Geophysical Prospecting最新文献

{"title":"Prediction of anisotropic coalbed methane reservoir brittleness index based on rock physics modelling","authors":"Zhaoji Zhang,&nbsp;Fei Gong,&nbsp;Guangui Zou,&nbsp;Guowei Zhu,&nbsp;Wei Liu,&nbsp;Hao Chen","doi":"10.1111/1365-2478.70022","DOIUrl":"https://doi.org/10.1111/1365-2478.70022","url":null,"abstract":"<p>The brittleness index is a significant indicator for forecasting the characteristics of coalbed methane reservoirs. However, the brittleness index of coalbed methane reservoirs is susceptible to a number of influencing factors, including the pore structure, coalbed methane content and pore fluid. Moreover, coalbed methane reservoirs are characterized by vertical transverse isotropy anisotropy, which presents a significant challenge to the accurate prediction of brittleness. Accordingly, this paper presents a new rock physics model for coalbed methane reservoirs, based on experimental test data obtained from coal samples. This model considers the vertical transverse isotropy anisotropy characteristics of coalbed methane reservoirs and the influence of pore structure, adsorbed gas and pore fluid in coal. The accuracy of the model is corroborated by the results of the experimental tests. The model predictions indicate that organic matter and clay content exert a greater influence than the stratification indicator factor. The impact of content is smaller than that of pore structure, and the influence of coalbed methane increases following water saturation. The model may be employed to forecast the elastic anisotropy and brittleness index of vertical transverse isotropy-type coalbed methane reservoirs. The inversion results of the logging data indicate that the brittleness index of coalbed methane reservoirs exhibits some variation in different directions and the brittleness index is greater along the bedding direction. The study assists in elucidating the interrelationship between the rock physical parameters of coalbed methane reservoirs and the brittleness index of coal seams, thereby furnishing a basis for anticipating the anisotropic sweet spot in coalbed methane reservoirs.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1488-1509"},"PeriodicalIF":1.8,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143949724","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":"Determining structural boundaries using blocky magnetotelluric data inversion","authors":"Kaijun Xu,&nbsp;Yaoguo Li","doi":"10.1111/1365-2478.70018","DOIUrl":"https://doi.org/10.1111/1365-2478.70018","url":null,"abstract":"<div>\u0000 \u0000 <p>The magnetotelluric method has large depths of investigation and can provide important structural information in many exploration problems. The one-dimensional magnetotelluric inversion also has been applied to extract boundary information and provide the constraints for the interpretation of complementary datasets. Traditional smooth inversion based on the <span></span><math>\u0000 <semantics>\u0000 <msub>\u0000 <mi>L</mi>\u0000 <mn>2</mn>\u0000 </msub>\u0000 <annotation>${L}_2$</annotation>\u0000 </semantics></math> norm only provides a single smooth model that it is difficult to detect the location of the geological boundary. Trans-dimensional inversion provides an effective means to determine the boundaries with uncertainty quantification but incurs significant computational costs. We present an efficient method to detect distinct interfaces from one-dimensional blocky magnetotelluric inversions using an Ekblom norm. The method leverages the Ekblom norm to assess the change in the recovered resistivity model with the threshold parameter as a means to delineate the significant boundaries in the subsurface. The threshold parameter specific to the Ekblom-norm inversion is then used to probe the variability of the inversion to obtain a more robust interface detection. Once the interfaces are detected, we calculate the average resistivity value between detected interfaces to form a final conductivity model. As a demonstration, we apply this method to a synthetic example and the field data from East Tennant in Australia. The results show that the method is effective in obtaining boundaries.</p></div>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1456-1470"},"PeriodicalIF":1.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950280","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":"Stable Q-compensated viscoelastic reverse-time migration based on the modified fractional Laplacian wave equations","authors":"Haiqiang Tang,&nbsp;Jianping Huang,&nbsp;Qiang Mao,&nbsp;Xinru Mu,&nbsp;Fei Li,&nbsp;Juan Chen","doi":"10.1111/1365-2478.70012","DOIUrl":"https://doi.org/10.1111/1365-2478.70012","url":null,"abstract":"<p>The attenuation property of earth media can lead to amplitude loss and phase dispersion effects on multicomponent elastic data. Ignoring their impacts during imaging process will result in blurred and dislocated imaging profiles. To accurately characterize the attenuation effect in viscoelastic media, we first derive a new viscoelastic wave equation with decoupled fractional Laplacians. Numerical tests show that the proposed wave equation can accurately capture the propagation characteristics of seismic waves in viscoelastic media. Furthermore, our new wave equation can be modified to yield a decomposition equation, which enables the separated propagation of vector P- and S-wavefields. Building on the derived