Journal of Applied Geophysics最新文献

{"title":"Tunnel geological forward-prospecting based on an optimized beamforming seismic method","authors":"Lei Chen ,&nbsp;Zhifei Gong ,&nbsp;Long Chen ,&nbsp;Chuanwu Wang","doi":"10.1016/j.jappgeo.2026.106135","DOIUrl":"10.1016/j.jappgeo.2026.106135","url":null,"abstract":"<div><div>Currently, more and more tunnels are being built and designed in urban and mountain areas. To ensure the safe construction of a tunnel, the seismic method is widely applied to estimate the geological conditions ahead of the tunnel face. However, due to the complex environment in the tunnel (narrow observation aperture, strong noise, etc.), it is hard to extract the effective reflected waves with poor energy for imaging geology, especially for the target far away from the tunnel face. In this paper, for the demand of geological detection in the Water Diversion Project from the Songhua River, the tunnel seismic ahead-prospecting was improved by using the adaptive beamforming approach, supporting the extraction of reflected waves with poor energy. As the core of beamforming, the delay time is an important parameter to control the reliability of stacking, especially for the various strata. The relevance analysis-based adaptive beamforming is proposed for the delay-time calculation to obtain the correlation coefficient. Among them, the reflection group composed of several reflections is used to obtain an accurate delay time first. Then, the seismic data are reconstructed and overlapped to improve the SNR based on the obtained delay time. Numerical simulation denotes that the energy of reflected waves can be enhanced significantly. Finally, the improved seismic ahead-prospecting was applied in the Water Diversion Project from the Songhua River; the method successfully predicted the fractured zones ahead of the tunnel face and guaranteed tunnel construction safety.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106135"},"PeriodicalIF":2.1,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071111","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}

{"title":"Frequency-domain fast slant stacking method based on non-uniform fast Fourier transform for dispersion imaging from dense array ambient seismic noise","authors":"Chaoqiang Xi ,&nbsp;Hao Zhang ,&nbsp;Ya Liu ,&nbsp;Ling Ning","doi":"10.1016/j.jappgeo.2026.106136","DOIUrl":"10.1016/j.jappgeo.2026.106136","url":null,"abstract":"<div><div>Ambient-noise interferometry from dense seismic arrays provides rich surface-wave information for dispersion imaging and multiscale shear-wave velocity Vs inversion, but it also produces very large virtual shot gathers that make conventional frequency-domain slant stacking computationally expensive. We present a frequency-domain fast slant-stacking method based on the non-uniform fast Fourier transform NUFFT for dispersion imaging from dense-array ambient seismic noise. Synthetic and field tests show that the NUFFT-based formulation yields same dispersion spectra and picked dispersion curves that are identical to those obtained by conventional direct summation, with an RMS misfit of 0. Benchmarks on three field datasets demonstrate substantial runtime reductions, requiring 1.44–2.23 s and 0.33–0.49 s with parallelization for NUFFT, whereas Numba, PyTorch, and NumPy implementations typically require tens to hundreds of seconds under the same settings, achieving speedups of up to about 60 times relative to the fastest conventional baseline. Comparisons with the widely used CC-FJpy package show consistent dispersion trends while requiring significantly less computation time.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106136"},"PeriodicalIF":2.1,"publicationDate":"2026-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081613","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}

{"title":"A new method for reconstructing surface wavefields via cross-correlation of ambient noise from DAS and geophone records","authors":"Wenda Sun,&nbsp;Jing Zheng,&nbsp;Suping Peng","doi":"10.1016/j.jappgeo.2026.106121","DOIUrl":"10.1016/j.jappgeo.2026.106121","url":null,"abstract":"<div><div>Distributed Acoustic Sensing (DAS) is an emerging seismic acquisition technology that offers high spatial sampling density, continuous recording capability, and flexible deployment. These characteristics make it particularly suitable for shallow subsurface exploration in urban environments. However, DAS exhibits limited sensitivity to weak seismic signals and typically captures only the axial component of ground motion. In contrast, conventional geophones offer high signal fidelity and multi-component recordings, but are limited by lower spatial resolution, greater deployment costs, and reduced adaptability in complex terrain conditions. To enhance surface wavefields reconstructed from DAS ambient noise, we propose a method that integrates the complementary strengths of DAS and conventional geophones. The method employs a linear array configuration, where the vertical component of a geophone deployed at the front of the array serves as a virtual source, and the DAS system is deployed along the subsequent positions of the array to serve as receivers. These recordings are combined to form a hybrid ambient noise dataset, which is processed in the frequency domain through normalization and cross-correlation. The acausal parts of the cross-correlation functions (CCFs) are taken as virtual shot gathers (VSGs). This method not only preserves the high spatial resolution of DAS but also incorporates the high signal fidelity of geophones, thereby significantly enhancing the surface wavefields in passive surface wave imaging. By evaluating the signal-to-noise ratio (SNR) of randomly selected traces from the CCFs obtained under various ambient noise stacking durations, the proposed method achieves average SNR improvements of 1.54 dB and 1.00 dB compared to the case where both the virtual source and receivers are derived from DAS data. Under the optimal stacking duration, the extracted dispersion energy shows clearer and more concentrated patterns, with an extended frequency range.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106121"},"PeriodicalIF":2.1,"publicationDate":"2026-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071110","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}

