Pub Date : 2026-02-01Epub Date: 2025-12-02DOI: 10.1016/j.jappgeo.2025.106052
Sijia Li , Guangzhi Zhang , Zhenfeng Liu , Zhen Yang , Yuanyuan Tan , Jinghui Cui
This study tackles the persistent challenge of predicting thin, heterogeneous reservoirs within fault-fracture-modified tight sandstone formations by proposing a multi-facies constrained geostatistical inversion method. Traditional lithofacies-constrained geostatistical inversion methods fail to resolve high heterogeneity and accurately find low Poisson impedance “sweet spots”. To overcome these limitations, we redefine fault-fracture bodies as distinct geological facies and integrate them with lithofacies constraints within a Bayesian inversion framework to facilitate the building of the variogram with the aim of realizing partition modeling. Curvature and structural entropy are preferred as the tools to characterize the fault-fracture bodies to guide spatial modeling. Application in a western China basin demonstrates superior performance over conventional methods: the characterization accuracy of lateral heterogeneity is improved while preserving preferable vertical resolution, high-quality sandstone reservoirs are precisely positioned. The remarkable consistency between the predicted results and well log data serves as a robust validation of the proposed method's reliability. The success of this study reveals the potential of this method to conduct predictions on fractured tight sandstone thin reservoirs characterized by high lateral heterogeneity in China as well as other areas with similar geological backgrounds.
{"title":"A multi-facies constrained geostatistical inversion for predicting fractured tight sandstone thin reservoirs: a case study in Western China","authors":"Sijia Li , Guangzhi Zhang , Zhenfeng Liu , Zhen Yang , Yuanyuan Tan , Jinghui Cui","doi":"10.1016/j.jappgeo.2025.106052","DOIUrl":"10.1016/j.jappgeo.2025.106052","url":null,"abstract":"<div><div>This study tackles the persistent challenge of predicting thin, heterogeneous reservoirs within fault-fracture-modified tight sandstone formations by proposing a multi-facies constrained geostatistical inversion method. Traditional lithofacies-constrained geostatistical inversion methods fail to resolve high heterogeneity and accurately find low Poisson impedance “sweet spots”. To overcome these limitations, we redefine fault-fracture bodies as distinct geological facies and integrate them with lithofacies constraints within a Bayesian inversion framework to facilitate the building of the variogram with the aim of realizing partition modeling. Curvature and structural entropy are preferred as the tools to characterize the fault-fracture bodies to guide spatial modeling. Application in a western China basin demonstrates superior performance over conventional methods: the characterization accuracy of lateral heterogeneity is improved while preserving preferable vertical resolution, high-quality sandstone reservoirs are precisely positioned. The remarkable consistency between the predicted results and well log data serves as a robust validation of the proposed method's reliability. The success of this study reveals the potential of this method to conduct predictions on fractured tight sandstone thin reservoirs characterized by high lateral heterogeneity in China as well as other areas with similar geological backgrounds.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106052"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-11-17DOI: 10.1016/j.jappgeo.2025.106033
Yuanyuan Tan , Guangzhi Zhang , Zhengqian Ma , Xingyao Yin
Natural fracture detection is a crucial task in exploratory geophysics. Nonetheless, it remains a challenging topic to predict fracture parameters with high precision from reflection seismic data due to the subtle seismic responses of fractures and the multi-parameter ill-posed inverse problem. Consequently, we propose a new method for predicting fracture parameters using the effective azimuthal Young's modulus in terms of Fourier series. Firstly, we derive an analytical expression of the effective azimuthal Young's modulus in terms of Fourier series for rocks with vertically aligned fractures, which isolates the fracture information from the rock matrix information. The second-order Fourier coefficient of the effective azimuthal Young's modulus (EFC) is proven to be a linear function of the fracture density. Additionally, numerical analysis reveals that the second-order EFC is always negative, which can be utilized to eliminate the 90-degree uncertainty in predicting fracture orientation. On this basis, we construct a method to estimate fracture orientation and density by introducing principal component analysis (PCA) and the discrete Fourier transformation (DFT). The effective azimuthal Young's modulus is inverted from the PCA processed azimuthal seismic data using Bayesian inversion theory. The effective azimuthal Young's modulus in the form of the truncated Fourier series can forecast the fracture orientation without the 90-degree uncertainty, where DFT is used to calculate EFC. Meanwhile, the fracture density can be directly anticipated using the second-order EFC. Ultimately, synthetic and field data examples proved the proposed method can effectively delineate the stratum with relatively developed fractures.
