Search
Now showing items 1-10 of 12
Estimating Phase Velocity and Attenuation of Guided Waves in Acoustic Logging Data
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
Phase velocity and attenuation of guided waves have been estimated from multireceiver,
full waveform, acoustic logging data using the extended Prony's method. Since a formation
affects velocity and attenuation, estimating ...
Full Waveform Inversion of P Waves for V[subscript s] and Q[subscript p]
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
We present an indirect method of determining shear wave velocities from full waveform
acoustic logs based on the inversion of the spectral ratio of the P-wave trains at two
source-receiver separations. This method ...
Experimental Verification of Acoustic Waveform and VSP Seismic Tube Wave Measurements of Fracture Permeability
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
A variety of established and experimental geophysical techniques was used to measure
the vertical distribution of fracture permeability in a 229-meter deep borehole penetrating schist and quartz monzonite near Mirror Lake, ...
Shear Wave Logging In Semi-Infinite Saturated Porous Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
Recent theoretical and experimental studies have demonstrated the interest of using
non-axisymmetric sources, such as dipole and quadrupole, to record shear wave events
in any kind of formation (fast or slow). Non-axisymmetric ...
Inversion of Borehole Guided Wave Amplitudes for Formation Shear Wave Attenuation Values
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
A linear least squares inversion, based on analytic partition coefficient expressions, is
developed to estimate the fluid and formation shear wave Q values from spectral ratio
measurements-of the guided wave arrivals of ...
Logging in Multilayered Saturated Porous Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
We present a general formulation based on the Thomson-Haskell method which allows
the study of complex models. The surrounding formation may be composed of several
coaxial porous shells or of a combination of both porous ...
Determining Shear Wave Velocities in Soft Marine Sediments
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
The inversion technique presented in this volume (Cheng, 1987) that simultaneously
inverts full waveform acoustic logs for shear wave velocity (V[subscript 3]) and compressional wave attenuation (Q[subscript p]) was applied ...
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 ...
Report Summary
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
This report contains the results ot work completed during the fifth year of the Full
Waveform Acoustic Logging Consortium in the Earth Resources Laboratory at M.l.T.
During this past year, the emphasis in our research ...
Velocity Analysis of Multi-Receiver Full Waveform Acoustic Logging Data In Open and Cased Holes
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1987)
Average semblance and maximum-likelihood 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 ...