Browsing Earth Resources Laboratory by Title
Now showing items 442456 of 456

Variable Grid FiniteDifference Modeling Including Surface Topography
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1999)We have developed a twodimensional viscoelastic finitedifference modeling method for highly complex topography. Realistic modeling of seismic wave propagation in the near surface is complicated by many factors, such ... 
Velocity Analysis Of MultiReceiver Full Waveform Acoustic Logging Data In Open And Cased Holes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1986)Average semblance and maximumlikelihood spectral analysis are applied to synthetic full waveform acoustic logging data to determine formation velocities. Of particular interest is the ability of these methods to resolve ... 
Velocity Analysis of MultiReceiver Full Waveform Acoustic Logging Data In Open and Cased Holes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)Average semblance and maximumlikelihood spectral analyses are applied to synthetic and field full waveform acoustic logging data to determine formation velocities. Of particular interest is the ability of these methods ... 
Velocity Anisotropy Of Two Deep Crystalline Samples
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1989)Using ultrasonic velocity measurements taken over a multiplicity of directions we show that samples exhibit weak to moderate anisotropy of seismic velocities. We further define the anisotropic geometry with high resolution ... 
Viscous Attenuation Of Acoustic Waves In Suspensions
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)A model for attenuation of acoustic waves in suspensions is proposed which includes an energy loss due to viscous fluid flow around spherical particles. The expression for the complex wavenumber is developed by considering ... 
Viscous Fluid Effects on Guided Wave Propagation in a Borehole
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)In order to investigate the effect of borehole fluid viscosity on the attenuation and dispersion of the guided waves present in full waveform acoustic logs, the problem of wave propagation in a borehole containing a ... 
Viscous Fluid Effects on Guided Wave Propagation in a Borehole
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)In order to investigate the effect of borehole fluid viscosity on the attenuation and dispersion of the guided waves present in full waveform acoustic logs, the problem of wave propagation in a borehole containing a ... 
Visibility Analysis using Reverse Time Wave Sensitivity for TimeLapse TargetOriented Imaging
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2011)Identifying the relationship between surface seismic data and a particular region in the earth, referred to as visibility analysis, is important because it facilitates the optimization of the quality and speed of the imaging ... 
Wave Propagation In A FluidFilled FractureAn Experimental Study
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1989)A laboratory experimental study has been carried out to investigate the mode trapping characteristics of a fluidfilled fracture between two elastic solids. Using a small circular cylindrical receiver of 2.7 mm diameter, ... 
WaveEquation Reflection Tomography: Annihilators and Sensitivity Kernals
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2007)In seismic tomography, the finite frequency content of broadband data leads to interference effects in the process of medium reconstruction, which are ignored in traditional ray theoretical implementations. Various ways ... 
Wavelet Domain Geophysical Inversion
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2002)We present a nonlinear method for solving linear inverse problems by thresholding coefficients in the wavelet domain1. Our method is based on the waveletvaguelette decomposition of Donoho (1992). Numerical results for ... 
Wavelet domain linear inversion with application to well logging
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2001)Solving linear inversion problems in geophysics is a major challenge when dealing with nonstationary data. Certain nonstationary data sets can be shown to lie in Besov function spaces and are characterized by their ... 
WelltoWell Log Correlation Using KnowledgeBased Systems and Dynamic Depth Warping
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)We present a novel system for welltowell log correlation using knowledgebased systems and dynamic depth warping techniques. This approach overcomes a major drawback inherent in previous methods, namely the difficulty ... 
Untitled
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1996)This is the second year we have combined the work of the Logging and Reservoir Delineation groups at the Earth Resources Laboratory. In the first part of this report, we present work related to logging and petrophysics, ... 
Untitled
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1994)This paper describes a propagator matrix formulation for the problem of the Stoneley wave propagation in an irregular borehole. This is based on a simple onedimensional theory that is possible for the low frequency ...