International Journal of Mining Science and Technology最新文献

{"title":"Anisotropy of laser-induced electro-response in shale: Modelling and experimental validation","authors":"Xuecong Liu,&nbsp;Zhengchun Hong,&nbsp;Yuqi Jiao,&nbsp;Kun Zhao,&nbsp;Xinyang Miao","doi":"10.1016/j.ijmst.2025.08.015","DOIUrl":"10.1016/j.ijmst.2025.08.015","url":null,"abstract":"<div><div>Laser-induced electro-response (LIER), as a new method that complements conventional rock physics testing techniques, is expected to address issues such as of unclear mechanisms, model deficiency, inconsistent evaluation parameters, and difficulty in separating multiple coupling factors in shale anisotropy evaluation, and establish a more complete and reliable shale physical property evaluation system. A testing strategy for out of plane anisotropy (OPA) was proposed for characterising anisotropy by LIER, where the near infrared (NIR) continuous laser (CL) and nanosecond pulsed laser (PL) were used to irradiate the surface of oblique cut shale, and the transverse LIER of the surface was measured. A LIER detection model is constructed from the laser-thermal effect, residual transverse polarization electric field and thermionic emission transport mechanism, which is strongly relying on laser power, bias voltage, and inclination angle of the measurement direction relative to the bedding plane of shale. For OPA test on the slice of oblique cut shale under CL irradiation, the relationship between the product of LIER simulation parameters and the tilting angle can be described by a cubic function and an impulse function with a maximum value at the threshold angle. In addition, the thermal accumulation and transient thermal effects are induced in the shale under a high-energy short laser pulse irradiation, and the simulation results indicate that there is an exponential relationship between the product of parameters in the LIER model and the tilt angle. Thus, for OPA test under CL and PL irradiations, it is recommended to use the product of parameters as an evaluation index for shale anisotropy. Furthermore, to solve the problem of multiple influencing factors entangled in the exponential term of the LIER model, the tangential LIER measurement was performed on the side of cylindrical shale core, where the provided LIER model effectively presented the anisotropy of tight shale plug, especially the effects of bias voltage and laser power on LIER were relatively separated as independent variables. Finally, the LIER at the end of laser drilling is presented well using the optimized model under a focused ns NIR PL irradiation, indicating that LIER is expected to be a real-time means for characterizing shale anisotropy during laser drilling processes. These results show that the present work is fundamental for the precise evaluation and effective development of anisotropic shale reservoirs, and will drive the advances of LIER in the exploration for shale oil and gas.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1663-1676"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145404935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reverse floc-flotation of talc from chalcopyrite by using polyvinyl acetate as a flocculant: Adsorption and bubble capture studies","authors":"Yu Xie ,&nbsp;Wanzhong Yin ,&nbsp;Qi Liu ,&nbsp;Daowei Wang ,&nbsp;Wenju Sun","doi":"10.1016/j.ijmst.2025.08.016","DOIUrl":"10.1016/j.ijmst.2025.08.016","url":null,"abstract":"<div><div>Chalcopyrite is often intergrown with talc, which, after grinding, forms ultrafine particles (&lt;10 μm) that readily coat chalcopyrite surfaces, hindering flotation and causing significant losses in tailings. This study evaluates polyvinyl acetate (PVAc), a thermoplastic polymer, as a selective flocculant to enhance reverse flot ation separation of chalcopyrite from ultrafine talc. Flotation tests showed that at a PVAc dosage of 40  mg/L, talc can be effectively and selectively removed, enabling efficient separation. Laser particle size analysis and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) confirmed that PVAc promotes selective talc aggregation without affecting chalcopyrite. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that hydrogen bonding between PVAc ester groups and surface hydroxyls on talc drives the flocculation, while chalcopyrite lacks suitable binding sites. PVAc adsorption also enhances talc hydrophobicity. Furthermore, particle-bubble coverage angle measurements and extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory theoretical calculations demonstrated that PVAc-induced flocculation increases attractive interactions between talc and bubbles, shifting the total interaction energy from repulsive to attractive and promoting bubble-particle attachment. This study clarifies the selective adsorption and flocculation mechanisms of PVAc and reveals the coupling of flocculation and flotation of ultrafine talc from a particle-bubble capture perspective, while expanding the potential of ester-based polymers for ultrafine mineral recovery.