Browsing Earth Resources Laboratory by Title
Now showing items 87-106 of 456
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Dispersion Analysis Of Split Flexural Waves
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1997)In this paper we first present a technique for measuring dispersion curves from array data, that is both simple and efficient. We demonstrate its performance on both synthetic and field data. We then use the technique to ... -
Dispersion Curves and Synthetic Microseismograms in Unbonded Cased Boreholes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)The dispersion relations and impulse response. are calculated for a geometry consisting of an arbitrary number of coaxial annuli surrounding a central cylinder. The annuli may be either solid or fluid. The formulation ... -
Dispersive Wave Analysis – Method and Applications
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2005)A technique for estimating the dispersion characteristics of propagating waves as measured by an array is detailed. The technique consists of bandpass filtering the data through a filterbank and then processing the filtered ... -
Double-beam stacking to infer seismic properties of fractured reservoirs
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2011)We develop a theory for using 3D beam interference to infer scattering properties of a fractured reservoir using reflected seismic P data. For the sake of simplicity, we use Gaussian beams. The scattering properties are ... -
Double-Difference Waveform Inversion of 4D Ocean Bottom Cable Data: Application to Valhall, North Sea
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)Changes in reservoir properties resulting from extracting hydrocarbons and injecting fluid are critical to optimize production. These properties can be characterized using waveform inversions of time-lapse seismic data. ... -
Downhole microseismic monitoring of hydraulic fracturing: a full-waveform approach for complete moment tensor inversion and stress estimation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2010)Downhole microseismics has gained in popularity in recent years as a way to characterize hydraulic fracturing sources and to estimate in-situ stress state. Conventional approaches only utilize part of the information ... -
Dynamic And Static Green's Functions In Transversely Isotropic Elastic Media
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1993)Concise and numerically feasible dynamic and static Green's functions are obtained in dyadic form by solving the wave equation and the equilibrium equation with general source distribution in transversely isotropic (TI) ... -
Dynamic Fluid Flow In Heterogeneous Porous Media And Through A Single Fracture With Rough Surfaces
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1992)This study investigates the frequency-dependence of fluid flow in heterogeneous porous media using the theory of dynamic permeability and a finite-difference method. Given a permeability distribution, the dynamic ... -
A Dynamic Model For Fluid Flow In A Borehole Fracture
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)The attenuation of Stoneley waves by a borehole fracture are closely related to fluid flow in the fracture. We consider the dynamic response of a viscous fluid in a horizontal fracture to the oscillating pressure excitation ... -
Dynamic Permeability And Borehole Stoneley Waves: A Simplified Biot-Rosenbaum Model
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)Stoneley waves in permeable boreholes are diagnostic of formation permeability because their propagation is affected by the dynamic fluid flow at the borehole wall. We characterize this flow using the concept of dynamic ... -
Dynamic Streaming Currents From Seismic Point Sources In Homogeneous Poroelastic Media
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1996)In a porous medium saturated with a fluid electrolyte, mechanical and electromagnetic disturbances are coupled. The coupling is electrokinetic in nature since it is due to an excess of electrolyte ions that exist in an ... -
Earth Resources Laboratory Annual Report 2013 Table of Contents
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013) -
Effect of borehole stress concentration on compressional wave velocity measurements
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)Formation elastic properties near a borehole may be altered from their original state due to the stress concentration around the borehole. This could lead to a biased estimation of formation elastic properties measured ... -
The Effect Of Image Resolution On Fluid Flow Simulations In Porous Media
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2000)Realistic simulations of flow in porous media are dependent upon having a three-dimensional, high resolution image of pore structure which is difficult to obtain. So, we ask the question, "How fine a resolution is necessary ... -
The effect of stresses on the sound velocity in rocks: Theory of Acoustoelasticity and Experimental Measurements
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2001)The theory of acoustoelasticity provides direct link between the change of elastic wave velocities and residual stresses in solids. The general theory of acoustoelasticity is reviewed. A number of experimental measurements ... -
Effective Conductivity Modeling of a Fluid Saturated Porous Rock
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2007-05-27)The microstructure of a porous medium and physical characteristics of the solid and the fluids that occupy the pore space determine the macroscopic transport properties of the medium. The computation of macroscopic ... -
Effects Of A Borehole Environment And Residual Hydrocarbon On Stoneley Wave Amplitude And Reflectivity
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1996)In recent years, borehole Stoneley wave amplitude and reflectivity have been used for estimating formation permeability based on the strong correlation between Stoneley wave attenuation, reflectivity and formation fluid ... -
Effects Of A Logging Tool On The Stoneley Wave Propagation In Elastic And Porous Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1991)A detailed study is carried out to investigate the effects of an acoustic logging tool on the propagation characteristics of Stoneley waves in both elastic and porous formations. In an elastic formation, the presence of ... -
Effects of an Off-centered Tool on Multi-component Monopole and Dipole Logging
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2003)Recent logging tools have monopole and dipole sources in one system, and the monopole and dipole components are acquired by adding or subtracting responses at four monopole (pressure) receiver arrays at right angles. We ... -
Effects Of Anisotropy Upon The Normal Modes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)The effects of anisotropy upon elastic wave propagation along a fluid-filled cylindrical borehole are determined. The wave equation is solved in the frequency-wavenumber domain with a variational method, and the solution ...
