Geophysical Prospecting最新文献

{"title":"A Data-Driven High-Resolution Imaging Based on the Cost-Effective Construction of Point-Spread Functions","authors":"Zhikang Zhou,&nbsp;Shaoyong Liu,&nbsp;Wenjun Ni,&nbsp;Zhe Yan,&nbsp;Hanming Gu,&nbsp;Bin Zhang","doi":"10.1111/1365-2478.70086","DOIUrl":"https://doi.org/10.1111/1365-2478.70086","url":null,"abstract":"<div>\u0000 \u0000 <p>Least-squares migration (LSM) is one of the most accurate imaging methods in seismic exploration. In recent years, image-domain LSM (ID-LSM) based on the approximated Hessian matrix has received widespread attention and development. How to effectively represent the Hessian matrix and implement the ID-LSM efficiently and stably remains challenging. This study proposes an efficient computation method for the Hessian matrix and develops a data-driven high-resolution imaging scheme to promote the application of LSM. Specifically, we first introduce the analytical expression of the Hessian matrix within the framework of inversion imaging, leveraging the sparsity of the Hessian matrix and using point-spread functions (PSFs) to approximate it. Then, considering the nonlinear characteristics of image-domain PSFs deconvolution, we employ deep learning to construct a data-driven imaging correction network. Finally, we incorporate features from the target data into the network, achieving efficient and faithful imaging of subsurface reflection coefficients. Through the computation cost analysis of PSFs construction, the developed method significantly reduces the computational costs, achieving only one-fourteenth of the modelling–migration method based on the wave equation. The synthetic and field data examples demonstrate the effectiveness of the proposed data-driven imaging scheme in both the spatial and wavenumber domains.</p>\u0000 </div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145272114","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":"Revisiting the Normalized Attenuation Coefficients of Plane P- and SV-Waves in Attenuative VTI Media and Their Effects on Parameter Inversion","authors":"Qi Hao,&nbsp;Stewart Greenhalgh,&nbsp;Xingguo Huang","doi":"10.1111/1365-2478.70088","DOIUrl":"https://doi.org/10.1111/1365-2478.70088","url":null,"abstract":"<div>\u0000 \u0000 <p>Analytical formulae for P- and SV-wave normalized attenuation coefficients play a key role in attenuation anisotropy parameter estimation in dissipative transversely isotropic media with a vertical symmetry axis. We revisit approximate formulae for the P- and SV-wave normalized attenuation coefficients. We use perturbation theory to derive accurate formulae for P- and SV-waves in such media. The proposed formulae can reduce to simple expressions for attenuative elliptical anisotropic media and isotropic media. From the perturbation-based formulae, we obtain the linearized formulae, the second-order formulae and the fractional formulae. We use numerical examples to test the accuracy of the proposed formulae and implement the perturbation-based formulae and the second-order formulae in an inversion scheme to estimate the attenuation anisotropy parameters. From the numerical examples, we analyse the validity of the approximate formulae in computing the normalized attenuation coefficients and attenuation anisotropy parameter estimation.</p></div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145272111","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":"Joint Inversion of Electromagnetic and Direct Current Resistivity Data Using Trust Regions. Application to Uranium Exploration in the Athabasca Basin","authors":"Ali Mohand-Said,&nbsp;Guy Marquis,&nbsp;Serge Sambolian,&nbsp;Jean-François Girard,&nbsp;Grant Harrison,&nbsp;Elodie Williard","doi":"10.1111/1365-2478.70079","DOIUrl":"https://doi.org/10.1111/1365-2478.70079","url":null,"abstract":"<p>The Athabasca Basin (Saskatchewan, Canada) is a world-class uranium mining province hosting high-grade high-tonnage deposits. Electromagnetic data and direct current resistivity data are essential tools to detect deep geoelectric structures associated with mineralization. Both methods are sensitive to electrical resistivity but highlight different structures. On the one side, electromagnetic methods reveal deeply buried, highly conductive graphitic structures. On the other side, direct current resistivity methods reveal milder contrasts of resistivity at shallower depths. We are here exploring the benefits that can be expected from two-dimensional joint inversion of electromagnetic and direct current resistivity data for the exploration of unconformity-related uranium deposits of the Athabasca Basin. Our methodology is recovering a single resistivity model to fit both datasets. We used a trust-region globalization approach to