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1775-1788"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145404936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A nonlinear hydraulic fracture propagation criterion considering the fracture process zone","authors":"Senlin Luo ,&nbsp;Guangqing Zhang ,&nbsp;Yansen Ling ,&nbsp;Jinmiao Tan ,&nbsp;Renyi Qiu ,&nbsp;Bin Sun","doi":"10.1016/j.ijmst.2025.09.007","DOIUrl":"10.1016/j.ijmst.2025.09.007","url":null,"abstract":"<div><div>The linear elastic hydraulic fracture criterion is not applicable to deep reservoirs when nonlinear behavior is present over an extensive zone at the fracture tip. This study aims to develop a criterion for nonlinear hydraulic fracture considering the fracture process zone (FPZ) and seeks to reveal the causes of nonlinearity during fracture propagation in deep reservoirs. A closing stress profile considering the in-situ stress was established by using the cohesive zone model (CZM) to describe the FPZ at the fracture tip. An analytical model for the FPZ length was derived, while the criterion for nonlinear fracture propagation was proposed. The FPZ fully developed and the fracture began to propagate when the apparent stress intensity at the fracture tip reached the apparent fracture toughness or when the in-situ stress intensity reached the in-situ fracture toughness. The proposed criterion can clearly determine the length of the FPZ, accurately predict the breakdown pressure during fracturing operations, and establish a relationship between these two parameters. It addresses the inherent limitations of conventional linear elastic fracture mechanics (LEFM), which often underestimates fracture toughness and neglects the effects of the FPZ. This research is expected to enhance the fracturing design in deep reservoirs.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1645-1662"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145382921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative characterization of fracture surface undulations and gas-guiding patterns in fractured rocks under steady loading","authors":"Zihan Chen ,&nbsp;Quanle Zou ,&nbsp;Feixiang Lv ,&nbsp;Qican Ran ,&nbsp;Xiaoyan Sun ,&nbsp;Xianwei Heng","doi":"10.1016/j.ijmst.2025.08.017","DOIUrl":"10.1016/j.ijmst.2025.08.017","url":null,"abstract":"<div><div>Fractures in rock strata serve as flow pathways for gas flow. The undulation of fracture channels can influence the guidance of gas flow. In this context, four-point bending experiments on prefabricated fractured rocks at different angles under stable stepped loading stress. The experiment results clarified the evolutionary law that the undulation degree of the rock tensile fracture surface is separated by an initial fracture angle of 45°. The high undulation intervals were less than 45°, whereas the low undulation intervals were more than 45°. Furthermore, the relative undulation degree, undulation frequency, and matching degree of the fracture surface were quantified. The relationship between the change in fracture surface undulation and gas flow guidance was established. Based on this, the stability, tortuosity, and uniformity of the gas flow in the fracture channel were quantitatively characterized. Subsequently, numerical models of the fracture channels were constructed to validate the indices proposed in this study. The results of the study clarified the influence of different initial fracture angles on the undulation changes of fracture surfaces, and established the relationship between these changes and gas flow, which is conducive to understanding the role of internal fracture channels in rocks in guiding the gas flow process.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1753-1773"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145555314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation of anisotropy ratio evolution in coal permeability: Implications for underground compressed air energy and CO2 storage","authors":"Tiancheng Zhang ,&nbsp;Luwei Ding ,&nbsp;Jimmy Xuekai Li ,&nbsp;Yiran Zhu ,&nbsp;Victor Rudolph ,&nbsp;Zhongwei Chen","doi":"10.1016/j.ijmst.2025.09.006","DOIUrl":"10.1016/j.ijmst.2025.09.006","url":null,"abstract":"<div><div>Reliable forecasting of coal seam gas production and gas injectivity (e.g., CO₂ or air) requires an accurate understanding of coal’s anisotropic permeability, which governs the directional flow of gas. Although the anisotropic nature of coal permeability is well recognized, little attention has been paid to how this ratio evolves with changes in effective stress or with the injection of gases that have different affinities to coal. In this work, more than 600 permeability tests were conducted on eight cubic Australian coal samples using He, N₂ and CO₂ gases under varying effective stresses, providing a comprehensive dataset that allows the combined effects of effective stress and gas adsorption on permeability anisotropy to be robustly assessed on the same samples. The results demonstrated that all coal samples exhibited evident permeability anisotropy, with ratios ranging from 1.11 to 6.55. For the first time, quantitative relationships between the anisotropy ratio, effective stress, and initial permeability were established for each of the three injection gases, highlighting how gas adsorption and effective stress changes both anisotropic permeability magnitude and ratio. These findings provide new insights into the directional flow behavior of gases in coal seams, with implications for underground compressed air energy storage and CO₂ sequestration.