Publications
140 results found
Song C, Wang Y, 2023, Simulating seismic multifrequency wavefields with the Fourier feature physics-informed neural network, GEOPHYSICAL JOURNAL INTERNATIONAL, Vol: 232, Pages: 1503-1514, ISSN: 0956-540X
Zhao Z, Rao Y, Wang Y, 2023, Structure-adapted multi-channel matching pursuit for seismic trace decomposition, Pure and Applied Geophysics, ISSN: 0033-4553
Hao Y, Bell R, Rao Y, et al., 2023, Prediction of permian karst reservoirs in the yuanba gas field, northern sichuan basin, China, Marine and Petroleum Geology, Pages: 106160-106160, ISSN: 0264-8172
Cai S, Fang F, Wang Y, 2023, Nonstationary seismic-well tying with time-varying wavelets, Geophysics, Vol: 88, ISSN: 0016-8033
Seismic-well tying is an important technique for correlating well-logging curves in depth with seismic traces in time. An appropriate seismic-well tying technique must account for two types of nonstationarity: the nonstationary time errors in the synthetic seismic trace caused by the inaccurate time-depth relationship established based on sonic-logging velocity and the nonstationary seismic signals due to the time-varying wavelets during wave propagation. The nonstationary problems related to the time-depth relationship and the time-varying wavelets are interrelated in seismic-well tying procedure. We implemented a nonstationary seismic-well tying method by iteratively updating the time-depth relationship and estimating the time-varying wavelets. From the estimated time-varying wavelets, we also estimated a Q-value by assuming that the subsurface medium has a constant Q at depth and used the constant Q to constrain the variation of the seismic wavelet during propagation. Then, we used the improved time-depth relationship and time-varying wavelets with the Q constraint for further iterations. In the iterative procedure, we quantified the accuracy of the seismic-well tying result using the correlation coefficient between the synthetic and the true seismic trace in each iteration and evaluated the reliability using the normalized mean-square errors among the wavelets estimated in different iterations.
Xu Q, Wang Y, 2023, Determination of the viscoelastic parameters for the generalized viscoelastic wave equation, Geophysical Journal International, Vol: 233, Pages: 875-884, ISSN: 0956-540X
<jats:title>SUMMARY</jats:title> <jats:p>The viscoelasticity of subsurface media is succinctly represented in the generalized wave equation by a fractional time derivative. This generalized viscoelastic wave equation is characterized by the viscoelastic parameter and the viscoelastic velocity, but these parameters are not well formulated and therefore unfavourable for seismic implementation. Here, we prove that the generalized wave equation is causal and stable by deriving the rate-of-relaxation function. Causality and stability are two necessary conditions for the applicability of the wave equation in seismic simulations. On this basis, we determine the physical parameters for the application of the generalized wave equation. First, we formulate the relationship between the viscoelastic parameter and the constant Q model. The proposed frequency-independent relation agrees with the theoretical solution and fits the field data. Then, we formulate the viscoelastic velocity in terms of the reference velocity and the viscoelastic parameter. These two formulations adequately represent the viscoelastic effect in seismic wave propagation and lead to an improvement in the accuracy of the numerical simulation of the generalized viscoelastic wave equation.</jats:p>
Yao J, Warner M, Wang Y, 2023, Regularization of anisotropic full-waveform inversion with multiple parameters by adversarial neural networks, Geophysics, Vol: 88, Pages: R95-R103, ISSN: 0016-8033
The anisotropic full-waveform inversion (FWI) is a seismic inverse problem for multiple parameters, which aims to simultaneously reconstruct the vertical velocity and the anisotropic parameters of the earth's subsurface. This multiparameter inverse problem suffers from two issues. First, the objective function of the data fitting is less sensitive to the anisotropic parameters. Second, the crosstalk effect among the different parameters worsens the model update in the iterative inversion. We have developed a method that statistically regularizes the anisotropic FWI using Wasserstein adversarial networks, by penalizing the Wasserstein distance between the distribution of the current model parameters and that of the parameters at the borehole locations. The regularizer can mitigate the issues of anisotropic FWI with multiple parameters and therefore it also can be applied to other inverse problems with multiple parameters.