{"title":"Fracture detection using effective Azimuthal Young's modulus in terms of Fourier series","authors":"Yuanyuan Tan , Guangzhi Zhang , Zhengqian Ma , Xingyao Yin","doi":"10.1016/j.jappgeo.2025.106033","DOIUrl":"10.1016/j.jappgeo.2025.106033","url":null,"abstract":"<div><div>Natural fracture detection is a crucial task in exploratory geophysics. Nonetheless, it remains a challenging topic to predict fracture parameters with high precision from reflection seismic data due to the subtle seismic responses of fractures and the multi-parameter ill-posed inverse problem. Consequently, we propose a new method for predicting fracture parameters using the effective azimuthal Young's modulus in terms of Fourier series. Firstly, we derive an analytical expression of the effective azimuthal Young's modulus in terms of Fourier series for rocks with vertically aligned fractures, which isolates the fracture information from the rock matrix information. The second-order Fourier coefficient of the effective azimuthal Young's modulus (EFC) is proven to be a linear function of the fracture density. Additionally, numerical analysis reveals that the second-order EFC is always negative, which can be utilized to eliminate the 90-degree uncertainty in predicting fracture orientation. On this basis, we construct a method to estimate fracture orientation and density by introducing principal component analysis (PCA) and the discrete Fourier transformation (DFT). The effective azimuthal Young's modulus is inverted from the PCA processed azimuthal seismic data using Bayesian inversion theory. The effective azimuthal Young's modulus in the form of the truncated Fourier series can forecast the fracture orientation without the 90-degree uncertainty, where DFT is used to calculate EFC. Meanwhile, the fracture density can be directly anticipated using the second-order EFC. Ultimately, synthetic and field data examples proved the proposed method can effectively delineate the stratum with relatively developed fractures.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106033"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145694551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-11DOI: 10.1016/j.jappgeo.2025.106062
Tuan Nguyen-Sy , Thi Loan Bui , Bao Viet Tran
This study introduces an optimized Physics-Informed Neural Networks (PINNs) for modeling thermal diffusion and resulted thermal stress around a wellbore, with applications in CO2 injection, geothermal energy, and black oil production. A semi-surrogate PINNs approach is developed by integrating synthetic data from closed-form solutions for short-term diffusion, significantly improving model accuracy in early diffusion regimes. The methodology employs advanced training techniques with Adam and L-BFGS optimizers to balance accuracy and efficiency. The parameterized PINNs model further extends the framework to accommodate varying diffusion coefficients, time scales, and nonlinear thermal behaviors. Validation against numerical methods demonstrates superior performance, particularly in long-term diffusion scenarios. This study provides a computationally efficient framework that is readily extendable to complex multi-physics scenarios, making it valuable for real-time applications in CO2 injection, geothermal energy, and related fields.
