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Jincheng City’s mining areas have long been plagued by surface subsidence, posing significant threats to local residents’ safety and impacting the region’s economic and social stability. Understanding and effectively monitoring the driving factors and mechanisms of surface subsidence are crucial for devising scientific prevention measures and promoting the sustainable development of mining areas. This article aims to comprehensively reveal the large-scale surface subsidence phenomenon in Jincheng City’s mining clusters by utilizing advanced remote sensing technology and machine learning models, identifying its main driving forces, and predicting future subsidence trends to provide scientific evidence for geological disaster prevention in mining areas. The study employs Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) technology, using both Permanent Scatterer Interferometric SAR (PS-InSAR) and Small Baseline Subset Interferometric SAR (SBAS-InSAR) techniques for cross-validation, to confirm the existence of surface subsidence. Further, by integrating Variational Mode Decomposition (VMD), Singular Spectrum Analysis (SSA), and Long Short-Term Memory (LSTM) networks, a high-precision time series prediction model (VMD-SSA-LSTM) was developed. The results indicate that from 2018 to 2021, the surface subsidence rates in Jincheng City ranged from − 34 to 34 mm per year, with significant variations in subsidence levels across different areas. Gaoping City exhibited the highest subsidence, with rates ranging from − 34 to 5 mm per year, while Yangcheng County showed the most pronounced subsidence changes. These variations are primarily attributed to mining activities, land use changes, and adverse geological conditions in Jincheng City. This study revealed the large-scale surface subsidence phenomenon in the mining agglomeration area of Jincheng City, and for the first time, a comprehensive ground deformation monitoring and analysis was carried out in the small-scale mining agglomeration area of Jincheng City. The development of a high-precision surface subsidence prediction model provides new insights for scientifically understanding geological disasters in mining areas. These findings are significant for formulating effective geological disaster prevention measures and land management policies. [ABSTRACT FROM AUTHOR]

Multiple active mining faces and extensive excavations under thick-hard strata in deep coal mines result in frequent strong mine earthquakes, often accompanied by significant surface subsidence deformation. Understanding the specific law of surface movement and the spatiotemporal distribution response to intense mine earthquakes is crucial for effectively preventing and mitigating dynamic disasters in deep mines. Utilizing the key layer theory, the intricate strata of the Yingpanhao Coal Mine are systematically delineated, drawing upon the engineering context of working faces 2201 and 2202 within the Ordos Chemical Co., Ltd., a subsidiary of the Shandong Energy Group. Field investigations are conducted to analyze the law of surface subsidence associated with multi-working face extraction within deep thick-hard strata, as well as to elucidate the spatiotemporal distribution characteristics of strong mine earthquakes. Furthermore, the interplay between law of surface subsidence and the spatial distribution of strong mine earthquakes is investigated, revealing a cohesive relationship between these phenomena. The research findings of this study provide certain references for the pre-control of surface subsidence and strong mine earthquakes during multiple working face and large space mining under thick-hard strata in deep coal mine with similar engineering geological conditions. [ABSTRACT FROM AUTHOR]

For a long time, the management of surface structures such as villages and rivers affected by underground coal mining has been a popular and difficult issue in coal mining. With the further tightening of environmental protection requirements, it has become challenging for some underground coal mines that lack the conditions for filling and grouting to ensure the recovery of coal resources while controlling surface subsidence. Furthermore, many such common issues have emerged in the Yushen and Binchang mining areas of Shanxi Province, as well as in several other coalfields, severely constraining the development of coal energy and ecological environmental protection. Research on numerical simulation experiments and theoretical calculations via mechanical models suggests that the presence of multiple thick and hard key strata in the overlying rocks plays a crucial role in controlling surface displacement through the interlayer shading effect. A comparison of three mining methods, namely, fully mechanized top-coal caving with a large mining height (CMTC), longwall mining with a large mining height and full-height cutting (LMHT), and layered fully mechanized top-coal caving (LCMTC), reveals peak surface displacements of 3.818 m (CMTC), 3.649 m (LMHT), and 3.32 m (LCMTC), respectively, and peak vertical stresses of 7.3 MPa (CMTC), 5.9 MPa (LMHT), and 8.3 MPa (LCMTC), respectively. Based on these findings, an artificial buffer layer technology for controlling overlying rock displacement is proposed. This technology has a significant effect on effectively controlling surface subsidence by releasing stress in the overlying rock and provides a theoretical reference and methodological insights for mines with similar operating conditions. [ABSTRACT FROM AUTHOR]

Large deformations of strata caused by shallow tunnel excavation in urban reclamation areas pose a serious threat to geological safety. In this paper, geo-mechanical model tests and numerical simulations were conducted to investigate the large deformation characteristics based on the Haicang tunnel in Xiamen, China. First, the tunnel excavation process using the double side drift method was simulated to reveal the large deformation characteristics and influencing factors. Then, geo-mechanical model tests were conducted to further investigate the deformation characteristics, stress release patterns and pore water pressure evolution. The results show that groundwater and the thickness of the backfill soil are the primary factors affecting the deformation behavior. Meanwhile, the stress release and pore water pressure dissipation resulting from the core construction procedure are direct causes of large deformation. The research results can serve as a reference for the prevention and control of large deformation in shallow buried tunnel construction. [ABSTRACT FROM AUTHOR]

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Abstract In response to the frequent occurrence of high-energy microseismic events in coal mines in China, a back propagation neural network (BPNN) prediction model based on surface subsidence data has been proposed to provide a basis for safely and efficiently predicting coal mine disasters. Theoretical research on the relationship between surface displacement, mining disturbance, and high-energy microseismic event levels has demonstrated a significant correlation among these factors. When there is a sudden increase or decrease in surface displacement or mining disturbance, the advancing working face typically exhibits dynamic characteristics. Therefore, feature parameters relevant to predicting high-energy microseismic event levels were selected as input variables for the BPNN model. Raw data from 88 sets of microseismic events in the 301 working face of the third mining area of a certain coal mine in Inner Mongolia were extracted. First, outlier preprocessing was conducted to obtain a complete dataset, which is then divided into a training set and a testing set. The BPNN model was trained with the training set and subsequently tested to evaluate its predictive performance. Finally, by comparing several model evaluation metrics, it was found that the BPNN model outperforms other common models in predicting high-energy events. The overall prediction accuracy is 86.4%, and the root mean square error (RMSE) is 0.45, indicating that the BPNN-based prediction model for high-energy microseismic events in coal mines is feasible.

