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Approximate inversion of the wave-equation Hessian via randomized matrix probing
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
We present a method for approximately inverting the Hessian of full waveform inversion as a dip-dependent and scale-dependent amplitude correction. The terms in the expansion of this correction are determined by least-squares ...
Nonlinear Frechet derivative and its De Wolf approximation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
We introduce and derive the nonlinear Frechet derivative for the acoustic wave equation. It turns out that the high order Frechet derivatives can be realized by consecutive applications of the scattering operator and a ...
A unified framework for relative source localization using correlograms
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
We study the problem of determining an unknown event location relative to previously located events using a single monitoring array in a monitoring well. We show that using the available information about the previously ...
Earth Resources Laboratory Annual Report 2013 Table of Contents
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
3D Weak-Dispersion Reverse-Time Migration with a StereoModeling Method
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
The finite difference method has been widely used in seismic modeling and reverse time migration. However, it generally has two issues: large computational cost and numerical dispersion. Recently, a nearly-analytic discrete ...
Seismic imaging of hydraullically-stimulated fractures: A numerical study of the effect of the source mechanism
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)
We present a numerical study of seismic imaging of hydraulically stimulated fractures using a single source from an adjacent fracturing-process. The source is either a point force generated from the perforation of the ...
Numerical modeling of elastic wave scattering by near-surface heterogeneities
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
A perturbation method for elastic waves and numerical forward modeling are used to calculate the effects of seismic wave scattering from arbitrary shape shallow subsurface heterogeneities. Wave propagation is simulated ...
The failure mode of correlation focusing for model velocity estimation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
We analyze the correlation focusing objective functional introduced by van Leeuwen and Mulder to avoid the cycle-skipping problem in full waveform inversion. While some encouraging numerical experiments were reported in ...
Using SVD for improved interferometric Green's function retrieval
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
Seismic interferometry (SI) is a technique used to estimate the Green’s function (GF) between two receiver locations, as if there were a source at one of the receiver locations. However, in many applications, the requirements ...
Real-time ensemble control with reduced-order modeling
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)
The control of spatially distributed systems is often complicated by significant uncertainty about system inputs, both time-varying exogenous inputs and time-invariant parameters. Spatial variations of uncertain parameters ...