various issues, including the need for greater consideration of the perspectives of local communities, as well as open and inclusive communication between all stakeholders. However, SA is affected by various factors, including demographic, economic, environmental and governance, which can have positive or negative effects depending on the context. Following this analysis, future research should explore the complex interactions between these factors, determining how some may act as mediators or moderators in various contexts through real case studies. Full article
(This article belongs to the Special Issue Feature Papers in Sustainable Mining Engineering 2024)
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<p>Mining policy landscape supporting SA requirements. LMS = Mining Act; CEAA = Canadian Environmental Assessment Act; REMM = Metal Mining Effluent Regulations; LSMT = Mining, Oil and Gas Industries Transparency Measures Act.</p>
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<p>PRISMA flowchart describing the document selection process.</p>
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<p>Years of publication of selected documents.</p>
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<p>Diversity of journals publishing articles on social acceptability.</p>
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<p>Types of studies that have been conducted.</p>
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<p>Countries in which the selected studies were conducted.</p>
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<p>Continents on which the selected studies were conducted.</p>
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<p>Proposed framework for the continued study of factors promoting the social acceptability of mining projects. <span class="html-italic">Solid arrows indicate existing correlational research. Dotted arrows indicate where future research is needed</span>.</p>
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13 pages, 1868 KiB  
Article
Evaluation of Sericin/Polyvinyl Alcohol Mixtures for Developing Porous and Stable Structures
by Maria C. Arango, Leander Vásquez Vásquez, Akemy Carolina Homma Parra, Santiago Rueda-Mira, Natalia Jaramillo-Quiceno, Josep Pasqual Cerisuelo, Amparo Cháfer and Catalina Álvarez-López
Biomimetics 2025, 10(1), 27; https://doi.org/10.3390/biomimetics10010027 - 5 Jan 2025
Viewed by 272
Abstract
Fibrous by-products, including defective or double cocoons, are obtained during silk processing. These cocoons primarily contain fibroin and sericin (SS) proteins along with minor amounts of wax and mineral salts. In conventional textile processes, SS is removed in the production of smooth, lustrous [...] Read more.
Fibrous by-products, including defective or double cocoons, are obtained during silk processing. These cocoons primarily contain fibroin and sericin (SS) proteins along with minor amounts of wax and mineral salts. In conventional textile processes, SS is removed in the production of smooth, lustrous silk threads, and is typically discarded. However, SS has garnered attention for its antioxidant, antibacterial, biocompatible, and anticancer properties as well as its excellent moisture absorption, making it a promising polymer for biomedical applications. Owing to its functional groups (carboxyl, amino, and hydroxyl), SS can blend and crosslink with other polymers, thereby improving the mechanical properties of sericin-based materials. This study explored the effects of different SS/polyvinyl alcohol (PVA) ratios on porous scaffolds fabricated via freeze-drying, focusing on the mechanical stability, water absorption, and protein release in phosphate-buffered saline (PBS). The scaffold morphology revealed reduced porosity with higher SS content, while increased PVA content led to material folding and layering. A greater PVA content enhanced water absorption, mechanical properties, and thermal stability, although SS release decreased. These results demonstrate that scaffold properties can be tailored by optimizing the SS/PVA ratio to suit specific biomedical applications. Full article
(This article belongs to the Special Issue Bioinspired Materials for Tissue Engineering)
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<p>FTIR spectra for (a) pristine PVA, (b) SS/PVA 25/75, (c) SS/PVA 50/50, (d) SS/PVA 75/25, and (e) pristine SS scaffolds.</p>
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<p>(<b>a</b>) TGA and (<b>b</b>) DTG curves of pristine SS, PVA, and SS/PVA scaffolds at different proportions of SS/PVA (25/75, 50/50, and 75/25).</p>
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<p>SEM analysis of the cross-sectional images revealing the morphological characteristics of the SS, PVA, and SS/PVA scaffold structures.</p>
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<p>Water absorption after 24 h of immersion in water and mass loss after drying for pristine SS, PVA, and SS/PVA scaffolds at different proportions. Bars represent the standard deviation (<span class="html-italic">n</span> = 3).</p>
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<p>(<b>a</b>) Sericin release from SS/PVA scaffolds in PBS and (<b>b</b>) percentage of protein released relative to the initial sericin content in SS/PVA scaffolds.</p>
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<p>Mechanical integrity of the pristine SS, pristine PVA, and SS/PVA scaffolds in different proportions. (<b>a</b>) Full curve and (<b>b</b>) magnified initial region.</p>
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15 pages, 744 KiB  
Article
The Effect of Corn Ensiling Methods on Digestibility and Biogas Yield
by Karol Kupryaniuk, Kamil Witaszek, Iryna Vaskina, Sebastian Filipek-Kaźmierczak, Jakub Kupryaniuk, Piotr Sołowiej and Jacek Dach
Energies 2025, 18(1), 188; https://doi.org/10.3390/en18010188 - 4 Jan 2025
Viewed by 198
Abstract
This study investigates the impact of different corn silage preparation methods, namely the traditional and Shredlage methods, on digestibility and biogas yield in anaerobic digestion and its nutritional value—the first complex study of its kind. Key parameters of both silage types were analyzed, [...] Read more.
This study investigates the impact of different corn silage preparation methods, namely the traditional and Shredlage methods, on digestibility and biogas yield in anaerobic digestion and its nutritional value—the first complex study of its kind. Key parameters of both silage types were analyzed, including chemical composition, fiber content, and elemental makeup. Methane and biogas production were assessed under standardized fermentation conditions. The results showed that the Shredlage method, characterized by more intensive chopping, led to higher biogas and methane yields per unit of organic dry matter compared to traditional silage. This improvement is attributed to enhanced digestibility due to the lower content of neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude fiber in Shredlage. An elemental analysis revealed slight differences in carbon-to-nitrogen (C/N) ratios, with both silages showing values suitable for efficient fermentation. Despite minor variations in mineral content, Shredlage demonstrated greater efficiency in biogas production, particularly for rapid fermentation processes. The findings underscore the importance of silage preparation techniques in optimizing biogas yield and suggest Shredlage as a superior option for enhancing energy recovery in biogas plants. Future work should explore the economic trade-offs and scalability of these methods. Full article
(This article belongs to the Special Issue New Challenges in Biogas Production from Organic Waste)
18 pages, 6011 KiB  
Review
Application of Porous Materials in Photocatalytic Treatment of Wastewater
by Jian Nan, Xinyu Liu, Di Zhang, Rui Xu and Yong Zhang
Colloids Interfaces 2025, 9(1), 3; https://doi.org/10.3390/colloids9010003 - 3 Jan 2025
Viewed by 310
Abstract
With the increasing environmental water pollution, there is an increasing demand for efficient and sustainable wastewater treatment technologies. Photocatalysis, as an environmentally friendly oxidation technology, shows significant promise for the degradation and mineralization of organic pollutants in wastewater. Porous structured materials have received [...] Read more.
With the increasing environmental water pollution, there is an increasing demand for efficient and sustainable wastewater treatment technologies. Photocatalysis, as an environmentally friendly oxidation technology, shows significant promise for the degradation and mineralization of organic pollutants in wastewater. Porous structured materials have received much attention from scientists for the photocatalytic treatment of wastewater due to their good dispersibility and high specific surface area. Based on the exploration of the recent research papers about various porous materials in photocatalytic degradation of wastewater, we summarize the synthesis of porous materials and methods of loading catalysts, explore the applications for treating different types of pollutants, and finally present the challenges and prospects of porous materials in photocatalytic wastewater treatment. We hope that this review will inspire more researchers to focus on this important field. Full article
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<p>Substrate classification of porous materials.</p>
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<p>(<b>a</b>–<b>c</b>) Top view, side view, and 0.2 BWO/TNTAs of the SEM images of TNTAs, respectively; (<b>d</b>–<b>g</b>) EDS spectra of the corresponding Ti, O, W, and Bi [<a href="#B29-colloids-09-00003" class="html-bibr">29</a>].</p>
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<p>SEM of (<b>a</b>) mag-MIL-101(Cr); (<b>b</b>) TiO<sub>2</sub>/mag-MIL-101(Cr); (<b>c</b>,<b>d</b>) TEM of TiO<sub>2</sub>/mag-MIL-101(Cr) [<a href="#B46-colloids-09-00003" class="html-bibr">46</a>].</p>
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<p>One-step facile fabrication strategy for mixed-valence bimetallic Ce/Zr MOFs [<a href="#B70-colloids-09-00003" class="html-bibr">70</a>].</p>
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<p>Schematic of the experimental setup for the synthesis of ZnO NSs and SEM images obtained [<a href="#B76-colloids-09-00003" class="html-bibr">76</a>].</p>
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<p>Schematic diagram of experimental synthesis of porous TiO<sub>2</sub>/Ag composites [<a href="#B82-colloids-09-00003" class="html-bibr">82</a>].</p>
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<p>SEM images of ZnO nanorods doped with different concentrations of copper (<b>a</b>,<b>b</b>) ZnO nanorods doped with 5 mg and 10 mg of copper; (<b>c</b>,<b>d</b>) SEM images of ZnO nanorods doped with 15 mg and 20 mg of copper [<a href="#B104-colloids-09-00003" class="html-bibr">104</a>].</p>
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19 pages, 5354 KiB  
Article
Geophysical Characteristics of Low-Sulfide Epithermal Gold Mineralized Bodies—A Case Study of the Alinghe Mining Area on the South Bank of the Heilong River in China
by Qichun Yin, Kang Wang, Guili Tan, Yuan Ji, Huaben Yang, Haijiang Chen, Yanhai Sun, Qin Liu and Tong Sun
Minerals 2025, 15(1), 47; https://doi.org/10.3390/min15010047 - 1 Jan 2025
Viewed by 498
Abstract
The inability of geophysical methods to directly detect gold ore bodies remains a hot topic in the realm of gold geophysical exploration. Through the analysis of high-precision magnetic method, resistivity and induced polarization methods with the gradient arrays, electrical resistivity tomography, and well [...] Read more.
