The Xiaohengjiang gold deposit, situated in northeastern Hunan Province, represents a significant recent discovery within the Guanzhuang gold deposit comprehensive exploration area in Liling City, Hunan Province. This deposit encompasses the Tieshijian and Taohua ore sections and is hosted within the Huanghudong Formation of the Lengjiaxi Group, part of the Neoproterozoic Qingbaikou Formation. Its formation and spatial distribution are predominantly influenced by nearly north-south-oriented fault structures. The primary ore types present include fractured-altered slate and sulfide quartz vein gold ores. Currently, the deposit is classified as having a medium resource scale, with substantial potential for further exploration and resource expansion. Despite its geological importance, there has been limited research investigating the relationship between acidic magmatic rocks and gold mineralization in this region. To address this research gap, the present study concentrates on the geochronology, petrogenesis, and tectonic implications of the granodiorite veins exposed within the mining area. Utilizing zircon LA-ICP-MS U-Pb dating techniques, the emplacement age of the granodiorite veins was determined to be in the Early Paleozoic［（437.2±8.0）Ma］. This result suggests that the gold mineralization events in the region are temporally linked to Caledonian magmatic activities, indicating an association with regional tectonomagmatic processes. The granodiorite veins exhibit high silicon content, moderate aluminum levels, and are enriched in alkali elements, while displaying low concentrations of iron, magnesium, manganese, and phosphorus, characteristics typical of S-type granites. The rare earth element（REE） distribution patterns demonstrate a rightward decline, accompanied by a weak negative Eu anomaly and significant enrichment in large-ion lithophile elements（LILEs） such as Rb, Th, U, and La. In contrast, high-field-strength elements（HFSEs）, including Nb, Sr, P, and Ti, show notable depletion. These geochemical attributes suggest that the granodiorite veins originated from crustal sedimentary sources through partial melting and underwent substantial fractional crystallization during their formation.Furthermore, the granodiorite veins are postulated to have formed within a tectonic environment transitioning from a syn-collisional to a post-collisional extensional regime. This transitional setting facilitated the interaction between tectonic and magmatic processes, thereby contributing to gold mineralization. A comprehensive analysis confirms a spatial and temporal correlation between Caledonian magmatic activities and gold mineralization events. Based on these findings, it is recommended that future exploration efforts concentrate on areas surrounding Caledonian intrusive rocks. These areas may possess untapped mineralization potential, offering opportunities for the discovery of new gold resources. This approach not only enhances the understanding of mineralization processes but also provides practical guidance for regional gold exploration and resource development strategies.

The Xilin area in Guangxi is geologically positioned within the Xilin-Baise fault-fold belt of the Northwest Guangxi Depression on the Yangtze Plate, representing a vital segment of the Au-Sb polymetallic metallogenic belt in the western Guangxi-southwestern Guizhou-southeastern Yunnan region, also known as the Youjiang Basin. To explore the distribution characteristics of ore-forming elements and mineralized bodies, and to achieve advancements in mineral exploration, this study implemented a 1∶10 000 scale soil geochemical survey and prospecting prediction. Through a systematic analysis of geochemical parameters, correlation coefficients, spatial distribution patterns, and single-element/composite anomalies using indicator elements (Au, Ag, As, Sb), three key anomalous zones (GXB-1, GXB-2, GXB-3) were identified for prioritized exploration. The key findings indicate that Au and Sb exhibit high concentration and variation coefficients, suggesting a strong metallogenic potential. Significant correlations have been identified among Au, Sb, and As, indicating their potential as indicator element associations. The skewed distribution patterns of Au and Sb suggest the presence of secondary enrichment processes. An integrated analysis of metallogenic characteristics and geochemical anomalies has led to the identification of five single-element anomalies and two composite anomalies. Trenching verification has revealed three auriferous mineralized zones. The gold mineralization predominantly occurs in silicified clastic rocks of the Baifeng Formation, specifically at structural contacts between NW-trending cross-layer fractures and interlayer fracture zones. These structural features have been established as key indicators for prospecting in future exploration endeavors.

As mining activities continue to intensify, underground roadways encounter unprecedented stability challenges due to increasingly complex stress environments, dynamic geological variations, and anthropogenic disturbances. Accurate prediction of roadway deformation is essential for ensuring mining safety and optimizing operational layouts. However, conventional single neural network models often struggle to effectively capture both abrupt local features and long-term evolutionary trends in nonlinear displacement time series. To address these limitations, this study introduces an innovative hybrid model combining a Temporal Convolutional Network and Long Short-Term Memory（TCN-LSTM-AddAttn） architecture, enhanced with an additive attention mechanism, to achieve high-precision predictions of roadway deformation. The proposed architecture employs a parallel framework to leverage the strengths of both TCN and LSTM. An additive attention mechanism is incorporated to dynamically prioritize critical patterns from both networks. The model employs learnable parameters to calculate feature similarity and utilizes the Softmax function to generate normalized weights, facilitating the adaptive fusion of multi-scale representations. Validation of the model is conducted using displacement data from four monitoring points(W1430-10, W1430-11, W1480-7, W1530-11) across various roadways in the Yunnan Zizou iron mine. Data preprocessing involves the removal of outliers using a Hampel filter, interpolation of missing values via cubic spline, and min-max normalization to standardize input scales. The processed data are divided into training, validation, and test sets in an 8∶1∶1 ratio. Hyperparameters, including TCN channels (32), LSTM hidden dimensions (64), batch size (32), and learning rate (0.001), are optimized through grid search to ensuring generalization across diverse mining scenarios. Experimental results indicate that the TCN-LSTM-AddAttn model outperforms standalone TCN, LSTM, and the TCN-LSTM hybrid models. In the case of W1430-10, the TCN-LSTM-AddAttn model demonstrates a Mean Absolute Error (MAE) of 0.0292 mm, representing a 47.95% reduction compared to the TCN-LSTM model. Additionally, it achieves a Root Mean Square Error (RMSE) of 0.0396 mm, marking a 37.34% reduction, and a Symmetric Mean Absolute Percentage Error (SMAPE) of 0.0337, indicating a 47.91% reduction. The Adjusted R² (R _adj) value of 0.9861 suggests near-perfect prediction accuracy. For W1430-11, the model records an MAE of 0.0282 mm (28.79% reduction), an RMSE of 0.0366 mm (27.52% reduction), a SMAPE of 0.0738 (28.70% reduction), and an R _adj of 0.9799. Comparable improvements are noted for W1480-7 and W1530-11, with prediction errors consistently remaining below 0.1 mm. By incorporating multi-scale feature decoupling and dynamic weighting, the proposed model offers robust technical support for assessing mine roadway stability, identifying risk zones, and providing early safety warnings.

In recent years, substantial advancements have been achieved in the exploration of gold deposits within the Back-Longmenshan tectonic belt, which boasts a resource of approximately 50 tons. The Xinjiazui gold deposit, a newly identified site within this belt, exhibits medium to large prospecting potential. The gold deposits are predominantly located within the northeast-trending Yanzibian-Huashigou brittle-ductile shear zone, with the formation of ore bodies and mineralized bodies being stringently governed by these shear zones. The host rock primarily comprises iron bearing magnesite spotted phyllite and carbonaceous silica slate. The predominant ore type is quartz vein, and the mineralization alterations closely associated with gold include silicification, pyritization, and minor arsenopyritization.While previous researchers have made certain advancements in the study of this ore deposit, there remains a relative paucity of research focused on its mineralogical aspects. This study, grounded in comprehensive field investigations, concentrates on the gold-bearing minerals pyrite and arsenopyrite. Utilizing methodologies such as microscopic observation, back-scattered electron(BSE) imaging, and electron probe micro-analysis(EPMA), the research aims to elucidate the mineralogical characteristics of these gold-bearing minerals, investigate the occurrence state of gold, and determine the physical and chemical conditions of mineralization, as well as the genesis of mineral deposits. The findings indicate that the hydrothermal mineralization process can be categorized into three distinct stages: Stage Ⅰ, characterized by quartz-pyrite formation; Stage Ⅱ, defined by quartz-calcite-natural gold polymetallic sulfide, development; and Stage Ⅲ, marked by quartz-carbonate, formation, with Stage II being identified as the principal mineralization phase. Pyrite is classified into three generations:the sedimentary diagenesis stage(Py0), the early mineralization stage(Py1), and the main mineralization stage(Py2), during which arsenopyrite coexists with the main stage pyrite. Gold is present in two forms: visible gold and invisible gold. Visible gold appears in the main mineralization stage of pyrite as encapsulated and fractured gold. The occurrence of invisible gold exhibits distinct variations. During the sedimentation and early mineralization stages, gold within pyrite is present as nano gold(Au0). In contrast, during the main mineralization stage, pyrite contains both nano gold(Au0) and lattice gold(Au⁺). In arsenopyrite, all gold exists exclusively as lattice gold(Au⁺). The Xinjiazui gold deposit was formed under medium-high temperature conditions at a moderate to considerable depth, with f(S₂) values ranging from -8.5 to -4.5. When compared to typical ductile shear zone-type gold deposits in the Longmen shan orogenic belt, and considering the geological and geochemical characteristics, it is inferred that the Xinjiazui gold deposit is an orogenic gold deposit influenced by brittle-ductile shear zones.