Abstract Predicting and understanding the phenomenon of surface subsidence caused by coal mining in working faces with faults are important issues for safe coal mining and efficient production. In numerical simulation experiments, it was found that the phenomenon of surface subsidence manifests when faults exist, and the degree of influence of faults with different dip angles on surface subsidence varies. This phenomenon is attributed to fault activation. According to the experimental results, the impact of faults with different dip angles on surface subsidence falls into three levels: level I for 35° faults, level II for 45° and 55° faults, and level III for 65° and 75° faults. Similarly, the relationship between the difficulty of fault activation and the dip angle of faults can be categorized as 35° faults prone to activation, 45° and 55° faults difficult to activate, and 65° and 75° faults not prone to activation. The probability integral correction model for fault mining, which integrates the surface subsidence values caused by fault-induced attenuation and the subsidence arising from separation spaces, was introduced, thereby constructing a surface subsidence prediction model. This proposed prediction model can accurately predict surface subsidence, with a root mean square error of 10.74 mm between the predicted and measured values, as validated using DInSAR results from the III 6301 working face in the Jincheng mining area.

Surface subsidence is the most direct external representation of strata movement caused by coal mining. Based on the mining background of two working faces in Hongqinghe coal mine, Dongsheng coalfield, this study deduced the breaking activity of the main key stratum (MKS) in overburden through surface subsidence measurements. It is found that the advance range of surface affected is not fixed but varies with the MKS breaking. As for surface measuring points (MPs) in the same breaking activity range of the MKS, their occurrence time of displacement is basically the same, and the change trend of displacement velocity is also consistent. When the first face is mined, the MKS only bends and sinks. As the second face is mined continuously, transverse "O-X" pattern breaking occurs in the MKS. With the extension of the fracture line and the rotation of the broken blocks, the surface movement velocity increases significantly. The dominant component of the plane displacement at the MPs in the range of the arc-shaped broken block of the MKS begins to change from strike component to dip component. In contrast, that in the range of trapezoidal block experiences a reverse transition. As mining continues, the next MKS breaking begins, causing the reverse rotation of the blocks. Correspondingly, strike displacement (SD) of the MP begins to retrace its steps. As for characteristic points in the plane movement trajectory, such as the transition of dominant component between the strike and the dip component, the reentry point of SD, and zero point, their occurrence time exhibits obvious grouping, remaining basically the same for each MP in the same group. According to this grouping rule, it is inferred that the MKS breaking is not strictly "O-X" shaped, and that the arc-shaped block and trapezoidal block are fractured into multiple parallel blocks. Highlights: Spatial movement of surface caused by underground coal mining was measured. Breaking activity of the main key stratum (MKS) was deduced through surface movement. The advance range of surface affected is not fixed but varies with the MKS breaking. MKS breaking is not strictly "O-X" shaped, but fractured into several parallel blocks along dip direction. [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings and limitations of existing prediction methods and time function models in predicting the surface subsidence induced by coal mining in deep loose and thin bedrock strata, the deformation and mechanics characteristics of mining rock are analyzed comprehensively, and a near rectangular deflection function is established based on determining the spatial position of the primary key layer. Combining with the principle of probability integral method of discontinuous random medium, a spatio-temporal predictive model(SPM) is obtained to depict the development of surface subsidence throughout coal mining process, and its reliability is verified. The results demonstrate that the model can accurately invert the whole process of surface subsidence with coal mining, providing reliable outcomes. The model considers various factors relevant to coal mining, contributing to its theoretical significance. Additionally, the utilization of visual programming operations enhances the practicality and convenience of the model in engineering applications. The results are of great significance for the prevention and control of stratal subsidence disasters resulting from mining activities. [ABSTRACT FROM AUTHOR]

In response to the frequent occurrence of high-energy microseismic events in coal mines in China, a back propagation neural network (BPNN) prediction model based on surface subsidence data has been proposed to provide a basis for safely and efficiently predicting coal mine disasters. Theoretical research on the relationship between surface displacement, mining disturbance, and high-energy microseismic event levels has demonstrated a significant correlation among these factors. When there is a sudden increase or decrease in surface displacement or mining disturbance, the advancing working face typically exhibits dynamic characteristics. Therefore, feature parameters relevant to predicting high-energy microseismic event levels were selected as input variables for the BPNN model. Raw data from 88 sets of microseismic events in the 301 working face of the third mining area of a certain coal mine in Inner Mongolia were extracted. First, outlier preprocessing was conducted to obtain a complete dataset, which is then divided into a training set and a testing set. The BPNN model was trained with the training set and subsequently tested to evaluate its predictive performance. Finally, by comparing several model evaluation metrics, it was found that the BPNN model outperforms other common models in predicting high-energy events. The overall prediction accuracy is 86.4%, and the root mean square error (RMSE) is 0.45, indicating that the BPNN-based prediction model for high-energy microseismic events in coal mines is feasible. [ABSTRACT FROM AUTHOR]

To enhance existing theoretical frameworks previously confined to predicting surface subsidence for individual salt caverns, this study introduces an advanced model based on the stochastic medium theory. This innovative approach integrates the principle of displacement superposition and formulates equations for estimating surface settlements of twin salt caverns with varied cross-sectional geometries. Comparative analysis of numerical data reveals a high congruence between surface settlements derived from our model and those predicted by numerical results for twin salt caverns. Distinct from the conventional symmetrical 'single valley' subsidence profile associated with a solitary salt cavern, this model adeptly depicts the asymmetric 'double valley' topography characterizing twin salt caverns with diverse cross-sectional shapes. The burial depth and horizontal spacing of twin caverns significantly affect both the maximum influence radius and maximum settlement value. Conversely, the vertical spacing and dimensions of the twin caverns predominantly impact the surface settlement of each individual cavern. Critically, the inter-cavern center distance emerges as a pivotal factor in transitioning the subsidence profile from a 'double valley' to a 'single valley' configuration. This study provides scientific decision-making support for the long-term safe operation of energy storage salt caverns and the conservation of land resources. [ABSTRACT FROM AUTHOR]