The inability of geophysical methods to directly detect gold ore bodies remains a hot topic in the realm of gold geophysical exploration. Through the analysis of high-precision magnetic method, resistivity and induced polarization methods with the gradient arrays, electrical resistivity tomography, and well logging, combined with the discovery of gold mineralization in exploration trenches and boreholes, it has been found that gold mineralization can be classified into two types: terminal and channel. The terminal-type gold mineralization is marked by a buried depth of less than 30 m, accompanied by varying degrees of silicification and pyritization. In contrast, the channel-type of gold mineralization is buried deeper than 30 m and occurs within structural fractures or volcanic breccia mineralized alteration zones. The resistivity difference constitutes a significant geophysical indicator differentiating these two types of gold mineralization. Both types of gold mineralization are located adjacent to IP anomalies, potentially suggesting characteristics of low-sulfur gold mineralization. After comparing several globally typical epithermal gold deposits, we conclude that the findings presented in this paper encapsulate the geophysical traits of an un-eroded, low-sulfidation epithermal gold deposit. These insights offer a valuable reference for the direct detection of similar gold orebodies using geophysical methods. Full article
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<p>(<b>a</b>) The structural location map of Alinghe Mining Area (according to Pan et al., 2009 [<a href="#B27-minerals-15-00047" class="html-bibr">27</a>]) and (<b>b</b>) the geological map. 1: Nen River-Balihan fault; 2: northwest boundary fault of Songnen basin; 3: Yilan-Yitong fault; EB: Erguna block; XB: Xing’an Block; SXB: Songnen-Xilinhot block; XXS: Xinlin-Xigutu suture zone; HHS: Hegan Mountain-Heihe suture zone.</p>
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<p>Sketch map for the gradient arrays used in RIP measurements.</p>
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<p>Map of magnetic field ΔT contour and geological boundary in the study area (see <a href="#minerals-15-00047-f001" class="html-fig">Figure 1</a> for location and names of rocks).</p>
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<p>Contour plots of apparent resistivity (<b>a</b>) and apparent amplitude frequency rate (equivalent to apparent polarizability) (<b>b</b>) in the RI-1 region and apparent resistivity (<b>c</b>) and apparent amplitude frequency rate (<b>d</b>) in the RI-2 region in the study area (see <a href="#minerals-15-00047-f001" class="html-fig">Figure 1</a> for location of RI-1 and RI-2).</p>
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<p>Gold-bearing silicified andesite revealed in ET-1.</p>
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<p>Inversion and interpretation profiles of ERT-1 (<b>a</b>) resistivity, (<b>b</b>) chargeability and ERT-2, (<b>c</b>) resistivity, and (<b>d</b>) chargeability (see <a href="#minerals-15-00047-f001" class="html-fig">Figure 1</a> for location).</p>
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<p>Main logging curves and results of the borehole BH-1 (the colors in lithology column correspond to the descriptions provided in <a href="#sec4dot5dot1-minerals-15-00047" class="html-sec">Section 4.5.1</a>.).</p>
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<p>Crossplot of geophysical parameters of andesitic surrounding rock (<b>a</b>), andesitic volcanic breccia (<b>b</b>), gold mineralized bodies, and other meaningful logging sections (<b>c</b>) of the borehole BH-1.</p>
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14 pages, 2183 KiB  
Article
Small Extracellular Vesicles Derived from Lipopolysaccharide-Treated Stem Cells from the Apical Papilla Modulate Macrophage Phenotypes and Inflammatory Interactions in Pulpal and Periodontal Tissues
by Solène Tessier, Boris Halgand, Davy Aubeux, Joëlle Véziers, Angélique Galvani, Juliette Jamoneau, Fabienne Pérez, Valérie Geoffroy and Alexis Gaudin
Int. J. Mol. Sci. 2025, 26(1), 297; https://doi.org/10.3390/ijms26010297 - 31 Dec 2024
Viewed by 271
Abstract
Inflammation significantly influences cellular communication in the oral environment, impacting tissue repair and regeneration. This study explores the role of small extracellular vesicles (sEVs) derived from lipopolysaccharide (LPS)-treated stem cells from the apical papilla (SCAP) in modulating macrophage polarization and osteoblast differentiation. SCAPs [...] Read more.
Inflammation significantly influences cellular communication in the oral environment, impacting tissue repair and regeneration. This study explores the role of small extracellular vesicles (sEVs) derived from lipopolysaccharide (LPS)-treated stem cells from the apical papilla (SCAP) in modulating macrophage polarization and osteoblast differentiation. SCAPs were treated with LPS for 24 h, and sEVs from untreated (SCAP-sEVs) and LPS-treated SCAP (LPS-SCAP-sEVs) were isolated via ultracentrifugation and characterized using transmission electron microscopy, Western blot, and Tunable Resistive Pulse Sensing. LPS-SCAP-sEVs exhibited characteristic exosome morphology (~100 nm diameter) and expressed vesicular markers (CD9, CD63, CD81, and HSP70). Functional analysis revealed that LPS-SCAP-sEVs promoted M1 macrophage polarization, as evidenced by the increased pro-inflammatory cytokines (IL-6 and IL-1β) and the reduced anti-inflammatory markers (IL-10 and CD206), while impairing the M2 phenotype. Additionally, LPS-SCAP-sEVs had a minimal impact on SCAP metabolic activity or osteogenic gene expression but significantly reduced mineralization capacity in osteogenic conditions. These findings suggest that sEVs mediate the inflammatory interplay between SCAP and macrophages, skewing macrophage polarization toward a pro-inflammatory state and hindering osteoblast differentiation. Understanding this sEV-driven communication axis provides novel insights into the cellular mechanisms underlying inflammation in oral tissues and highlights potential therapeutic targets for modulating extracellular vesicle activity during acute inflammatory episodes. Full article
(This article belongs to the Special Issue Molecular Advances in Dental Pulp Tissue Engineering, 2nd Edition)
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<p>Characterization of sEVs derived from control SCAP (sEVs-CT) (<b>a</b>) or from LPS-treated SCAP (sEVs-LPS) (<b>b</b>). Size distribution and concentration of sEVs-CT (<b>a</b>) and sEVs-LPS (<b>b</b>) assessed using Tunable Resistive Pulse Sensing (TRPS) technology. (<b>c</b>) TRPS analysis showing the mean size of sEVs-CT and sEVs-LPS. (<b>d</b>) TRPS analysis showing the quantity of sEVs-CT and sEVs-LPS secreted per cell. (<b>e</b>) Ultrastructure of sEVs-CT and sEVs-LPS observed using electron microscopy. (<b>f</b>) Protein concentrations of sEVs-CT and sEVs-LPS determined by micro-BCA assay. (<b>g</b>) Expression of sEV-associated protein positive markers (HSP70, CD63, CD9, and CD81). GM130, a cis-Golgi matrix protein, was used as a negative control to confirm the absence of Golgi apparatus contamination by Western blot. Data are expressed as mean ± SEM. <span class="html-italic">N</span> = 3. * <span class="html-italic">p</span> &lt; 0.05 (Student’s <span class="html-italic">t</span>-test).</p>
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<p>Effect of sEVs-CT and sEVs-LPS on SCAP osteoblastic differentiation and mineralization capacity. (<b>a</b>–<b>c</b>) Expression of representative genes of osteoblastic differentiation, including <span class="html-italic">ALP</span> (<b>a</b>)<span class="html-italic">, Col1a1</span> (<b>b</b>), and <span class="html-italic">Runx2</span> (<b>c</b>), determined by RT-qPCR. Gene expression (2<sup>−ΔΔ</sup> CT) was normalized to SCAP at day 0 and presented as fold change. In total, <span class="html-italic">18S</span> and <span class="html-italic">PPIA</span> were used as housekeeping genes. (<b>d</b>) Alizarin Red S staining performed on SCAP cultured in an osteogenic induction medium for 17 days. The effects of untreated and LPS-treated SCAP conditioned medium were compared. (CT +: positive control (osteogenic medium); CT −: negative control (the osteogenic medium with exosome-depleted fetal bovine serum); CT-CM: Conditioned medium; LPS-CM: Conditioned medium with LPS). (<b>e</b>) Quantification of the degree of mineralization assessed by dissolution of mineralization crystals with methanol and acetic acid. The optical density was measured at 450 nm. (<b>f</b>) Effect of 1X (1 × 10<sup>7</sup> sEVs per well) and 5X (5 × 10<sup>7</sup> sEVs per well) of sEVs-CT and sEVs-LPS on SCAP metabolic activity determined by CCK-8 assay. The results are presented as the percentage of metabolic activity relative to untreated SCAP at day 0. The data are expressed as mean ± SEM from three independent experiments (<span class="html-italic">N</span> = 3), each performed in triplicate (<span class="html-italic">n</span> = 3). <span class="html-italic">p</span>-values derived from one-way ANOVA followed by Tukey’s multiple comparison tests is * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>Effect of sEVs-LPS on polarized macrophages. Expression of representative pro-inflammatory marker genes including <span class="html-italic">IL-6</span> (<b>a</b>), <span class="html-italic">TNF-α</span> (<b>b</b>), and <span class="html-italic">IL-1β</span> (<b>c</b>); and anti-inflammatory marker genes, <span class="html-italic">IL-10</span> (<b>d</b>) and <span class="html-italic">CD206</span> (<b>e</b>), after treatment of polarized macrophages with sEVs derived from SCAP or LPS-induced SCAP for 24 h determined by RTqPCR. Gene expression (2<sup>−ΔΔ</sup> CT) was normalized to untreated M0 macrophages and presented as fold change. The <span class="html-italic">18S</span> and <span class="html-italic">PPIA</span> were used as housekeeping genes. Quantification of pro-inflammatory factors IL-6 (<b>f</b>), TNF-α (<b>g</b>), and IL-1β (<b>h</b>) in the culture supernatant of M0 macrophages using bead-based multiplex assays by flow cytometry. The data are expressed as mean ± SEM. <span class="html-italic">N</span> = 3; <span class="html-italic">n</span> = 3. <span class="html-italic">p</span>-values derived from one-way ANOVA followed by Tukey’s multiple comparison tests are * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, and **** <span class="html-italic">p</span> &lt; 0.0001.</p>