High-quality and stable backfill is a crucial technical requirement for ensuring safe and efficient mining operations. This study addresses the issue of unstable backfill quality in a gold mine, which adversely impacts stope safety and production efficiency, by exploring the feasibility and optimization of paste backfill utilizing fine-grained tailings. Through comprehensive testing of the tailings’ fundamental physical and chemical properties, flocculation settling behavior, slurry flow characteristics, and numerical simulation of pipeline transportation, optimal backfill process parameters were identified. The test results indicate that the tailings possess a specific gravity of 2.651 g/cm³, a natural bulk density of 0.967 g/cm³, with particles smaller than 74 μm comprising 71.33%, categorizing them as typical fine-grained tailings. Flocculation settling tests reveal that a feed concentration of 12% and a flocculant dosage of 30 g/t yield optimal settling performance, achieving a bottom flow concentration of 53.38%. The incorporation of a rake mechanism further enhances the bottom flow concentration to 61.35%. Rheological assessments reveal that the fine-grained composite tailings slurry behaves as a non-Newtonian fluid characterized by yield stress, aptly described by the Bingham model. The findings indicate that the slurry’s mass concentration substantially influences its flowability, with increased concentration correlating with decreased flowability, whereas the ash-to-sand ratio exerts a comparatively minor influence. Furthermore, numerical simulations of pipeline transport demonstrate that when the slurry concentration surpasses 65%, the slurry maintains uniform flow within the pipeline, devoid of stratification or segregation. The velocity profile displays typical fluid dynamic characteristics, exhibiting higher velocities at the pipe center and lower velocities near the pipe wall. Mass concentration, inlet flow rate, and pipe diameter significantly impact resistance loss, while the ash-to-sand ratio has a lesser effect. Specifically, reducing the mass concentration, enhancing the inlet flow rate, or decreasing the pipe diameter results in increased resistance loss within the pipeline. These research outcomes furnish a theoretical foundation and practical guidance for optimizing fine-grained tailings paste backfill processes and pipeline system design, improving backfill quality and system stability, and supporting safe and efficient mine production.

To establish a foundation for assessing the feasibility of comprehensive utilization of mineral resources in a lead-zinc ore, an extensive investigation into process mineralogy and beneficiation testing was conducted. This study employs a range of analytical techniques, including chemical analysis, X-ray diffraction analysis, optical microscopy, scanning electron microscopy, energy-dispersive spectroscopy micro-area composition analysis, and mineral liberation analysis (MLA), to examine the chemical composition, mineral composition, and occurrence state of the primary minerals—lead, zinc, and silver—within the ore. The research focuses on identifying the key mineralogical factors influencing mineral processing efficacy. Subsequently, the beneficiation process and achievable separation indices of the ore were determined through beneficiation testing. The findings indicate that the mineral composition of the ore is relatively complex, with the predominant metal minerals being galena, sphalerite, and pyrite, while argentite is the sole silver mineral present. The gangue minerals predominantly comprise feldspar (including both potassium feldspar and plagioclase feldspar), quartz, and chlorite, with subordinate amounts of sericite, biotite, rhodochrosite, and fluorite. The principal recoverable elements in the ore, through beneficiation, are lead (Pb), zinc (Zn), and silver (Ag), with concentrations of 2.72%, 2.28%, and 65.00×10^-6, respectively. Lead is primarily present as lead sulfide, constituting 89.34%, followed by lead sulfate at 7.72%. Zinc predominantly occurs as zinc sulfide (sphalerite), accounting for 95.61% of its presence. Silver is mainly found as silver sulfide (argentite), comprising 65.68% of its occurrence. This ore is characterized as a silver-bearing primary lead-zinc sulfide ore with a typical disseminated structure.The primary mineralogical factors influencing the beneficiation outcomes are as follows: Firstly, the complex and irregular output forms of galena and sphalerite within the ore, along with their intricate intergrowth, significantly impact the quality and recovery rates of lead and zinc concentrates. Secondly, the close association between argentite and galena, followed by sphalerite, dictates the pathway for silver enrichment. Based on the ore’s characteristics and preliminary exploratory tests, beneficiation research was conducted utilizing a priority flotation process, specifically prioritizing lead flotation followed by zinc activation. This approach yielded stable test indices. The closed-circuit flotation test achieved a lead concentrate with a grade of 65.08% Pb and a recovery rate of 91.32%, and a zinc concentrate with a grade of 41.70% Zn and a recovery rate of 85.96%. Additionally, the valuable metal silver was significantly enriched in the lead concentrate, with a content of 1 323.80×10^-6 and a recovery rate of 79.28%. The outcomes of the beneficiation tests exhibit a high degree of consistency and alignment with the predictions made by process mineralogical studies.

Tailings dams, which are primarily utilized for the storage of tailings or industrial waste produced by mining activities, represent significant sources of high potential energy and pose considerable risks.A failure of such a dam could result in immeasurable losses.Consequently, online monitoring of tailings dams is essential for real-time analysis and risk mitigation.This monitoring is critical for promptly assessing the safety status of tailings dams, preventing dam failures, and safeguarding human lives and property. Therefore, anomaly detec-tion in time series data derived from tailings dam monitoring systems is of paramount importance. In response to the frequent occurrence of anomalies within multi-sensor monitoring systems for tailings dams, which severely affect safety assessments, this paper proposes an enhanced TCN-Transformer hybrid anomaly detection model.This model incorporates a temporal convolutional network （TCN） component into the traditional Transformer model, replacing the absolute position encoding mechanism.This approach effectively captures complex long-term dependencies in time series data, thoroughly integrates global temporal information, and enhances the model’s accuracy in anomaly detection.Moreover, the model’s self-attention mechanism has been optimized through the implementation of a branching structure design and the integration of maximum and minimum strategies.This enhancement enables the extraction of spatial features from tailings dam time series data, allowing reconstruction errors and correlation differences to reinforce each other during detection. Consequently, the model’s anomaly detection performance is improved. By employing a self-supervised training paradigm, the model reduces its dependence on large-scale supervised datasets, thereby enhancing its practicality and generalization capabilities.Experimental results demonstrate that the proposed TCN-Trans-former anomaly detection model achieves an average F1 score of 0.9486, marking a significant improvement in detection accuracy and performance over traditional models.This model holds substantial importance for anomaly detection and safety management in the context of tailings dam time series data.

