Journal of Applied Geophysics最新文献

{"title":"Feasibility study of telluric magnetic field frequency selection method in groundwater exploration","authors":"Tianchun Yang ,&nbsp;Debing Zhu ,&nbsp;Yawar Hussain ,&nbsp;Rui Huang ,&nbsp;Qilang Yu ,&nbsp;Qijun Ding","doi":"10.1016/j.jappgeo.2024.105608","DOIUrl":"10.1016/j.jappgeo.2024.105608","url":null,"abstract":"<div><div>Over the years, scholars have made significant contributions in the development of various electric pulse of a natural field methods, collectively referred to as frequency selection method (FSM). The methods still lacking the satisfactory exploratory theoretical studies for interpreting the results effectively. In a previous study, authors concluded that results obtained at several frequencies with both telluric electrical field frequency selection method (TEFSM) and telluric magnetic field frequency selection method (TMFSM) are affected by static shift effects. The present study is dedicated to the feasibility of the methods in groundwater exploration of karst aquifer applying two-dimensional forward simulations and field measurements. In the first stage, utilizing the magnetotellurics (MT) 2D forward modeling theory, authors computed the surface horizontal electric <em>E</em>_<em>x</em> and magnetic <em>H</em>_<em>x</em> field components along the survey line in both telluric magnetic (TM) and telluric electric (TE) polarization modes. Secondly, TEFSM was used where the measured curves of electric field at different frequencies were found well synchronized in depicting the abnormal position. Further, the field testing of audio-frequency magnetotellurics (AMT) conducted with V8 electric acquisition system considerably suppressed the interferences from anthropogenic noise sources. The synchronicity of magnetic field component curves at different frequencies was worse than that of electric field component. The simulation results indicated that the component <em>E</em>_<em>x</em> exhibited significantly high-value anomalies over high resistance bodies, whereas <em>E</em>_<em>y</em> and <em>H</em>_<em>x</em> components did not show clear anomalies. All three components displayed apparent anomalies for conductive bodies. Theoretically, TMFSM is a feasible approach for exploring shallow conductive abnormal bodies, although the component <em>H</em>_<em>x</em> is susceptible to external interference in practical applications. Therefore, designing specialized magnetic sensors with strong anti-interference capability and high-accuracy is a significant step towards achieving the satisfactory results.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105608"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143135603","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":"Analysis of 3D induced polarization effects of SOTEM","authors":"Wanting Song ,&nbsp;Wen Chen ,&nbsp;Yanbo Wang ,&nbsp;Weiying Chen","doi":"10.1016/j.jappgeo.2024.105613","DOIUrl":"10.1016/j.jappgeo.2024.105613","url":null,"abstract":"<div><div>The short-offset grounded-wire transient electromagnetic method (SOTEM) is characterized by observations conducted in the near-source region. When a polarizable medium is present, significant polarization field responses can be detected. Existing studies have been limited to 1D models, which have not elucidated the characteristics of polarization and induction fields for 3D polarization bodies. This paper employs the Comsol platform to construct and solve a 3D model in the frequency domain. The frequency-domain response is then transformed into a time-domain step response, achieving 3D finite element forward modeling of SOTEM with induced polarization (IP) effects. The accuracy of the 3D simulation is validated. We calculated basic 3D models containing polarized layers as well as typical high- and low-resistivity polarization bodies, analyzing the impact of IP effects on the SOTEM horizontal electric field Ex and vertical magnetic field Hz responses. It was found that the sign of the total field formed by the induced current and the polarization current determines the sign reversal phenomenon. Both the Ex and Hz components respond well to low-resistivity polarization bodies, while the Ex component demonstrates significantly better detection capabilities for high-resistivity polarization bodies. This paper provides a method for time-domain electromagnetic 3D simulation considering IP effects, offering valuable insights for advancing the application of SOTEM with IP effects in the exploration of metallic mineral resources and groundwater.