{"title":"An optimized physics-informed neural networks for modeling thermal stress around an open wellbore","authors":"Tuan Nguyen-Sy , Thi Loan Bui , Bao Viet Tran","doi":"10.1016/j.jappgeo.2025.106062","DOIUrl":"10.1016/j.jappgeo.2025.106062","url":null,"abstract":"<div><div>This study introduces an optimized Physics-Informed Neural Networks (PINNs) for modeling thermal diffusion and resulted thermal stress around a wellbore, with applications in CO2 injection, geothermal energy, and black oil production. A semi-surrogate PINNs approach is developed by integrating synthetic data from closed-form solutions for short-term diffusion, significantly improving model accuracy in early diffusion regimes. The methodology employs advanced training techniques with Adam and L-BFGS optimizers to balance accuracy and efficiency. The parameterized PINNs model further extends the framework to accommodate varying diffusion coefficients, time scales, and nonlinear thermal behaviors. Validation against numerical methods demonstrates superior performance, particularly in long-term diffusion scenarios. This study provides a computationally efficient framework that is readily extendable to complex multi-physics scenarios, making it valuable for real-time applications in CO2 injection, geothermal energy, and related fields.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106062"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145790707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-26DOI: 10.1016/j.jappgeo.2025.106082
Xiaojun Wang , He Zhang , Xiao Feng , Qinglin Chen , Shirong Cao , Haowen Jiang , Jian liu
Understanding damage mechanisms in rocks exhibiting different rockburst tendencies is critical for monitoring rock damage at varied risk levels via acoustic emission (AE) technology. This study conducted rockburst tendency evaluation and uniaxial compression AE tests on limestone, granite, and red sandstone. Metallographic imaging and scanning electron microscopy (SEM) tests were also performed on fracture surfaces. AE responses and failure characteristics of rocks with different rockburst tendencies were analyzed. The parameter r (RA/AF) served as a rock damage index, with its Coefficient of Variation (CV) and AE b-value calculated. The results show that AE ring-down counts have a period of decline during the unstable crack propagation stage. Limestone and granite with rockburst tendencies fail under tension-shear coupling with mutual transitions between failure modes. The CV(r) shows a gradual decrease, stabilization, and significant increase. Red sandstone without rockburst tendencies mainly undergoes tensile action, and its CV(r) remains stable after decreasing. Compared with the traditional b-value, the CV(r) more effectively identifies failure progression, and its abrupt surge serves as a precursor for failure in rocks possessing rockburst tendency.
{"title":"Acoustic emission responses and failure characteristics of rocks with varying rockburst tendencies under uniaxial loading","authors":"Xiaojun Wang , He Zhang , Xiao Feng , Qinglin Chen , Shirong Cao , Haowen Jiang , Jian liu","doi":"10.1016/j.jappgeo.2025.106082","DOIUrl":"10.1016/j.jappgeo.2025.106082","url":null,"abstract":"<div><div>Understanding damage mechanisms in rocks exhibiting different rockburst tendencies is critical for monitoring rock damage at varied risk levels via acoustic emission (AE) technology. This study conducted rockburst tendency evaluation and uniaxial compression AE tests on limestone, granite, and red sandstone. Metallographic imaging and scanning electron microscopy (SEM) tests were also performed on fracture surfaces. AE responses and failure characteristics of rocks with different rockburst tendencies were analyzed. The parameter r (RA/AF) served as a rock damage index, with its Coefficient of Variation (CV) and AE b-value calculated. The results show that AE ring-down counts have a period of decline during the unstable crack propagation stage. Limestone and granite with rockburst tendencies fail under tension-shear coupling with mutual transitions between failure modes. The CV(r) shows a gradual decrease, stabilization, and significant increase. Red sandstone without rockburst tendencies mainly undergoes tensile action, and its CV(r) remains stable after decreasing. Compared with the traditional b-value, the CV(r) more effectively identifies failure progression, and its abrupt surge serves as a precursor for failure in rocks possessing rockburst tendency.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106082"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Passive seismic studies have made significant advancements in subsurface structure modeling. However, retrieving body-wave reflections remains challenging. This study aims to overcome this challenge through transient noise modeling and field-data application in the Dehdasht Area in southwestern Iran. In the synthetic modeling, noise sources were randomly distributed in both time and space to emulate the stochastic nature of passive seismic noise. Reflections were extracted using cross-correlation and cross-coherency techniques from both the synthetic model and the real Dehdasht data, and common virtual shot gathers were generated after suppressing surface waves to enhance reflection visibility. Even with a limited number of stations (13) and large inter-station spacing (2 km), The results demonstrate that passive seismic interferometry can successfully retrieve deep reflection waves (up to ∼7 s two-way travel time), largely independent of data acquisition geometry. Moreover, reflection hyperbolas in the virtual shot gathers were clearer when using the cross-coherency method compared to cross-correlation. A comparative analysis between common virtual shot gathers and corresponding active-source shots confirmed the consistency of retrieved reflections, highlighting the potential of passive seismic interferometry as a complementary tool to active source methods, particularly in areas with complex geological structures and high wave attenuation observed in active-source data and those identified in passive seismic recordings.Keywords: cross-coherency, cross-correlation, modeling, reflection, passive signals, virtual shot gather.
