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Detection of Open Fractures with Vertical Seismic Profiling
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984-01-01)
In Vertical Seismic Profiling surveys tube waves are generated by compressional waves impinging on subsurface fractures or permeable zones. The problem of generation of these waves by a non-normal incident P wave for an ...
Detection Of Subsurface Fractures And Permeable Zones By The Analysis Of Tube Waves
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)
In Vertical Seismic Profiling tube waves are generated by compressional
waves impinging on subsurface fractures or permeable zones. The amplitude of
tube waves is dependent upon the formation permeability, the length of ...
Determination of Shear Wave Velocity and Attenuation From Waveforms in Low Velocity Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)
In boreholes where formation shear velocity is lower than borehole fluid velocity neither refracted shear waves nor pseudo-Rayleigh waves can propagate. When frequency response of the sonde does not extend to low frequencies ...
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 ...
Inversion of Travel Time for Velocity Using Multi-Spacing Sonic Tools
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1985)
Spatial resolution of sonic logs is greatly affected by the minimum spacing
between receivers. Improvements can be made, however, when the spatial sampling
of the formation is less than the minimum spacing. This paper ...
Transverserly Isotropic Saturated Porous Formations: II. Wave Propagation And Application To Multipole Logging
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)
The wavefields generated by monopole and dipole sources in a fluid filled borehole embedded in multilayered transversely isotropic saturated porous formations are studied.
The layers are modeled following Biot theory ...
P And S Wave Velocity Determination
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)
There are three general methods that can be used to determine formation velocities from full waveform logs. The first approach is to make use of the data from the entire waveform. This type of velocity analysis is performed ...
Frequency and Scale Effects in the Optimization of Acoustic Waveform Logs
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)
Previously formulated scaling laws relating acoustic waveforms in
boreholes to frequency, tool size and borehole diameter were investigated by
repeated logging of the same test interval with different frequencies, and ...
Nullerical Studies of Body Wave Amplitudes in Full Waveform Acoustic Logs
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)
The amplitudes of P and S head waves in a full waveform acoustic log microseismogram are studied numerically as a function of borehole and formation parameters. The technique used is contour integration around the respective ...
The Effects Of High Pressure-High Temperature On Some Physical Properties Of Ocean Sediments
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)
A series of laboratory experiments was conducted with four ocean sediments, two biogenic oozes and two clays. Permeability and thermal conductivity were directly measured as a function of porosity and the testing program ...