In recent years, land subsidence has become a crucial factor affecting urban safety and sustainable development, especially in Wan'an Town. To accurately monitor and analyze the land subsidence in Wan'an Town, this study uses the PS-InSAR technique combined with an improved DEM for detailed research on land subsidence in Wan'an Town. PS-InSAR, or Permanent Scatterer Interferometric SAR, is suitable for high-precision monitoring of surface deformation. The natural neighbor interpolation method optimizes DEM data, improving its spatial resolution and accuracy. In this study, multiple periods of SAR imagery data of Wan'an Town were collected and preprocessed through radiometric calibration, phase unwrapping, and other steps. Using the PS-InSAR technique, the phase information of permanent scatterers (PS points) on the surface was extracted to establish a deformation model and preliminarily analyze the land subsidence in Wan'an Town. Concurrently, the DEM data were optimized using the natural neighbor interpolation method to enhance its accuracy. Finally, the optimized DEM data were combined with the surface deformation information extracted through the PS-InSAR technique for a detailed analysis of the land subsidence in Wan'an Town. The research results indicate that the DEM data optimized by the natural neighbor interpolation method have higher accuracy and spatial resolution, providing a more accurate reflection of the topographical features of Wan'an Town. The research found that the optimized DEM provided a more accurate reflection of Wan'an Town's topographical features. By combining PS-InSAR data, subsidence information from 2016 to 2024 was calculated. The study area showed varying degrees of subsidence, with rates ranging from 6 mm/year to 10 mm/year. Four characteristic deformation areas were analyzed for causes and influencing factors. The findings contribute to understanding urban land subsidence, guiding urban planning, and providing data support for geological disaster warning and prevention. [ABSTRACT FROM AUTHOR]

The extraction of underground mineral deposits can cause surface subsidence, which will bring danger to surface buildings or structures. In this paper, the Panlong lead–zinc mine in Guangxi, China, was taken as an example to analyze the correlation between underground mining‐induced surface subsidence trends, and the depth of extraction. Based on the stochastic probability integral method, the surface subsidence trend at various different mining depths was analyzed. The results showed that with the increase of mining depth, the surface subsidence presents an obvious increasing trend, but the rate gradually decreases. The maximum surface subsidence is closely related to the mining depth and is less notably affected by the mining size. The maximum surface subsidence along the dip direction is basically the same as that along the strike direction for the same mining depth of the same ore body. In addition, numerical simulation by FLAC3D was conducted to analyze the evolution trend of surface subsidence at different mining depths. The subsidence cloud map demonstrated a significant expansion of the subsidence area until a depth of 680 m. With the further increase of mining depth, the subsidence area did not substantially increased, while the maximum subsidence at the center of the subsidence zone was increasing. Finally, the maximum subsidence at the center of the subsidence zone was measured by Global Positioning System (GPS) monitoring instruments. The observed data showed that subsidence trend along the direction of the mineral body was basically consistent with the theoretical and numerical simulation results above. This verifies the reliability and accuracy of the above research methods for analyzing surface settlement trend. [ABSTRACT FROM AUTHOR]

Predicting and understanding the phenomenon of surface subsidence caused by coal mining in working faces with faults are important issues for safe coal mining and efficient production. In numerical simulation experiments, it was found that the phenomenon of surface subsidence manifests when faults exist, and the degree of influence of faults with different dip angles on surface subsidence varies. This phenomenon is attributed to fault activation. According to the experimental results, the impact of faults with different dip angles on surface subsidence falls into three levels: level I for 35° faults, level II for 45° and 55° faults, and level III for 65° and 75° faults. Similarly, the relationship between the difficulty of fault activation and the dip angle of faults can be categorized as 35° faults prone to activation, 45° and 55° faults difficult to activate, and 65° and 75° faults not prone to activation. The probability integral correction model for fault mining, which integrates the surface subsidence values caused by fault-induced attenuation and the subsidence arising from separation spaces, was introduced, thereby constructing a surface subsidence prediction model. This proposed prediction model can accurately predict surface subsidence, with a root mean square error of 10.74 mm between the predicted and measured values, as validated using DInSAR results from the III 6301 working face in the Jincheng mining area. [ABSTRACT FROM AUTHOR]

Shallow coal seam mining results in the formation of various bearing structures in key strata, leading to varying degrees of surface subsidence and severe disruption to the surface ecological environment. To investigate the coupled evolution characteristics of key strata fracture-bearing structures and surface subsidence in shallow coal seam mining, with a focus on the 1–2 coal seam mining at Longhua Coal Mine in northern Shaanxi as the research background, this study employed physical similarity simulation to establish the correlation between key strata fracture-bearing structures and surface subsidence. The study also utilized theoretical calculations to develop models for the trapezoidal hinged arch structure and the coupling between key strata-bearing structures and surface subsidence. Mechanical properties of bearing structures and the coupled evolution characteristics of surface subsidence were examined, and the scientific validity of the models was verified through field monitoring. The research reveals that the inclined section of the working face in shallow coal seam mining forms a trapezoidal hinged arch structure, where stress transmission actually resembles an arch shape. Based on the fracture characteristics of rock strata, this structure can be categorized into three types: a full-trapezoidal hinged arch structure, a semi-trapezoidal hinged arch structure, and a trapezoidal-like hinged arch structure. A mechanical calculation model for the trapezoidal hinged arch structure was constructed, and the mechanical calculation formula for this structure was derived based on mechanical equilibrium conditions. Using a masonry beam mechanical model, the formula for calculating the subsidence of key blocks in the key strata fracture was obtained. Based on the "masonry beam" mechanical model, a formula was derived to calculate the subsidence of key blocks in fractured key strata. The relationship between key strata-bearing structures and surface subsidence curves was analyzed, leading to the development of a calculation model for both. This model reveals the coupled evolution between rock movement and surface subsidence. Field measurements indicate a maximum surface subsidence of 1.93 m, with a subsidence coefficient of 0.65, showing that the surface helps suppress and reduce the overall subsidence. [ABSTRACT FROM AUTHOR]