{"title":"Retrieving reflections using passive seismic modeling: A case study based on passive seismic operation in Dehdasht Area, SW Zagros, Iran","authors":"Fatemeh Alsadat Tayeb Hosseini , Zaher-Hossein Shomali , Javad Jamali , Mohammad Reza Hatami","doi":"10.1016/j.jappgeo.2025.106076","DOIUrl":"10.1016/j.jappgeo.2025.106076","url":null,"abstract":"<div><div>Passive seismic studies have made significant advancements in subsurface structure modeling. However, retrieving body-wave reflections remains challenging. This study aims to overcome this challenge through transient noise modeling and field-data application in the Dehdasht Area in southwestern Iran. In the synthetic modeling, noise sources were randomly distributed in both time and space to emulate the stochastic nature of passive seismic noise. Reflections were extracted using cross-correlation and cross-coherency techniques from both the synthetic model and the real Dehdasht data, and common virtual shot gathers were generated after suppressing surface waves to enhance reflection visibility. Even with a limited number of stations (13) and large inter-station spacing (2 km), The results demonstrate that passive seismic interferometry can successfully retrieve deep reflection waves (up to ∼7 s two-way travel time), largely independent of data acquisition geometry. Moreover, reflection hyperbolas in the virtual shot gathers were clearer when using the cross-coherency method compared to cross-correlation. A comparative analysis between common virtual shot gathers and corresponding active-source shots confirmed the consistency of retrieved reflections, highlighting the potential of passive seismic interferometry as a complementary tool to active source methods, particularly in areas with complex geological structures and high wave attenuation observed in active-source data and those identified in passive seismic recordings.Keywords: cross-coherency, cross-correlation, modeling, reflection, passive signals, virtual shot gather.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106076"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-11DOI: 10.1016/j.jappgeo.2025.106064
Yiliang Luo , Gulan Zhang , Shiyun Ran , Xiangwen Li , Jing Duan , Chenxi Liang , Qihong Zhong , Jiawei Zhang , Caijun Cao
The popular seismic facies-guided high-precision geological anomaly identification method (FHGI) can minimize the impacts of the complexity of seismic data, the accuracy of horizon times (or depths) of the target horizons, and the space-variant seismic wavelet, thereby resulting in high-precision geological anomaly identification results; however, it still requires the horizon time information and has limitations in computational efficiency. In this paper, to achieve high-efficiency and high-precision geological anomaly identification without the horizon time information, we propose a deep learning high-precision geological anomaly identification method (HGIM). HGIM is composed of the flowchart of HGIM, the FHGI-based high-precision geological anomaly identification label automatic generation (FLG), the deep learning high-precision geological anomaly identification network (HGIN), and the loss function of HGIM. FLG aims to use the FHGI results and data augmentation to generate sufficient training data for HGIN; HGIN takes three-dimensional (3D) seismic data as its inputs, the corresponding geological anomaly labels obtained by FLG as its labels, and uses the 3D convolution kernel for high-precision geological anomaly identification; The loss function of HGIM aims to calculate the loss function which focuses on the geological anomalies. An actual 3D seismic data example demonstrates that HGIM has great potential as a technique for high-efficiency and high-precision geological anomaly identification.