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14 pages, 3714 KiB  
Article
Experimental Validation of Antiobesogenic and Osteoprotective Efficacy of Ginsenoside CK via Targeting Lipid and Atherosclerosis Pathways
by Md. Niaj Morshed, Reshmi Akter, Imran Mahmud, Ah-Yeong Gwon, Jin Woo Jeang, Yeong-Geun Lee, Dae Won Park, Deok Chun Yang, Yeon Ju Kim and Se-Chan Kang
Life 2025, 15(1), 41; https://doi.org/10.3390/life15010041 - 31 Dec 2024
Viewed by 353
Abstract
The present study explored the possible antiobesogenic and osteoprotective properties of the gut metabolite ginsenoside CK to clarify its influence on lipid and atherosclerosis pathways, thereby validating previously published hypotheses. These hypotheses were validated by harvesting and cultivating 3T3-L1 and MC3T3-E1 in adipogenic [...] Read more.
The present study explored the possible antiobesogenic and osteoprotective properties of the gut metabolite ginsenoside CK to clarify its influence on lipid and atherosclerosis pathways, thereby validating previously published hypotheses. These hypotheses were validated by harvesting and cultivating 3T3-L1 and MC3T3-E1 in adipogenic and osteogenic media with varying concentrations of CK. We assessed the differentiation of adipocytes and osteoblasts in these cell lines by applying the most effective doses of CK that we initially selected. Using 3T3-L1 adipocytes in vitro assessments, CK could effectively decrease intracellular lipid accumulation, inhibit α-glucosidase enzyme, increase 2-NBDG glucose uptake, reduce inflammation-associated cytokines (TNFα, and IL-6), adipogenic regulatory genes (PPARγ, FAS, C/EBPα), lipogenic gene LPL, and increase the expression of thermogenic gene UCP1. Additionally, CK treatment induced osteoblast development in MC3T3-E1 cells as shown by increased mineralization and calcium distribution, collagen content, alkaline phosphatase activity, and decreased inflammatory cytokines TNFα, and IL-6 and increased the regulated expressions of osteogenic genes including Runx2, ALP, BGLAP, OCN, and Col1a1. Significantly, as a major inhibitory regulator, the TP53 gene was down-regulated in both 3T3-L1 and MC3T3E1 cells after the treatment of CK. These encouraging results demonstrate the possible use of CK as an innovative treatment for controlling obesity and osteoporosis, targeting the underlying mechanisms of obesogenic and bone loss. Further studies are necessary to explore the clinical implications of these results and the potential of CK in future treatment strategies. This research highlights the promise of CK in addressing significant health issues. Full article
(This article belongs to the Section Pharmaceutical Science)
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<p>The MTT assay was used to measure cell viability. CK (3.125–50 μM) was administered to (<b>A</b>) 3T3-L1 pre-adipocyte (Orange-colored columns) and (<b>B</b>) MC3T3-E1 pre-osteoblast cells (1 × 10<sup>4</sup> cells/well) (Tan-colored columns) for 24 h. A two-tailed Student’s <span class="html-italic">t</span>-test was used to determine whether there was a substantial distinction between the groups; ns denotes a non-significant change, * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01 when compared to a control group (Black-colored column) that was not treated.</p>
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<p>The inhibitory effect of CK on lipid accumulation in MDI-induced 3T3-L1 adipocytes was assessed as follows: (<b>A</b>) Oil Red O staining was performed to visualize fat droplets, which were then observed under a light microscope at 20× magnification. (<b>B</b>) Lipid accumulation was quantified by measuring the absorbance of Oil Red O dissolved in isopropyl alcohol at 520 nm. Data represent the mean ± SEM from three independent experiments. Statistical significance is indicated as ### <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001, compared to the MDI-treated group.</p>
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<p>(<b>A</b>) The proportion of a-glucosidase inhibition at various CK concentrations. Acarbose, or ACR, was employed as a control. We also analyzed the half-maximum inhibitory concentration (IC<sub>50</sub>) of CK and ACR (<b>B</b>) 3T3L1 cells using the 2-NBDG uptake test. Using a fluorescent derivative of glucose 2-NBDG, the impact of CK on 3T3L1 cells’ glucose absorption was examined for 24 h with and without CK. Insulin was employed as a positive control at 100 nM. Data are presented as a control percentage. *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>The relative expression of inflammatory genes (<span class="html-italic">TNFα</span>, <span class="html-italic">IL-6</span>), adipogenic genes (<span class="html-italic">PPARγ</span>, <span class="html-italic">C/EBPα</span>, <span class="html-italic">LPL</span>), the lipogenic gene <span class="html-italic">FAS</span>, and the thermogenic gene <span class="html-italic">UCP1</span>, along with <span class="html-italic">TP</span><sup>53</sup>, was measured in differentiated 3T3-L1 cells treated with CK at concentrations of 2.5 μM and 10 μM, or RSG at 20 μM. Results are presented as the mean ± standard deviation from three independent experiments. Statistical significance was assessed using a two-tailed Student’s <span class="html-italic">t</span>-test. Significant differences in gene expression between untreated and treated groups are indicated as ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>(<b>A</b>) ALP activity in CK and E<sub>2</sub>-treated differentiated MC3T3-E1 cells. (<b>B</b>) The impact of CK on MC3T3-E1 cell mineralization. A 96-well plate was used to measure the quantity of Alizarin Red S at 562 nm. (<b>C</b>) The calcium-binding Alizarin Red S dye was used to evaluate the calcium deposits in the extracellular matrix for matrix mineralization. Up to Day 28, CK treatment accelerated the mineralization of the extracellular matrix. The images are representative of over three different concentrations of CK and E<sub>2.</sub> The results are presented as the mean ± standard deviation from three independent experiments. Statistical significance was determined using a two-tailed Student’s <span class="html-italic">t</span>-test. Significant differences in lipid production compared to the untreated (control) group are denoted by ** <span class="html-italic">p</span> &lt; 0.01, and *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Collagen content in MC3T3-E1 cells is increased by CK extracts. For 12 days, cells were exposed to extracts at doses ranging from 2.5 to 10 μM, either with or without a differentiation medium. E<sub>2</sub> was used at a concentration of 100 nm. (<b>A</b>) Picro-Sirius red staining was carried out and seen using a microscope (magnification of ×100). (<b>B</b>) Absorbance was measured at 550 nm to determine the amount of collagen. The presented data are the mean ± standard deviation (SD) of three studies. Statistical analysis revealed significant differences, denoted as * <span class="html-italic">p</span> &lt; 0.1, *** <span class="html-italic">p</span> &lt; 0.001 when compared with the indicated ascorbic acid and β-glycerophosphate treated group.</p>
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<p>Relative expression of proinflammatory cytokines TNFα, and IL-6, and osteogenic genes <span class="html-italic">RunX2</span>, <span class="html-italic">ALP</span>, <span class="html-italic">BGLAP</span>, <span class="html-italic">OCN</span>, and <span class="html-italic">COL1a1</span> with <span class="html-italic">TP</span><sup>53</sup> in differentiated MC3T3-E1 cells on treatment with CK at 2.5 μM and E<sub>2</sub> at 100 nm concentrations, respectively. A two-tailed Student’s <span class="html-italic">t</span>-test was used to determine whether the difference was statistically significant. The non-treated and treated groups’ significant differences in gene expression are indicated by * <span class="html-italic">p</span> &lt; 0.1, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.001 vs. control.</p>
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39 pages, 71974 KiB  
Article
Geology, Petrology and Geochronology of the Late Cretaceous Klaza Epithermal Deposit: A Window into the Petrogenesis of an Emerging Porphyry Belt in the Dawson Range, Yukon, Canada
by Well-Shen Lee, Daniel J. Kontak, Patrick J. Sack, James L. Crowley and Robert A. Creaser
Minerals 2025, 15(1), 38; https://doi.org/10.3390/min15010038 - 31 Dec 2024
Viewed by 488
Abstract
Geologic understanding of the richly mineralized Dawson Range gold belt (DRGB) in the central Yukon, Canada is hindered by: (1) limited outcrop exposure due to thick soil cover; and (2) low resolution age-constraints despite a long history of porphyry Cu–Au–Mo deposit (PCD) exploration. [...] Read more.
