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Related papers: Inversion of normal moveout for monoclinic media

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Reflection moveout of pure modes recorded on conventional-length spreads is described by a normal-moveout (NMO) velocity that depends on the orientation of the common-midpoint (CMP) line. Here, we introduce the concept of NMO-velocity…

Geophysics · Physics 2019-06-04 Vladimir Grechka , Ilya Tsvankin

Despite the complexity of wave propagation in anisotropic media, reflection moveout on conventional common-midpoint (CMP) spreads is usually well described by the normal-moveout (NMO) velocity defined in the zero-spread limit. In their…

Geophysics · Physics 2019-01-03 Vladimir Grechka , Ilya Tsvankin , Jack K. Cohen

Multi-azimuth walkaway vertical seismic profiling (VSP) is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy parameters. Normally, this the technique requires the assumption of lateral…

Geophysics · Physics 2023-11-17 Vladimir Grechka , Ilya Tsvankin , Pedro Contreras

We consider an anisotropic inhomogeneous model to simulate measured vertical-seismic-profile traveltimes. In this model, we assume that velocity increases linearly with depth and anisotropy is the result of elliptical velocity dependence.…

Geophysics · Physics 2020-12-08 Ayiaz Kaderali , Theodore Stanoev

Textures in images can often be well modeled using self-similar processes while they may at the same time display anisotropy. The present contribution thus aims at studying jointly selfsimilarity and anisotropy by focusing on a specific…

Data Analysis, Statistics and Probability · Physics 2015-06-16 S. G. Roux , M. Clausel , B. Vedel , S. Jaffard , P. Abry

Traditionally, the mass / velocity anisotropy degeneracy (MAD) inherent in the spherical, stationary, non-streaming Jeans equation has been handled by assuming a mass profile and fitting models to the observed kinematical data. Here, the…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-11 Gary A. Mamon , Gwenael Boué

Multiple vertical fracture sets, combined with horizontal fine layering produce an equivalent medium of orthorhombic or monoclinic symmetry. This is particularly important in fracture reservoir characterization. Fractured reservoirs are…

Geophysics · Physics 2019-11-12 Pedro Contreras , Luis Rincon , Jose Burgos

In Part I of this study, we obtained the ray (group) velocity gradients and Hessians with respect to the ray locations, directions and the anisotropic model parameters, at nodal points along ray trajectories, considering general anisotropic…

Geophysics · Physics 2021-12-01 Igor Ravve , Zvi Koren

In this paper, we study the Helmholtz transmission eigenvalue problem for inhomogeneous anisotropic media with the index of refraction $n(x)\equiv 1$ in two and three dimension. Starting with a nonlinear fourth order formulation established…

Numerical Analysis · Mathematics 2023-04-26 Qing Liu , Tiexiang Li , Shuo Zhang

Anisotropic fluid materials are of growing interest with the development of metamaterials and transformation acoustics. In the general three-dimensional case, such materials are characterized by a bulk modulus and a full symmetric matrix of…

Numerical mode matching (NMM) methods are widely used for analyzing wave propagation and scattering in structures that are piece-wise uniform along one spatial direction. For open structures that are unbounded in transverse directions…

Numerical Analysis · Mathematics 2018-04-24 Wangtao Lu , Ya Yan Lu , Dawei Song

The paper is concerned with the inverse scattering problem for Maxwell's equations in three dimensional anisotropic periodic media. We study a new imaging functional for fast and stable reconstruction of the shape of anisotropic periodic…

Numerical Analysis · Mathematics 2023-06-05 Dinh-Liem Nguyen , Trung Truong

Generalized ellipsometry, a non-destructive optical characterization technique, is employed to determine geometrical structure parameters and anisotropic dielectric properties of highly spatially coherent three-dimensionally nanostructured…

Optics · Physics 2015-06-16 Daniel Schmidt

Newtonian machine learning (NML) is a wave-equation inversion method that inverts single-dimensional latent space (LS) features of the seismic data for retrieving the subsurface background velocity model. The single-dimensional LS features…

Geophysics · Physics 2021-12-17 Yuqing Chen , Erdinc Saygin

In this article, we develop a 1-D traveltime tomography method to calculate the seismic P-wave velocity of a medium. We use the results of 1-D tomography to obtain linear inhomogeneity parameters in a specific layer. To get the…

Geophysics · Physics 2019-12-09 Md Abu Sayed

The conventional Perfectly Matched Layer (PML) is unstable for certain kinds of anisotropic media. This instability is intrinsic and independent of PML formulation or implementation. The Multi-axial PML (MPML) removes such instability using…

Geophysics · Physics 2016-12-22 Kai Gao , Lianjie Huang

Classically, anisotropic surface wave tomography is treated as an optimisation problem where it proceeds through a linearised two-step approach. It involves the construction of 2D group or phase velocity maps for each considered period,…

Geophysics · Physics 2020-12-08 John Keith Magali

Since the seminal paper by Mitra et al., diffusion MR has been widely used in order to estimate surface-to-volume ratios. In the present work we generalize Mitra's formula for arbitrary diffusion encoding waveforms, including recently…

Medical Physics · Physics 2019-11-14 Nicolas Moutal , Ivan I. Maximov , Denis S. Grebenkov

High-rank line-of-sight (LOS) MIMO systems have attracted considerable attention for millimeter wave and THz communications. The small wavelengths in these frequencies enable spatial multiplexing with massive data rates at long distances.…

Signal Processing · Electrical Eng. & Systems 2023-04-18 Yaqi Hu , Mingsheng Yin , Sundeep Rangan , Marco Mezzavilla

The vectorial evolution of polarized light interaction with a medium can reveal its microstructure and anisotropy beyond what can be obtained from scalar light interaction. Anisotropic properties (diattenuation, retardance, and…

Optics · Physics 2024-02-26 Zhineng Xie , Guowu Huang , Weihao Lin , Xin Jin , Yifan Ge , Yansen Hu , Xiafei Qian , Min Xu
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