{"title":"Petrophysics and mass balance integration for alteration detection in orogenic gold exploration","authors":"Yasaman Nemati ,&nbsp;J. Christian Dupuis ,&nbsp;Benoit Quesnel ,&nbsp;Bernard Giroux ,&nbsp;Richard Smith ,&nbsp;Georges Beaudoin","doi":"10.1016/j.jappgeo.2026.106114","DOIUrl":"10.1016/j.jappgeo.2026.106114","url":null,"abstract":"<div><div>This study explores the integration of petrophysical and geochemical data to characterize hydrothermal alteration in mafic and ultramafic rocks, with a focus on the Augmitto-Bouzan orogenic gold deposit in the Abitibi Greenstone Belt. Employing established mass balance techniques using zirconium (Zr) as the immobile reference element, we quantified element mobility during alteration processes. Due to the absence of original komatiite protolith data, we compiled geochemical compositions from published sources across the Superior Province and applied bootstrapping to derive a representative baseline for mass balance calculations, which were then correlated with petrophysical logs from multiple boreholes to identify modification signatures. The analysis reveals robust correlations: potassium enrichment aligns with elevated gamma-ray responses, carbonate alteration is marked by increased CaO and reduced density, and magnetic susceptibility decreases correspond to Fe-Mg depletion and sulfide mineralization. These observations demonstrate systematic links between geochemical changes and petrophysical data, showing that petrophysical logs can serve as high-resolution, cost-effective proxies for alteration mapping, offering a scalable framework for exploration targeting in orogenic gold systems hosted in ultramafic rocks. The methodology bridges traditional geochemistry and in-situ measurements of physical properties, improving subsurface characterization and supporting the development of data-driven exploration tools while advancing our understanding of processes associated with gold mineralization.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"246 ","pages":"Article 106114"},"PeriodicalIF":2.1,"publicationDate":"2026-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146079089","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}

{"title":"A FFT-based calculation method for third-order gradient tensor of gravity potential from vertical gravity gradient data","authors":"Feng Qiu ,&nbsp;Zhengwang Hu ,&nbsp;Jinsong Du ,&nbsp;Songtao Hu","doi":"10.1016/j.jappgeo.2026.106125","DOIUrl":"10.1016/j.jappgeo.2026.106125","url":null,"abstract":"<div><div>With the same distribution of the observation points, the third-order gravitational gradient tensor is capable of acquiring more comprehensive information pertaining to the geophysical field and its corresponding sources, demonstrates superior sensitivity to changes in the burial depth of field sources, and features enhanced horizontal resolving power. But the current instrumental measurement technology has not yet reached the level of measuring the third-order gradient tensor of gravitational potential directly in the field. In this paper, we provide an alternative technique for calculating the complete third-order gradient tensor of gravitational potential from the pre-existing vertical gravity gradient data by using the fast Fourier transform (FFT). In order to verify the correctness of the transform calculation method, the complete third-order gradient tensor components of gravitational potential are computed from the synthetic vertical gravity gradient data by two different three-dimensional (3-D) theoretical density models. Comparing the FFT-based calculation results with theoretically forward calculated data shows that the root-mean-square (RMS) error for each component, is at most 1.5 pMKS (1 pMKS = 10⁻¹² m⁻¹·s⁻²). In addition, as a real example, based on the practically measured vertical gravity gradient data over the Vinton salt dome area, the complete third-order gradient tensor is obtained by using the FFT-based calculation method and the results illustrate a better resolution and a richer information for understanding the underground density structures. Then, the determined tensor data is quantitatively interpreted by using the DEXP (i.e., Depth from EXtreme Point) imaging technique. The imaging results show that, the depth and boundaries of anomalous density sources by the DEXP imaging method are consistent with the previous research results, and the third-order gradient tensor-based imaging has a weaker influence of trend component than the traditional gravity and second-order gravity gradient tensor. Both synthetic examples and practical application suggest that our proposed method is not only valid and reliable but also has a high computational efficiency due to the FFT algorithm, and meanwhile the calculated third-order gradient tensor also provides a novel way for exploring the geological structures, ore bodies and hydrocarbon reservoirs, etc.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106125"},"PeriodicalIF":2.1,"publicationDate":"2026-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071108","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}