Geologic understanding of the richly mineralized Dawson Range gold belt (DRGB) in the central Yukon, Canada is hindered by: (1) limited outcrop exposure due to thick soil cover; and (2) low resolution age-constraints despite a long history of porphyry Cu–Au–Mo deposit (PCD) exploration. Here, the well-preserved Klaza Au–Ag–Pb–Zn porphyry–epithermal deposit is used as a type-example of Late Cretaceous magmatic–hydrothermal mineralization to address the complex metallogeny of the DRGB. U–Pb zircon dating defines four magmatic pulses of Late Triassic to Late Cretaceous ages with the latter consisting of the Casino (80–72 Ma) and Prospector Mt. (72–65 Ma) suites. The Casino suite has five phases of intermediate-to-felsic calc-alkaline composition, correspond with older (77 Ma) porphyry mineralization, and displays evidence of magma mingling. The intermediate-to-mafic, slightly alkalic Prospector Mt. suite shows evidence of mingling with the youngest Casino suite phases, correlates with younger (71 Ma), intermediate-sulfidation epithermal and porphyry-type mineralization, and shoshonitic basalts of the Carmacks Group. Zircon trace element data suggest a common melt source for these suites; however, the younger suite records features (e.g., high La/Yb) that indicate a higher pressure melt source. The results from this study highlight the Prospector Mt. suite as a historically overlooked causative magma event linked to Au-rich PCDs in the DRGB and extends the temporal window of PCD prospectivity in this area. The transition from mid-Cretaceous Whitehorse suite magmas to Late Cretaceous Casino-Prospector Mt. suite magmas is proposed to reflect a transition from subduction to localized extension, which is becoming more recognized as a common characteristic of productive porphyry belts globally. Full article
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Figure 1

Figure 1
<p>Regional- and local-scale geological maps of the study area. (<b>A</b>) Inset map showing the location of the Klaza deposit and the Dawson Range Gold Belt relative to cities in the Yukon. (<b>B</b>) Simplified geologic map of the southern Dawson Range redrawn and modified from Yukon Geological Survey [<a href="#B35-minerals-15-00038" class="html-bibr">35</a>]. The locations of the Mt. Nansen Gold Corridor (MNGC) and Freegold Mt. District (FGMD) are indicated. All mineral occurrences displayed in this map are either porphyry or epithermal systems. (<b>C</b>) Geologic map of the Mt. Nansen Gold Corridor modified from Sack et al. [<a href="#B36-minerals-15-00038" class="html-bibr">36</a>] and Lee et al. [<a href="#B37-minerals-15-00038" class="html-bibr">37</a>]. The locations of the Klaza deposit and past-producing Brown-McDade mine are indicated. A cross-section of (<b>A</b>,<b>A′</b>) matching the colour scheme of this map is provided. UTM Zone 08, Datum: NAD 83.</p>
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<p>Polished (<b>left</b>) and stained (<b>right</b>; sodium cobaltinitrite) samples of important igneous rocks at Klaza. Note the unit name is provided on the left side of images. (<b>A</b>) Minto suite granodiorite with subhedral K-feldspar phenocrysts (surface sample). (<b>B</b>) Mt. Nansen Group andesite from adjacent to deposit area (surface sample). (<b>C</b>) Whitehorse suite (WS) hornblende-biotite granodiorite having a light propylitic overprint (Eastern BRX zone: KL-17-374; 75 m). (<b>D</b>) WS biotite-hornblende tonalite (KL-15-286; 93 m). (<b>E</b>) Casino suite (CS) monzogranite to granite (Kelly zone: KL-16-314; 117 m). (<b>F</b>) CS plagioclase(-biotite) phyric diorite (i3a phase). (<b>G</b>) CS hornblende diorite (Kelly zone: KL-16-314; 331 m). (<b>H</b>) CS plagioclase-quartz-biotite phyric granodiorite (Kelly zone: KL-16-314; 358 m). (<b>I</b>) Plagioclase-quartz(-biotite) phyric granodiorite (Kelly zone: KL-16-314; 453 m). (<b>J</b>) Prospector Mt. suite plagioclase phyric biotite diorite (Kl-14-193; 248 m). (<b>K</b>) Carmacks Group basalt (surface sample). (<b>L</b>) Timeline with crosscutting relationships among various intrusive phases and high- to low-temperature vein types at the Klaza deposit and Kelly prospect. Mineral abbreviations in accordance with Whitney and Evans [<a href="#B40-minerals-15-00038" class="html-bibr">40</a>].</p>
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<p>Images of drill core and polished thin sections (pts) in crossed nicols of various units in the Klaza deposit setting. (<b>A</b>) Gradational contact between i3a and i3b phases (Kelly zone: KL-16-314; 358.2 m depth). (<b>B</b>) Clast of i3a phase within i3b (Kelly zone: KL-16-314; 370.2 m depth). (<b>C</b>) Dike of i3a cutting i3b phase (Kelly zone: KL-16-314; 352.65 m depth). (<b>D</b>) Clast of i3b phase in the i3c phase (Kelly zone: KL-16-314; 358.8 m depth). (<b>E</b>) Pts image of embayed quartz grains in i4 phase dike. Note that the matrix is mostly sericite and biotite (surface sample). (<b>F</b>) Pts image of a relict sieve-textured plagioclase grain in a sericite-altered groundmass in i4 phase dike (Kelly zone: KL-16-314; 446.5 m). (<b>G</b>) Pts image of sieve-textured plagioclase grain intergrown with biotite and hornblende in i3b phase (Kelly zone: KL-16-314; 332.2m). (<b>H</b>) EDM-type vein overprinted by propylitic alteration with later fractures lined by pyrite and chalcopyrite (Kelly zone: KL-16-314; 442.3 m depth). (<b>I</b>) EDM-type vein cored by an A-type vein (Kelly zone: KL-16-314; 358 m depth). (<b>J</b>) A-type vein overprinted by phyllic alteration (Kelly zone: KL-16-314; 379.19 m depth). (<b>K</b>) B-type vein with pyrite overprinted by phyllic alteration (Kelly zone: KL-16-314; 114 m depth). (<b>L</b>) Quartz–molybdenite vein cut by epithermal-type pyrite and carbonate veins (Kelly zone: KL-16-314; 431 m depth). (<b>M</b>) D-type vein boarded by phyllic alteration (Central Klaza zone: KL-15-240; 146 m depth). (<b>N</b>) Tourmaline–quartz–muscovite–pyrite vein with associated phyllic alteration (Central Klaza zone: KL-12-133; 327.75 m depth). Mineral abbreviations in accordance with Whitney and Evans [<a href="#B40-minerals-15-00038" class="html-bibr">40</a>].</p>
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<p>Rock slabs and backscatter electron (BSE) images of rock type and veins at Klaza along with a schematic diagram summarizing the evolution of the setting. (<b>A</b>) Anhedral i4 dike clast within i5 dike (Kelly zone: KL-16-309; 395.66 m depth). (<b>B</b>) Stage 2b vein cutting i5 dike (Central Klaza zone: KL-11-12; 195.8 m depth). (<b>C</b>) Stage 2b and stage 3 vein at the contact between an i5 dike and i1 granodiorite (Central Klaza zone: KL-11-12; 176.5 m depth). (<b>D</b>) Prospector Mt. suite dike (i5) brecciated and cemented by Stage 2c (Western Klaza zone: KL-14-178; 96.5 m depth). (<b>E</b>) Stage 2a massive pyrite cut by Stage 2b cloudy quartz–pyrite–sphalerite–arsenopyrite vein and Stage 2c galena–sphalerite–tetrahedrite (Central BRX zone: KL-14-428; 57 m depth). (<b>F</b>) Stage 2a massive arsenopyrite and prismatic Stage 2a quartz (Western BRX zone: KL-17-398; 123 m depth). (<b>G</b>) Stage 2b banded arsenopyrite–pyrite–sphalerite–quartz vein with a centre-fill Stage 2c galena–sphalerite–tetrahedrite–quartz vein (Central Klaza zone: KL-14-193; 271.86 m depth). (<b>H</b>) Stage 3 rhodochrosite vein with sphalerite cutting Stage 2c galena–sphalerite–tetrahedrite–quartz (Western BRX zone: KL-17-398; 123.5 m depth). (<b>I</b>) BSE image of Stage 2c galena with tetrahedrite inclusions (Central Klaza zone: KL-11-12; 221.19 m). (<b>J</b>) SEM X-ray map of (<b>I</b>) showing the Ag-rich nature of tetrahedrite. (<b>K</b>) Bladed barite hosted in quartz-carbonate alongside banded ankerite veins from stage 3 (Central Klaza zone: KL-11-18; 181.90 m). (<b>L</b>) Colloform- and moss-textured quartz-carbonate vein from stage 3 (Central Klaza zone: KL-12-133; 148.65 m depth). (<b>M</b>) Fault gouge containing milled vein and wallrock material (Western BRX zone: KL-17-401; 82 m depth). (<b>N</b>) Silicified breccia in i1 granodiorite (Central Klaza zone: KL-12-133; 352.20 m depth). (<b>O</b>) A schematic diagram of the Klaza composite vein substages and their relationship to magmatic and high-T vein phases. Mineral abbreviations in accordance with Whitney and Evans [<a href="#B40-minerals-15-00038" class="html-bibr">40</a>].</p>