regularize the local minimization sub-problems, thus avoiding the task of regularization parameter tuning. Several tests are first conducted on synthetic models. These tests show that stand-alone electromagnetic inversions are able to recover the position of conductive plates, but their geometry remains uncertain. On stand-alone direct current resistivity inversions, the layered background is recovered, as well as smeared anomalies of resistivity associated with graphitic conductors. Whenever a conductive halo overlies a conductive plate, the wide anomaly associated with the plate appears more conductive and slightly shallower but the conductive plate and the halo cannot be distinguished. In the presence of two closely spaced conductors, the conductive anomaly appears more conductive and wider, so that they cannot be distinguished. On stand-alone electromagnetic inversions, however, their separation is clear, but electromagnetic measurements are blind to alteration halos. Joint inversions give the most reliable models. Both the resistive background and the conductive plates are recovered. A better constrained background allows to recover more contrasted plates. Synthetic tests allowed us to confirm the potential to recover the footprint of a hectometric-scale conductor overlying a plate using joint inversion, where both stand-alone inversions failed. Following these synthetic tests, we present an application of our methodology to a dataset from the Waterbury–Cigar Lake area. Joint inversion allows to recover a geoelectric model reconciling both datasets. The model shows conductors better constrained below the depth of unconformity, allowing for interpretations of resistivity variations above them.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70079","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145272113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 3D Shallow Velocity Model Building Method Using the Joint Inversion of First-Arrival and Reflection Traveltimes Constrained by Well Data","authors":"Wanli He,&nbsp;Jianzhong Zhang,&nbsp;Fei Ma,&nbsp;Junjie Sun,&nbsp;Jie Chen","doi":"10.1111/1365-2478.70089","DOIUrl":"https://doi.org/10.1111/1365-2478.70089","url":null,"abstract":"<div>\u0000 \u0000 <p>Prestack depth migration requires a velocity model that extends from the surface through shallow to deep layers. Generally, the shallow velocity model is built using first-arrival wave, under which the velocity model is built from reflected wave. These two models are integrated to form a continuous velocity model spanning from the surface to deep layers. Conventional shallow velocity model building methods are restricted by non-uniqueness of inversion, limited inversion depth and poorly defined reflection interface, which hinders their integration with deeper reflection-derived velocity models. Errors in the shallow velocity model can compromise the imaging quality of mid-deep. In this article, we propose a 3D shallow velocity model building method using the joint inversion of first-arrival and reflection traveltimes constrained by well data. This approach enables simultaneous inversion of velocity and reflection interfaces, thereby facilitating the integration of shallow and mid-deep velocity models. Combining the first-arrival and reflected waves enhances ray coverage angles and folds. By constraining the inversion for velocity and reflection interface with logging velocity and drilling depth, respectively, the method effectively mitigates the non-uniqueness of inversion, thereby improving the accuracy of shallow velocity model. The inverted reflection interface can also be used for integration of shallow velocity model and its underlying velocity model. The theoretical model test proves the feasibility of the method, and the field data application verifies the effectiveness of the method.</p>\u0000 </div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145272115","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":"Evaluating Elastic Parameters of a CO2 Plume Using Model-Based and Sparse Layer Reflectivity Inversion of Time-Lapse Seismic Data: A Case Study","authors":"G. Hema,&nbsp;S. P. Maurya,&nbsp;Nitin Verma,&nbsp;Ravi Kant,&nbsp;Ajay P. Singh,&nbsp;Brijesh Kumar,&nbsp;Raghav Singh,&nbsp;K. H. Singh","doi":"10.1111/1365-2478.70085","DOIUrl":"https://doi.org/10.1111/1365-2478.70085","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 &lt;p&gt;The objective of this research is to estimate the elastic properties of the CO&lt;sub&gt;2&lt;/sub&gt; plume in the Sleipner field and perform a comparative analysis of model-based inversion (MBI) and sparse layer reflectivity (SLR) inversion techniques. MBI is relatively old method, whereas SLR is relatively new method for seismic inversion. Model-based