viscoelastic forward propagator, we develop a stable <i>Q</i>-compensated viscoelastic reverse-time migration approach. Usually, the inner product imaging condition is used to obtain imaging results. However, the result of inner product is affected by the angle between vectors, making the resulting images contaminated with the angle information. In this article, we introduce the magnitude- and sign-based imaging condition for PS imaging and conduct a cross-correlation imaging condition based on the scalar P-wavefield for PP imaging. In contrast to the inner product imaging condition, our imaging scheme is capable of overcoming the contamination by the angle information. In addition, high-frequency noise is amplified exponentially during the attenuation compensation process, affecting imaging precision. To address this problem, we derive the stabilized <i>Q</i>-compensation wave equations explicitly for vector- and scalar wavefields. Numerical examples demonstrate that the proposed <i>Q</i>-compensated viscoelastic reverse-time migration method can effectively correct the viscoelastic effects, yielding high-quality PP- and PS-imaging profiles.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1431-1455"},"PeriodicalIF":1.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950324","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":"Regularization with differential evolution-based common-offset common-reflection surface: A case study for field onshore seismic data","authors":"Tainá Souza,&nbsp;Tiago Barros,&nbsp;Renato Lopes","doi":"10.1111/1365-2478.70007","DOIUrl":"https://doi.org/10.1111/1365-2478.70007","url":null,"abstract":"<p>We introduce a novel approach for seismic pre-stack data regularization using the common-offset common-reflection-surface method with a global attribute search strategy, employing a bio-inspired differential evolution optimization algorithm. We compare the global common-offset common-reflection-surface approach with the conventional sequential attribute search, focusing on their performance in pre-stack data regularization. Tests on synthetic and onshore (field) seismic datasets demonstrate that the global search approach significantly improves performance, enhancing signal-to-noise ratio and coherently filling missing traces. We show that the global common-offset common-reflection-surface method effectively addresses spatial irregularities, reconstructing reflections without artefacts, filling data gaps and highlighting geological details even in complex areas. In contrast, the sequential common-offset common-reflection-surface method, while capable of reconstructing missing traces, shows lower interpolation quality and fails to adequately highlight complex geological features such as high-dip reflections.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1411-1430"},"PeriodicalIF":1.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950278","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":"Three-dimensional forward modelling and inversion of magnetic anomaly using finite-infinite element coupling method with Comsol: A case study of Pingchuan iron-ore deposit, Southwest China","authors":"Yinzhong Ma,&nbsp;Xiangyun Hu,&nbsp;Shuang Liu","doi":"10.1111/1365-2478.70010","DOIUrl":"https://doi.org/10.1111/1365-2478.70010","url":null,"abstract":"<p>We implemented the finite-infinite element coupling method in Comsol for three-dimensional magnetic forward modelling in geophysics exploration. The finite-infinite element coupling method optimizes boundary conditions by combining finite and infinite elements, and its boundary and mesh convergence were validated against analytical solutions. For non-ellipsoidal magnetic bodies without analytical solutions, we compared the forward magnetic anomaly solutions of a cube using the finite-infinite element coupling method and finite volume method with hexahedral meshes. The finite-infinite element coupling method demonstrated higher accuracy compared to the finite volume method under the presence of remanent magnetization, highlighting the impact of spatial discretization on solution quality. Simulation results from the rectangular prism and composite models showed that the finite-infinite element coupling method, through unstructured meshes, enables precise modelling of complex geometries and non-uniform magnetic field distributions. Using Comsol Multiphysics, we successfully applied the finite-infinite element coupling method for the three-dimensional inversion of ore body models and analysed data from the Pingchuan iron ore deposit in Southwest China. This study illustrates the applicability of the finite-infinite element coupling method in advancing magnetic modelling and the effectiveness of Comsol as a tool for characterizing complex geological structures.