The fluid–solid coupling effect is an important factor which cannot be ignored to study the surface subsidence of deep coal seam mining in the area with abundant underground water. To study the influence of boundary permeability characteristics on surface subsidence in deep near‐horizontal coal seam mining under the effect of fluid–solid coupling, the pore water pressure field, vertical stress field, surface subsidence, and vertical displacement of a rock seam during deep mining under different permeability boundary conditions were analyzed based on fluid–solid coupling theory, taking the 3−1501 working face of Erdos Hongqinghe coal mine as an example. The results revealed that the permeability characteristics of different hydraulic boundaries affected the pore water pressure, vertical stress in the rock layer, and surface subsidence during deep mining. Moreover, the trends of pore water pressure, vertical stress, and surface subsidence of a fixed‐head permeability boundary were largely the same as those under impermeable boundary conditions, but the calculated results of the fixed‐head permeability boundary were lower than those for the impermeable boundary at the same depth. The maximum surface subsidence for the fixed‐head permeable boundary condition and the impermeable boundary condition was 879 and 925 mm, respectively, which were 239 and 285 mm higher than those obtained when the fluid–solid coupling effect was neglected (an increase of 37.3% and 44.5%, respectively). The field monitoring trend for the subsidence basin aligns closely with the subsidence basin trend under the influence of fluid–solid coupling. Considering the constant head permeable boundary conditions in the context of fluid–solid coupling yields accurate surface subsidence results. The results have provided a theoretical basis for the analysis and prediction of coal mining surface subsidence considering the fluid–solid coupling effect. [ABSTRACT FROM AUTHOR]

Coal occupies a dominant position in China’s energy structure. However, overburden failure is the root cause of several safety and environmental issues. With the successive proposals of green mining and the dual-carbon strategy, the green development of coal-based energy has become the priority development direction. Overburden grout injection has become the preferred choice in the green mining technology system. The potential ecological health risk of heavy metal contamination in fly ash matrix soil was analyzed and evaluated in Xinyi coalmine. It is pointed out that only using fly ash as grouting material may cause irreversible harm to groundwater system. Based on the solid waste utilization and sustainable development, the close packing theory was adopted to determine that poorly graded gangue can be used as filling aggregate. Meanwhile, the passivation characteristics of loess to reduce the heavy metal in fly ash by increasing the water-stable aggregate content were elucidated. The properties and parameters of grouting materials composed of gangue, loess, and fly ash were analyzed, and a reasonable upper limit of slurry concentration was determined to be 72%. The field application indicates that the maximum surface subsidence is 473 mm, and the damage degree of buildings is within grade I, liberating 163 Mt of coal resources under the buildings. The harmless treatment of solid waste has been achieved, effectively reducing the negative external impact of coal mining. It is equivalent to saving 95.95 million yuan while promoting the green, safe, and sustainable development of coal enterprises. [ABSTRACT FROM AUTHOR]

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With economic development and coal resource exploitation, the area of mined-out zones is expanding continuously. The traditional waste disposal methods no longer meet the current demands, making it urgent to evaluate and reuse the surface stability of these mined-out zones. Surface residual deformation is a process where voids and fissures within the mined-out zones are gradually filled and compacted, affecting the overlying rock structure. Additionally, groundwater significantly impacts the strength of the overlying rock, leading to increased subsidence. Therefore, predicting surface residual deformation while considering the effects of groundwater is crucial for forecasting surface deformation and assessing stability in mined-out zones. This study, taking into account the characteristics of subsidence zones and the impact of groundwater on the compaction of fractured rock masses, uses equivalent mining height and probability integral methods to develop a predictive model for surface residual deformation incorporating groundwater effects. Predictions for the study area show that groundwater exacerbates surface residual deformation, with various deformation values ranging from 33.8% to 51.9%. The surface stability categories are divided into stable and essentially stable regions based on the residual deformation's impact on the working face. This model fully considers the influence of groundwater on residual deformation in mined-out zones, refining existing mining subsidence theories, addressing deformation issues caused by adverse groundwater factors, and providing a theoretical basis for predicting residual deformation and evaluating stability in mined-out zones, promoting the sustainable development of land and environmental resources in mining areas. [ABSTRACT FROM AUTHOR]

The multi-seam occurrence conditions in the western mining area have brought forth prominent and common issues such as "contradictions in mining face layout, variable overburden structure, and superimposed surface migration". Exploring the coordinated green mining technology suitable for high-intensity mining of multiple coal seams is the key to the safe and efficient mining of multiple coal seams in the western mining area. In response to the main technical challenges faced in the high-intensity mining of shallow-buried thick coal seam groups, several key technologies for the coordinated green mining of shallow-buried multi-seam groups have been systematically expounded from aspects such as the spatio-temporal layout of multi-seam mining, the stability control of the rock strata in the working face, and the surface subsidence under repeated disturbances. The following research results have been obtained: ① The interlayer interaction mechanism of high-intensity mining of multiple coal seams in the western region has been revealed. A quantitative criterion and evaluation method for repeated mining disturbances of multiple coal seams have been constructed. An innovative coordinated mining technology with the staggered distribution of “thin, medium, and thick” coal seams aiming at minimizing inter layer disturbances has been proposed. ② The stability control technology of the rock strata in the multi-seam working face has been put forward. The full overburden structure failure model has been established, and the interaction law between the support and the surrounding rock under the condition of full overburden structure failure has been revealed. On this basis, in response to the demand of using different support strategies at different positions of the multi-seam mining working face, an anti-impact double telescopic column for the working face support and a monitoring system for the support state of the advanced roadway have been developed to achieve safe, efficient and stable support in multiple areas of the working face. ③ By revealing the dynamic movement characteristics of the surface and the development law of surface fractures under the oblique superimposed mining of shallow-buried multi-seam coal seams, the determination method of the surface subsidence coefficient has been given. The key treatment technology combining "soil reconstruction – in-situ filling – micro-topography modification" for fractures in the subsidence area has been developed, effectively preventing the surface subsidence of coal mining in the loess gully area. The above core technologies have been successfully applied in more than 20 large-scale coal mines such as Zhangjiamao, Ningtiaota, and Hongliulin, providing technical support for the high-quality and sustainable development of the western mining area in China.