seismic inversion is a well-established deterministic inversion technique that iteratively minimizes the misfit between observed and modelled seismic data. In contrast, SLR inversion is designed to identify and analyse the reflectivity of thin subsurface layers by emphasizing sparsity in the reflectivity sequence. This study utilizes a set of time-lapse seismic angle stack data from the Sleipner field, comprising a 1994 pre-injection baseline and a 1999 post-injection monitor survey, following the injection of 2.35 million tons of CO&lt;sub&gt;2&lt;/sub&gt;. These angle stacks were used to generate P-wave and S-wave reflectivity using the two-term Fatti amplitude versus offset (AVO) equation, which was then further utilized in the inversion process to estimate the elastic parameters. Acoustic and shear impedance (SI) were derived using MBI and SLR to evaluate their strengths, limitations, computational efficiency and adaptability to geological changes. In the CO&lt;sub&gt;2&lt;/sub&gt;-injected zone, acoustic impedance values were observed between 2000 and 2400 m/s g/cm&lt;sup&gt;3&lt;/sup&gt;, whereas SI values ranged from 100 to 400 m/s g/cm&lt;sup&gt;3&lt;/sup&gt;. Our findings suggest that overall, MBI produces sharper and more reliable imaging across the entire seismic section. For P-impedance, MBI yielded correlation values of 0.980 with an error of 0.137 in 1994 and 0.989 with an error of 0.141 in 1999 datasets, whereas SLR showed higher correlation at the well location 0.997 with an error of 0.073 in 1994 and 0.998 with an error of 0.061 in 1999. For S-impedance, MBI achieved correlation values of 0.860 with an error of 0.650 in 1994 and 0.974 with an error of 0.265 in 1999 datasets. In comparison, SLR produced a correlation of 0.995 with an error of 0.072 in 1994 and 0.951 with an error of 0.370 in 1999 datasets at the well location. However, similar to the P-impedance case, whereas SLR performed well at the well location, its application to the full seismic volume resulted in reduced performance, characterized by noisier results and longer processing time. A comparative evaluation of MBI and SLR indicates that MBI offers greater efficiency, simpler implementation and faster computational performance. As a result, the impedance outputs obtained from MBI were subsequently converted into density, P-wave velocity and S-wave velocity using empirical relationships derived from well log data. In the seismic volumes, a significant change in the reservoir's elastic properties was observed in the CO&lt;sub&gt;2&lt;/sub&gt;-saturated zone, compared to the Utsira Formation, which serves as the reservoir into which CO&lt;sub&gt;2&lt;/sub&gt; has been inj","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145271946","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":"An Improved Equivalent Circuit for Electric Field Sensors in Geophysical Exploration","authors":"Thomas Kalscheuer,&nbsp;Uwe Zimmermann,&nbsp;Henrik Sparr,&nbsp;Anton Palm Ekspong,&nbsp;Alexander Lindblad","doi":"10.1111/1365-2478.70047","DOIUrl":"https://doi.org/10.1111/1365-2478.70047","url":null,"abstract":"&lt;p&gt;In electromagnetic measurements, electric field sensors consist of two halves, with remote electrodes of negative and positive polarity coupled through wires and low pass filters to the differential inputs of an analogue-to-digital converter; the electrical ground of the analogue-to-digital converter is connected to the ground through a reference electrode. We present, analyse and evaluate improved equivalent circuits for such electric field sensors. This serves to identify the maximum contact resistances of the electrodes for which the recorded voltages are unaffected by system response effects over a given frequency range. In the first step, we verify a new equivalent circuit for one half of an electric field sensor by comparison to a previously published equivalent circuit. In contrast to the latter, our equivalent circuit accounts for the spatial variability of the electric field along an extended sensor cable, the finite impedance of the receiver input stage, the non-zero contact resistance of the reference electrode and residual cable on a winch. Furthermore, the cable is characterised by its resistance, self-inductance and capacitance to the ground and the ionosphere or the borehole fluid. Compared to the absolute value of the voltage, our results show that the system response affects the phase of the voltage at lower frequencies. In the next step, we develop an equivalent circuit for a complete electric field sensor connecting two sensor halves to an analogue-to-digital converter. We study both symmetric and asymmetric set-ups with identical and differing cable lengths, respectively, of the sensor halves. Over the