{"title":"Deep learning high-precision geological anomaly identification method and application","authors":"Yiliang Luo , Gulan Zhang , Shiyun Ran , Xiangwen Li , Jing Duan , Chenxi Liang , Qihong Zhong , Jiawei Zhang , Caijun Cao","doi":"10.1016/j.jappgeo.2025.106064","DOIUrl":"10.1016/j.jappgeo.2025.106064","url":null,"abstract":"<div><div>The popular seismic facies-guided high-precision geological anomaly identification method (FHGI) can minimize the impacts of the complexity of seismic data, the accuracy of horizon times (or depths) of the target horizons, and the space-variant seismic wavelet, thereby resulting in high-precision geological anomaly identification results; however, it still requires the horizon time information and has limitations in computational efficiency. In this paper, to achieve high-efficiency and high-precision geological anomaly identification without the horizon time information, we propose a deep learning high-precision geological anomaly identification method (HGIM). HGIM is composed of the flowchart of HGIM, the FHGI-based high-precision geological anomaly identification label automatic generation (FLG), the deep learning high-precision geological anomaly identification network (HGIN), and the loss function of HGIM. FLG aims to use the FHGI results and data augmentation to generate sufficient training data for HGIN; HGIN takes three-dimensional (3D) seismic data as its inputs, the corresponding geological anomaly labels obtained by FLG as its labels, and uses the 3D convolution kernel for high-precision geological anomaly identification; The loss function of HGIM aims to calculate the loss function which focuses on the geological anomalies. An actual 3D seismic data example demonstrates that HGIM has great potential as a technique for high-efficiency and high-precision geological anomaly identification.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106064"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145790706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-16DOI: 10.1016/j.jappgeo.2025.106059
Kuijie Cai, Xing Zhang, Yuqing Wang, Shujuan Wang
Seismic dip is a key attribute for subsurface interpretation and subsequent processing such as noise attenuation and seismic interpolation. However, existing estimation methods are often vulnerable to strong random noise and intersecting seismic events. Strong random noise can severely degrade data quality and complicate the interpretation of subsurface structures. We propose a Dip-Informed Radon Dictionary (DIRD) method that simultaneously estimates seismic dip and suppresses random noise within a unified iterative framework. The core idea is the joint estimation of dip values and the denoised seismic signals by linking them through a dip-informed Radon dictionary. Noise is attenuated via a sparse reconstruction algorithm based on the dip-informed Radon dictionary, while more accurate dip estimates are obtained during the iterative suppression process. The algorithm alternately refines the dip parameters and denoised signals via sparse optimization, which significantly improves its robustness to heavy random noise. Furthermore, the DIRD framework decomposes seismic patches into multiple dip components, providing a more accurate estimation for intersecting events within the same spatial region. Experiments on synthetic data with an input SNR of −3.99 dB show that the DIRD method achieves an output SNR of 3.27 dB, outperforming FXDECON(2.25 dB) and APF(2.50 dB). The DIRD method also demonstrates superior accuracy and robustness of dip estimation compared to nonlinear PWD, structure tensor, and Radon methods in terms of mean squared error, mean absolute error, and standard deviation.