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Guangdong Province, home to 21 cities and a permanent population of 127.06 million people, boasts the largest provincial economy in China, contributing 11.76% to the national GDP in 2023. However, it is prone to geological hazards due to its geological conditions, extreme weather, and extensive human activities. Geohazards not only endanger lives but also hinder regional economic development. Monitoring surface deformation regularly can promptly detect geological hazards and allow for effective mitigation strategies. Traditional ground subsidence monitoring methods are insufficient for comprehensive surveys and rapid monitoring of geological hazards in the whole province. Interferometric Synthetic Aperture Radar (InSAR) technology using satellite images can achieve wide-area geohazard monitoring. However, current geological hazard monitoring in Guangdong Province based on InSAR technology lacks regional analysis and statistics of surface deformation across the entire province. Furthermore, such monitoring fails to analyze the spatial–temporal characteristics of surface deformation and disaster evolution mechanisms by considering the local geological features. To address these issues, current work utilizes Sentinel-1A/B satellite data covering Guangdong Province from 2015 to 2022 to obtain the wide-area surface deformation in the whole province using the multi-temporal (MT) InSAR technology. Based on the deformation results, a wide-area deformation region automatic identification method is used to identify the surface deformation regions and count the deformation area in each city of Guangdong Province. By analyzing the results, we obtained the following findings: (1) Using the automatic identification algorithm we identified 2394 deformation regions. (2) Surface subsidence is concentrated in the delta regions and reclamation areas; over a 4 cm/year subsidence rate is observed in the hilly regions of northern Guangdong, particularly in mining areas. (3) Surface deformation is closely related to geological structures and human activities. (4) Sentinel-1 satellite C-band imagery is highly effective for wide-area geological hazard monitoring, but has limitations in monitoring small-area geological hazards. In the future, combining the high-spatial–temporal-resolution L-band imagery from the NISAR satellite with Sentinel-1 imagery will allow for comprehensive monitoring and early warning of geological hazards, achieving multiple geometric and platform perspectives for geological hazard monitoring and management in Guangdong Province. The findings of this study have significant reference value for the monitoring and management of geological disasters in Guangdong Province. [ABSTRACT FROM AUTHOR]

The measured data of internal movement and deformation of the overburden are insufficient, the prediction is difficult and the reliability is low. A method was constructed based on geometric similarity characteristics to predict the internal movement and deformation of the overlying rock using measured surface subsidence data. This method considered the expansion and compression resulting from the movement and deformation of the overlying rock after coal mining. The research shows that when predicting the internal movement and deformation of the overlying rock near the surface. the expansion and compression of the rock can be disregarded. However, when predicting the internal movement and deformation near the mining coal seam, the expansion and compression need to be considered. Near the mining boundary, the expansion and compression can be disregarded, but in the center of the mining area, they need to be considered. The research results contribute to the green and safe mining of coal. [ABSTRACT FROM AUTHOR]

Objectives: The continuous exploitation of the Liaohe Delta oilfield has resulted in severe surface subsidence, impacting oil recovery rates, production operations, and posing threats to surface infrastructure and ecological environments. To ensure the safe exploitation of underground fluid resources and protect the regional environment, monitoring implementation is needed for this region. Methods: The method of small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technology with coherence information as weights was used to analyze the surface deformation. Using the fusion decomposition of synthetic aperture radar descending and ascending orbit results to extract both vertical and horizontal east-west deformation within the Shuguang oilfield area. Subsequently, a reservoir compaction-induced subsidence inversion model is applied to the Shuguang oilfield to simulate and interpret the observed subsidence phenomena, linking them to the underground fluid resource exploitation activities.Results: The results reveal significant ground subsidence throughout the Liaohe Delta region, particularly in the Shuguang oilfield and Huanxiling oilfield. The average line of sight subsidence rates reaching 158 mm/a and 73 mm/a, respectively. In the Shuguang oilfield, there is horizontal movement towards the subsidence center, with approximately equal magnitudes of movement on the east and west sides. The maximum horizontal movement rate is observed to be − 62 mm/a (westward motion). Furthermore, the reservoir compaction and subsidence model based on Shuguang oilfield reservoir parameters effectively invert the maximum subsidence position at the center of the oilfield, with subsidence range and magnitude consistent with the InSAR observation results. Conclusions: The study concludes that continuous exploitation of oil has led to significant ground subsidence in the Liaohe Delta region, especially in Shuguang oilfield and Huanxiling oilfield, with clear patterns of subsidence and horizontal movement detected using SBASInSAR technology. The developed reservoir compaction-induced subsidence inversion model proves effective in simulating subsidence phenomena associated with oilfield operations. These findings underscore the importance of monitoring and managing subsidence risks to ensure the safe exploitation of underground resources and to protect regional ecological environments in the Liaohe Delta region. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The caving mining method is widely used in underground iron ore mining, but the resulting surface subsidence damages vegetation, leading to significant carbon sink losses. Safely controlling the extent of surface subsidence and implementing dynamic greening are common challenges that need to be addressed for low-carbon mining. To tackle this issue, the exposure patterns of surface subsidence pits are statistically analyzed. Using the calculation formula for the distance between subsidence pits, the exposure locations of the pits along the advancing direction of the mining working face are predicted, identifying dangerous areas to avoid during truck backfill of waste rock. Two perpendicular directions around the subsidence pits are selected, where the lower edges are well-covered by loose materials, as back- fill sites for waste rock. Trucks transport waste rock from the open-pit stripping operation and safely backfill the subsidence pits in these two perpendicular directions. After the subsidence pits are backfilled to the predetermined height, dynamic greening with soil covering is performed in non-active mining areas, while surface cracks are filled with gravel and clay. After implementing these measures, the greening area of the subsidence zone in Xiaowanggou Iron Mine reached 87%, effectively maintaining the ecological environment of the mining area and significantly reducing carbon sink losses. [ABSTRACT FROM AUTHOR]

In order to study the influence of multiple karst cave factors on surface settlement during tunnel boring machine (referred to TBM hereinafter) tunnelling, a three-dimensional numerical model is built by taking a subway project as an example and combining it with MIDAS GTS NX finite element software. Secondly, the influence of the radius, height, angle, vertical net distance and horizontal distance of the karst cave on maximum surface settlement is studied and sorted under the two working conditions of treatment and lack of treatment using the gray correlation analysis method. Additionally, a multi-factor numerical model of the untreated karst cave is established. Finally, based on the preceding research, a multi-factor prediction model for maximum surface settlement is proposed and tested. The results reveal that when the karst cave is not treated, the radius and height of the karst cave have a significant effect on maximum surface settlement. Following cave treatment however, the influence of the cave parameters on maximum settlement of the surface is greatly reduced. The calculating model created in this study offers excellent prediction accuracy and good adaptability [ABSTRACT FROM AUTHOR]