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105613"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136392","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":"Non-destructive GPR signal processing technique for thickness estimation of pavement, coal and ice layers: A review","authors":"Shweta B. Thomas ,&nbsp;Sangeetha Subbaraj ,&nbsp;Deepika Rani Sona ,&nbsp;Benedict Thomas","doi":"10.1016/j.jappgeo.2024.105601","DOIUrl":"10.1016/j.jappgeo.2024.105601","url":null,"abstract":"<div><div>In recent years, there has been a significant surge in the utilization of Ground Penetrating Radar (GPR) for measuring the thickness of subsurface layers, and researchers in this field have paid close attention to it. GPR enables users to achieve greater precision in evaluating the quality and condition of underground materials. The traditional methods used to measure the thickness of underground layers are time-consuming, hard to conduct and not economical. GPR is one of the most recommended non-destructive geophysical methods for routine subsurface inspections. This article is intended to highlight the application of GPR for thickness estimation of distinct materials such as, pavement, ice and coal layers and novel non-destructive testing (NDT) techniques adopted recently for thickness estimation. This article presents an overview of Ground Penetrating Radar (GPR) methodologies for layer thickness estimation, encompassing their advantages, disadvantages, and recent research findings. By synthesizing existing literature, the potential applications of GPR while addressing its inherent limitations are illustrated here. Furthermore, practical recommendations are provided to enhance the effectiveness of GPR-based layer thickness estimation techniques.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105601"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097303","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":"Influence of grounded source geometry and terrain on the semi-airborne transient electromagnetic response from 3D simulation data","authors":"Jinjing Shi ,&nbsp;Xin Wu ,&nbsp;Yanbo Wang ,&nbsp;Yang Zhao","doi":"10.1016/j.jappgeo.2024.105619","DOIUrl":"10.1016/j.jappgeo.2024.105619","url":null,"abstract":"<div><div>The Semi-Airborne Transient Electromagnetic (SATEM) method utilizes a grounded source and airborne receivers, making it well-suited for high-precision, rapid, and deep electromagnetic surveying in complex terrain. Typically, the grounded source is assumed to be a simple linear form in existing inversions. However, in practice, the long grounded source can be bent or undulating due to the influence of terrain, resulting in significant deviations from the idealized straight-line model. Prior studies have investigated the effects of source bending in the horizontal plane or undulation in the vertical elevation separately. This paper provides a comprehensive analysis of the combined influence of complex terrain on the spatial deployment of the grounded source. Through a thorough examination of the superposition effects of multiple unfavorable factors, the study clarifies the spatio-temporal distribution of the complex source deployment pattern on the SATEM response. The findings provide a basis for confirming the reliability of inversion results and offer suggestions for improving field survey specifications for the SATEM method.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105619"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143092045","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":"Time-lapse amplitude variation with offset difference inversion based on the reformulated Biot-Squirt model","authors":"Longxiao Zhi,&nbsp;Xiaochun Lv,&nbsp;Xuwei Pan,&nbsp;Shuo Zhang","doi":"10.1016/j.jappgeo.2024.105588","DOIUrl":"10.1016/j.jappgeo.2024.105588","url":null,"abstract":"<div><div>Time-lapse AVO (Amplitude variation with offset) inversion is a significant technique for the estimation of dynamic reservoir changes. The main theoretical foundation is Zoeppritz equations in single-phase media. At present, there are studies on the inversion method of using Biot's theory. Although it has some improvements in accuracy compared with the method of using Zoeppritz equations, the squirt-flow mechanism is not considered. Furthermore, the precision of difference data equations still needs to be improved in difference inversion. In view of the above problems, the reformulated BISQ (Biot-Squirt) model is introduced into the inversion, and the iterative optimization is used to increase the precision of difference data equations continually in this paper. First, we derive the difference data equations about the reservoir-parameter changes. The reformulated BISQ model is applied, and can describe the characteristics of P-wave reflection accurately and expediently. Secondly, the objective function about the reservoir-parameter changes is constructed. The Bayesian theory and the model smoothing constraint are used, and are helpful to obtain accurate and stable solutions. Thirdly, we derive the equation for estimating the reservoir-parameter changes, and the inversion is iterative for the continuous improvement of accuracy. The difference inversion method is applied, and is helpful to enhance the data repeatability and reduce the calculation amount. Finally, synthetic and real data are applied for the inversion and testing to prove the effectiveness and feasibility of the method.