Browsing Earth Resources Laboratory by Title
Now showing items 167-186 of 456
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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 ... -
A fast butterfly algorithm for the hyperbolic Radon transform
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)We introduce a fast butterfly algorithm for the hyperbolic Radon transform commonly used in seismic data processing. For two-dimensional data, the algorithm runs in complexity O(N[superscript 2] logN), where N is representative ... -
Fast Inversion Of Formation Permeability From Stoneley Wave Logs Using A Simplified Blot-Rosenbaum Model
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1994)This paper describes a fast algorithm for estimating formation permeability from Stoneley wave logs. The procedure uses a simplified Biot-Rosenbaum model formulation. The input to the inversion is the Stoneley wave ... -
A field expansions method for scattering by periodic multilayered media
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)The interaction of acoustic and electromagnetic waves with periodic structures plays an important role in a wide range of problems of scientific and technological interest. This contribution focuses upon the robust and ... -
Field Test of a Low-Frequency Sparker Source for Acoustic Waveform Logging
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)Low-frequency acoustic-energy sources for waveform logging have important applications in: 1) Verifying theoretical calculations; 2) generating tube waves in large-diameter boreholes; and 3) providing larger sample volumes ... -
Finite Difference Elastic Wave Modeling Including Surface Topography
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2011)Surface topography and the weathered zone (i.e., heterogeneity near the earth’s surface) have great effects on elastic wave propagation. Both surface waves and body waves are contaminated by scattering and conversion by ... -
A Finite Difference Formulation of Biot's Equations for Vertically Heterogeneous Full Waveform Acoustic Logging Problems
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)In this paper we present a finite difference formulation for Biot's equations for wave propagation in saturated porous media which vary in range and depth. One objective of well logging petroleum exploration holes is to ... -
Finite Difference Modeling of Attenuation and Anisotropy
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2003)A nite difference scheme which includes the effects of attenuation and anisotropy is tested for seismic reflection and borehole acoustic models. The validity of the scheme is established using a 3D homogenous isotropic ... -
Finite Difference Modeling of Seismic Responses to Intersecting Fracture Sets
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2006)Fractured reservoir characterization is becoming increasingly important for the petroleum industry. Currentmethods for this task are developed based on effectivemedia theory, which assumes the cracks or fractures in a ... -
Finite Difference Modelling Of Acoustic Logs In Vertically Heterogeneous Biot Solids
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)This paper discusses the results of tests carried out on a finite difference formulation of Biot's equations for wave propagation in saturated porous media which vary in range and depth (Stephen, 1987). A technique for ... -
Finite Difference Synthetic Acoustic Logs
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)Synthetic seismograms of elastic wave propagation in a fluid-filled borehole were generated using both the finite difference technique and the discrete wavenumber summation technique. The latter is known to be accurate for ... -
Finite-Difference Simulations of Time Reversed Acoustics in a Layered Earth Model
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2007)Traditionally an earthquake is located by using the arrival times of P and S phases. This uses only a limited portion of the information on a seismogram. A large part of the information carried by the waveform is not used. ... -
Flexural Waves In An Anisotropic Hard Formation Borehole Model
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1996)To investigate the propagation of flexural waves in a borehole surrounded by an azimuthally anisotropic hard formation, we made an ultrasonic borehole model of Delabole slate with very strong anisotropy. The axial and ... -
Fluid Flow In Porous Media: NMR Imaging And Numerical Simulation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1999)We use nuclear magnetic resonance (NMR) imaging to obtain a three-dimensional image of the pore structure in a limestone core, 4.5 mm in diameter and 10 mm in length, with a resolution of 40 μm. This image is converted ... -
Fluid Flow Modeling in Fractures
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2004)In this paper we study fluid flow in fractures using numerical simulation and address the challenging issue of hydraulic property characterization in fractures. The methodology is based on Computational Fluid Dynamics, ... -
Fluid Flow Property Estimation from Seismic Scattering Data
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)We present a methodology for relating seismic scattering signals from fractures to the fluid permeability field of the fracture network. The workflow is used to interpret seismic scattering signals for the reservoir ... -
Fluid Flow Simulation in Fractured Reservoirs
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2002)The purpose of this study is to analyze fluid flow in fractured reservoirs. In most petroleum reservoirs, particularly carbonate reservoirs and some tight sands, natural fractures play a critical role in controlling fluid ... -
Focal Mechanism Determination of Induced Microearthquakes in an Oil Field Using Full Waveforms from Shallow and Deep Seismic Networks
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2011-05-09)A new, high frequency, full waveform matching method is used to study the focal mechanisms of small, local earthquakes induced in an oil field, which are monitored by a sparse near-surface network and a deep borehole ... -
Focal Mechanism Determination Using High Frequency Waveform Matching and Its Application to Small Magnitude Induced Earthquakes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)We present a new method using high frequency full waveform information to determine the focal mechanisms of small, local earthquakes monitored by a sparse surface network. During the waveform inversion, we maximize both ... -
Focal Mechanism Determination using High Frequency, Full Waveform Information
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2009)In this research, we use high frequency waveform information to determine the focal mechanisms of small local earthquakes at an oil reservoir. During the waveform inversion, we maximize both the phase and amplitude matching ...