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1396-1410"},"PeriodicalIF":1.8,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950323","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":"Group velocity image of singularities for converted reflected and transmitted waves in orthorhombic anisotropic media","authors":"Alexey Stovas,&nbsp;Yuriy Roganov,&nbsp;Vyacheslav Roganov","doi":"10.1111/1365-2478.70005","DOIUrl":"https://doi.org/10.1111/1365-2478.70005","url":null,"abstract":"<p>We define double singularity points, lines and surfaces and their group velocity images for converted reflected and transmitted PS1 and PS2 waves in layered orthorhombic media. This is performed by considering the dominant term in Taylor series for Christoffel equation defined for converted waves. We show that the group velocity image for converted wave has the same functional form as the one for pure wave modes (ellipse in 3D). The position and area of the ellipse in the group velocity domain and offset domain are also analysed. We also expand this method for two-layer model with S1S2 wave singularity in both layers. It results in quartic (S1S1, S2S2, S1S2 and S2S1 waves) characteristic equation. In the group velocity domain, it gives two close curves: quasi-elliptical (for pure S1S1 and S2S2 waves) and very complex curve with deflection points (for converted S1S2 and S2S1 waves).</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1364-1378"},"PeriodicalIF":1.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950257","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":"Slope assisted Physics-informed neural networks for seismic signal separation with applications on ground roll removal and interpolation","authors":"Francesco Brandolin,&nbsp;Matteo Ravasi,&nbsp;Tariq Alkhalifah","doi":"10.1111/1365-2478.70004","DOIUrl":"https://doi.org/10.1111/1365-2478.70004","url":null,"abstract":"<p>The knowledge of the local slope field of prestack seismic data is essential in several seismic signal processing tasks. Building on our previous slope-assisted, physics-informed seismic interpolation framework, dubbed PINNslope, we introduce a series of enhancements that elevate the framework's versatility. This ultimately enables its application to different signal separation problems, with a specific focus on ground roll removal. To begin with, the local slope estimated using our physics-informed neural networks framework is compared against the analytical local slope and those obtained from several conventional slope estimation algorithms. This comparison showcases that our prediction better approximates the analytical one. Second, we use the derived relation between the analytical slope and the physics-informed neural networks estimated slope to constrain the slope estimation network in the ground roll removal problem, predicting only the clean reflections and avoiding the prediction of the ground roll. To address the large difference in the frequency content of the field data, we utilize a time derivative term in the loss function to emphasize the amplitude of the comparatively higher frequency reflection arrivals. Furthermore, we modify the framework loss function and architecture to demonstrate the possibility of predicting two separate components of the seismic data according to the estimate of two local slopes that can span opposite or different ranges of values between each other. The effectiveness of the double slope framework is demonstrated on a proof of concept of the deblending problem and for the interpolation of complex aliased data characterized by conflicting dips, two tasks that were not achievable using our single slope prediction network implementation.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1337-1363"},"PeriodicalIF":1.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950256","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":"Ore-controlling structures revealed by magnetic and resistivity anomalies in the Linares–La Carolina mining district (Spain)","authors":"J. Rey,&nbsp;R. Mendoza,&nbsp;J. Nuñez,&nbsp;F. J. Martínez-Moreno,&nbsp;M. C. Hidalgo","doi":"10.1111/1365-2478.70019","DOIUrl":"https://doi.org/10.1111/1365-2478.70019","url":null,"abstract":"<p>The effectiveness of magnetic and electromagnetic geophysical methods in delineating geological structures with mining implications was analysed in this study, specifically for structures that affect the possible extension of the lead-based metal phylonian deposits concealed by young sedimentary cover. This study focuses on the ancient mining district of Linares–La Carolina (south-eastern Spain), characterized by the presence of galena (PbS) deposits. In this sector, two of its main mining concessions (Arrayanes and San Miguel–El Mimbre) were selected, which lose continuity under the Plio–Quaternary basin cover of La Garza. The magnetic surveys reveal the presence of anomalies aligned in two directions, NW‒SE and SW‒NE. Calculated magnetic models indicate that these anomalies could be associated with faults. The continuity of the veins is disrupted or displaced when these anomalies are reached. Therefore, the study of these linear magnetic trends can help to locate these faults that control the continuity and displacement of the veins. Joint interpretation of new time-domain electromagnetic stations and electrical resistivity tomography profiles previously obtained reveal linear features that align with the faults interpreted from the magnetic results. This consistency between methods allowed us to corroborate the presence of these structures. The synergistic application of magnetic techniques alongside electrical or electromagnetic methods proves effective in identifying faults in the Arrayanes and San Miguel–El Mimbre mining concessions. The identified faults are significant for prospecting for mineral deposits as they are spatially associated with both vein disappearances and lateral changes in facies and thickness in the Quaternary fill of the La Garza sedimentary basin. This is evidence that the geophysically mapped faults have meaningful control on ore vein distribution.