{"title":"Simultaneously seismic dip estimation and random noise attenuation via dip-informed Radon dictionary","authors":"Kuijie Cai, Xing Zhang, Yuqing Wang, Shujuan Wang","doi":"10.1016/j.jappgeo.2025.106059","DOIUrl":"10.1016/j.jappgeo.2025.106059","url":null,"abstract":"<div><div>Seismic dip is a key attribute for subsurface interpretation and subsequent processing such as noise attenuation and seismic interpolation. However, existing estimation methods are often vulnerable to strong random noise and intersecting seismic events. Strong random noise can severely degrade data quality and complicate the interpretation of subsurface structures. We propose a Dip-Informed Radon Dictionary (DIRD) method that simultaneously estimates seismic dip and suppresses random noise within a unified iterative framework. The core idea is the joint estimation of dip values and the denoised seismic signals by linking them through a dip-informed Radon dictionary. Noise is attenuated via a sparse reconstruction algorithm based on the dip-informed Radon dictionary, while more accurate dip estimates are obtained during the iterative suppression process. The algorithm alternately refines the dip parameters and denoised signals via sparse optimization, which significantly improves its robustness to heavy random noise. Furthermore, the DIRD framework decomposes seismic patches into multiple dip components, providing a more accurate estimation for intersecting events within the same spatial region. Experiments on synthetic data with an input SNR of −3.99 dB show that the DIRD method achieves an output SNR of 3.27 dB, outperforming FXDECON(2.25 dB) and APF(2.50 dB). The DIRD method also demonstrates superior accuracy and robustness of dip estimation compared to nonlinear PWD, structure tensor, and Radon methods in terms of mean squared error, mean absolute error, and standard deviation.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106059"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145790734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2026-01-02DOI: 10.1016/j.jappgeo.2025.106090
Xinlei Cai , Qianyi Li , Xuliang Feng , Yang Zhang , Zheng Li , Tong Luo , Mingpu Fan , Guoqiang Zhang , Mengyao Li
Helium, an important strategic rare gas resource, has a wide range of industrial applications and utilization value. Weihe Basin in central China exhibits considerable potential for the development of helium resource. The origin of helium is predominantly governed by helium source rocks. However, the distribution of helium source rocks in Weihe Basin remains unclear at least. The aeromagnetic survey is an essential method to find out the distribution characteristics of helium source rock. In 2018, Shaanxi Gas Group Co., Ltd. obtained the first helium exploration right of China in the Huazhou-Huayin area of Weihe Basin. Aeromagnetic surveys at a scale of 1:50,000 were conducted in the Huazhou-Huayin area, and yielding high-quality magnetic field data. Using the outcrop of granite pluton nearly study area as a reference, the residual magnetic anomalies potentially associated with helium source rocks were extracted from the magnetic anomalies reduced to the pole. Three-dimensional magnetic susceptibility inversion was performed to delineate the spatial distribution of these source rocks, and the results indicate that Huashan pluton is the primary helium source rock in the Huazhou-Huayin area. The Dafuyu granite body, locating in the west of Huashan pluton, extends approximately 5000 m northward beneath the thick sedimentary cover. The granites encountered in the boreholes may be sporadically distributed by analyzing the magnetic susceptibility and reflection features of two seismic profiles. From the perspective of the distribution feature for the helium source rocks, the future efforts should be focused on the central part of the study area, particularly in the regions where the Dafuyu granite body extends northward into Weihe Basin.
{"title":"Spatial distribution and geological significance of helium source rocks revealed by 3D magnetic inversion in the Huazhou-Huayin area, Weihe Basin","authors":"Xinlei Cai , Qianyi Li , Xuliang Feng , Yang Zhang , Zheng Li , Tong Luo , Mingpu Fan , Guoqiang Zhang , Mengyao Li","doi":"10.1016/j.jappgeo.2025.106090","DOIUrl":"10.1016/j.jappgeo.2025.106090","url":null,"abstract":"<div><div>Helium, an important strategic rare gas resource, has a wide range of industrial applications and utilization value. Weihe Basin in central China exhibits considerable potential for the development of helium resource. The origin of helium is predominantly governed by helium source rocks. However, the distribution of helium source rocks in Weihe Basin remains unclear at least. The aeromagnetic survey is an essential method to find out the distribution characteristics of helium source rock. In 2018, Shaanxi Gas Group Co., Ltd. obtained the first helium exploration right of China in the Huazhou-Huayin area of Weihe Basin. Aeromagnetic surveys at a scale of 1:50,000 were conducted in the Huazhou-Huayin