In shallow buried closely spaced multi-seam mining in Jurassic Coalfield in western China, due to specific reasons, it is inevitable that the lower and upper coal seam working faces and coal pillars are overlapped, resulting in stress concentration, uneven subsidence of the ground surface, the deformation and damage of the roadway intensified. In order to decrease surface damage and stress concentration, combined with physical simulation, engineering practices and theoretical analyses, reasonable coal pillar staggered distance in shallow multi-seam mining is investigated. The evolution properties of three-field (stress field, displacement field and fracture field) based on coal pillar staggered distance (CPSD) were analyzed, the determination method of rational CPSD was put up. Research findings reveal that concentrated stress results from upper and lower pillar stress superposition, and the lower pillar should be arranged in the low-stress zone. Through rational pillar arrangement, the uneven subsidence of surface is reduced, and the concentrated fractures of overlying strata and surface are decreased. For No. 1–2 and No. 2–2 coal seam mining, as CPSD is increased, subsidence above the upper coal pillar increases and the uneven subsidence of surface decreases, the concentrated stress reduced by 25%, the width of surface fractures reduced 81.1%. Consequently, rational CPSD on the basis of coupling control of three-field can be determined, the reasonable CPSD is 40–55 m. It can provide a method to realize underground safe mining and ground surface green mining in shallow multi-seam mining.Article Highlights: Refined physical similarity model is adopted, combined with an ultra-thin stress sensors and fracture width gauge. Evolution laws of stress field, displacement field and fracture field of overlying strata are systematically analyzed. Study the characteristics of three field evolution under different CPSD of lower coal seam working face. [ABSTRACT FROM AUTHOR]

Underground coal gasification (UCG) is an efficient method for the conversion of deep coal resources into energy. The scope of this work is to model the subsidence of four gasification cavities with a size of 30 m × 30 m × 15 m, separated by 15 m wide pillars. Two scenarios of gasification sequence are modelled, one with the gasification of cavities 1 and 2 followed by 3 and 4, and the other one with the sequence of cavities 1 and 3, followed by 2 and 4. The results show that the final surface subsidence after gasification of four cavities is 9.8 mm and the gasification sequence has an impact only on the subsidence at the intermediate stage but has no impact on the final subsidence after all four cavities are formed, when only the elasticity regime is considered. Additionally, the maximum surface subsidence for the studied cavities of different sizes ranges from 0.016 mm to 7.14 mm, and the relationship between the subsidence and the cavity volume is approximately linear. Finally, a prediction model of surface subsidence deformation is built up using the elastic plate theory, and the formula of surface deformation at a random point is given. The maximum difference between measured and calculated deformation is 4.6%, demonstrating that the proposed method can be used to predict the ground subsidence induced by UCG. [ABSTRACT FROM AUTHOR]

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Surface subsidence is common geologic hazard in coal mines when longwall mining method is applied. In this research, a Bonded Block Model (BBM) is selected to numerically simulate and analyze the surface subsidence of coal mines. Parametric study is conducted and key factors controlling the subsidence are characterized. BBM models with no bedding planes realistically simulate the maximum subsidence, but overestimate the subsidence levels above the panel edges. The bedding planes introduced in the BBM models potentially provide more realistic subsidence profile. The separation of the planes and downward bending of the layered strata, as commonly observed in coal mines, are simulated and captured. In addition, high horizontal stress plays a key role in simulating more realistic subsidence profiles. The methodologies and conclusions of this research are expected to improve our understandings of the surface subsidence of coal mines and provide reliable tools to analyze and characterize this challenging issue.

Abstract To understand the mechanical response pattern of the existing structure and ground due to the construction of metro tunnels underneath, the finite difference method is adopted to study the torsional deformation and stress variation of the existing structure and the effect of underground carriageway structures on the surface subsidence. The curves of the maximum differential subsidence, torsion angle, and distortion of the cross‐section of the existing structure show two peaks in succession during traversing of two metro tunnels beneath it. The torsion angle of the existing structure changes when the two tunnels traverse beneath it in opposite directions. The first traversing of the shield tunnel mainly induces the magnitude variation in torsional deformation of the existing structure, but the second traversing of the subsurface tunnel may cause a dynamic change in the magnitude and form of torsional deformation in the existing structure. The shielding effect can reduce the surface subsidence caused by metro tunnel excavation to a certain extent, and the development trend of subsidence becomes slower as the excavation continues.

In the western mining area, coal mining is characterized by shallow burial depth, thin bedrock, multi coal seam mining, and a fragile surface environment. To address the limitations of traditional observation methods for mining-induced subsidence, such as small coverage, high operation intensity, and low automation, unmanned aerial vehicle （UAV） photogrammetry technology has been introduced to observe and analyze the surface subsidence patterns of a coal mine working face. The results show that: the UAV photogrammetry method achieves a centimeter-level observation accuracy, with a median error of 4.4 cm, which meets the overall observation requirements for surface subsidence. A surface subsidence model of the entire mining area within a 2.53 km² survey area was obtained using the UAV photogrammetry method. This model accurately reflects the subsidence area and amplitude of the surface in the mining area. Due to the influence of multiple coal seams mining, the surface subsidence model exhibits an uneven basin shape. The subsidence curves along the strike and dip of the working face show asymmetry, with a maximum subsidence value of 3.18 m.

In order to study the control mechanism of surface subsidence by the high and huge thick conglomerate strata after working face mining, the typical working face of west 11th mining area of Gaozhuang Coal Mine is taken as the background, and the research is carried out by using the theoretical analysis, numerical simulation, and the actual measurement of surface subsidence; based on the distribution of micro-seismic events, we analyzed the characteristics of overlying strata structure in the working face of the high level huge-thick conglomerate layer, and the high level huge-thick conglomerate layer is less affected by mining, and the degree of fissure development is lower; a mechanical model of Euler-Bernoulli solid-supported cracked beam in giant conglomerate strata was established, and the deflection control equations under the influence of cracks were deduced, which elucidated the control mechanism of giant conglomerate strata on surface subsidence. Numerical simulation results show that the vertical displacement of overlying strata changes abruptly at the bottom of the giant conglomerate strata, the bottom of the giant conglomerate strata is prone to generating off-stratum space, and the off-stratum space undergoes the morphology evolution of “crescent” and “disk”, and the modeled surface subsidence under the influence of the giant conglomerate strata is significantly smaller than that of the giant conglomerate layer. The amount of modeled surface subsidence under the influence of the giant conglomerate layer is significantly smaller. The measured results of surface subsidence show that the amount of surface subsidence of the working face mining in the high level giant thick conglomerate area is obviously smaller, and the high level giant thick conglomerate has an obvious controlling effect on surface subsidence.

