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Stoneley Wave Propagation Across Borehole Permeability Heterogeneities
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1994)
An important application of borehole acoustic logging is the determination of formation
permeability using Stoneley waves. Heterogeneous permeable structures, such as fractures,
sand-shale sequences, etc., are commonly ...
Borehole Effects On Downhole Seismic Measurements
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1992)
An exact formulation for borehole coupling, which is valid for all frequencies and all
azimuthally symmetric and nonsymrnetric components, is given in this paper. The borehole
effects on downhole measurements are studied ...
Modelling Of Downhole Seismic Sources II: An Analysis Of The Heelan/Brekhovskikh Results And Comparison Of Point Source Radiation To Radiation From Boreholes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)
The work of Heelan (1952, 1953a,b) was one of the first studies of wave propagation
from a cylindrical boundary. Heelan attempted to model the radiation emanating from
a cylindrical shot hole filled with dynamite. To do ...
Fourth-Order Finite Difference Acoustic Logs In A Transversely Isotropic Formation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1993)
In this paper we present a finite difference scheme for seismic wave propagation in
a fluid-filled borehole in a transversely isotropic formation. The first-order hyperbolic
differential equations are approximated ...
Acoustic Logging In Randomly Stratified Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1993)
The propagation of borehole acoustic waves in the presence of various types of heterogeneous formations is investigated by modeling them as stratified media with varying velocity-depth distributions. Two types of formations ...
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 ...
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 ...
Inversion For Permeability From Stoneley Wave Velocity And Attenuation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)
The in situ permeability of a formation is obtained by the inversion of Stoneley wave
phase velocity and attenuation, which are evaluated by applying the Extended Prony's
method to the array sonic logging data. The Maximum ...
Experimental And Finite Difference Modelling Of Borehole Mach Waves
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1992)
A series of model experiments are done in the ultrasonic laboratory to study the radiation of downhole sources in a variety of formations. Three models are used in the
experiments. They are a lucite model, a lucite model ...
Cased Borehole Effect On Downhole Seismic Measurements
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1993)
Approximate and exact formulations are presented for the interaction of an incident
wave with a cased borehole. In the approximate method, the borehole coupling theory
is used to compute pressure in the fluid at a low ...