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<p>Summary of veins and alteration at the Klaza deposit setting. (<b>A</b>) Representative slab of unit i3b (i.e., a hornblende diorite) showing example of alteration types present in the vicinity of composite epithermal veins. (<b>B</b>) Close up view of porphyry-related propylitic (p-Pro) and epithermal vein-related propylitic (v-Pro) alteration. The boundary between these alteration types is defined by the alteration of biotite and amphibole to rutile and leucoxene. (<b>C</b>) Close up view of epithermal vein-related phyllic (v-Phy) and v-Pro alteration. (<b>D</b>) Schematic diagram depicting the transitional mineral stabilities of primary magmatic phases among the different alteration types. Mineral abbreviations in accordance with Whitney and Evans [<a href="#B40-minerals-15-00038" class="html-bibr">40</a>].</p>
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<p>Comparison of drillhole KL-12-114 (110 to 121.5 m depth) from the Klaza setting as seen in 2012 (<b>A</b>) versus in 2019 (<b>B</b>) to highlight the orange staining from the oxidation of the Fe-carbonate alteration. (<b>C</b>) Close-up view of the Fe-stained carbonate. (<b>D</b>,<b>E</b>) Comparison of carbonate colour in the same piece of core from 2012 (<b>D</b>) and 2019 (<b>E</b>).</p>
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<p>Summary of Ar–Ar age spectra for muscovite obtained from step-wise heating of pure mineral separates. Note that the grey denotes the steps used in the plateau age calculations. (<b>A</b>) KZ-1 (KL-12-133; 442 m). (<b>B</b>) KZWS17-03 (KL-15-240; 146 m). (<b>C</b>) KZWS17-56 (KL-12-133; 93 m depth).</p>
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<p>Summary of results for CA-TIMS U–Pb zircon geochronology for intrusive phases i2 (<b>A</b>), i3a (<b>B</b>), i4 (<b>C</b>), and i5 (<b>D</b>). The diagrams on the left are Concordia plots. Middle diagrams are weighted mean plots, and images on the right show pieces of representative material from the drillhole sample interval that was submitted for dating. Red ellipses in the Concordia plots and red bars in weighted mean plots denote the data for the youngest crystalizing zircons in the sample (autocrysts). The grey zone in the weighted mean plots represents the 2σ uncertainty limits whereas the green line represents the weighted mean. Images are also shown of the dated phases.</p>
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<p>Summary of results from in situ LA-ICP-MS U–Pb dating of zircon for various intrusive rocks (<b>A</b>–<b>E</b>) in the Klaza setting shown in both weighted mean plots and Concordia diagrams. Red bars in the weighted mean plots denote data used for calculating the weighted mean age constraints. The grey zone in the weighted mean plots represents the 2σ uncertainty limits whereas the green line represents the weighted mean. Images are also shown of the dated phases.</p>
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<p>Schematic diagram depicting the provenance of igneous zircon in the different magmatic phases of the Klaza setting. This diagram illustrates the complexities of the magmatic environment of the Klaza system, where the Whitehorse suite, Casino suite, and Prospector Mountain suite share a common reservoir, resulting in the inheritance issues described above. Care must be taken by the geochronologist to ensure that only autocrysts are used in constraining the crystallization age of the intrusive phase.</p>
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<p>Plots of chondrite-normalized REE values for each group of zircons showing the range in grey and averages marked by dots. The diagrams are arranged in the order of Whitehorse suite (<b>A</b>), Casino suite (<b>B</b>) and Prospector Mountain suite (<b>C</b>). Chondrite data from Sun and McDonough [<a href="#B62-minerals-15-00038" class="html-bibr">62</a>].</p>
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<p>Summary of the trace element chemistry of zircons from different phases at the Klaza setting. (<b>A</b>) Binary plot comparing Hf/Y with Th/U. (<b>B</b>) Binary plot comparing Yb/Gd with Th/U. (<b>C</b>) Binary plot comparing Yb/Gd with Sm/Ce. (<b>D</b>) Binary plot comparing Gd with Yb. (<b>E</b>) Binary plot comparing Nb/Ta with Th/U. (<b>F</b>) Binary plot comparing calculated zircon U–Pb ages with Th/U.</p>
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<p>Summary of age, inferred temperatures of formation, and geochemical data for zircons from the different phases in the Klaza study area. (<b>A</b>–<b>D</b>) Binary plots comparing the calculated temperature based on Ti in zircon to Hf (<b>A</b>), calculated age (<b>B</b>), Eu/Eu* (<b>C</b>), and Ce/Ce*C (<b>D</b>). (<b>E</b>) Binary plot comparing Eu/Eu* with Ce/Ce*C. (<b>F</b>) Binary plot comparing calculated U–Pb ages with Ce/Ce*C.</p>
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<p>Histogram and relative probability plots for the various geochronological data (U–Pb zircon and Ar–Ar muscovite) from this study.</p>
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<p>Compilation of geochronological data relevant to the Klaza study area based on this study and data from previous workers. Cited geochronological data are from Mortensen et al. [<a href="#B17-minerals-15-00038" class="html-bibr">17</a>,<a href="#B70-minerals-15-00038" class="html-bibr">70</a>], Selby and Creaser [<a href="#B33-minerals-15-00038" class="html-bibr">33</a>], Selby et al. [<a href="#B34-minerals-15-00038" class="html-bibr">34</a>], and Stevens et al. [<a href="#B71-minerals-15-00038" class="html-bibr">71</a>].</p>
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<p>(<b>A</b>) Schematic tectonic model from the Late Triassic to the mid-Cretaceous (90 Ma), based on models proposed by Monger and Gibson [<a href="#B91-minerals-15-00038" class="html-bibr">91</a>]. (<b>B</b>) Schematic tectonic model for the Late Cretaceous (80–65 Ma) supported by the model proposed by Gabrielse et al. [<a href="#B92-minerals-15-00038" class="html-bibr">92</a>]. (<b>C</b>–<b>E</b>) Schematic petrogenetic evolution of the district from the Late Triassic to the latest Cretaceous. Note the inset key in the upper right for various magmatic events.</p>
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<p>(<b>A</b>) Simplified geological map of the Dawson Range including the Sixtymile area. Only igneous rocks comprising ages discussed in this contribution are displayed. (<b>B</b>) Compilation of geochronologic data for other Late Cretaceous porphyry–epithermal occurrences in the Dawson Range Gold Belt. Regional geochronology data sourced from Allan et al. [<a href="#B1-minerals-15-00038" class="html-bibr">1</a>], Mortensen et al. [<a href="#B17-minerals-15-00038" class="html-bibr">17</a>], Mottram et al. [<a href="#B32-minerals-15-00038" class="html-bibr">32</a>], Selby and Creaser [<a href="#B33-minerals-15-00038" class="html-bibr">33</a>], Selby et al. [<a href="#B34-minerals-15-00038" class="html-bibr">34</a>], Stevens et al. [<a href="#B71-minerals-15-00038" class="html-bibr">71</a>], Bineli-Betsi et al. [<a href="#B95-minerals-15-00038" class="html-bibr">95</a>], Bineli-Betsi and Bennette [<a href="#B96-minerals-15-00038" class="html-bibr">96</a>], Friend [<a href="#B97-minerals-15-00038" class="html-bibr">97</a>], Bennett et al. [<a href="#B98-minerals-15-00038" class="html-bibr">98</a>], and Godwin [<a href="#B99-minerals-15-00038" class="html-bibr">99</a>].</p>
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15 pages, 3478 KiB  
Article
Gravity Survey for Mineral Exploration in Gerolekas Bauxite Mining Site in Greece
by Dimitrios Karaiskos, Georgios Apostolopoulos and Christos Orfanos
Mining 2025, 5(1), 3; https://doi.org/10.3390/mining5010003 - 31 Dec 2024
Viewed by 388
Abstract
This study presents a gravity survey conducted for mineral exploration in the Gerolekas overthrust area at a bauxite mining site in Central Greece. In the summer of 2018, a gravity survey, covering 28 km2, was conducted, including confirmed and unexplored zones. [...] Read more.