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105588"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097302","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 novel geodetic approach for determination the marine internal gravity: The “seawater layer” method","authors":"Ganghua Ni ,&nbsp;Zhengtao Wang ,&nbsp;Wenbin Shen ,&nbsp;Cong Liu ,&nbsp;Nengfang Chao","doi":"10.1016/j.jappgeo.2025.105636","DOIUrl":"10.1016/j.jappgeo.2025.105636","url":null,"abstract":"<div><div>The ocean, especially the deep ocean, as an undeveloped earth space and resource, plays an increasingly prominent role in energy security and scientific development. Deep sea exploration is a strategic need for the construction of marine science and technology. The internal gravity field of the ocean is important in geophysics, geodesy, and oceanography. Classical physical geodesy mainly focuses on the solution of the geodetic boundary value problem, which is usually given by the theorems of Stokes and Molodenskii. Solving the internal gravity field of the ocean is a problem of solving the internal potential of the earth, to which theoretical methods of classical geodesy cannot be applied. To solve this limitation, the concept of “seawater layer” is introduced to calculate the internal ocean gravity. Taking the South China Sea as the experimental area, using high-resolution data of the Digital Earth Model, combined with Newton's integration method and spherical harmonic expansion algorithm, the internal ocean gravity field in the South China Sea was determined: The accuracy of the “seawater layer” method to remove - restore the ocean surface gravity is evaluated and the difference RMS is 4.06mGal at the depth of 500 m, 9.56mGal at 1000 m, 5.05mGal at 2000 m, 8.38mGal at 3000 m, and 7.01mGal at 4000 m, and the entire regional difference RMS error is 7.57mGal, indicated good consistency and the reliability; Based on this theory, the 3D distribution of the South China Sea internal Gravity Field was obtained by combining sea water density/depth and sea-surface/seabed gravity data, providing a theoretical basis and algorithm model for seabed gravity measurement and underwater navigation.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105636"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143097101","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":"Common-mode noise separation in distributed acoustic sensing vertical seismic profile data: A self-supervised deep learning approach with enhanced blind network","authors":"Yeonghyeon Son ,&nbsp;Byoungjoon Yoon ,&nbsp;Kitaek Hong ,&nbsp;Myung-hun Lee ,&nbsp;Juan Lee ,&nbsp;Sang-Jin Choi","doi":"10.1016/j.jappgeo.2025.105634","DOIUrl":"10.1016/j.jappgeo.2025.105634","url":null,"abstract":"<div><div>Distributed fiber-optic acoustic sensing (DAS) has emerged as a transformative technology for seismic exploration, offering adaptability, environmental sustainability and cost-efficiency, especially for vertical seismic profile (VSP) acquisition. However, practical applications face the challenges of diverse random noise, incoherent background noise, and weak target signals. Conventional supervised learning methods for noise separation are based on noise-free labels, which limits their applicability in seismic exploration. To address this gap, a novel label-free self-supervised learning approach, called dual-model self-supervised selective learning (dSSSL) is proposed to separate common-mode noise, specifically coherent noise typical of DAS-VSP data, from the desired signals. Our methodology leverages blind horizontal networks (BHNs) to mitigate the common-mode noise, and overcomes the identity mapping challenges inherent in U-Net with the introduction of the blind spot network (BSN). The effectiveness of our method is validated with synthetic DAS-VSP and field data from Janghang-ri, showing that the signal recovery is superior compared to conventional methods. This approach is promising for improving seismic data processing and interpretation in distributed fiber-optic acoustic sensing applications, particularly for vertical seismic profile acquisition.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105634"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096570","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":"Practice and theoretical analysis of ground penetrating radar in voids detection of urban underground pipe-jacking","authors":"Fengming Hu ,&nbsp;Tianchun Yang ,&nbsp;Theophilus Aanuoluwa Adagunodo ,&nbsp;Debing Zhu ,&nbsp;Rui Huang","doi":"10.1016/j.jappgeo.2025.105639","DOIUrl":"10.1016/j.jappgeo.2025.105639","url":null,"abstract":"<div><div>Pipe-jacking construction technology has become more prevalent with the development of urbanization. At the same time, non-destructive detection of the compactness around the pipe-jacking is a necessary step in the pipe-jacking engineering. Therefore, the present study intends to explore the non-destructive detection of pipe-jacking quality by using ground penetrating radar. Ground penetrating radar can also be called GPR for short, and it plays an irreplaceable role in our life through its efficient and nondestructive detection function. In the study, void models for plastic jacking pipes, reinforced concrete jacking pipes, and steel jacking pipes were constructed, and forward simulations of ground penetrating radar were conducted using the two-dimensional finite element method to investigate the parameter influences brought about by seasonal changes and the shape of the voids; furthermore, combined with the sewage jacking pipe project in Xiangtan City, Hunan Province, practical detection and experimental research on reinforced concrete jacking pipes and steel jacking pipes are carried out using ground penetrating radar. The research results indicate that ground penetrating radar is feasible for detecting the density conditions around cement jacking pipes, plastic jacking pipes, and reinforced concrete jacking pipes. However, when detecting the void conditions around steel jacking pipes, strong multiple reflections occur between the radar antenna and the pipe wall, making it impossible to achieve the goal of detecting the density behind the jacking pipe. Therefore, future research is needed to develop new methods and technologies for assessing the construction quality of steel jacking pipes.