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 5","pages":"1379-1395"},"PeriodicalIF":1.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143950258","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":"Discretization of small-scale, stratigraphic heterogeneities and its impact on the seismic response: Lessons from the application of process-based modelling","authors":"Andrea Cuesta Cano,&nbsp;Azin Karimzadanzabi,&nbsp;Joep Elisabeth Anton Storms,&nbsp;Guillaume Rongier,&nbsp;Dirk Jacob Verschuur,&nbsp;Allard Willem Martinius","doi":"10.1111/1365-2478.70015","DOIUrl":"https://doi.org/10.1111/1365-2478.70015","url":null,"abstract":"&lt;p&gt;Reducing the uncertainty of reservoir characterization requires to better identify the small-scale structures of the subsurface from the available data. Studying the seismic response of meter-scale, stratigraphic heterogeneities typically relies on the generation of reservoir models based on outcrop examples and their forward seismic modelling. To bridge geological information and seismic modelling, these methods allocate values of acoustic properties, such as mass-density and P-wave velocity, according to discretized properties like layer-type lithology or facies units. This strategy matches the current workflow in seismic data inversion in industry, where modelling workflows are based on lithofacies distributions. However, from stratigraphic modelling, we know that meter-scale heterogeneities occur within certain facies and lithologies. Here, we evaluate the difference on the seismic response between allocating acoustic properties in a grain size–based, semi-continuous manner versus discretized manners based on lithology and facies classifications. To do so, we generate a reference geological simulation that we populate with acoustic properties, mass-density and P-wave velocity, using three different strategies: (1) based on grain size distribution; (2) based on facies distribution; and (3) based on lithology. The method we propose includes the generation of realistic geological simulations based on stratigraphic modelling and the transformation of its output into acoustic properties, honouring the intra-lithology and intra-facies, small-scale structures. We, then, generate seismic data by applying a forward seismic modelling workflow. The synthetic data show that the grain size–based simulation allows the identification of small-scale, stratigraphic heterogeneities, such as beds with strong density and velocity contrasts. These stratigraphic structures are smoothened or may completely disappear in the facies and lithology discretized simulations and, therefore, are not (well) represented in the synthetic seismic data. Recognizing meter-scale, stratigraphic heterogeneities is relevant for the characterization of the fluid flow in the reservoir. However, current discrete and lithology-based strategies in seismic inversion are not able to resolve such heterogeneities because real subsurface properties are not discrete properties but continuous, unless there are stratigraphic discontinuities such as erosional surfaces or faults. This research works towards a better understanding of the relationship between changes in these continuous properties and the observed seismic data by introducing greater complexity into the discretized geological simulations. Here, we use synthetic seismic images with the goal of eventually aiding in fine-tuning seismic inversion methodologies applied to real seismic data. One pathway is to foster the development of inversion approaches that can leverage stratigraphic modelling to get stronger geological priors and rep","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 4","pages":"1280-1300"},"PeriodicalIF":1.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1365-2478.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845835","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":"Three-dimensional gravity inversion based on the Hamiltonian Monte Carlo method","authors":"Ya Xu,&nbsp;Wei Chu,&nbsp;Song Huang,&nbsp;Rui Guo,&nbsp;Shupeng Lu,&nbsp;Fangzhou Nan","doi":"10.1111/1365-2478.70016","DOIUrl":"https://doi.org/10.1111/1365-2478.70016","url":null,"abstract":"<p>In geophysics, Bayesian inversion methods are of significant prominence. Here, we present a novel approach utilizing the Hamiltonian Monte Carlo (HMC) method in gravity inversion for elucidating three-dimensional (3D) density structures. HMC provides a multi-dimensional sampling method that demonstrates enhanced optimization efficiency, facilitating the attainment of distant proposals with elevated acceptance probabilities. Its applicability also extends to resolving linear inverse problems. Three synthetic models of cubic bodies, dipping dykes and a combined model were designed for tests. The testes underscore the promising potential of HMC in recovering subsurface density source bodies and giving the uncertainty of the inversion model. Furthermore, an inversion test conducted on the Vinton salt dome yields a reasonable 3D distribution of cap rock, consistent with prior studies in this area. The modelling and field experiments showed that the proposed HMC gravity inversion method had higher accuracy and application potential.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":"73 4","pages":"1301-1314"},"PeriodicalIF":1.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845836","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}