This study presents a gravity survey conducted for mineral exploration in the Gerolekas overthrust area at a bauxite mining site in Central Greece. In the summer of 2018, a gravity survey, covering 28 km2, was conducted, including confirmed and unexplored zones. By utilizing gravity data, we investigated the shallow subsurface geology and structural sequences, resulting in a high-resolution 3D density model. This model is generated through constrained gravity inversion by the exploitation of the boreholes available at mining sites, and the geological survey fills the areas with boreholes, which provides the stratigraphy to some depth. The suggested data-processing techniques provide information for the tectonism of the area, which is also important for mineral exploration, as well as mining design. The interface with density contrast between the flysch and the underlying limestone in the high-resolution 3D density model provides useful information on the geological status, but also, the slight density difference in limestone provides an interface where bauxite deposits can be. The inversion, conducted with EMIGMA software, incorporated high-resolution topography data and density constraints to produce a reliable 3D density model. The findings highlight the gravity method’s potential to enhance mineral exploration efficiency, offering a robust tool for further geological and mining considerations. Full article
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Figure 1
<p>Geotectonic map of Hellenides, with highlighted the Parnassus–Ghiona Zone [<a href="#B26-mining-05-00003" class="html-bibr">26</a>] (<b>a</b>), Lithostratigraphic and distribution column of bauxite deposits in the Parnassus–Gkiona Zone [<a href="#B27-mining-05-00003" class="html-bibr">27</a>] (<b>b</b>).</p>
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<p>Main steps of the proposed workflow.</p>
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<p>Geological map of the Institute of Geological and Mining (IGME, Amfissa Sheet) combined with the boreholes made by Delfi distomon S.A. (<b>a</b>). Cross-section of boreholes with total depth &gt; 300 m (<b>b</b>).</p>
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<p>The 3D lithology model of the survey area.</p>
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<p>Initial 3D density model computed in order to be used for the inversion (<b>a</b>) (UTM34N). Cross-sections of the initial 3D density model (<b>b</b>) (UTM34N).</p>
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<p>Depiction of the field data acquisition (<b>a</b>), topography map with integrated gravity stations (<b>b</b>).</p>
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<p>Bouguer gravity anomaly map (miliGals) (<b>a</b>), regional gravity anomaly map (miliGals) (<b>b</b>).</p>
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<p>Residual gravity anomaly map (miligals).</p>
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<p>Panoramic overview of the 3D density model (kg/m<sup>3</sup>).</p>
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<p>N-S density (g/cm<sup>3</sup>) sections of the 3D model between altitudes 600 m to −500 m.</p>
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<p>Comparison between the model gravity anomaly and residual gravity anomaly data. (<b>a</b>) Simulated Residual Gravity Anomaly Map vs (<b>b</b>) Measured residual gravity Anomaly Map.</p>
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<p>Tilt angle map of the area (coordinates in UTM34N).</p>
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<p>First-order derivatives chosen as suitable for pointing out the faults in the area (coordinates in UTM34N).</p>
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<p>Residual gravity anomaly map, (UTM34N) with the suggested processing fault lines along with the existing boreholes (black crosses) and the old reflection seismic profiles (red lines) (<b>a</b>), all the previous on Google Earth Map (<b>b</b>).</p>
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<p>Panoramic 3D view of the N-S density (g/cm<sup>3</sup>) sections of the 3D model between altitudes 1000 m and 500 m along with the borehole data (CL: cap Gerolekas limestone, AA, KK: loose sediments, QA: alluvial deposits, BX: bauxite, C3: “Floor” limestone, C5: “Ceiling” limestone Cretaceous, C8: Maastrichtian, FP: flysch).</p>
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17 pages, 15255 KiB  
Article
The Genesis of Cs-Rich Geyserite in the Chabu Geothermal Field in Southern Tibet
by Ruo-Ming Li, Yu-Bin Li, Chang-Jin Yang, Jin-Shu Zhang, Cong Shen, Lin Yuan, Can Yang, Guo-Miao Xu, Duo Liu, Lin-Chao Yang, Ze-Lin Zhang and Zhe-Wei Sun
Minerals 2025, 15(1), 36; https://doi.org/10.3390/min15010036 - 30 Dec 2024
Viewed by 326
Abstract
Recent studies have shown that the geothermal systems in Tibet are rich in rare metal elements such as lithium (Li), boron (B), rubidium (Rb), and cesium (Cs). However, the understanding of the origin of Cs-rich geyserite formed by hot springs remains unclear. In [...] Read more.
Recent studies have shown that the geothermal systems in Tibet are rich in rare metal elements such as lithium (Li), boron (B), rubidium (Rb), and cesium (Cs). However, the understanding of the origin of Cs-rich geyserite formed by hot springs remains unclear. In this study, a detailed petrological, elemental geochemical, and strontium–neodymium (Sr–Nd) isotopic investigation on Cs-rich geyserite in the Chabu region revealed that opal was the main mineral component of Chabu geyserite; here, some samples were rich in terrigenous clastic material, and well-developed diatom fossils were also present. Chabu geyserite had high contents of SiO2 (78.95%–94.72%) and Al2O3 (3.02%–8.14%) and low contents of Fe2O3 (0.21%–1.94%), TiO2 (0.01%–0.20%), MnO (0.01%–0.15%); additionally, the Fe/Ti ratio, the Al/(Al + Fe) ratio, and the Al/(Al + Fe + Mn) ratio showed large variations. These results indicated different degrees of participation by the terrigenous materials, hydrothermal deposition, and biogenic processes. Chabu geyserite was depleted in transition metal elements (e.g., Sc, V, and Cr) and high field strength elements (e.g., Nb, Zr, and Hf), relatively enriched in large-ion lithophile elements (e.g., Li, Rb, Sr, and Ba), and strongly enriched in Cs, (by up to 100 times the Cs content in the upper crust); in addition, it had low V/Y (1.30–2.00) and U/Th ratios. Chabu geyserite exhibited a right-dipping rare earth element (REE) distribution pattern and had significant negative Eu anomalies (0.26–0.72) and no or weak positive Ce anomalies (0.97–1.36). These results further indicated the influence of terrigenous clastic materials and nonhydrothermal sedimentation factors. The Sr–Nd isotopic composition of Chabu geyserite was significantly different from that of the mantle, with relatively high 87Sr/86Sr ratios (0.7070–0.7076) and low 143Nd/144Nd ratios (0.512223–0.512314). These ratios were similar to those of the crust. Combined with previous studies, the results from this study indicated that Chabu geyserite was a Cs-rich geyserite and was formed in an intracontinental post-collisional orogenic environment, mainly from crustal material, with the participation of biological and hydrothermal processes. Full article
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<p>Diagram of active tectonic system and geothermal distribution in Tibet (after [<a href="#B33-minerals-15-00036" class="html-bibr">33</a>]). (1) Boundary faults and fault depression zones primarily characterized by normal faulting; (2) boundary faults primarily characterized by strike-slip motion; (3) suspected active faults; (4) early compressive deep faults; (5) typical Quaternary geothermal spring display areas; (F1) Southern Tibet detachment; (F2) Yarlung Zangbo deep fault; and (F3) Bangong Co–Nujiang Fault zone.</p>
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<p>Geological map of the Chabu geothermal field (after [<a href="#B34-minerals-15-00036" class="html-bibr">34</a>]).</p>
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<p>Chabu Geyserite outcrop and structure. (<b>a</b>,<b>b</b>) Profile outcrop; (<b>c</b>) lamellar structure; (<b>d</b>) massive structure; (<b>e</b>) vesicular structure; (<b>f</b>) crusty structure.</p>
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<p>Chabu Geyserite structure. (<b>a</b>) Brecciated vein debris; (<b>b</b>) mineral debris such as quartz and feldspar; (<b>c</b>) gelatinous opal; (<b>d</b>) diatom organism.</p>
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<p>Spidergrams of the Chabu geyserite (<b>a</b>) and REE patterns (<b>b</b>). The value of upper crust shale from Rudnick and Gao [<a href="#B36-minerals-15-00036" class="html-bibr">36</a>]. The value of North American from McDonough and Sun [<a href="#B39-minerals-15-00036" class="html-bibr">39</a>].</p>
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<p>Plots of (<b>a</b>) Al<sub>2</sub>O<sub>3</sub> vs. SiO<sub>2</sub> and (<b>b</b>) Al<sub>2</sub>O<sub>3</sub> vs. TiO<sub>2</sub> for Chabu geyserite.</p>
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<p>Diagrams of Al/(Al + Fe + Mn) vs. Fe/Ti for Chabu geyserite (after [<a href="#B51-minerals-15-00036" class="html-bibr">51</a>]).</p>
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<p>Triangular diagrams of Fe-Mn-Al in Chabu geyserite (after [<a href="#B48-minerals-15-00036" class="html-bibr">48</a>]).</p>
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<p>Diagrams of Th vs. U for Chabu geyserite (after [<a href="#B14-minerals-15-00036" class="html-bibr">14</a>,<a href="#B47-minerals-15-00036" class="html-bibr">47</a>]).</p>
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<p>Diagrams of Cr vs. Zr for Chabu geyserite (after [<a href="#B14-minerals-15-00036" class="html-bibr">14</a>]).</p>
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<p>Diagrams of εNd vs. εSr for Chabu geyserite. The mantle, lithosphere mantle, upper crust and lower crust values are from Zhao [<a href="#B63-minerals-15-00036" class="html-bibr">63</a>].</p>
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22 pages, 23559 KiB  
Article
Application of Magnetometer-Equipped Drone for Mineral Exploration in Mining Operations
by Dimitris Perikleous, Katerina Margariti, Pantelis Velanas, Cristina Saez Blazquez, Pedro Carrasco Garcia and Diego Gonzalez-Aguilera
Drones 2025, 9(1), 24; https://doi.org/10.3390/drones9010024 - 30 Dec 2024
Viewed by 526
Abstract
This study investigates the geological composition and material distribution within the Lavrion repository located in Greece through an aerial magnetometry survey using a novel aerial drone, CERBERUS, coupled with advanced data processing techniques. The deployment of drone-based magnetometry provided a high-resolution, non-invasive approach [...] Read more.