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105639"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096575","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":"Dynamic response of a circular lined tunnel and type-III crack in the presence of a semicircular canyon embedded in an anisotropic half-space subjected to SH wave","authors":"Debao Guo,&nbsp;Zailin Yang,&nbsp;Jinlai Bian,&nbsp;Yunqiu Song,&nbsp;Yong Yang","doi":"10.1016/j.jappgeo.2024.105614","DOIUrl":"10.1016/j.jappgeo.2024.105614","url":null,"abstract":"<div><div>In this study, the dynamic interactions between a surface semicircular canyon in an anisotropic geology and a circular lined tunnel and type-III crack buried at an arbitrary location below under the excitation of anti-plane shear horizontal (SH) waves are investigated. The wave fields and the stress fields in the half-space are efficiently constructed using the wave function expansion method, the complex function method and the mirror image method. The scattered waves generated by crack are constructed based on Green function and “crack cutting” technique. The position correction coefficient is introduced in practical applications, which perfectly solves the problem of mirror asymmetry of the scattered wave field in a half-space anisotropic medium. And deriving the surface displacement amplitude (|<em>W</em>|) containing the semicircular canyon, the dynamic stress concentration factor (DSCF) along the tunnel boundary and the dynamic stress intensity factor (DSIF) at the tip of the crack. The correctness of the method is verified by degenerating it to a classical analytical solution. Finally, the effects of the anisotropic strength of the geology, the tunnel size and the location of the fissure as well as the incident angle and wave number of the SH wave on the |<em>W</em>|, DSCF and DSIF are analyzed by numerical calculations in both the frequency and time domains. The results show that the anisotropic strength of the geology and the surrounding media defects have a large influence on the dynamic response of both surface and subsurface structures, and that sufficient attention should be paid to the development and design of near-surface tunnels in canyon or basin terrain.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105614"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136393","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":"Research on the response of different flight modes under concave and convex terrain by Semi-Airborne Transient Electromagnetic Method (SATEM)","authors":"Bin Xie,&nbsp;Yingying Zhang,&nbsp;Xinyu Wu,&nbsp;Wenyu Wu","doi":"10.1016/j.jappgeo.2024.105576","DOIUrl":"10.1016/j.jappgeo.2024.105576","url":null,"abstract":"<div><div>With the development and utilization of various mineral resources in horizontal terrain areas gradually becoming saturated, the study of transient electromagnetic method has gradually shifted from flat terrain areas to complex fluctuating and high altitude areas. Due to the characteristics of transmitting source on the ground and receiving point in the air, the Semi-Airborne transient electromagnetic method (SATEM) has advantages such as superior working efficiency, large exploration depth and higher signal-to-noise ratio of collected signals. At present, there are few researches on the influence of the flight mode of the UAV on the collected data. In this paper, the concave terrain and convex terrain are described by using unstructured tetrahedral mesh, and the response of terrain model is calculated. Then the terrain response under different flight modes has been researched and analyzed systematically. The corresponding relative error graph is obtained and compared to summarize the law. Through simulation with different influence parameters, it is found that when the flight mode of the UAV is the same altitude, the SATEM response is less affected by the fluctuating terrain, and when the flight mode of the UAV is along the terrain, the SATEM response is more affected by the fluctuating terrain. The study of the response of UAV to the undulating terrain under different flight modes can provide a reference for the processing and interpretation of SATEM data in the undulating terrain region.</div></div>","PeriodicalId":54882,"journal":{"name":"Journal of Applied Geophysics","volume":"233 ","pages":"Article 105576"},"PeriodicalIF":2.2,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143096933","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}