Based on the Zhuyuan–Bailonggang sewage interconnection pipe project in Shanghai, the ABAQUS finite element software was used in numerical simulations to study the fine control of stratum disturbances caused by pipe jacking parameter deviation in soft soil areas. Combining the simulation results with onsite measured data, the Peck formula was used to predict surface settlement. The results indicate the following: (1) The jacking speed and face pressure are negatively correlated with surface settlement. Under the maximum positive deviation and negative deviations in the jacking speed, after the tail passes through the monitoring section D0 16 ring, the maximum value of settlement at point B8 increases by 21.6% and decreases by 12.8%, respectively. Increasing the jacking speed increases the area with stress change ratio R < 0 at monitoring section D0, and the arch foot at the tail of the pipe jacking machine decreases the surface settlement. In contrast, when the face pressure deviates from its average value, the variation range is less than 1%. (2) The pipe slurry coefficient and surface subsidence are positively correlated. Under the maximum positive deviation and the maximum negative deviation, the tail passes through the monitoring section D0 16 ring, and the maximum settlement value at B8 decreases by 4.9% and increases by 16.5%, respectively. The increase in the coefficient reduces the area with R < 0 at D0 and increases the surface settlement. (3) In the order of descending strength, surface settlement is affected by the jacking speed, slurry friction coefficient, and face pressure. (4) To predict the maximum surface settlement value due to deviations in the jacking parameters, the Peck formula was modified using a correction factor α ranging from 0.6 to 3.0 and a settlement trough width correction factor β ranging from 1.6 to 4.0. The modified prediction curve is in closer agreement with the actual conditions.

Mongolia's substantial mineral resources have played a pivotal role in its economic progress, with mining activities significantly contributing to this development. However, these continuous mining operations, particularly at the Oyu Tolgoi copper and gold mine, have induced land subsidence that threatens both production activities and poses risks of geological and other natural disasters. This study employs the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to monitor and analyze time-series surface subsidence using 120 Sentinel-1A datasets from 2018 to 2022. The findings reveal that the SBAS-InSAR method successfully captures the subsidence and its spatial distribution at Oyu Tolgoi, with the maximum cumulative subsidence reaching −742.01 mm and the highest annual average subsidence rate at −158.11 mm/year. Key drivers identified for the subsidence include variations in groundwater levels, active mining operations, and changes in surface stress. This research underscores the ongoing subsidence issue at the Oyu Tolgoi mining area, providing crucial insights that could aid in enhancing mining safety and environmental conservation in the region. [ABSTRACT FROM AUTHOR]

In coastal areas, due to their special geological conditions, soft soil foundation has become a common form of foundation in engineering construction. Soft soil foundation has low bearing capacity and large settlement deformation, posing a serious threat to surrounding building facilities and human life and property. Therefore, monitoring it is crucial. However, the inherent characteristics of soft soil foundation make it difficult to monitor, and traditional monitoring methods have shortcomings such as poor timeliness, low manual efficiency, and difficulty in sharing monitoring data. Therefore, in practical engineering, a combination of manual and automated methods is often used for monitoring. With the advancement of technology and the development of new technologies such as artificial intelligence, applying intelligent systems to soft soil foundation monitoring, real-time monitoring and early warning have become a new research direction. This article took a coastal soft soil foundation project as an example to introduce the application of intelligent systems in this project. [ABSTRACT FROM AUTHOR]

Water-soluble mining was invariably associated with surface subsidence, which in some cases escalated to the movement, deformation, and even collapse of the overlying rock layers, triggering grave subsidence calamities. The caprock of the salt-bearing strata in the Longgui salt rock mining area was closely adjacent to the third aquifer, which mainly consisted of fractured, porous, high-permeability materials such as mudstone conglomerates, rendering the geological conditions highly complex. Years of water-soluble mining had led to significant surface subsidence in the mining area, with a trend toward accelerated subsidence. In this study, the geological conditions of the Longgui salt rock mining area were analyzed, and through simulated experiments of pillar dissolution mining, the mechanisms of surface subsidence in the area were examined. Over time, the dissolution gradually perforated the pillars and caprock, with the pillars ceasing to support the caprock, ultimately transforming small cavities into a large single cavity. Utilizing subsidence data, this research employed numerical simulation to inverse and predict subsidence patterns from 2019 to 2025, revealing that the maximum subsidence reached 1367.6 mm in mining area I and 1879.5 mm in mining area II, with subsidence rates of 12.05 mm/y and 44.78 mm/y, respectively. Moreover, the impact of ground subsidence on the construction of adjacent subways was assessed by establishing monitoring points and evaluating subsidence along subway cross-sections and longitudinal directions. The findings provided valuable insights for guiding the prevention and control of surface subsidence calamities in the Longgui salt rock mine and similar mining areas in Guangzhou, China. [ABSTRACT FROM AUTHOR]

In order to investigate the changes in soil enzyme activity and their influencing factors in coal mining subsidence areas with high underground water levels, in this study, we collected soil samples at different depths (SL: 0–20 cm; ML: 20–40 cm; DL: 40–60 cm) in a deep coal seam subsidence area (T1), a shallow coal seam subsidence area (T2), and control non-subsidence areas (W1 and W2) in eastern China. Soil physicochemical properties and enzyme activities were determined, and the mechanism of the latter's response to coal mining subsidence was investigated based on correlation analysis, redundancy analysis, and structural equation modeling. The results show the following: (1) In the coal mining subsidence areas, the soil pH value (pH), soil available nitrogen (AN), available phosphorus (AP), available potassium (AK), and soil organic matter (SOM) contents were lower than those in the non-subsidence areas, while the soil water content (SWC) and bulk density (BD) were higher than those in the non-subsidence areas and increased with depth. (2) The activities of soil urease (URE), sucrase (SUC), alkaline phosphatase (ALP), and catalase (CAT) gradually decreased with depth and were all lower than those in the non-subsidence areas; the largest decreases with respect to the latter were 24.33%, 18.73%, 38.89%, and 5.88%, respectively. (3) The soil nutrient environment had a highly significant and direct positive effect on enzyme activity, with AN, AP, and SOM contents having the greatest impact. (4) Soil BD had a highly significant and direct negative effect and an indirect negative effect (by affecting nutrients) on enzyme activity. The results of this study on the effects of soil physicochemical properties on enzyme activity provide a basis for the ecological restoration of mines. [ABSTRACT FROM AUTHOR]