{"title":"Automatic identification and location of underground defects in urban roads via ground penetrating radar and deep learning approaches","authors":"Jiwei Zhang ,&nbsp;Xiaoyi Ji ,&nbsp;Mingzhe Zhao ,&nbsp;Yaxiu Li ,&nbsp;Haifeng Wang ,&nbsp;Ming Zhong ,&nbsp;Shuai Li","doi":"10.1016/j.jappgeo.2026.106128","DOIUrl":"10.1016/j.jappgeo.2026.106128","url":null,"abstract":"<div><div>Underground defects in urban roads endanger driving safety and hinder road usability. These defects are primarily identified using technologies such as ground penetrating radar. The current intelligent algorithms used for identifying underground road defects rely heavily on large datasets of on-site road images. However, the automatic detection of defects remains challenging due to small datasets, limited image availability, and inconsistent on-field image quality. This paper proposes a novel approach to address these challenges through a model based on actual road conditions and forward simulations of road defect images. To improve the quality of both real and simulated field images, we apply a joint denoising method that combines wavelet transform, the <em>K-SVD</em> algorithm, and bilateral filtering. This denoising process enhances both real and simulated field images and expands the image dataset, transforming it into a mixed database, and strengthens the distinctive features of each defect, facilitating more accurate algorithm-based detection. In the first and second stages of the study, we conduct a comparative analysis of various deep learning-based object detection models. We then propose a deep learning model, optimized with the joint denoising model, that is best suited for practical road evaluation projects. The model was trained and validated across 100 km of high-quality field measurement data collected from various districts and counties in Beijing. Experimental results showed that the model can achieve a prediction accuracy of 82.3% for Looseness, 92.6% for Cavities, and 50.9% for Voids, with an overall Mean Average Precision of 75.3%. These results demonstrate that the method proposed in this study can enhance the detection accuracy for various subsurface defects.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106128"},"PeriodicalIF":2.1,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146071109","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}

{"title":"Target-oriented full waveform inversion based on optimal transport theory","authors":"Tianjing Shen ,&nbsp;Xiaochun Chen ,&nbsp;Kai Chen ,&nbsp;Yukai Wo ,&nbsp;Xuri Huang","doi":"10.1016/j.jappgeo.2026.106120","DOIUrl":"10.1016/j.jappgeo.2026.106120","url":null,"abstract":"<div><div>Target-oriented full waveform inversion (TOFWI) provides an efficient strategy for high-resolution imaging in local regions of interest, but its effectiveness is often limited by two main challenges: the need for redatuming of the acquisition system and the sensitivity of conventional <span><math><msub><mi>L</mi><mn>2</mn></msub></math></span>-norm-based TOFWI (<span><math><msub><mi>L</mi><mn>2</mn></msub></math></span>-TOFWI) to initial models and data quality. In this study, we propose an optimal transport (OT)-based TOFWI framework to overcome these limitations. First, we apply the Marchenko redatuming method to retrieve virtual reflection responses that isolate the target-zone wavefield. Then, we incorporate OT-based misfit functions, including graph-space OT (GSOT) and Kantorovich-relaxed OT (KROT), to enhance the convexity of the inversion landscape and improve robustness against noise and velocity-model inaccuracies. KROT introduces entropy regularization via the Sinkhorn algorithm, leading to smooth transport plans and improved numerical stability, whereas GSOT relies on a discrete assignment formulation that yields sparse transport plans and higher sensitivity to local waveform variations. Numerical experiments demonstrate that the proposed OT-TOFWI framework delivers more accurate and stable reconstructions than conventional <span><math><msub><mi>L</mi><mn>2</mn></msub></math></span>-TOFWI, particularly under conditions of significant initial-model errors and low signal-to-noise ratio. Furthermore, comparisons with global full waveform inversion highlight that OT-TOFWI achieves better resolution in deeper structures with lower computational cost. These results confirm that integrating Marchenko redatuming with OT-based misfit functions provides a promising pathway for reliable target-oriented seismic imaging in complex geological settings.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"246 ","pages":"Article 106120"},"PeriodicalIF":2.1,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146079091","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}