The manganese deposits in China are predominantly of sedimentary type, having formed from the Middle Proterozoic to the Neoproterozoic, the Late Paleozoic, and the early Mesozoic eras. These deposits are chiefly located in South China, with the “Datangpo-type” manganese deposit serving as the most representative example. In recent years, notable advancements have been achieved in the study of marine sedimentary carbonate-type manganese deposits within the Carboniferous sedimentary rock series in western China. Several medium to large manganese deposits, including the Aoertuokanashi, Muhu, and Maerkantu deposits, have been discovered in succession. The Xiaoerbulake manganese deposit, which is the focus of this study, is a newly identified deposit, situated in the Aketao area of Xinjiang Province. This deposit formed at the margin of a continental rift basin, exemplified by Qiaerlong, and is found within the stratified gray-black manganese-mineralized, pyrite-bearing argillaceous limestone of the Lower Carboniferous Talong Group. The deposit is primarily characterized by the presence of three manganese-rich minerals: rhodochrosite, manganocalcite, and kutnohorite. To comprehensively examine the sources of ore-forming materials and the formation environment of the Xiaoerbulake manganese deposit, a series of petrographic, mineralogical, and lithogeochemical analyses were undertaken. The lithogeochemical data reveal that in comparison to the surrounding rocks, the manganese ore is characterized by titanium depletion and low SiO₂/Al₂O₃ ratios, indicative of high-iron, medium-phosphorus, low-grade manganese ore. Trace elements such as Rb, Ta, and Hf are relatively deficient, whereas Th, Sm, and Y are enriched. The distribution of rare earth elements（REE） shows a pattern of light REE depletion and high REE enrichment, marked by a weakly negative Ce anomaly, a positive Eu anomaly, and a positive Y anomaly, suggesting that the manganese deposit originated from submarine hydrothermal venting. Environmental discrimination analysis indicates that the Y/Ho ratio of the manganese ore aligns with values typical of Phanerozoic limestone; additionally, the Sr-Ba ratio, the weakly negative Ce anomaly, and the positive Y anomaly imply that manganese mineralization occurred in a brackish to hypersaline, relatively oxidized depositional environment. The mechanism of mineralization can be described as follows: during the late Paleozoic era, Fe-Mn-enriched polymetallic submarine hydrothermal fluids interacted with seawater. This interaction led to the preferential accumulation of Mn²⁺ and Fe²⁺ ions as mixed （Mn, Fe）-（oxy）hydroxide complexes within redox transition zones characterized by relatively oxygen-deficient, reducing, and mildly alkaline to acidic conditions. These complexes subsequently underwent diagenetic transformation through reactions with carbonate ions, resulting in the formation of manganese carbonate assemblages predominantly composed of rhodochrosite. These assemblages were then transported to favorable sedimentary depressions, where they co-precipitated with carbonate sediments, ultimately leading to the formation of the Xiaorbulak manganese deposit.

Utilizing the global refined copper trade volume data spanning from 2004 to 2023, we employ complex network analysis to construct both random and weighted networks, thereby examining the global refined copper trade patterns from three perspectives: the overall trade structure, trade associations, and the roles of major trading nations. Additionally, we apply an enhanced gravitational model to assess the potential of China’s refined copper trade with its top 10 trading partners. The findings reveal that: (1)The global refined copper trade exhibits characteristics of a small-world network, characterized by a multi-core trade association structure, evolving from an initial dominance by European and American countries to later incorporating nations from Asia, Africa, and the Middle East. (2)China and the United States emerge as principal importers of refined copper, while Chile, Peru, Japan, and Australia serve as major exporters. The United States and India function as pivotal intermediaries in the refined copper trade, with Germany and Italy acting as central hubs. (3)Among the top 10 trading partners, Chile and Australia present potential, for restructuring, whereas South Korea, the United States, and Zambia, exhibit significant potential. Additionally, Japan, the Philippines, Kazakhstan, Peru and Poland are potential pioneering. The study provides some policy recommendations for the development of international refined copper trade and China’s import of refined copper.

In the field of rock mass engineering, the precise simulation of the post-peak mechanical behavior of rocks is essential for ensuring engineering safety and for the prevention and management of disasters. To overcome the limitations associated with fixed parameter approaches in conventional Mohr-Coulomb models for simulating post-peak failure stages, this study introduces an innovative experimental data-driven multi-parameter dynamic collaborative correction method. Initially, by integrating Python with the FLAC^3D platform, we developed a real-time backpropagation algorithm alongside a three-dimensional constitutive field dynamic iteration model. This framework facilitates the multi-threaded collaborative optimization of parameters, including cohesion, internal friction angle, and dilatancy angle, via embedded interfaces. Subsequently, utilizing strain gradient adaptive theory, we devised a real-time data assimilation engine capable of dynamically adjusting constitutive parameters through cyclic correction mechanisms. This approach effectively addresses the modeling challenges posed by the nonlinear coupling effects inherent in traditional static segmentation methods, which exhibit errors exceeding 15%.During the validation process, a numerical model for uniaxial compression, with dimensions of 50 mm×50 mm×100 mm and comprising 2 541 mesh elements, was utilized. A Python script was employed to dynamically invoke the s.stress()[2][2] function in FLAC^3D, allowing for the extraction of stress fields. This process initiated multi-parameter collaborative corrections whenever the experimental data surpassed a deviation threshold of Δσ=0.01 MPa. The experimental findings demonstrate that the dynamically corrected model effectively captured the post-peak strain-softening behavior of the rock. The stress levels predicted by the original model consistently exceeded the actual values, whereas the stress simulations from the corrected model aligned closely with the experimental values, thereby completely mitigating the trend of overestimation. This study offers novel insights into optimizing the accuracy of rock parameter estimation and provides a scientific basis and guidance for geotechnical engineering design.

In the context of fostering sustainable and healthy development within the rare earth industry, it is imperative that enterprises adhere to environmentally compliant operations. Nonetheless, the industry is currently confronted with significant challenges, including environmental regulatory rent-seeking, inadequate oversight, and insufficient supervision. These issues not only jeopardize the industry’s sustainable development but also pose potential risks to ecological environments. This study introduces an innovative tripartite evolutionary game model that incorporates rare earth enterprises, local ecological-environmental bureaus, and the Ministry of Ecology and Environment （MEE）. An in-depth analysis was conducted to investigate the evolutionary strategies of each stakeholder under various scenarios, and the stability of system equilibrium points was thoroughly examined. Additionally, numerical simulations were utilized to systematically assess the impact of key parameter adjustments on strategy selection, thereby providing quantitative scientific evidence to inform the optimization of regulatory policies. The findings indicate that： （1） The implementation of a robust reward-punishment mechanism by the Ministry of Ecology and Environment （MEE） is crucial. This mechanism not only effectively mitigates rent-seeking behavior between rare earth enterprises and local environmental authorities but also steers all stakeholders towards environmentally compliant strategies by dynamically adjusting the intensity of incentives. （2） Excessively high reward levels may have detrimental effects, potentially reducing the central government’s motivation for stringent oversight. Consequently, a scientifically designed reward-punishment mechanism must ensure that “the aggregate of rewards/penalties for enterprises and the credit losses incurred under rigorous supervision surpass their rent-seeking benefits, or that the total rewards/penalties for local environmental bureaus exceed their collusion gains.” This is vital for ensuring the sustainable development of the industry. （3） The study underscores the limitations of singular governance approaches. The results demonstrate that relying solely on cost-benefit adjustments or traditional reward-punishment measures is inadequate for effective governance. It is recommended that the Ministry of Ecology and Environment （MEE） implement a collaborative governance strategy that capitalizes on the synergistic integration of reward-punishment and credit constraint mechanisms. By intensifying penalty severity and credit losses, alongside augmenting incentives and diminishing corporate environmental costs, the standardization of enterprise compliance can be more effectively realized.

The aim of this study is to determine the optimal width of mine pillars that ensure stability under room-and-pillar mining conditions. A phosphorus mine in Guizhou serves as a case study for this investigation. The research integrates theoretical analysis, numerical simulation, and on-site monitoring to examine the load-bearing mechanisms of mine pillars and their appropriate widths within the context of room-and-pillar mining. Additionally, the study explores the impact of pillar width on quarry stability and validates the proposed optimization plan for pillar dimensions through simulation tests and practical engineering applications. The findings indicate that, following the initial excavation of the quarry, the maximum vertical displacement of the quarry’s roof plate varies at each stage. The displacement distribution is predominantly symmetrical along the quarry’s center line and decreases progressively towards the sides of the center line. As the excavation of the mining pillar advances through each phase of the quarrying process, a positive correlation is discerned between the displacement changes within the quarry and the exposed quarry area. Simultaneously, the displacement of the peripheral rock overlying the quarry demonstrates a gradual reduction along the left and right sides of the quarry’s center line. The displacement and settlement values of the surrounding overlying rock progressively decrease along these sides, culminating in a final displacement pattern that resembles an ‘arch’ shape. Following the excavation of each stage of the ore body, a high-stress region emerges within each stage of the mine pillar and the mining airspace. The quarry’s mine pillar enters a yield state, with the vertical stress on the quarry’s roof plate being significantly lower than that on the mine pillar. Tensile stress predominantly occurs around the mining airspace. The maximum vertical displacement and settlement value, as well as the maximum vertical stress value of the quarry, are recorded at 41.5 mm and 76.17 MPa, respectively. Notably, there is no significant plastic damage to the mine pillar, with damage being confined to localized areas. Empirical evidence from field engineering practice indicates that the theoretical analysis supporting an 8-meter pillar width is justified. Throughout the various phases of the ore body re-mining process, the displacement and settlement of the mine pillar remain minimal, with a recorded maximum displacement of 13.37 mm and a peak stress of 3.45 MPa, the reby confirming the pillar’s stability. These findings offer valuable theoretical insights and technical support for the safe and efficient extraction of phosphorus mines under analogous conditions.