whole frequency range, the amplitude gets the lower, the higher the sum of contact resistances of the remote electrodes is. In contrast, the phase is distorted only at higher frequencies. Generally, the contact resistance of the central reference electrode has little effect. For symmetric sensors, of the combinations of contact resistances of the remote electrodes that have the same sum, it is the combination of identical contact resistances that shows the lowest distortion. The distortion owing to different contact resistances of the remote electrodes is only slight and mostly in the amplitude at high frequencies. For asymmetric sensors, the benefits of using a differential analogue-to-digital converter input are no longer exploited. For instance, flipping the contact resistances of the remote electrodes leads to different responses at high frequencies. In borehole applications, it is of particular importance to account for the spatial variability of the electric field due to the skin effect, field propagation and the curvature of the borehole track. We consider an extended electric field sensor that is placed in a borehole at an inclination of &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;45&lt;/mn&gt;\u0000 &lt;msup&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 ","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70047","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145224080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low-Frequency Extrapolation by Deep-Learning for Cross-Well Full-Waveform Inversion – Case Study From the Aquistore \u0000 \u0000 \u0000 CO\u0000 2\u0000 \u0000 $rm CO_{2}$\u0000 Storage Site","authors":"Amir Mardan,&nbsp;Don White","doi":"10.1111/1365-2478.70081","DOIUrl":"https://doi.org/10.1111/1365-2478.70081","url":null,"abstract":"<p>Full-waveform inversion (FWI) of seismic data is a powerful method for estimating high-resolution models of the subsurface. An accurate initial model and low-frequency data are necessary to avoid cycle skipping and perform a successful FWI. In the absence of this information, FWI is likely to fail due to convergence in local misfit minima. With the recent advancements in artificial intelligence, studies have shown that absent low-frequency data can be extrapolated using deep learning (DL). These studies have been mostly focused on surface seismic data whose frequency content is different from cross-well data. In this study, we assess the use of DL for low-frequency extrapolation for a cross-well survey that was done at the Aquistore <span></span><math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>CO</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 <annotation>$rm CO_{2}$</annotation>\u0000 </semantics></math> storage site in Saskatchewan. This assessment includes both numerical and field data examples. We extrapolate the low frequencies to increase the bandwidth of the acquired data at the Aquistore site and perform FWI. We evaluate the efficiency of this method by comparing the results with obtained velocity models from the conventional multiscale FWI. Our results for the Aquistore data show that the proposed strategy leads to an accuracy improvement of 39% and 20% in the model and data domains, respectively.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145146338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved One-Way Reflection Waveform Inversion and Strategies for Optimal Offset Selection","authors":"Siamak Abolhassani,&nbsp;Dirk Jacob Verschuur","doi":"10.1111/1365-2478.70062","DOIUrl":"https://doi.org/10.1111/1365-2478.70062","url":null,"abstract":"<p>Conventional reflection waveform inversion solves a two-parameter seismic inverse problem alternately for subsurface reflectivity and acoustic background velocity as the model parameters. It seeks to reconstruct a low-wavenumber velocity model of the subsurface from pure reflection data cyclically, through alternating migration and tomography loops, such that the remodelled data fits the observed data. Low-resolution seismic images with unpreserved amplitudes, full-wave inconsistency in the short-offset data and cycle skipping in the long-offset are perceived as the main reasons for suboptimal tomographic updates and slow convergence in conventional reflection waveform inversion. In the context of one-way reflection waveform inversion, this paper addresses the listed limitations through four main components. First, it augments one-way reflection waveform inversion with a computationally affordable preconditioned least-squares wave equation migration algorithm to ensure high-resolution reflectors with preserved amplitudes. Second, the paper verifies how well the full-wave consistency condition in the short-offset data is satisfied in one-way reflection waveform inversion and suggests muting inconsistent short-offset residual waveforms in the tomography loop to attenuate their adverse imprint. Third, the paper suggests extending the migration offset beyond short offsets to improve both the illumination and the signal-to-noise ratio of the reflectors. Fourth, the paper presents a data-selection algorithm to exclude the damaging effect of the cycle-skipped long-offset data in the tomography loop. The effectiveness of the proposed one-way reflection waveform inversion algorithm is finally validated through three numerical examples, demonstrating its capability to recover high-fidelity tomograms.