- Abstract
- Open Access Link
- Cite
- Citations: 1
Zhao Z, Rao Y, Wang Y, 2022, The W transform with a chirp-modulated window, GEOPHYSICS, Pages: 1-29, ISSN: 0016-8033
<jats:p> A high-resolution time?frequency spectrum is desirable for processing and interpreting seismic data. The standard W transform is a method that effectively preserves the resolution in the low-frequency region of the time?frequency spectrum of non-stationary seismic signals. To further increase the energy concentration of the time?frequency spectrum estimated with the standard W transform, we propose to combine the W transform with a chirp-modulated window. The chirp rate in the chirp-modulated window can control the rotation of the window in the time?frequency plane to achieve a better match with the time?frequency spectrum. Unlike the general linear chirplet transform, the chirp rate in the proposed algorithm can be directly determined with the estimated instantaneous frequency. It has been shown that the W transform with a chirp-modulated window maintains the resolution of the time?frequency spectrum and improves the energy concentration around the dominant frequency against noise. To speed up the computational process of the W transform with a chirp-modulated window, we formulate the transform as a matrix?vector multiplication, which can be accelerated by using GPU computations. The application of the proposed algorithm to synthetic and field data shows that the frequency anomalies can be easily identified with the proposed algorithm. </jats:p>
Wang G, Chen S, Wang Y, 2022, Direct inversion for the equivalent pore aspect ratio based on the theory of ellipsoid modelling, Geophysical Prospecting, ISSN: 0016-8025
Zhang H, Brito-Parada PR, Neethling SJ, et al., 2022, Yield stress of foam flow in porous media: The effect of bubble trapping, COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, Vol: 655, ISSN: 0927-7757
Wang Y, 2022, Time–frequency Analysis of Seismic Signals, Publisher: Wiley, ISBN: 9781119892342
Time–frequency analysis of seismic signals aims to reveal the local properties of nonstationary signals. The local properties such as time-period, frequency, and spectral content are varying with time, and the time of a seismic signal is a proxy of geologic depth. Therefore, the time–frequency spectrum is composed of the frequency spectra that are generated by using the classic Fourier transform at different time positions. Different time–frequency analysis methods are distinguished in the construction of the local kernel prior to using the Fourier transform. Based on the difference in constructing the Fourier transform kernel, this book divides time–frequency analysis methods into two groups, the Gabor transform-type methods and the energy density distribution methods. This book provides a practical guide to geophysicists who attempt to generate geophysically meaningful time–frequency spectra, who attempt to process seismic data with time-dependent operations for the fidelity of nonstationary ...
Wang Y, 2022, Time-frequency domain local spectral analysis of seismic signals with multiple windows, PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, Vol: 478, ISSN: 1364-5021
Yu Y, Cilliers J, Hadler K, et al., 2022, A review of particle transport and separation by electrostatic traveling wave methods, Journal of Electrostatics, Vol: 119, Pages: 1-16, ISSN: 0304-3886
The controlled movement of dry particles using non-mechanical means is desirable in a number of different applications, including solar panel dust mitigation, toner particle motion and in the handling and beneficiation of regolith for In-Situ Resource Utilization (ISRU). The electric curtain, the electrostatic traveling wave (ETW) and the electro-dynamic screen (EDS) are examples of techniques that can transport and separate particles with no moving parts nor fluid medium. This review paper brings together the research carried out on these techniques.We provide a comprehensive review on the particle movement mechanisms and the development and application of ETW methods, featuring a diverse range of hardware and circuitry, particulate material and process objectives. We focus on the evaluation of experimental development in the area of dust mitigation, particle transport and ISRU processes. We also detail the current knowledge about theory and modelling methods. Moreover, we provide a guide for possible improvement of the effectiveness of ETW devices, by outlining the limitations in application, theoretical understanding and potential research aspects.