In order to explore the effect of mining sequence on surface subsidence, taking the practical production problems of a gold mine as the engineering background, different mining schemes were designed. The Flac3D software was used for numerical simulation, with surface deformation magnitude and plastic zone volume monitored as evaluation indicators to analyze the movement patterns of the surface under different mining schemes. The research results indicate that disturbances generated by simultaneous mining of two levels have a significant impact on surface movement, and the smallest surface subsidence occurs when the seventh and eighth levels are simultaneously mined. The volume of plastic zone damaged is closely related to the mining sequence, and the smaller the total volume of levels mined simultaneously, the smaller the volume of plastic zones damaged after the completion of overall mining in the mine. The research findings provide a reference basis for safe and efficient mining in the mine. [ABSTRACT FROM AUTHOR]

Underground goaf in metallurgical mining area leads to surface subsidence and has destructive effect on blast furnace. This paper studies the influence of underground goaf on blast furnace.The overlying strata and surface subsidence due to the formed gob area after the underground mining led to a different degree of destruction to blast furnace. Hence, blast furnace was modeled to theoretically analyze the additional stress applied to blast furnace body and foundation when withstanding the surface deformation. On this basis, the anti-deformation structure was designed to analyze the influences of Class I - IN surface deformation on the setting of Blast furnace body unit [ABSTRACT FROM AUTHOR]

Underground goaf in metallurgical mining area leads to surface subsidence and has destructive effect on blast furnace. This paper studies the influence of underground goaf on blast furnace.The overlying strata and surface subsidence due to the formed gob area after the underground mining led to a different degree of destruction to blast furnace. Hence, blast furnace was modeled to theoretically analyze the additional stress applied to blast furnace body and foundation when withstanding the surface deformation. On this basis, the anti-deformation structure was designed to analyze the influences of Class I - IN surface deformation on the setting of Blast furnace body unit.

Aiming at the problems of long cycle time and large workload of traditional surface movement monitoring methods, the method of acquiring ground point clouds and constructing subsidence DEM through UAV LiDAR and point cloud filtering enables surface subsidence monitoring fast and efficient. Because of the subsidence DEM models constructed by existing point cloud filtering and interpolation algorithms still cover noise, which limits the popularity of this technology in mining areas, therefore, it is significant to further study the removal method of subsidence DEM noise, compare and analyze the multiple filtering and classical filtering techniques. Experimental analysis results show that the median filter combined with Wiener filter has the best denoising effect among several denoising methods, which can keep the details of the subsidence basin and meet the basic requirements of surface deformation monitoring in mining areas.

Shallow coal seam mining results in the formation of various bearing structures in key strata, leading to varying degrees of surface subsidence and severe disruption to the surface ecological environment. To investigate the coupled evolution characteristics of key strata fracture-bearing structures and surface subsidence in shallow coal seam mining, with a focus on the 1–2 coal seam mining at Longhua Coal Mine in northern Shaanxi as the research background, this study employed physical similarity simulation to establish the correlation between key strata fracture-bearing structures and surface subsidence. The study also utilized theoretical calculations to develop models for the trapezoidal hinged arch structure and the coupling between key strata-bearing structures and surface subsidence. Mechanical properties of bearing structures and the coupled evolution characteristics of surface subsidence were examined, and the scientific validity of the models was verified through field monitoring. The research reveals that the inclined section of the working face in shallow coal seam mining forms a trapezoidal hinged arch structure, where stress transmission actually resembles an arch shape. Based on the fracture characteristics of rock strata, this structure can be categorized into three types: a full-trapezoidal hinged arch structure, a semi-trapezoidal hinged arch structure, and a trapezoidal-like hinged arch structure. A mechanical calculation model for the trapezoidal hinged arch structure was constructed, and the mechanical calculation formula for this structure was derived based on mechanical equilibrium conditions. Using a masonry beam mechanical model, the formula for calculating the subsidence of key blocks in the key strata fracture was obtained. Based on the “masonry beam” mechanical model, a formula was derived to calculate the subsidence of key blocks in fractured key strata. The relationship between key strata-bearing structures and surface subsidence curves was analyzed, leading to the development of a calculation model for both. This model reveals the coupled evolution between rock movement and surface subsidence. Field measurements indicate a maximum surface subsidence of 1.93 m, with a subsidence coefficient of 0.65, showing that the surface helps suppress and reduce the overall subsidence.

Abstract Coal mining under the geological conditions of a loose layer will lead to the intensification of surface movement and deformation, and mining under the geological conditions of a fault will lead to the living slip of a fault. Mining under both conditions will have a great impact on the safety of coal production. To reveal the evolution law of the coupling mechanism of loose layer and fault on the multi-physical fields of overburden, the numerical simulation method is used to simulate the coupling of loose layer and fault with different thicknesses, analyze the changes of vertical stress on the key strata, the changes of surface subsidence, the evolution of elastic energy on the fault zone and the changes of activated slip area of the fault zone. The simulation analysis shows that the vertical stress change trend of the key strata gradually changes from the "V" shape to the "W" shape at the beginning of mining, and the vertical stress concentration will occur at the fault. The loose layer will promote surface subsidence, and the fault will hinder the surface subsidence to a certain extent. The loose layer and the fault alternately affect the surface subsidence. The elastic energy accumulation on the key strata is mainly concentrated on both sides of the goaf. The elastic energy in the center of the goaf is dissipated. The elastic energy accumulation in the fault zone starts from the shallowly buried fault and gradually develops to the deeply buried fault. The instability of fault activation has gone through the initial stage of activation—the intensification stage of activation—the stable stage of activation. Under the working conditions of no loose layer, thin loose layer, and thick loose layer, the fault zone is the first to undergo living slip, and under the action of an extra-thick loose layer, there is a certain lag in the activation slip of the fault zone.