This study investigates the geological composition and material distribution within the Lavrion repository located in Greece through an aerial magnetometry survey using a novel aerial drone, CERBERUS, coupled with advanced data processing techniques. The deployment of drone-based magnetometry provided a high-resolution, non-invasive approach to capturing magnetic field data over complex and potentially hazardous terrain (soils highly contaminated), facilitating the rapid and precise mapping of the study area. As a final result, a 3D magnetic susceptibility model was developed, representing a detailed view of the magnetic susceptibility variations within the repository. This model enabled the comprehensive visualization of high-susceptibility zones associated with ferromagnetic materials and low-susceptibility zones correlating with diamagnetic materials like lead, arsenic, cadmium, and zinc. The combined methodologies underscore the effectiveness of drone-based aerial magnetometry in geophysical studies, highlighting its potential for mining exploration and waste management. This study demonstrates that the integration of drone technology with magnetic data processing offers a powerful tool for analysing subsurface structures in a safe, efficient, and non-invasive manner. Full article
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<p>Geological overview: (<b>a</b>) Simplified geological map of the Lavrion ore district [<a href="#B22-drones-09-00024" class="html-bibr">22</a>]; (<b>b</b>) Geological sketch map of the Plaka area [<a href="#B22-drones-09-00024" class="html-bibr">22</a>].</p>
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<p>UAV 3D designs. (<b>a</b>) UAV frame; (<b>b</b>) arm mount; (<b>c</b>) UAV cover.</p>
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<p>Manufactured UAV frame.</p>
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<p>Arms with motors and propellers: (<b>a</b>) 3D designed; (<b>b</b>) prototype manufactured.</p>
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<p>Frame and arms assembled: (<b>a</b>) 3D designed—top view; (<b>b</b>) manufactured—top view.</p>
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<p>Landing gear: (<b>a</b>) 3D designed—trimetric view; (<b>b</b>) manufactured—trimetric view.</p>
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<p>CERBERUS UAV: (<b>a</b>) 3D designed; (<b>b</b>) Manufactured.</p>
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<p>CERBERUS UAV with the GSMP-35U magnetometer: (<b>a</b>) CERBERUS UAV take off; (<b>b</b>) Field data collection. Considering the potential impact of unfavourable weather conditions on data collection, the campaigns were conducted under optimal environmental conditions (as illustrated in <a href="#drones-09-00024-f008" class="html-fig">Figure 8</a>), ensuring minimal magnetometer oscillations.</p>
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<p>Drone-based magnetometer data processing workflow.</p>
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<p>Magnetic properties of the elements.</p>
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<p>Total magnetic field (coordinate reference system—CRS: WGS84). While the data may appear smoothed, no smoothing filters were applied in this study. An analysis using the OASIS Montaj ‘airborne quality control’ module was conducted to check for heading errors and none were detected. Additionally, it is worth noting that a potassium magnetometer was employed, which is less susceptible to heading errors compared to other technologies, such as proton magnetometers [<a href="#B38-drones-09-00024" class="html-bibr">38</a>].</p>
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<p>Total Magnetic Field Reduced to Pole (CRS: WGS84).</p>
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<p>Analytic signal (CRS: WGS84).</p>
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<p>(<b>a</b>) TILT derivative (WGS84 35N); (<b>b</b>) Interpretation of TILT derivative (WGS84).</p>
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<p>Interpretation of the TILT derivative and Magnetic Field Reduced to Pole (CRS: WGS84).</p>
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<p>Pseudo gravity (CRS: WGS84).</p>
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<p>3D magnetic susceptibility block model (CRS: WGS84 35N).</p>
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<p>Comparison of measured and forward-modelled magnetic anomalies and their residuals. (<b>a</b>) Measured magnetic anomalies (nT) from UAV data. (<b>b</b>) Forward-modelled magnetic anomalies (nT) derived from the 3D magnetic susceptibility inversion. (<b>c</b>) Residual magnetic field map.</p>
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<p>3D magnetic susceptibility model with orthoimage (CRS: ETRS84 35N).</p>
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<p>3D magnetic susceptibility model with orthoimage (CRS: ETRS84 35N).</p>
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<p>3D model of magnetic susceptibility: (<b>a</b>) High magnetic susceptibility values; (<b>b</b>) Close to zero or negative magnetic susceptibility values.</p>
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24 pages, 3278 KiB  
Review
Metallogenic Evolution Related to Mantle Delamination Under Northern Tunisia
by Nejib Jemmali, Fouad Souissi, Larbi Rddad, Emmanuel John Carranza and Guillermo Booth-Rea
Minerals 2025, 15(1), 31; https://doi.org/10.3390/min15010031 - 30 Dec 2024
Viewed by 531
Abstract
Mineralization processes in the Tell-Atlas of North Africa coincided with magmatism, extension, and lithospheric rejuvenation during the middle to late Miocene. This review examines the lead isotope compositions and Pb-Pb age dating of ore deposits in the region to elucidate the sources and [...] Read more.
Mineralization processes in the Tell-Atlas of North Africa coincided with magmatism, extension, and lithospheric rejuvenation during the middle to late Miocene. This review examines the lead isotope compositions and Pb-Pb age dating of ore deposits in the region to elucidate the sources and timing of mineralization events. The data reveal a predominantly radiogenic signature in the ores, indicating that the primary component is from a crustal source, with a contribution from the mantle. Pb-Pb age dating suggests the ranges of mineralization ages, with late Miocene events being particularly significant, coinciding with proposed sub-continental mantle delamination following subduction of the African lithosphere. In this context, polymetallic mineralizations formed related to felsic magmatism, hydrothermalism driven by extensional faults, resulting in the formation of Mississippi Valley-Type, and Sedimentary exhalative deposits within associated semi-grabens and diapirism. The correlation between orogenic extensional collapse, magmatism, and mineralization underscores the importance of understanding the specific geological context of ore formation. The detachment of subducted slabs and subsequent influx of hot asthenosphere play pivotal roles in creating conducive conditions for mineralization. This study sheds light on the intricate interplay between tectonic mechanisms, mantle-crust interactions, and mineralization events in the Tell-Atlas, offering insights for further exploration in the region. Full article
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<p>Tectonic sketch of the western Mediterranean basins and orogens. Modified from [<a href="#B31-minerals-15-00031" class="html-bibr">31</a>]. The box shows the Nappes zone location.</p>
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<p>Simplified geologic map of northern Tunisia (modified from [<a href="#B71-minerals-15-00031" class="html-bibr">71</a>,<a href="#B72-minerals-15-00031" class="html-bibr">72</a>,<a href="#B73-minerals-15-00031" class="html-bibr">73</a>]) with the distribution of ore deposits, magmatic rocks, and deep-seated faults. GHCS: Ghardimaou-Cap Serrat Fault. RKTF: Ras el Korane-Thibar Fault. ETF: El Alia-Teboursouk Fault. TEF: Tunis-Elles Fault. SD-DH-OB: Sidi Driss-Douahria-Oued Belif, JA-AA: Jebel Arja-Ain Allega, RR: Ras Rajel, OM: Oued Maden, FH: Fedj Hassene, AB-CH: Ain el Bey-Chouichia, SB-JH: Sidi Bouaouane-Jebel Hallouf, BZ: Bazina, SM; Semmene, JL-BA: Jalta-Bir Afou, JG: Jebel Ghozlane.</p>
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<p>Lead isotope compositions of galena from selected Tunisian Nappes zone ore deposits plotted on <sup>207</sup>Pb/<sup>204</sup>Pb vs. <sup>206</sup>Pb/<sup>204</sup>Pb and <sup>208</sup>Pb/<sup>204</sup>Pb vs. <sup>206</sup>Pb/<sup>204</sup>Pb diagrams, together with Nefza-La Galite-Algeria Neogene magmatic rocks [<a href="#B28-minerals-15-00031" class="html-bibr">28</a>,<a href="#B125-minerals-15-00031" class="html-bibr">125</a>], and Alboran sea volcanic rocks [<a href="#B126-minerals-15-00031" class="html-bibr">126</a>]. Sources of data for Tunisian ore deposits (see <a href="#app1-minerals-15-00031" class="html-app">Table S2</a>).</p>
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<p>Δγ–Δβ genetic classification diagram after [<a href="#B124-minerals-15-00031" class="html-bibr">124</a>] showing lead isotope composition of Nappes zone ores (1: mantle lead, 2: upper crustal lead, 3: mixed upper crustal and mantle lead-3a: magmatism, 3b: sedimentation, 4: chemical deposit lead, 5: submarine hydrothermal lead, 6: medium-high grade metamorphic lead, 7: hypometamorphic lower crustal lead, 8: orogenic belt lead, 9: ancient shale upper crustal lead, and 10: retrograde metamorphic lead) (Δβ = [β/βM(t) − 1] × 1000; Δγ = [γ/γM(t) − 1] × 1000; β = <sup>207</sup>Pb/<sup>204</sup>Pb; γ = <sup>208</sup>Pb/<sup>204</sup>Pb; βM(t) = 15.33; γM(t) = 37.47).</p>