To investigate the influence of blasting disturbances on the surrounding rock of stopes in deep environments, this study developed a numerical model of a deep stope featuring staged longhole drilling, utilizing the discrete element method platform (PFC^3D) and based on the engineering conditions of a hard rock mine in southern China. A five-row fan-shaped blast hole configuration was designed, and numerical simulations of millisecond-delayed blasting were conducted. The findings indicate that distinct dynamic response characteristics are observed in various zones of the surrounding rock under multi-row blasting conditions. Notably, the particle vibration amplitudes in the goaf sidewalls initially increase and subsequently decrease as the blast hole row spacing increases. Additionally, the vibration of the roof shows a marked reduction when the spacing exceeds 1.5 meters, whereas the row spacing between 1.0 and 1.5 meters has a relatively minor effect. Significant vibration accumulation is anticipated on the bench face and free surface. Cumulative deformation damage is primarily observed in the left abutment, bench face, and roof of the goaf under blasting loads, while the right abutment exhibits minimal damage. A distinct strip-shaped damage zone is evident on the left abutment, and large-scale rock collapse is likely on the bench face. Field validation corroborates substantial collapse risks in the roof strata and localized damage zones in the left abutment, aligning with numerical predictions. This study offers practical guidance for optimizing blasting design and mitigating disaster risks in deep hard rock mining operations.

The Daju area is situated in Angren County, Xigaze City, Tibet, approximately 30 km southwest of the Zhunuo super large porphyry copper deposit. The Daju granite hosts a substantial development of tourmaline veins, which vary in width and can reach up to 1 meter at their widest point. Comprehensive analyses, including electron probe microanalysis and laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS）, have been conducted to elucidate the genesis, geochemical characteristics, and prospecting implications of these tourmaline veins. Based on microscopic examination and morphological characteristics, tourmaline in the Daju area can be categorized into three distinct types：（1） Fan-shaped tourmaline （Tur-Ⅰ）, predominantly subhedral to euhedral, exhibiting yellowish-brown to greenish-blue pleochroism, and possessing the largest particle size; （2） Cylindrical tourmaline （Tur-Ⅱ）, also subhedral to euhedral, primarily short columnar with cross-sections often triangular or polygonal, displaying yellow-green pleochroism and medium particle size; （3） Fine granular tourmaline （Tur-Ⅲ）, mostly anhedral and granular, generally amorphous, with yellowish-orange to green pleochroism, and characterized by the smallest particle size. All types of tourmalines have moderate Mg/（Mg+Fe） ratio, high Na/（Na+Ca） ratio, and low ^X□/（^X□+Na+K） ratio, belonging to the alkali group dravite tourmaline-black tourmaline solid solution series, and the main replacement mechanism of elements is Fe³⁺Al_-1 and （NaMg）（^X□Al）_-1. The elevated magnesium content （1.18~1.74 apfu）, strontium content （589×10^-6~1 943×10^-6）, vanadium content （154×10^-6~371×10^-6）, and the absence of aluminum cation at the Y position in the three types of tourmalines suggest a hydrothermal origin. In the graphical projection for Sr/Pb-Zn/Cu-Ga deposit type discrimination, tourmaline from the Daju area predominantly falls within the transition zone from metamorphic tourmaline to porphyry copper deposits. This suggests a potential genetic link between the formation of tourmaline in the Daju area and porphyry copper deposits. Trace element analysis reveals that Daju tourmaline exhibits a high Sr/Y ratio, elevated levels of Ba, Rb, and Ni, and a low Li content. These geochemical characteristics align with those observed in the Zhunuo porphyry copper deposit but differ from tourmalines associated with lithium and beryllium mineralization in the leucogranites of the Gyirong and Cuona regions in southern Tibet. This indicates that the Daju area holds significant potential for the formation of porphyry copper deposits, warranting further exploration efforts.

Carbon-containing refractory gold ores present a significant technical challenge in the fields of mineral processing and metallurgy, primarily due to the impact of carbonaceous materials on gold leaching behavior. This paper provides a comprehensive review of the resource distribution, mineral structural characteristics, and adsorption mechanisms associated with carbonaceous materials in these ores. It emphasizes the exploration of the physical and chemical properties of carbonaceous materials and their interaction mechanisms with gold. The study reveals that factors such as specific surface area, pore structure, functional group composition, and degree of graphitization of carbonaceous materials have a substantial influence on the preg-robbing effect. The adsorption of elemental carbon is predominantly driven by physical adsorption, whereas humic substances interfere with gold leaching through chemical adsorption and complexation. In contrast, the impact of hydrocarbons on gold adsorption is found to be negligible. Furthermore, this paper examines the analytical capabilities of multi-scale characterization techniques in assessing the microscopic morphology, crystalline structure, and molecular composition of carbonaceous materials. It highlights the limitations inherent in single characterization techniques and underscores the necessity for the integration of multiple techniques to thoroughly analyze the structural characteristics of carbonaceous materials. This research offers significant theoretical foundations and serves as a reference for the efficient processing of carbon-containing refractory gold ores and the precise characterization of carbonaceous materials.

The Jinlongshan gold deposit in Xiushui County, Jiangxi Province, is situated within the central segment of the Jiangnan orogenic belt from a tectonic perspective. Regionally, it is positioned within the northeast-trending metallogenic belt extending from northeastern Hunan to northwestern Jiangxi. This belt includes the Huangjindong and Wangu gold deposits and lies adjacent to the eastern extension of the Hunan “Golden Belt” towards Jiangxi Province. The area exhibits favorable geological conditions conducive to mineralization. However, the level of exploration conducted in the mining area remains relatively low. To effectively extract mineralization information and delineate target areas for mineral exploration, a 1∶10 000 scale soil geochemical survey was conducted, encompassing an area of 18 square kilometers. A total of 8 934 soil samples were collected and analyzed for the content of six elements: Au, Ag, Co, As, Sb, and W. The soil geochemical parameters indicate that the Au and As elements exhibit high enrichment coefficients and significant differentiation, identifying them as favorable elements for mineralization within the area. Elemental correlation analysis, cluster analysis, and factor analysis have delineated three distinct mineral element assemblages: the Au-As-Sb combination, the Ag-Co combination, and W. Among these, gold （Au） exhibits a strong correlation with arsenic（As） and antimony（Sb）, indicative of a medium- to low-temperature element assemblage. This correlation establishes gold as the primary ore-forming element within the mining area, while As and Sb serve as geochemical indicators for exploration. Based on the elemental concentrations and the characteristics of anomalous assemblages in the region, 42 comprehensive gold anomalies have been identified. Integrating these findings with the geological context and mineralization patterns of the area, four high-potential gold exploration target zones have been delineated: the Youkeng, Dankeng, Huashikeng, and Banshanli gold anomaly areas. Subsequent surface trenching and deep drilling have verified the presence of seven gold mineralization alteration zones and two gold ore bodies, characterized by structural alteration rock mineralization. The alteration zones and ore bodies are strategically located within significant comprehensive anomalies, demonstrating a high degree of correlation with these anomalies. Notably, the Huashikeng gold anomaly area exhibits substantial potential for gold prospecting, suggesting that the 1∶10 000 scale soil geochemical survey has yielded promising prospecting outcomes in the Jinlongshan gold deposit region.

