Editorial: Sustainability and Environmental Considerations in Mining: From Deep-Sea to Solid Earth

Zhuangcai Tian^1*Shengjie Rui²Jinran Wu³Ning Fan⁴Lei Guo⁵

• ¹China University of Mining and Technology, Xuzhou, China
• ²Norges Geotekniske Institutt, Oslo, Norway
• ³The University of Queensland, Brisbane, Australia
• ⁴Wenzhou University, Wenzhou, China
• ⁵Shandong University, Jinan, China

Mineral resources serve as a fundamental component of industrial production and exert a significant influence on global economic development, strategic security, and international trade patterns (Ma et al., 2023;Tian et al., 2024). The global distribution of major mineral resources is markedly uneven. As terrestrial metal resources become increasingly depleted, attention has shifted toward marine sources. Marine mineral resources encompass a variety of minerals found in coastal and deep-sea environments (Fan et al., 2022). Based on their formation processes, these resources are categorised into three main types: sand minerals, seabed authigenic minerals, and seabed consolidated rock minerals, which include oil and gas, polymetallic nodules, and gas hydrates, among others.The deep sea, which covers over 60% of the Earth's surface, remains largely unexplored and is characterised by a diverse array of geological features shaped by distinct sedimentary processes (Tian et al., 2019;2022). Deep-sea sediment transport, defined as the movement of sediment particles across the ocean floor, is influenced by multiple factors, including bottom currents, turbidity currents, and biological activity (Fan et al., 2023;2025). The emergence of deep-sea mining has added complexity to sediment transport dynamics, involving the extraction of valuable minerals such as polymetallic nodules, seafloor massive sulfides, and crusts from the ocean floor. The potential environmental consequences of deep-sea mining are a growing concern, as these activities can cause sediment resuspension, disrupt benthic habitats, and release toxic elements into the marine environment (Li et al., 2023). Therefore, the investigation of deep-sea sediment transport and the environmental implications of mining activities represents a multidisciplinary field that integrates geology, oceanography, and related disciplines.The increasing focus on deep-sea resource extraction raises significant concerns regarding the environmental impact of sediment disturbances resulting from mining operations (Dong et al., 2025). These activities have the potential to disrupt the fragile equilibrium of deep-sea ecosystems, alter sediment transport dynamics, and cause irreversible damage to marine environments. Consequently, the objective of this research topic is to establish a comprehensive framework for the sustainable management of deep-sea sediment transport and mining activities. This framework seeks to minimise environmental impacts while facilitating the responsible extraction of deep-sea resources. This special issue brings together a diverse collection of studies that address sustainability and environmental considerations in mining from multiple perspectives. The contributions span advanced computational methods, innovative geological modelling techniques, experimental investigations of rock behaviour under extreme conditions, and novel geophysical detection approaches. Collectively, these papers demonstrate how interdisciplinary research-from machine learning to material science and seismic imaging-can provide new insights and tools for managing the environmental challenges of both deep-sea and solid Earth mining activities.Lee et al. proposed a machine learning framework for classifying seabed sediments using both multibeam and sampling data. Five machine learning models-Random Forest, Support Vector Machine, Deep Neural Network, Extreme Gradient Boosting, and Light Gradient Boosting Machine-were trained to predict sediment compositions (gravel, sand, clay, and silt). Validation against field data from the East Sea of South Korea demonstrated significant improvements in prediction accuracy, particularly with the Extreme Gradient Boosting model. Overall, comparing the study's results, we found that the prediction accuracy improved from 60.81% before using the proposed method to 72.73% after using it.Gao et al. designed a novel technical workflow and a set of three-dimensional structure modelling methods for geological bodies containing complex faults. A model stitching strategy based on the ear clipping algorithm was proposed to incorporate fine fault models into the modified original model. A multi-layer triangulated irregular network-3DT model was constructed through continuous stratum modelling, fine fault modelling, overlap detection based on the two-dimensional projection topological relationship, extraction of ordered contour line segments of model boundaries, and model reconstruction based on the ear clipping. An underground modelling experiment revealed that these modelling methods and technical systems can accurately depict the geometric form around complex geological faults.Zhang et al. comprehensively characterised the temperature-dependent structural alterations and fluid transport properties by integrating experimental approaches. The results indicate that as the temperature increases, the mass loss rate and porosity of gneiss significantly increase. Seepage simulation reveals that the absolute permeability increases by approximately 135% at 800°C. Microscopic analysis reveals that the evaporation of intercrystalline bound water and differential thermal expansion of minerals are the main causes of crack propagation. This study innovatively combines X-CT scanning technology with digital core analysis to establish a three-dimensional quantitative evaluation system for gneiss fractures, offering theoretical and technical support for deep mining engineering.Huang et al. investigated wide-azimuth detection utilising a CO2-concentrated source through theoretical analysis, three-dimensional numerical simulation, and physical analysis. The studies establish that the dominant excitation direction for channel wave advanced detection using concentrated force sources is horizontal and perpendicular to the tunnel axis. Based on the Y-direction concentrated force source, a study was conducted on the characteristics of a wide-azimuth three-dimensional three-component seismic wavefield. The migration process is carried out using fault characteristic waves. Compared with the narrow-azimuth observation systems, the wide-azimuth observation systems can effectively eliminate symmetry artifacts, further verifying the effectiveness of the method.Together, these contributions highlight the interdisciplinary progress in applying machine learning, geological modelling, material characterisation, and geophysical detection toward more sustainable and environmentally conscious mining practices The contributions in this collection show how different strands of research can be brought together to address the environmental and sustainability challenges facing mining today. Approaches based on machine learning, three-dimensional geological modelling, experimental studies of rock behaviour, and advanced seismic detection each tackle specific problems, but they also point to a common direction: improving safety, reducing uncertainty, and limiting the environmental footprint of mining activities. Sustainable mining will depend not only on technical solutions but also on how these methods are integrated into practice, from operational planning to long-term environmental management. As attention shifts increasingly toward deep-sea resources and more complex solid Earth environments, there is a clear need for closer collaboration across geology, engineering, oceanography, and environmental science. By linking practical innovation with a stronger awareness of ecological risk, the field can move toward resource development that is both responsible and resilient. Tian, Z., Guo, X., Qiao, L., Jia, Y., & Yu, L. (2019). Experimental investigation of slope sediment resuspension characteristics and influencing factors beneath the internal solitary wave-breaking process. Bulletin of Engineering Geology and the Environment, 78(2), 959-967. Tian, Z., Huang, J., Xiang, J., & Zhang, S. (2024). Suspension and transportation of sediments in submarine canyon induced by internal solitary waves. Physics of Fluids, 36(2). Tian, Z., Liu, C., Jia, Y., Song, L., & Zhang, M. (2023). Submarine trenches and wave-wave interactions enhance the sediment resuspension induced by internal solitary waves. Journal of Ocean University of China, 22(4), 983-992.