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<p>Lead isotope compositions of galena from selected Tunisian Nappes zone ore deposits plotted on a <sup>207</sup>Pb/<sup>204</sup>Pb vs. <sup>206</sup>Pb/<sup>204</sup>Pb diagram for comparison together with the ores of Algerian Tell [<a href="#B131-minerals-15-00031" class="html-bibr">131</a>], Morocco Rif [<a href="#B132-minerals-15-00031" class="html-bibr">132</a>], and southeastern Spain [<a href="#B133-minerals-15-00031" class="html-bibr">133</a>].</p>
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<p>Scattergrams for the Nappes zone ore deposits, showing relationships between (<b>A</b>) <sup>207</sup>Pb/<sup>204</sup>Pb and μ, and (<b>B</b>) model age and μ. Model ages and μ were calculated using the equation of [<a href="#B133-minerals-15-00031" class="html-bibr">133</a>].</p>
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<p>Model age distribution of galena ores [<a href="#B24-minerals-15-00031" class="html-bibr">24</a>,<a href="#B26-minerals-15-00031" class="html-bibr">26</a>,<a href="#B27-minerals-15-00031" class="html-bibr">27</a>,<a href="#B28-minerals-15-00031" class="html-bibr">28</a>] and magmatic rocks [<a href="#B28-minerals-15-00031" class="html-bibr">28</a>,<a href="#B87-minerals-15-00031" class="html-bibr">87</a>,<a href="#B91-minerals-15-00031" class="html-bibr">91</a>,<a href="#B104-minerals-15-00031" class="html-bibr">104</a>] of the Nappes zone. Dotted line corresponds to the mean value. The solid line corresponds to the outlier.</p>
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<p>(<b>a</b>) Cartoon of the tectonic mechanisms driving lithospheric rejuvenation, crustal extension, magmatism, and associated metal endowment in Northern Tunisia and Algeria during the middle to late Miocene (<b>b</b>) Schematic cross-s ection 1-1’across Northern Algeria-Tunisia showing the driving mechanisms and tectonic setting of different ore deposits in the region at the time of deposition. Notice the North to South crustal thinning gradient, taken from the EGT’85 refraction seismic experiment (99), and the occurrence of magmatic outcrops and a high-velocity lower crustal domain that are present towards the North. NSA: North-South Axis. TA-STEP: Tunisian Atlas Step Fault. T-STEP: Tyrrhenian Step Fault. PR: Pantelleria rift. LAB: Lithosphere Asthenosphere Boundary.</p>
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21 pages, 5602 KiB  
Article
Quantitative Inversion of Martian Hydrous Minerals Based on LSTM-1DCNN Model
by Xinbao Liu, Ming Jin, Xiangnan Liu, Zhiming Yang, Zengqian Hou and Xiaozhong Ding
Remote Sens. 2025, 17(1), 94; https://doi.org/10.3390/rs17010094 - 30 Dec 2024
Viewed by 428
Abstract
Hydrous minerals are significant indicators of the ancient aqueous environment on Mars, and orbital hyperspectral data are one of the most effective tools for obtaining information about the distribution of hydrous minerals on the Martian surface. However, prolonged weathering, erosion, and other external [...] Read more.
Hydrous minerals are significant indicators of the ancient aqueous environment on Mars, and orbital hyperspectral data are one of the most effective tools for obtaining information about the distribution of hydrous minerals on the Martian surface. However, prolonged weathering, erosion, and other external forces result in complex mixing effects, often weakening the spectral absorption features of individual minerals. This study proposes a quantitative inversion method for Martian hydrous minerals by integrating a radiative transfer model with a deep learning network. Based on the physics of the Hapke radiative transfer model, the single-scattering albedo spectra of mineral end members were obtained. Additionally, the Linear Spectral Mixture Model was employed to generate a large number of fully constrained mineral mixture samples, providing theoretical support for experimental data. An LSTM-1DCNN model was trained to establish a data-driven quantitative inversion framework. CRISM data were applied to the Eberswalde Crater region to retrieve the abundances of 21 hydrous minerals, including tremolite, opal, and serpentine. The average abundance of hydrous minerals was calculated to be 0.018, with a total area proportion of approximately 8%. Additionally, by analyzing the distribution areas of hydrous silicates, hydrous sulfates, and hydrous hydroxides, the water activity history of the region was inferred. The results align with findings from related studies and mineral spectral index results. By incorporating deep learning into traditional mixing models, this study identifies the distribution of various low-abundance hydrous minerals, enhancing the accuracy of Martian hydrous mineral inversion. It is expected to provide valuable references for the selection of landing sites for Tianwen-3 and support the smooth implementation of China’s Mars exploration mission. Full article
(This article belongs to the Special Issue Planetary Geologic Mapping and Remote Sensing (Second Edition))
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<p>Overview map of the Eberswalde crater on Mars and the study area FRT000060dd. The Eberswalde crater underwent significant post-impact modifications, leaving only the northeastern crater rim intact. The FRT000060dd image is located northwest of the Eberswalde crater. The western part of the crater features a prominent valley where a river connects to the alluvial fan within the image coverage, forming a relatively complete aqueous landform. The base map data are CTX images.</p>
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<p>Technology roadmap.</p>
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<p>LSTM model structure diagram and Bi-LSTM layer structure diagram, where the LSTM layer neuron structure is referenced from Li et al. [<a href="#B32-remotesensing-17-00094" class="html-bibr">32</a>].</p>
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<p>1DCNN structure and data chart.</p>
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<p>Model accuracy, precision, recall, and F1 score trends as <span class="html-italic">T</span><sub>1</sub> changes.</p>
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<p>Qualitative network mineral identification accuracy chart.</p>
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<p>Scatter plot of the test set for multi-batch training of the quantitative network. Panels (<b>a</b>–<b>f</b>) represent the results for 1DCNN training batches of 100, 150, 200, 250, 300, and 350, respectively.</p>
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<p>Box plot of predicted mineral abundance within the FRT000060dd map area.</p>
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<p>Statistical chart of the pixels occupied by major minerals.</p>
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<p>Comparison of model inversion results and CRISM data. (<b>a</b>) A false-color RGB image (red = 2.5295 μm, green = 1.5066 μm, blue = 1.0800 μm). The red arrow indicates the pixel location. In (<b>b</b>), the solid black line represents the orbital spectral curve of the pixel, whereas the dashed black line shows the simulated spectral curve based on the inversion results. The other dashed, colored lines correspond to the end-member spectra. The variations observed in the 1.4–1.55 μm range, marked by the arrow, result from instrumental errors [<a href="#B33-remotesensing-17-00094" class="html-bibr">33</a>], whereas the sharp peaks in the 1.9–2.1 μm range, also marked by an arrow, are due to atmospheric correction related to CO<sub>2</sub> [<a href="#B10-remotesensing-17-00094" class="html-bibr">10</a>].</p>
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<p>The distribution map of hydrous mineral types: (<b>a</b>) hydrous sulfate minerals, which have been highlighted with a red box, (<b>b</b>) hydrous hydroxide minerals, and (<b>c</b>) hydrous silicate minerals. The bottom figure is the gray-scale data for the 1.1652 μm.</p>
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<p>A comparison between mineral abundance inversion results and mineral spectral indices. Panels (<b>a</b>,<b>b</b>) represent the Olivine abundance and Olivine Index. The red rectangular region in Panel (<b>a</b>) represents a potential olivine distribution area. Panel (<b>c</b>) illustrates the scatter plot corresponding to the data presented in Panels (<b>a</b>,<b>b</b>); the Pearson Correlation Coefficient (ρ) between the two variables in Panel (<b>c</b>) is 0.666, indicating a moderately strong positive correlation. Panels (<b>d</b>,<b>e</b>) represent the Pyroxene abundance and Pyroxene Index. Panel (<b>f</b>) illustrates the scatter plot corresponding to the data presented in Panels (<b>d</b>,<b>e</b>); the ρ between the two variables in Panel (<b>f</b>) is 0.335, indicating a certain positive correlation.</p>
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<p>Horizontal and vertical elevation distribution maps of the three types of hydrous minerals. (<b>a</b>) The horizontal distribution of three types of hydrous minerals: hydrous sulfate minerals, hydrous hydroxide minerals, and hydrous silicate minerals. (<b>b</b>,<b>c</b>) The AA’ and BB’ cross-sectional profiles corresponding to (<b>a</b>), respectively, showing the elevation distribution of different minerals along and near the section lines.</p>
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