Results 251 to 260 of about 212,366 (287)
Some of the next articles are maybe not open access.
Optimal search strategies for nonlinear, multi-parameter geoacoustic inverse problems
The Journal of the Acoustical Society of America, 2003A mode travel time based technique for geoacoustic inversions has been developed using broadband explosive sources [Potty et al., J. Acoust. Soc. Am. 108, 973–986 (2000)]. In this inversion scheme we search for various parameters including water depth, sound speed in the water column represented by Empirical Orthogonal Function (EOFs), compressional ...
Gopu R. Potty +3 more
openaire +1 more source
Should We Move towards Multi-parameter Elastic Inversions?
Second EAGE/PESGB Workshop on Velocities, 2019Summary In its standard least-square formulation, full waveform inversion aims at matching both the phases and the amplitudes of the recorded events. The dynamics of the seismic waves, especially of the reflection waves are of elastic nature. Moreover, earth parameter variations inside the first Fresnel zone induce interference patterns that may also ...
openaire +1 more source
Multi-Parameter Pseudo Acoustic Full Waveform Inversion Method in Elastic World
82nd EAGE Annual Conference & Exhibition, 2021Summary In land seismic exploration, low-velocity zone causes the ray path of reflected wave propagating to the detector perpendicularly. Therefore, single-component data is regarded as P-wave data. In this paper, we first derive a new pseudo acoustic wave equation (PAE) in elastic world based on acoustic approximation.
Q. Li, G. Wu, P. Duan
openaire +1 more source
A Multi-parameter Full Waveform Inversion Strategy in Acoustic Media
Proceedings, 2014Full waveform inversion (FWI) is a challenging data-matching procedure that exploits the full information from the seismic data to obtain high-resolution models of the subsurface. To best fit the observed seismograms, the forward modeling should correctly account for the wave propagation phenomena present in the recorded data, especially for the wide ...
J.Z. Yang, Y.Z. Liu, L.G. Dong
openaire +1 more source
On unique solvability of multi-parameter waveguide inverse problems
2017 International Conference on Electromagnetics in Advanced Applications (ICEAA), 2017This paper provides an introduction to mathematical methods of analytical-numerical solution to multi-parameter waveguide inverse problems of reconstructing permittivity of layered dielectric inclusions from the values of the transmission and reflection coefficients.
openaire +1 more source
Migration and multi-parameter inversion in transversely isotropic elastic media
56th EAEG Meeting, 1994Transverse isotropy is a common form of anisotropy encountered in many physical applications. It can be intrinsic to a material or rock type, occurring due to thin layering or also by alignment of pores and fractures due to the stress conditions affecting a medium.
M. Ali, C. Tura
openaire +1 more source
Multi-Parameter Tomographic Inversion for Imaging 2D Electrical Resistivity Anisotropy
1st Conference on Geophysics for Geothermal-Energy Utilization and Renewable-Energy Storage, 2019Resistivity anisotropy is often encountered in practical applications due to different orientations of fractures, joints and crystalline in sedimentary rocks. It may not satisfy assumption of homogenous electrical current flows in all directions that is commonly used in electrical resistivity tomography (ERT).
B. Zhou, W. Moosoo
openaire +1 more source
Multi-parameter spectral inversion for GPR signals of subsurface layered media
2012 14th International Conference on Ground Penetrating Radar (GPR), 2012A frequency-domain spectral inversion algorithm is derived and verified in this paper, using which underground reflective surfaces' positions as well as each layer's thickness, dielectric permittivity and electric conductivity can be obtained simultaneously.
Huang Zhonglai, Zhang Jianzhong
openaire +1 more source
Acoustic and anisotropic multi-parameter seismic full waveform inversion case studies
SEG Technical Program Expanded Abstracts 2014, 2014Multi-parameter seismic full waveform inversion (FWI) is crucial to obtain reliable images of the subsurface. For cost efficiency, we often only carry out an anisotropic acoustic FWI while the data are elastic. In this way, we invert for two acoustic “kinematic” (velocity) parameters (for instance NMO velocity and ) and a “dynamic” parameter ...
René-Édouard Plessix +3 more
openaire +1 more source
A sparse reduced Hessian approximation for multi-parameter wavefield reconstruction inversion
SEG Technical Program Expanded Abstracts 2014, 2014SUMMARY Multi-Parameter full-waveform inversion is a challenging problem, because the unknown parameters appear in the same wave equation and the magnitude of the parameters can vary many orders of magnitude. This makes accurate estimation of multipleparameters very difficult.
Bas Peters, Felix J. Herrmann
openaire +1 more source