Pyrrhotite is a prevalent gangue mineral found in non-ferrous sulfide ores, including those of copper, lead, and zinc. Its non-stoichiometric crystal structure, characterized by variable iron-to-sulfur(Fe/S) ratios, leads to complex crystal-chemical behavior. Additionally, the unstable bonding state at its surface makes it highly susceptible to oxidation when exposed to oxygen in the flotation pulp. These characteristics often impede the selective flotation separation of valuable minerals, presenting a significant challenge in the efficient recovery of non-ferrous metals. During the oxidation process, iron ions migrate from the bulk to the mineral surface, where they coordinate with O₂, OH⁻, and H₂O to form an outer layer of iron oxyhydroxide(FeOOH), while leaving behind an iron-depleted, sulfur-enriched sublayer. This process is influenced by the pulp’s pH and oxidation-reduction potential(Eh), leading to the progressive oxidation of monosulfide species within the sublayer to disulfides and polysulfides, thereby continuously altering the surface chemistry of pyrrhotite. Under mild oxidation conditions, surface metal-hydroxyl complexes are formed, which modify the surface charge and result in a positive zeta potential. In contrast, xanthate collectors are present in solution as negatively charged anions, which facilitates their electrostatic adsorption onto pyrrhotite. This interaction undermines the efficiency of depression and complicates the separation of pyrrhotite from target minerals. Under conditions of intensified oxidation, Fe(OH)₃ precipitates form on the mineral surface. The pronounced hydrophilic nature of Fe(OH)₃ results in the formation of a dense hydrophilic film, which markedly diminishes mineral floatability and significantly impedes the flotation of pyrrhotite. It is important to note that pyrrhotite primarily exists in two crystalline forms: non-magnetic hexagonal pyrrhotite and magnetic monoclinic pyrrhotite. The inherent crystallochemical differences between these forms result in distinct surface oxidation kinetics, surface electrical properties, and adsorption affinities for flotation reagents. Consequently, the two polymorphs exhibit differing flotation behaviors within the same flotation system, thereby substantially complicating the separation of valuable non-ferrous sulfide minerals. The detrimental impact of pyrrhotite on flotation separation is primarily exhibited through two mechanisms: (1)its oxidation process depletes dissolved oxygen(DO) in the pulp, which is crucial for the surface oxidation activation of target sulfide minerals during flotation;(2) galvanic interactions occur when pyrrhotite is in contact with other sulfides in the pulp, thereby modifying the surface chemistry of the associated minerals. In industrial applications, synergistic strategies can be implemented to selectively depress or activate pyrrhotite flotation. These strategies include controlling its oxidation rate by adjusting pH levels or adding antioxidants, regulating pulp DO through staged aeration or the use of redox modifiers, and modulating the electrochemical interactions between pyrrhotite and target sulfide minerals.

The lower Ku’erbin River gold deposit, presently in the explorationphase, represents a newly identified epithermal gold deposit within the northern Lesser Khingan Range. The gold orebodies, or mineralization, are predominantly hosted within the Lower Cretaceous Ganhe Formation andesites, marking the inaugural discovery of gold mineralization in this region. To systematically investigate the relationship between the host rocks and gold mineralization, comprehensive field geological surveys, petrological analyses, zircon U-Pb geochronology, and petrogeochemical studies were undertaken. LA-ICP-MS zircon U-Pb dating indicates that the andesites hosting the ore were formed at (106.4±1.0)Ma(MSWD=1.8) during the late Early Cretaceous. Petrogeochemical and zircon Hf isotopic analyses reveal that the Ganhe Formation andesites in the lower Ku’erbin River gold district are characterized as magnesian andesites of the low-iron calc-alkaline series. These andesites exhibit high MgO contents(2.55%~4.72%), elevated Mg^# values(48~64), and low TFeO/MgO ratios(1.01~1.95), indicating formation in an active continental margin tectonic setting. Their genesis is attributed to stagnant slab melting, primarily influenced by subducted sediment melts with additional contributions from subduction-related fluids. The magma experienced interactions within the shallow mantle and crust-mantle mixing during its ascent, exemplifying the synergistic coupling of multi-stage geological processes. Zircon Ce-U-Ti oxybarometry analysis indicates that the volcanic rocks of the Ganhe Formation in the mining area exhibit ΔFMQ values ranging from 0.13 to 2.85, with an average of 0.94, suggesting moderately high oxygen fugacity. Furthermore, the zircon Ti temperatures are relatively elevated, averaging 820 ℃, which is likely associated with the prolonged replenishment of the magmatic system. A comprehensive analysis suggests that the Ganhe Formation volcanic rocks possess significant gold mineralization potential, providing a crucial scientific foundation for future regional exploration efforts.

To address the technical challenges associated with the design and construction of large-section single tunnels in water-rich basalt with tuff strata, such as the determination of construction methods and support parameters, a comprehensive study was conducted. This study was based on a new high-speed railway tunnel project in Yunnan Province and employed engineering investigation, field monitoring, and numerical simulation to examine the deformation and control technology of the surrounding rock. The results indicate the following：（1）Implementing initial support immediately after excavating the upper bench using the two-bench method significantly reduces the crown settlement rate, achieving a final settlement of approximately 38.5 mm, thereby effectively limiting further deformation of the arch base.（2）During excavation, horizontal deformation is concentrated at the arch foot and waist. After excavation, the maximum horizontal displacement shifts downward to the arch wall, with the affected area expanding outward in a butterfly-like pattern. In the two-bench method, the monitoring points at the upper and middle benches exhibit greater clearance convergence values and rates compared to the three-bench method, whereas the lower bench shows smaller values. Additionally, the rapid closure of the invert in the two-bench method results in superior deformation control.（3）Tunneling through strata with high water content creates a dewatering funnel, where groundwater seeps out along the tunnel face and benches. The two-bench method reduces the initial support closure time, leading to decreased dewatering. However, it results in the formation of a high-pressure zone above the crown.（4）The installation of additional drainage pipes can mitigate the load on the lining structure. Furthermore, the integration of mechanized construction techniques with the two-bench method has approximately doubled the average monthly construction progress.

In the context of the “dual carbon” objective, the vertical integration of the energy metal industry chain has emerged as a crucial strategy for facilitating energy transformation. This study adopts a configurational perspective, employing the “Technology-Organization-Environment”(TOE) theoretical framework, alongside necessary condition analysis (NCA) and fuzzy set qualitative comparative analysis(fsQCA) methods, to systematically investigate the driving mechanisms behind vertical integration within the energy metal industry chain. The research findings indicate that: (1)Vertical integration results from the synergistic interaction of multiple factors, with technical, organizational, and environmental factors not being individually necessary conditions; (2)The backward integration of new energy enterprises follows two configuration paths: a single core-driven supply chain stability and a dual core-driven revenue supply chain stability; (3)The forward integration of non-ferrous metal enterprises is characterized by two modes: technology supply chain synergy-driven and technology-revenue-environment comprehensive driven approaches.The study reveals the distinct driving mechanisms of vertical integration employed by enterprises at various stages of the industry chain, offering both a theoretical foundation and practical insights for optimizing the configuration of the energy metal industry chain. The research indicates that enterprises should select an integration strategy aligned with their specific resource endowments, while governmental bodies should develop tailored industrial policies to facilitate the coordinated development of the industry chain.

The Saibagou region is situated in the eastern segment of the tectonic belt along the northern margin of the Qaidam Basin. Within this area, a series of gold deposits have developed along the NNW-oriented ductile shear belt and its subsidiary faults. This study conducted in situ sulfur isotope and trace element analyses of pyrite from the primary ore-forming stages of the Gashun, Tuoxingou, and Wudarehu gold deposits, building upon comprehensive field geological investigations and mineralogical studies. The findings reveal that the sulfur isotopes of the gold deposits in the Saibagou area exhibit a relatively concentrated tower-type distribution, with an average range of -1.55‰ to 3.93‰. This distribution suggests characteristics indicative of both mantle-derived and granite-derived sulfur, aligning closely with the sulfur isotope composition typical of orogenic gold deposits located along the northern margin of the Qaidam Basin. The overall composition is enriched with arsenic （As）, cobalt （Co）, nickel （Ni）, and selenium （Se）, while the relative concent rations of gold （Au）, silver （Ag）, copper （Cu）, lead （Pb）, zinc （Zn）, and bismuth （Bi） are notably high. A significant correlation is observed between Au and As. Gold predominantly occurs within the pyrite lattice as a solid solution, whereas copper primarily associates with pyrite as independent elements rather than substituting for iron （Fe）. The ore-forming fluid is characterized by a relatively reductive environment. Through a comprehensive analysis encompassing ore-controlling structures, alteration types, mineral associations, host rock characteristics, trace element geochemistry, and sulfur isotope data, the gold deposit in the Saibagou area is classified as an orogenic gold deposit.