{"title":"Application of geophysical methods in the assessment of conservation conditions in a small earth dam","authors":"Luiz Filipe Caríssimo Soares ,&nbsp;Eduardo Antonio Gomes Marques ,&nbsp;Cibele Cláuver","doi":"10.1016/j.jappgeo.2026.106127","DOIUrl":"10.1016/j.jappgeo.2026.106127","url":null,"abstract":"<div><div>Assessing safety and conservation conditions in earth dams involves the investigation of phenomena that compromise their stability. In this regard, geophysical methods can be combined with direct investigations to enhance the efficiency of geotechnical studies, allowing faster data acquisition at relatively low cost. Therefore, this study aims to evaluate the conservation conditions of a small earth dam through the integrated interpretation of results obtained using the geophysical methods of Electrical Resistivity and Ground-Penetrating Radar, coupled with the results of grain size analyses of samples collected in situ. The results confirmed the efficiency of the proposed methodology, enabling assessment of features associated with the prolonged biological activity and surface water runoff. Among the identified geotechnical properties, a zone affected by the intense presence of ant nests and tree roots was detected, highlighting the need for corrective actions to maintain the structural integrity of the embankment.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"247 ","pages":"Article 106127"},"PeriodicalIF":2.1,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146081612","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}

{"title":"A proposed brittleness index model based on shale multicomponent digital cores","authors":"Haitao Wang ,&nbsp;Fuqiang Lai ,&nbsp;Min Wang ,&nbsp;Zhaohui Huang ,&nbsp;Zhangxiong Zhu ,&nbsp;Yuejiao Liu ,&nbsp;Xianfeng Tan ,&nbsp;Huaimin Dong ,&nbsp;Ye Yang","doi":"10.1016/j.jappgeo.2026.106110","DOIUrl":"10.1016/j.jappgeo.2026.106110","url":null,"abstract":"<div><div>The exploitation of organic shale reservoirs depends on the brittleness affected by lamination, fracture, porosity, and minerals. However, the existing brittleness index for petroleum only considers mineral types and requires comprehensive characterization. Therefore, a multicomponent model was constructed by inserting a planar fracture, planar lamination, and gas saturation model into a multimineral model using the Markov-chain Monte Carlo method. The elastic parameters were calculated using a finite element method, and the sensitivity of the parameters to the brittleness index defined by the Young's modulus and Poisson's ratio was determined using Morris screening and analytical hierarchy process methods. The investigation indicated that the development of brittle minerals and fracture porosity increased the brittleness index and, Young's modulus and decreased the Poisson's ratio, whereas the fracture width decreased the brittleness index, Gas saturation increases the brittleness index. A new comprehensive brittleness index was proposed in which the sensitivity decreased from the dip angle, azimuthal angle of fracture, dip angle of lamination, width and length of fracture, mineral types, width, and azimuthal angle of lamination to gas saturation. The proposed brittleness model was applied to a shale reservoir and is helpful in further identifying zones for hydraulic fracturing.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"246 ","pages":"Article 106110"},"PeriodicalIF":2.1,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146079200","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}

{"title":"Higher-order total-variation regularization methods for 3D inversion of gravity data","authors":"Mohammad Rezaie","doi":"10.1016/j.jappgeo.2026.106123","DOIUrl":"10.1016/j.jappgeo.2026.106123","url":null,"abstract":"<div><div>Inverting gravity data is an important geophysical method for imaging underground structures, but it naturally suffers from non-uniqueness. To produce solutions that make geological sense, some form of regularization is necessary. This paper presents an improved methodology for 3D gravity data inversion using higher-order total variation regularization techniques. Traditional first-order TV regularization has proved effective for blocky geological structures with sharp contrasts but often fails when the subsurface features are complex. We propose second and third-order TV regularization schemes that have the strengths of classical TV but provide much greater flexibility in handling more general geological contexts. The optimization problem including these higher-order regularization terms is solved by the reweighted regularized conjugate gradient algorithm, carefully addressing the parameters selection and focusing strategies. We demonstrate the effectiveness of our approach through synthetic examples, including a dipping dyke model and a multiple blocks scenario, where the higher-order TV methods give better performance for the reconstruction of subsurface structures compared to the minimum norm and first-order TV regularization. Then, the methodology was further validated using field data from the Thunderbird V-Ti-Fe deposit, Ontario, Canada, where the inversion of airborne gravity gradiometer data successfully revealed subsurface density distributions well-matched by the known geological and drilling data. The results illustrate that the higher-order TV regularization produces a more focused and geologically plausible model, especially in resolving complex structures at different levels. Current advances in inversion methodology are offering superior performance for applications in mineral exploration and geological studies.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"246 ","pages":"Article 106123"},"PeriodicalIF":2.1,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146079026","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}