area, and yielding high-quality magnetic field data. Using the outcrop of granite pluton nearly study area as a reference, the residual magnetic anomalies potentially associated with helium source rocks were extracted from the magnetic anomalies reduced to the pole. Three-dimensional magnetic susceptibility inversion was performed to delineate the spatial distribution of these source rocks, and the results indicate that Huashan pluton is the primary helium source rock in the Huazhou-Huayin area. The Dafuyu granite body, locating in the west of Huashan pluton, extends approximately 5000 m northward beneath the thick sedimentary cover. The granites encountered in the boreholes may be sporadically distributed by analyzing the magnetic susceptibility and reflection features of two seismic profiles. From the perspective of the distribution feature for the helium source rocks, the future efforts should be focused on the central part of the study area, particularly in the regions where the Dafuyu granite body extends northward into Weihe Basin.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106090"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-05DOI: 10.1016/j.jappgeo.2025.106055
Hao Xu , Shengquan He , Feng Shen , Dazhao Song , Xueqiu He , Zhenlei Li , Majid Khan , Fanxiang Zhao
Under static-dynamic stress coupling in close-distance multi-seam mining, gob-side roadway surrounding rock and adjacent coal pillar are subjected to intense mine pressure. This study investigates coal-rock failure under coupled longitudinal-transverse wave and stress conditions. Microseismic monitoring, numerical simulations, and field measurements were conducted to show that microseismic events mainly cluster near the excavated coal seam, as well as adjacent roof and floor strata. The surrounding rock of gob-side roadway and the adjacent coal pillar (8 m wide) exhibit a higher microseismic event density compared to other areas. Under static loading, tensile failure initiates at the mid-height of the coal pillar. The roadway exhibits pronounced asymmetric deformation, with lateral displacement reaching 42 mm on the gob side and 10 mm on the coal side. Severe fragmentation occurs on the coal pillar side contributes to this asymmetric deformation. Under dynamic loading of longitudinal-transverse waves, the gob and fracture zones exhibit significantly higher attenuation than other strata. Meanwhile, surrounding rock masses and coal pillar structures show elevated dynamic responses compared to adjacent areas. The kinetic energy reaches its maximum during the longitudinal-transverse wave coupling stage, with the horizontal component exceeding the vertical component. Wave coupling intensifies asymmetric damage, leading to over 70 % of failure volume in the coal pillar. The pillar stress state transitions from compressive to tensile, with 95.8 % of the stored elastic energy released. Borehole imaging shows 7.79 m fracture depth on the pillar side and minimal damage on the coal side. The field observations confirm the reliability of numerical simulations. The analysis indicates that a remaining coal pillar above the studied coal seam causes stress concentration at the working face, with peak stress reaching 50 MPa. The combination effect of high static stress and dynamic disturbances generated by key stratum rupture serves as the main mechanism contributing to strong mine pressure behavior. This mechanism results in asymmetric roadway deformation and coal pillar instability. The findings provide a theoretical basis for optimizing support design and mitigating dynamic hazards in gob-side roadways under similar geological conditions.
{"title":"Instability and failure characteristics of surrounding rock and coal pillar of gob-side roadways under coupled longitudinal-transverse wave and stress fields during close-distance multi-seam mining","authors":"Hao Xu , Shengquan He , Feng Shen , Dazhao Song , Xueqiu He , Zhenlei Li , Majid Khan , Fanxiang Zhao","doi":"10.1016/j.jappgeo.2025.106055","DOIUrl":"10.1016/j.jappgeo.2025.106055","url":null,"abstract":"<div><div>Under static-dynamic stress coupling in close-distance multi-seam mining, gob-side roadway surrounding rock and adjacent coal pillar are subjected to intense mine pressure. This study investigates coal-rock failure under coupled longitudinal-transverse wave and stress conditions. Microseismic monitoring, numerical simulations, and field measurements were conducted to show that microseismic events mainly cluster near the excavated coal seam, as well as adjacent roof and floor strata. The surrounding rock of gob-side roadway and the adjacent coal pillar (8 m wide) exhibit a higher microseismic event density compared to other areas. Under static loading, tensile failure initiates at the mid-height of the coal pillar. The roadway exhibits pronounced asymmetric deformation, with lateral displacement reaching 42 mm on the gob side and 10 mm on the coal side. Severe fragmentation occurs on the coal pillar side contributes to this asymmetric deformation. Under dynamic