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forward Modelling of Electrical Resistivity and Induced Polarization Using the Spectral-Infinite-Element Method","authors":"Kiana Damavandi,&nbsp;Hom Nath Gharti","doi":"10.1111/1365-2478.70080","DOIUrl":"https://doi.org/10.1111/1365-2478.70080","url":null,"abstract":"<p>Accurate and efficient modelling of subsurface electrical properties is critical for a wide range of applications, including mineral exploration, environmental studies and hydrogeological investigations. Traditional numerical approaches often use low-order discretization and impose artificial boundary conditions to approximate the unbounded spatial domain. These approximations can lead to inaccuracies and computational inefficiency, particularly in geologically complex environments. In this study, we present a spectral-infinite-element method (SIEM) for forward modelling of electrical resistivity and induced polarization. The approach couples high-order spectral elements within the finite domain with a single outer layer of mapped infinite elements, enabling precise representation of far-field boundary conditions. To achieve optimal numerical performance, we employ two distinct quadrature schemes: Gauss–Legendre–Lobatto quadrature for the spectral elements and Gauss–Radau quadrature for the infinite elements. We first verify the accuracy of our method by comparing the computed electric potential from a buried charged block with direct numerical integration. We conducted a convergence study by refining the mesh and increasing the order of the interpolation polynomials. To further evaluate the robustness of SIEM, we benchmark its results for a layered earth model against an analytical solution and an open-source Python-based geophysical modelling library, SimPEG. The comparisons demonstrate the accuracy, convergence and efficiency of SIEM. Finally, we apply SIEM to a complex heterogeneous conductivity model incorporating topography, generating apparent resistivity and chargeability pseudo-sections to illustrate its practical applicability under realistic survey conditions.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraining Contact-Depth Solutions Through the Enhanced Horizontal Gradient Amplitude","authors":"Luan Thanh Pham,&nbsp;Saulo Pomponet Oliveira,&nbsp;Erdinc Oksum,&nbsp;Hanbing Ai,&nbsp;Fabiana de Fátima Giacomini","doi":"10.1111/1365-2478.70078","DOIUrl":"https://doi.org/10.1111/1365-2478.70078","url":null,"abstract":"<div>\u0000 \u0000 <p>Accurate depth estimation is crucial for the quantitative interpretation of magnetic anomalies, which plays a significant role in geological mapping, mineral exploration and subsurface investigations. Traditional depth estimation techniques, such as the contact-depth (CD) and tilt-depth (TD) methods, often suffer from the generation of spurious solutions, especially when applied to complex geological environments. To address this, we propose an enhanced depth estimation technique, namely, the located contact-depth (LCD) method that integrates the CD technique with the enhanced horizontal gradient amplitude (EHGA). By utilizing points near the peaks of EHGA, a mask is generated to constrain the solutions from the CD method, effectively eliminating false solutions. Furthermore, a stable finite-difference technique for calculating vertical derivatives is used to improve the robustness and stability of the outputs. The proposed technique is tested on synthetic data, both with and without noise, as well as on real aeromagnetic data from the Galinge Fe-polymetallic deposit (China). The results demonstrate that our method provides depth estimates with improved reliability and accuracy compared to traditional methods, reducing the number of spurious solutions and enhancing precision around source boundaries. The result from the real example is in good agreement with known structures, highlighting the potential for deep mineral exploration in the Galinge Fe-polymetallic deposit.</p>\u0000 </div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145022016","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}