The Phapon gold deposit in Laos is situated within the northern segment of the Luang Prabang-Loei metallogenic belt. This deposit is distinguished by the spatial coexistence of hydrothermal gold ore bodies, which include coarse-grained calcite veins and orpiment-realgar quartz-calcite veins, alongside palaeokarst cave-hosted sedimentary-accumulated high-grade gold ore pod. Recently, a newly identified high-grade gold ore body, averaging 40.18×10^-6 Au, has been discovered within that ore pod. This body is hosted by palaeokarst cave conglomerates and formed through sedimentary re-enrichment processes. Investigations into the occurrence of gold reveal that the interbedded sandstone and conglomerate are enriched with visible native gold. Larger gold particles, predominantly ranging from 2~10 μm, are located within the pores of detrital grains and exhibit slightly rounded but predominantly uneven edges with impact pits. In contrast, smaller particles, less than 1 μm in size, are embedded within clay and ferruginous mineral matrices and display relatively regular shapes. Comprehensive research on the source-to-sink mechanisms of gold suggests that the calcite-rich hydrothermal gold veins may have served as the source for the palaeokarst cave conglomerate-hosted ore bodies. The karst cave associated with the F₁ palaeokarst unconformity created an advantageous environment for mineralization. The relatively coarse native gold originating from hydrothermal veins underwent reworking through karst processes, followed by mechanical transportation and sorting via surface runoff, ultimately leading to its deposition within the sand and gravel pores, resulting in the formation of larger gold particles （2~10 μm）. Additionally, some primary gold may have experienced remobilization and migration, subsequently undergoing adsorption and reprecipitation on the surfaces of clay and ferruginous minerals, thereby forming smaller gold particles （<1 μm）. The recent identification of a palaeokarst cave conglomerate-hosted high-grade gold ore body marks a significant advancement from the previous exploration paradigm, which concentrated exclusively on hydrothermal gold veins. Paleo-caves and other favorable karst landforms situated along the F₁ paleokarst unconformity present substantial potential for accommodating large-scale karst sedimentary-accumulated type rich ore deposits.

The Lannigou gold deposit represents a quintessential“fault-controlled” large carlin-type gold deposit located within the “Golden Triangle”region encompassing Yunnan, Guizhou, and Guangxi. The gold ore body is stringently regulated by the fault zone.Previous research has extensively explored the relationship between the structural features and mineralization processes of the Lannigou gold deposit, yielding significant findings. However, recent years have witnessed a stagnation in exploration activities, adversely impacting the subsequent production and development of the mines. Consequently, there is a pressing need to reorganize the latest exploration data, further elucidate the structural control mechanisms governing the Lannigou gold deposit, and inform the strategic planning of future prospecting endeavors. This study employs the theoretical framework and methodologies of structural analysis of ore fields, leveraging the most recent exploration data to reconstruct the structural evolution of the Lannigou gold deposit. The investigation re-identifies the primary ore-controlling structures, synthesizes the principles of tectonic ore control, and delineates prospective target areas for exploration based on these tectonic ore-controlling principles. The findings indicate that the tectonic features within the Lannigou gold deposit area can be categorized into four distinct stages. During the D1 stage, extensional forces resulted in the formation of horizontal folds or folds with axial planes inclined towards the southwest, characterized by a gentle inclination of the axial plane. In the D2 stage, the region experienced NE-SW compressional forces, leading to the development of vertical or acute-angle folds with NE-SW oriented axial planes, alongside the F₃ fault system. This stage reworked the folds formed in the D1 stage and marks the period of significant thrust nappe structure formation in the area. The D3 stage was characterized by NW-SE compressional forces, which reactivated existing faults and resulted in the formation of a series of minor thrust faults. Subsequently, during the D4 stage, N-NE oriented normal faults emerged, leading to minor-scale reconstruction of earlier fold and fault systems. Mineralization is predominantly associated with the reactivation of preexisting faults induced by the compressional forces of the D3 stage. The primary ore-controlling structure is the thrust nappe system, with the F₇ fault serving as the principal ore-guiding structure, while the F₃ fault functions as a secondary ore-bearing structure. This work not only provides a concrete basis for the further exploration of the Lannigou gold deposit, but also provides a typical example for the analysis of the carlin-type gold ore-controlling structure in the Yunnan, Guizhou and Guangxi areas.

The Xijiele research area is situated in the southern region of Qinghe County, within Altay Prefecture, Xinjiang. This area exhibits a complex geological structure, characterized by the presence of basic volcanic and clastic rock formations within the Late Paleozoic island arc zone. This study utilizes 1∶10 000 soil geochemical measurement data to evaluate the relative merits and drawbacks of conventional anomaly delineation techniques versus lithological zoning anomaly lower limit lining methods. The findings reveal that traditional approaches, which apply a uniform lower limit for anomalies across the entire region, are vulnerable to interference from areas with high background levels, resulting in the potential oversight of false or weak anomalies. In contrast, the lithological zoning anomaly lower limit lining method enhances the precision of anomaly identification by categorizing sedimentary, volcanic, and intrusive rocks into three distinct sub-zones, calculating lining values, and normalizing them accordingly. The validation of established gold （Au） and copper （Cu） mineral deposits within the region indicates that the anomalies identified through the lithological zoning method not only demonstrate a higher degree of concordance with the spatial distribution of the mineral deposits but also exhibit more distinct concentration zoning characteristics. Furthermore, their spatial distribution patterns show improved correlation with the regional geological background of mineralization. This method effectively enhances the contrast between anomalies and background by mitigating the influence of lithological background variations, thereby offering a novel technical approach for the identification of geochemical anomalies in areas with complex lithological distributions. It holds significant practical value for guiding mineral exploration efforts in regions with analogous geological backgrounds.

The geochemical survey, recognized as a direct and efficient method for geochemical prospecting, is characterized by a well-established workflow and proven effectiveness in mineral exploration. The Heishantou area, located within the southern belt of the Beishan region in Gansu Province, is part of the Beishan denudation Gobi zone's geochemical landscape. Within this study area, sixteen composite anomalies were identified through a stream sediment survey conducted at a 1∶50 000 scale. To further refine these anomalies, investigate their underlying causes, and achieve significant breakthroughs in prospecting, the AS-13 anomaly was selected for a more detailed lithochemical geochemical survey at a 1∶10 000 scale. This surface sampling involved the collection of rock fragments or lithic debris ranging from 2 to 20 mm in size, utilizing sampling media that included weathered bedrock fragments, fault breccias, and altered lithic debris exhibiting significant mineralization. A comprehensive analysis was conducted on eleven elements, namely Au, Ag, Cu, Pb, Zn, W, Sn, Mo, As, Bi and Sb. Employing correlation analysis and R-type cluster analysis, the characteristics of element associations were examined and synthesized. Preliminary findings suggest that the regional element associations are characterized by: 1) Au, As, Cu, and Zn, indicative of the mineralization phase; and 2) W, Mo, Pb, and Ag, which are reflective of early-stage complex hydrothermal activity. The results reveal that anomalies of elements such as Au, As, Cu, and Mo within the study area exhibit strong spatial coherence, high intensity, distinct enrichment centers, and considerable potential for mineral exploration. Based on the element association characteristics and the geological framework, the anomalies are predominantly aligned along the NW-trending ductile shear zone. Verification through trenching exploration at the composite anomaly AR-5 identified five gold-mineralized bodies. These ore bodies have lengths ranging from 75 to 185 meters, thicknesses from 0.45 to 1.10 meters, and gold grades between 1.09×10^-6 and 15.6×10^-6. The ore type is classified as quartz vein-type. The gold mineralized bodies are located within a ductile shear zone and are closely associated with mineralization-alteration processes such as silicification, arsenopyritization, hematitization, and jarositization. By comparing the regional characteristics, geochemical signatures, orebody features, wall-rock alteration, and ore-controlling factors of typical gold deposits within this ductile shear zone, it is inferred that the Heishantou area holds significant potential for the formation of ductile shear zone-type gold deposits, with promising prospects for exploration. Our study concludes that the 1∶10 000 scale lithogeochemical survey has proven highly effective in verifying anomalies within the denuded Gobi regions of the Beishan area. This method facilitates rapid anomaly targeting and serves as a valuable complement to soil geochemical surveys, demonstrating strong prospecting efficiency in the denuded Gobi regions of the Beishan area in Gansu Province. This approach provides valuable references for geological prospecting in similar landscape regions.