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1713-1729"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145382929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow behavior of a rough single rock fracture under high-temperature, high-stress, and high-seepage pressure coupling conditions","authors":"Bingqi Wang ,&nbsp;Wendong Yang ,&nbsp;Xiang Zhang ,&nbsp;Yongfei Yang ,&nbsp;Lei Zhang ,&nbsp;Jun Yao","doi":"10.1016/j.ijmst.2025.09.001","DOIUrl":"10.1016/j.ijmst.2025.09.001","url":null,"abstract":"<div><div>Understanding the complex flow behavior along a rough rock fracture under high-temperature, high-stress, and high-seepage pressure (HTHM) coupling conditions is of great significance for optimizing deep resource extraction. This study investigates the complex flow behavior of a single rock fracture under coupled HTHM conditions using a self-developed multi-field coupling experimental system, considering real-time high temperatures (20–90 °C), confining pressures (30–120 MPa), and seepage pressures (5–60 MPa). Experimental results show that as confining pressure increases, two typical nonlinear flow behaviors are observed, which are Forchheimer flow and low-velocity nonlinear flow. The increase in temperature and decrease in roughness significantly promote the fluid flow and enhance the nonlinear relationship between the volumetric flow rate and the hydraulic gradient at lower confining pressures (30 MPa). However, the change in temperature and fracture surface roughness does not affect the nonlinear type of fluid flow. Under a given hydraulic gradient, the influence of temperature and fracture roughness on the volumetric flow rate varies with changes in confining pressure. Additionally, this study considers both the viscous and inertial terms, and a modified Forchheimer equation is proposed using two parameters: the contact area ratio and the thermal expansion coefficient of the rock. The proposed model can effectively predict the nonlinear flow behavior of fluid along rough fractured rocks under varying temperatures and surface roughness. The experimental results and the proposed model provide valuable data and theoretical guidance for deep oil and gas exploration as well as hydraulic fracturing design.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1789-1807"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145555315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An interactive framework integrating segment anything model and structure-from-motion for three-dimensional discontinuity identification in rock masses","authors":"Jiawei Wang ,&nbsp;Jun Zheng ,&nbsp;Jie Hu ,&nbsp;Xiaojin Gong ,&nbsp;Qing Lü ,&nbsp;Ju Han ,&nbsp;Jialiang Sun","doi":"10.1016/j.ijmst.2025.09.005","DOIUrl":"10.1016/j.ijmst.2025.09.005","url":null,"abstract":"<div><div>The identification of rock mass discontinuities is critical for rock mass characterization. While high-resolution digital outcrop models (DOMs) are widely used, current digital methods struggle to generalize across diverse geological settings. Large-scale models (LSMs), with vast parameter spaces and extensive training datasets, excel in solving complex visual problems. This study explores the potential of using one such LSM, Segment anything model (SAM), to identify facet-type discontinuities across several outcrops via interactive prompting. The findings demonstrate that SAM effectively segments two-dimensional (2D) discontinuities, with its generalization capability validated on a dataset of 2426 identified discontinuities across 170 outcrops. The model achieves 0.78 mean IoU and 0.86 average precision using 11-point prompts. To extend to three dimensions (3D), a framework integrating SAM with Structure-from-Motion (SfM) was proposed. By utilizing the inherent but often overlooked relationship between image pixels and point clouds in SfM, the identification process was simplified and generalized across photogrammetric devices. Benchmark studies showed that the framework achieved 0.91 average precision, identifying 87 discontinuities in Dataset-3D. The results confirm its high precision and efficiency, making it a valuable tool for data annotation. The proposed method offers a practical solution for geological investigations.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 10","pages":"Pages 1695-1711"},"PeriodicalIF":13.