loading of longitudinal-transverse waves, the gob and fracture zones exhibit significantly higher attenuation than other strata. Meanwhile, surrounding rock masses and coal pillar structures show elevated dynamic responses compared to adjacent areas. The kinetic energy reaches its maximum during the longitudinal-transverse wave coupling stage, with the horizontal component exceeding the vertical component. Wave coupling intensifies asymmetric damage, leading to over 70 % of failure volume in the coal pillar. The pillar stress state transitions from compressive to tensile, with 95.8 % of the stored elastic energy released. Borehole imaging shows 7.79 m fracture depth on the pillar side and minimal damage on the coal side. The field observations confirm the reliability of numerical simulations. The analysis indicates that a remaining coal pillar above the studied coal seam causes stress concentration at the working face, with peak stress reaching 50 MPa. The combination effect of high static stress and dynamic disturbances generated by key stratum rupture serves as the main mechanism contributing to strong mine pressure behavior. This mechanism results in asymmetric roadway deformation and coal pillar instability. The findings provide a theoretical basis for optimizing support design and mitigating dynamic hazards in gob-side roadways under similar geological conditions.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106055"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-01Epub Date: 2025-12-15DOI: 10.1016/j.jappgeo.2025.106068
Yizhou Lu , Bin Ma , Qingyun Wang , Jianxing Zhang , Lei Ai , Weifan Mao , Zhao Li , Zhuting Yu , Yinglin Guo
In recent years, persistent armed conflicts have posed a threat to the safety of people’s lives and property due to the presence of unexploded ordnance (UXO). The detection of UXO is an urgent yet challenging issue. When employing electromagnetic methods for subsurface UXO detection, it is difficult to distinguish between signals emitted by UXO and those from harmless clutter, leading to a high false alarm rate in UXO detection, which wastes manpower and financial resources. In this paper, we have implemented a UXO detection model based on Long Short-Term Memory (LSTM) networks, which learns pattern information from frequency-domain electromagnetic signals to differentiate between UXO, clutter, and background noise. Furthermore, we conducted orthogonal experiments across multiple levels for three critical factors – burial depth, sensor height, and UXO dip angle – to collect frequency-domain electromagnetic data using a customized ordnance model. The detection model excels on the dataset, achieving high accuracy and recall, which suggests that it can identify approximately all of UXOs while maintaining minimal false alarm rates. We conducted a multi-factor analysis of variance to systematically evaluate the impact of the key factors on detection performance. Our findings indicate that sensor height significantly influences the detection model’s performance, offering valuable insights and guidance for real-world UXO detection operations.
{"title":"Unexploded ordnance detection with deep learning: A LSTM-based approach with multi-factor analysis","authors":"Yizhou Lu , Bin Ma , Qingyun Wang , Jianxing Zhang , Lei Ai , Weifan Mao , Zhao Li , Zhuting Yu , Yinglin Guo","doi":"10.1016/j.jappgeo.2025.106068","DOIUrl":"10.1016/j.jappgeo.2025.106068","url":null,"abstract":"<div><div>In recent years, persistent armed conflicts have posed a threat to the safety of people’s lives and property due to the presence of unexploded ordnance (UXO). The detection of UXO is an urgent yet challenging issue. When employing electromagnetic methods for subsurface UXO detection, it is difficult to distinguish between signals emitted by UXO and those from harmless clutter, leading to a high false alarm rate in UXO detection, which wastes manpower and financial resources. In this paper, we have implemented a UXO detection model based on Long Short-Term Memory (LSTM) networks, which learns pattern information from frequency-domain electromagnetic signals to differentiate between UXO, clutter, and background noise. Furthermore, we conducted orthogonal experiments across multiple levels for three critical factors – burial depth, sensor height, and UXO dip angle – to collect frequency-domain electromagnetic data using a customized ordnance model. The detection model excels on the dataset, achieving high accuracy and recall, which suggests that it can identify approximately all of UXOs while maintaining minimal false alarm rates. We conducted a multi-factor analysis of variance to systematically evaluate the impact of the key factors on detection performance. Our findings indicate that sensor height significantly influences the detection model’s performance, offering valuable insights and guidance for real-world UXO detection operations.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"245 ","pages":"Article 106068"},"PeriodicalIF":2.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}