The Matigou-Miaogou gold deposit, situated in Fengxian, Shaanxi Province, within the West Qinling region of China, is positioned at the southern margin of the western Shangdan fault zone, centrally located in the Qinling orogenic belt. This deposit represents a quintessential example within Shaanxi Province’s recent strategic initiatives aimed at advancing ore prospecting breakthroughs. The geological strata in this region span from the Paleoproterozoic to the Quaternary periods. Owing to multiple episodes of rifting, contraction, and amalgamation since the Proterozoic era, the exposed strata have experienced varying degrees of deformation, resulting in the formation of near east-west trending complex folds and faults. During the Triassic period, the region experienced intense magmatic activity, characterized by frequent magma intrusions that were often accompanied by multi-stage mineralization. Consequently, this area constitutes a significant structural zone for gold and nonferrous polymetallic mineralization. Notably, the diorite-porphyrite distribution within the mine area is extensive, with evident mineralization and alteration phenomena observable in certain sections, which are spatially closely associated with the ore bodies. This study conducts a preliminary investigation into the metallogenic epoch and mechanisms of the Miaogou gold deposit through a comprehensive analysis of the regional metallogenic background, geological characteristics, rare earth and trace element compositions of rocks (ores), H-O-S isotopic data, and zircon U-Pb dating of diorite-porphyrite veins in the Miaogou gold mine area. In this region, the diorite porphyrite exhibits total rare earth element (ΣREE) concent rations ranging from 99.45×10⁻⁶ to 121.44×10⁻⁶, with light rare earth element (LREE) concent rations between 90.60×10⁻⁶ and 112.26×10⁻⁶, and heavy rare earth element (HREE) concent rations from 8.85×10⁻⁶ to 10.12×10⁻⁶. The europium anomaly (δEu) values range from 0.91×10⁻⁶ to 0.99×10⁻⁶, while the cerium anomaly (δCe) values range from 0.93×10⁻⁶ to 0.94×10⁻⁶. For the ore samples, ΣREE content varies between 46.88×10⁻⁶ and 121.44×10⁻⁶, LREE content ranges from 41.60×10⁻⁶ to 184.34×10⁻⁶, and HREE content spans from 5.28×10⁻⁶ to 21.17×10⁻⁶. The δEu values for the ores range from 0.57×10⁻⁶ to 1.49×10⁻⁶, and δCe value s range from 0.85×10⁻⁶ to 0.98×10⁻⁶. Additionally, the δD_V-SMOW values range from -96‰ to -59‰, and the δ ¹⁸ Ofluid values range from 7.3‰ to 10.3‰, and the value of δ ³⁴S is from 4.15‰ to 11.88‰. The zircon U-Pb concordant age of the diorite porphyrite is determined to be (220.7±1.0)Ma, with a weighted average age of (219.8±2.1)Ma. The findings indicate that the majority of the metallogenic materials at the Miaogou gold mine are derived from magmatic sources, with a minor contribution from the surrounding rock strata. The metallogenic fluids are of multiple origins, predominantly consisting of magmatic water. It is posited that the Miaogou gold mine was formed during the Late Triassic period. During this epoch, significant brittle-ductile shear deformation and magmatic activity were intimately associated with gold mineralization and alteration processes. These geological phenomena likely provided the necessary thermal energy and mineral sources, facilitating the activation, migration, and enrichment of siliceous materials and minerals within the early Paleozoic Luohansi rock group. These materials subsequently concentrated within the multi-fissures oriented in the west-north-east-south direction, associated with brittle-ductile shear deformation. The tectonic deformation, magmatic activity, and ore-forming enrichment events of the Late Indosinian period hold substantial significance. The Miaogou gold deposit is thus interpreted as a product of extensive and intense deformation, metamorphic-magmatic activity, and fluid interactions governed by the brittle-ductile shear zones during the Late Triassic.

The Qibaoshan deposit, situated within the Qin-Hang metallogenic belt in eastern China, exemplifies a typical cobalt-bearing polymetallic deposit. Currently, its metallogenic mechanism remains inadequately elucidated, primarily due to the absence of systematic investigations into the mineralogical characteristics of pyrite, the primary cobalt-hosting mineral. This deficiency has significantly impeded a comprehensive understanding of the deposit’s genesis and ore-forming processes. In this study, we employ integrated petrographic, mineralogical, and geochemical analyses to delineate the ore-forming stages, systematically characterize the trace-element composition of pyrite, and subsequently discuss the metallogenic mechanism of the deposit. Microscopic examination of the ore reveals that pyrite in the Qibaoshan deposit can be categorized into two episodes and five stages: PyⅠ formed during the sedimentation-diagenesis stage of the first episode, manifesting in fractures of gangue minerals as diagenetic pyrite, while PyⅡ to PyV are products of the second episode of magmatic hydrothermal activity. PyⅡ is predominantly associated with arsenopyrite, while PyⅢ is linked to an abundance of cobalt-nickel minerals. PyⅣ serves as a primary mineral component in sulfide veins, and PyⅤ is found within carbonate veins. The δ ³⁴S values of pyrite range from 1.24‰ to 2.10‰. Integrating these findings with prior research, it is inferred that the ore-forming materials predominantly originated from magmatic sources and seawater sulfate. The major and trace element characteristics of pyrite provide a comprehensive record of the diagenetic-hydrothermal evolution process. Specifically, PyⅠ and PyⅡ display sedimentary origins（Co/Ni<1）, whereas the subsequent PyⅢ and PyⅣ exhibit hydrothermal characteristics（Co/Ni>1，S/Se<1×10⁵）. The concent rations of arsenic and selenium progressively increase from stageⅡ to stageⅣ, indicating a transition in the ore-forming fluid temperature from an initial high temperature to a medium-low temperature. The high nickel content（average 159×10^-6） in pyrite, along with the presence of lamprophyres and diabase in the region and the sulfur isotope data of pyrite, suggests that the ore-forming materials may have been derived from basic rocks. A thorough analysis reveals that the deposit experienced sedimentation and diagenesis, during the Late Paleozoic era, followed by alteration due to magmatic hydrothermal fluids, and several phases of mineral enrichment. The spatial emplacement of the deposit was influenced byregional unconformities and fault systems. The findings of this study enhance the understanding of the metallogenic processes associated with hydrothermal cobalt deposits and offer a scientific foundation for cobalt resource exploration within the Qin-Hang metallogenic belt.

Energy consumption in comminution processes, which include blasting, crushing, and grinding, constitutes a significant portion of operational costs in hard-rock mining. Traditional optimization approaches often treat blasting and crushing as separate systems, leading to inefficient energy distribution and underutilization of chemical energy （explosives） to alleviate the burden on downstream mechanical comminution.This study addresses this gap by developing a quantitative energy coupling model that connects blasting energy input, rock fragmentation distribution, and subsequent crushing energy consumption. To quantify these relationships, a comprehensive experimental program was conducted on two representative rock types：granodiorite porphyry and skarn.The methodology integrates dynamic impact tests using a Split Hopkinson Pressure Bar （SHPB） with static-impact crushing tests employing a drop-weight apparatus.The SHPB tests, conducted under varying impact air pressures, simulated the rock fracturing process under explosive loading.The results indicate a clear linear dependency, wherein the three-dimensional mean particle size of the blasted rock decreases proportionally with increasing incident energy. Subsequent to the primary stage, drop-weight tests were conducted on oversized fragments to establish an exponential growth model for crushing energy consumption as a function of input particle size. This model underscores the substantial energy costs associated with processing coarse blast fragmentation.By mathematically integrating both stages, the study developed a comprehensive model of total energy consumption. The analysis reveals that the total system energy exhibits a characteristic “U-shaped” trend （decreasing then increasing） within the constraints of the process.Specifically, an increase in blasting energy initially leads to a significant reduction in mechanical crushing load. However, beyond a certain point, further increases in blasting energy result in diminishing returns.The model identifies precise optimal operating points, with minimum total energy consumption recorded at 176.66 J for porphyry and 91.54 J for skarn.These minima correspond to an optimal fragment size range of 37~42 mm.By targeting this specific fragmentation range, overall system energy consumption can be reduced by up to 42.8% compared to conventional operational parameters.These findings reveal a fundamental conflict between the nonlinear characteristics of crushing dissipation and the gradient distribution of blasting energy. The results indicate that relying exclusively on mechanical crushing for size reduction is energetically inefficient for hard rocks. Instead, increasing the proportion of rock breakage achieved through chemical energy or implementing multi-stage crushing strategies can substantially improve system performance.This study, for the first time, develops a closed-loop quantitative coupling model of blasting energy, fragment size, and crushing energy. It elucidates the nonlinear principles governing inter-process energy transfer and provides both a theoretical foundation and parameterized guidance for optimizing energy use throughout the entire process. This research offers significant engineering value for cost-effective and sustainable energy-efficient hard-rock mining.