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micromechanical properties of granite with insights into mineral interface mechanics","authors":"Pengli Zhou ,&nbsp;Cunbao Li ,&nbsp;Heping Xie","doi":"10.1016/j.ijmst.2025.08.009","DOIUrl":"10.1016/j.ijmst.2025.08.009","url":null,"abstract":"<div><div>Understanding the mechanical behavior of diagenetic mineral granules and interfaces in granite provides essential experimental references for constructing micromechanical models of granite. The micromechanical behavior of Yanshanian granite is investigated using scanning electron microscopy–energy dispersive spectroscopy (SEM-EDS) and nanoindentation tests. The results demonstrate transitional mechanical properties at mineral interfaces. The elastic modulus and hardness exhibit intermediate values between adjacent mineral phases. The higher plasticity indices at the interfaces suggest higher plastic deformation capacity of hard-phase minerals in these regions. Additionally, fracture toughness measurements of minerals and interfaces were obtained, with interfacial values ranging from 0.90 to 1.63 MPa·m^0.5. The analysis of mechanical property relationships shows a significant positive linear correlation between rock-scale elastic modulus and fracture toughness. However, this correlation is substantially lower at the mineral scale, demonstrating a scale effect in the relationship of different mechanical properties.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 9","pages":"Pages 1419-1437"},"PeriodicalIF":13.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145420429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fracturing mechanism of pre-damaged granite induced by multi-source dynamic disturbances in tunnels","authors":"Biao Wang,&nbsp;Benguo He,&nbsp;Xiating Feng,&nbsp;Hongpu Li","doi":"10.1016/j.ijmst.2025.08.001","DOIUrl":"10.1016/j.ijmst.2025.08.001","url":null,"abstract":"<div><div>To elucidate the fracturing mechanism of deep hard rock under complex disturbance environments, this study investigates the dynamic failure behavior of pre-damaged granite subjected to multi-source dynamic disturbances. Blasting vibration monitoring was conducted in a deep-buried drill-and-blast tunnel to characterize in-situ dynamic loading conditions. Subsequently, true triaxial compression tests incorporating multi-source disturbances were performed using a self-developed wide-low-frequency true triaxial system to simulate disturbance accumulation and damage evolution in granite. The results demonstrate that combined dynamic disturbances and unloading damage significantly accelerate strength degradation and trigger shear-slip failure along preferentially oriented blast-induced fractures, with strength reductions up to 16.7%. Layered failure was observed on the free surface of pre-damaged granite under biaxial loading, indicating a disturbance-induced fracture localization mechanism. Time–stress–fracture–energy coupling fields were constructed to reveal the spatiotemporal characteristics of fracture evolution. Critical precursor frequency bands (105–150, 185–225, and 300–325 kHz) were identified, which serve as diagnostic signatures of impending failure. A dynamic instability mechanism driven by multi-source disturbance superposition and pre-damage evolution was established. Furthermore, a grouting-based wave-absorption control strategy was proposed to mitigate deep dynamic disasters by attenuating disturbance amplitude and reducing excitation frequency.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 9","pages":"Pages 1439-1459"},"PeriodicalIF":13.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145420430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PFC-FDEM multi-scale cross-platform numerical simulation of thermal crack network evolution and SHTB dynamic mechanical response of rocks","authors":"Yue Zhai ,&nbsp;Shaoxu Hao ,&nbsp;Shi Liu ,&nbsp;Yu Jia","doi":"10.1016/j.ijmst.2025.08.013","DOIUrl":"10.1016/j.ijmst.2025.08.013","url":null,"abstract":"<div><div>Underground engineering in extreme environments necessitates understanding rock mechanical behavior under coupled high-temperature and dynamic loading conditions. This study presents an innovative multi-scale cross-platform PFC-FDEM coupling methodology that bridges microscopic thermal damage mechanisms with macroscopic dynamic fracture responses. The breakthrough coupling framework introduces: (1) bidirectional information transfer protocols enabling seamless integration between PFC’s particle-scale thermal damage characterization and FDEM’s continuum-scale fracture propagation, (2) multi-physics mapping algorithms that preserve crack network geometric invariants during scale transitions, and (3) cross-platform cohesive zone implementations for accurate SHTB dynamic loading simulation. The coupled approach reveals distinct three-stage crack evolution characteristics with temperature-dependent density following an exponential model. High-temperature exposure significantly reduces dynamic strength ratio (60% at 800 °C) and diminishes strain-rate sensitivity, with dynamic increase factor decreasing from 1.0 to 2.2 (25 °C) to 1.0–1.3 (800 °C). Critically, the coupling methodology captures fundamental energy redistribution mechanisms: thermal crack networks alter elastic energy proportion from 75% to 35% while increasing fracture energy from 5% to 30%. Numerical predictions demonstrate excellent experimental agreement (±8% peak stress–strain errors), validating the PFC-FDEM coupling accuracy. This integrated framework provides essential computational tools for predicting complex thermal–mechanical rock behavior in underground engineering applications.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"35 9","pages":"Pages 1555-1589"},"PeriodicalIF":13.7,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145420432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}