Guo X, Shi Y, Wang W, et al., 2022, Suppressing migration noise in reverse time migration of vertical seismic profiles by multiple stacking estimation, GEOPHYSICS, Vol: 87, Pages: S223-S235, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 1
XU QIANG, WANG YANGHUA, 2022, Spatial Filter for the Pseudo-spectral Implementation of Fractional Derivative Wave Equation, PURE AND APPLIED GEOPHYSICS, Vol: 179, Pages: 2831-2840, ISSN: 0033-4553
Yao J, Warner M, Wang Y, 2022, Generating surface-offset common-image gathers with backward wavefield synthesis, GEOPHYSICS, Vol: 87, Pages: S129-S135, ISSN: 0016-8033
Song C, Wang Y, 2022, High-frequency wavefield extrapolation using the Fourier neural operator, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 19, Pages: 269-282, ISSN: 1742-2132
Yao J, Wang Y, 2022, Building a full-waveform inversion starting model from wells with dynamic time warping and convolutional neural networks, GEOPHYSICS, Vol: 87, Pages: R223-R230, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 2
Ni J, Gu H, Wang Y, 2022, Seismic wave equation formulated by generalized viscoelasticity in fluid-saturated porous media, GEOPHYSICS, Vol: 87, Pages: T111-T121, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 2
OMalley CPB, Roberts GG, Mannion PD, et al., 2022, Coherence of Terrestrial Vertebrate Species Richness with External Drivers Across Scales and Taxonomic Groups, Publisher: Cold Spring Harbor Laboratory
<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>Understanding connections between environment and biodiversity is crucial for conservation, identifying causes of ecosystem stress, and predicting population responses to changing environments. Explaining biodiversity requires an understanding of how species richness and environment co-vary across scales. Here, we identify scales and locations at which biodiversity is generated and correlates with environment.</jats:p></jats:sec><jats:sec><jats:title>Location</jats:title><jats:p>Full latitudinal range per continent.</jats:p></jats:sec><jats:sec><jats:title>Time period</jats:title><jats:p>Present-day.</jats:p></jats:sec><jats:sec><jats:title>Major taxa studied</jats:title><jats:p>Terrestrial vertebrates: all mammals, carnivorans, bats, songbirds, humming-birds, amphibians.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We describe the use of wavelet power spectra, cross-power and coherence for identifying scale-dependent trends across Earth’s surface. Spectra reveal scale- and location-dependent coherence between species richness and topography (<jats:italic>E</jats:italic>), mean annual precipitation (<jats:italic>Pn</jats:italic>), temperature (<jats:italic>Tm</jats:italic>) and annual temperature range (∆<jats:italic>T</jats:italic>).</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p><jats:italic>></jats:italic>97% of species richness of taxa studied is generated at large scales, i.e. wavelengths 10<jats:sup>3</jats:sup>km, with 30–69% generated at scales 10<jats:sup>4</jats:sup>km. At these scales, richness tends to be highly cohere
Alsalmi H, Wang Y, 2021, Mask filtering to the Wigner-Ville distribution, GEOPHYSICS, Vol: 86, Pages: V489-V496, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 1
Jamali J, Javaherian A, Wang Y, et al., 2021, The behavior of elastic moduli with fluid content in the VTI media, JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING, Vol: 208, ISSN: 0920-4105
Wu D, Wang Y, Cao J, et al., 2021, Least-squares reverse-time migration with sparsity constraints, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 18, Pages: 304-316, ISSN: 1742-2132
- Author Web Link
- Open Access Link
- Cite
- Citations: 9
Izadian S, Aghazade K, Amini N, et al., 2021, Semi-exact local absorbing boundary condition for seismic wave simulation, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 18, Pages: 62-73, ISSN: 1742-2132
Wang Y, 2021, The W transform, GEOPHYSICS, Vol: 86, Pages: V31-V39, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 14
Rosa DR, Santos JMC, Souza RM, et al., 2020, Comparing different approaches of time-lapse seismic inversion, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 17, Pages: 929-939, ISSN: 1742-2132
- Author Web Link
- Open Access Link
- Cite
- Citations: 2
Duarte EF, da Costa CAN, de Araujo JM, et al., 2020, Seismic shot-encoding schemes for waveform inversion, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 17, Pages: 906-913, ISSN: 1742-2132
- Author Web Link
- Open Access Link
- Cite
- Citations: 1
Wang Y, Liu X, Gao F, et al., 2020, Robust vector median filtering with a structure-adaptive implementation, GEOPHYSICS, Vol: 85, Pages: V407-V414, ISSN: 0016-8033
- Author Web Link
- Cite
- Citations: 11
Li H, Gao R, Wang Y, 2020, Predicting the thickness of sand strata in a sand-shale interbed reservoir based on seismic facies analysis, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 17, Pages: 592-601, ISSN: 1742-2132
- Author Web Link
- Open Access Link
- Cite
- Citations: 2
Wang R, Wang Y, Rao Y, 2020, Seismic reflectivity inversion using an L1-norm basis-pursuit method and GPU parallelisation, JOURNAL OF GEOPHYSICS AND ENGINEERING, Vol: 17, Pages: 776-782, ISSN: 1742-2132
Wang Y, Rao Y, 2020, Seismic, Waveform Modeling and Tomography, Encyclopedia of Solid Earth Geophysics, 2nd edition, Editors: Gupta, Publisher: Springer, Cham, ISBN: 978-3-030-10475-7
Tomography. A seismic inversion method to produce slicing image of the internal structures of an object, by recording seismic wavefield propagating through and scattered-refracted-reflected back from the object and observing the difference in the effects on the wave energy impinging on those structures.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.