The Huangjindong gold field, situated in the northeastern region of Hunan Province within the Jiangnan Orogen, represents a major gold production site，boasting cumulative proven resources of approximately 80 tonnes with an average grade of 5 g/t.The ore bodies are predominantly hosted within interlayer shear fractures that have developed along the limbs of overturned folds trending from northwest-west to east-west.Despite its economic significance，a comprehensive understanding of the ore-controlling structural architecture has been lacking.Historically, the absence of a systematic analysis of the structural framework and deformation styles has impeded both a profound understanding of metallogenic regularity and the scientific planning of exploration initiatives in this field.To address this deficiency，this study conducts a detailed structural analysis grounded in extensive, fine-scale route mapping and field-based structural observations.The primary objectives were to （1） delineate the fold architecture and characterize the deformation patterns that govern mineralization, （2） elucidate the formation mechanisms of the predominant structures, and （3） explore the implications for future gold exploration endeavors. Our findings reveal a structural framework characterized by two primary elements: a system of NWW- to E-W-oriented folds and a series of NE-oriented faults. A notable structural divergence is evident across the regional Niwan Fault.To the west of this fault, the fold system consists of overturned anticline-syncline pairs with NWW-trending hinges and axial planes consistently dipping towards the NNE. Conversely, the eastern block exhibits folds with E-W-oriented hinges and north-dipping axial planes, suggesting a significant counterclockwise deflection of structural trends in the footwall compared to the hanging wall. We propose that the initial development of this fold system was governed by a critical layer-parallel décollement horizon located between the Xiaomuping and Huanghudong formations.Under a regional NNE-SSW compressional tectonic regime, this décollement facilitated detachment and slip, resulting in the formation of fault-propagation folds at its leading edge. We hypothesize that the observed deflection across the Niwan Fault was induced by subsequent northward thrusting along a concealed, approximately E-W-striking reverse fault. The fault in question likely originates from the Caledonian orogeny, and its movement has resulted in the differential rotation of the footwall block. The structural model developed in this study has significant implications for exploration.Future research should focus on: （1） systematically investigating the ore-hosting potential of interlayer shear fractures that have developed along the limbs of the identified folds, as these serve as primary fluid conduits and sites of mineral deposition; （2） considering the vertical segmentation and enrichment characteristics of ore shoots within these structures; （3） revising traditional exploration strategies that assumed a straightforward correlation of ore veins across the Niwan Fault; and （4） improving the targeting of intersections between the northeast-trending fault system and the northwest-west to east-west interlayer shear fractures, as these junctions likely functioned as high-permeability zones conducive to fluid concentration and enhanced gold deposition. This refined structural framework offers a robust foundation for future evidence-based exploration in the Huangjindong gold field and similar structurally controlled regions.

To investigate the influence of cellulose ether on the fluidity and compressive strength of classified tailings cemented backfill （CTCB）, hydroxypropyl methyl cellulose （in concentrations ranging from 0.1% to 0.3%） was utilized as a cellulose ether admixture. The variations in fluidity and strength of CTCB, both with and without cellulose ethers, were quantitatively assessed through rheological, expansion, bleeding, and unconfined compressive strength tests. Furthermore, the differences in microstructures of CTCB and the mechanism underlying cellulose ether-modified CTCB were investigated using chemical bonding water tests, scanning electron microscopy（SEM）, and mercury intrusion porosimetry（MIP）. The findings indicate that, compared to CTCB slurry without cellulose ether, at a concentration of 72%, an ash-to-sand ratio of 1∶4, and a cellulose ether content of 0.3%, the yield stress and plastic viscosity of the slurry increased by factors of 62.66 and 8.55, respectively, while the bleeding rate was completely eliminated.The addition of cellulose ethers to CTCB slurry results in increased yield stress and plastic viscosity, while simultaneously reducing the bleeding rate and enhancing the stability of the slurry.The effects become more pronounced with higher dosages of cellulose ethers. Notably, the expansion of the CTCB slurry decreases by 49.18%, indicating a negative correlation between cellulose ether dosage and slurry expansion, which suggests an adverse impact on the fluidity of the CTCB slurry.Furthermore, cellulose ethers exhibit an inhibitory effect on both the early （3 day） and long-term （28 day） compressive strength of CTCB. Specifically, when the cellulose ether content is increased from 0 to 0.3%, the 3-day compressive strength decreases by 49.44%, and the 28-day compressive strength decreases by 41.17%. The reduction in compressive strength becomes more significant with higher dosages of cellulose ethers. Scanning electron microscopy （SEM） analysis indicates that the incorporation of cellulose ethers does not alter the type of hydration products formed by the cementitious powders. The findings from the chemical binding water test suggest that incorporating cellulose ethers leads to a reduction in the content of hydration products. Observations utilizing mercury intrusion porosimetry （MIP） demonstrate that cellulose ethers introduce air, which subsequently increases the macropore content and overall porosity of the backfill. This results in suboptimal densification of CTCB. These research outcomes offer a valuable reference for the application of cellulose ethers in the modification of CTCB.

The Bailincheng Zn-polymetallic deposit is situated within the northern section of the Mesozoic tectono-magmatic-metallogenic belt of the Taihang Mountains, specifically in the eastern region of the Dahenan granitoid pluton. This study employs electron probe microanalysis(EPMA) to determine the major elements compositions of Pyrite and sphalerite, laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) for trace elements, and in-situ sulfur isotope analysis to elucidate the ore-forming environment, genetic type of the deposit, and the source of ore-forming materials. The orebodies of the Bailincheng Zn-polymetallic deposit occur in subtabular to lenticular forms, aligned with the structural belt, and are hosted within limestone. The findings reveal that Pyrite is characterized by an average sulfur content of 53.51% and iron content of 46.96%, indicating a slight enrichment in Fe and depletion in S compared to theoretical values(S=53.45%, Fe=46.55%), which suggests a Fe-rich, S-deficient nature. Additionally, δFe/δS-As and As-Co-Ni discrimination diagrams suggest a magmatic–hydrothermal origin. The Fe/(S+As) ratio in Pyrite exhibits a strong correlation with the mineralization position(r=0.878). In the Bailincheng deposit, Pyrite displays Fe/(S+As) values ranging from 0.857 to 0.902, with an average value of 0.877, suggesting formation in a shallow environment. The Co/Ni ratios in Pyrite range from 2.9 to 277.2, with Py-1(associated with early-formed oxide minerals) averaging 30.7 and Py-2(associated with late-stage sphalerite) averaging 131.5. Both Py-1 and Py-2 exhibit Co/Ni ratios greater than 1, indicative of hydrothermal Pyrite. Sphalerite displays Zn/Fe ratios ranging from 76.69 to 84.97 (average 80.46) and Zn/Cd ratios from 320 to 419 (average 377.16), which are characteristic of a medium-temperature hydrothermal deposit. Furthermore, the ln(Ga)/ln(In) ratios in sphalerite suggest affinities with skarn-type deposits. The δ ³⁴S values of Pyrite range from 5.47‰ to 8.88‰, with an average of 6.7‰. Compared to surrounding deposits, Pyrite from Bailincheng exhibits more positive δ ³⁴S values, indicating that the sulfur in the ore-forming fluids was primarily derived from magmatic-hydrothermal sources, with minor contributions from strata-derived sulfur. Pyrite is identified as the principal gold-bearing phase, with arsenic and gold showing a positive correlation, suggesting that gold primarily occurs as lattice-bound ionic gold within the Pyrite. In summary, the Bailincheng Zn-polymetallic deposit in the northern Taihang Mountains is characterized by skarn-type mineralization, and represents a medium-temperature magmatic-hydrothermal deposit formed in a shallow environment.