Browsing Earth Resources Laboratory by Title
Now showing items 8-27 of 456
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Acoustic Character Of Hydraulic Fractures In Granite
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1983)Hydraulic fractures in homogeneous granitic rocks were logged with conventional acoustic-transit-time, acoustic-waveform, and acoustic-televiewer logging systems. Fractured intervals ranged in depth from 45 to 570m. and ... -
Acoustic Logging Guided Waves In Transversely Isotropic Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)We have studied the velocity dispersion of guided waves in transversely isotropic formations. Theoretical velocity dispersion curves were calculated with elastic constants based on laboratory and field measurements and ... -
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 ... -
Acoustic Logging While Drilling (LWD): Experimental Studies with Anisotropic Models
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2002)A model LWD tool (0.16" ID, 0.4" OD) was built to investigate its operation in an anisotropic formation. The tool consists of a dipole source and six dipole receivers capable of operating at several hundred kHz. The ... -
Acoustic Wave Backscattering In A Random Inhomogeneous Ocean Sediment
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1995)The backscattering of sound by inhomogeneities of the ocean sediment may provide a remarkable effect on underwater acoustic wave propagation. It may also be used as a means of remotely estimating complicated sediment ... -
Acoustic Wave Propagation In A Fluid-Filled Borehole With A Horizontal Fracture
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1990)The propagation of guided waves in a fluid-filled borehole with an open horizontal fracture is investigated both theoretically and experimentally. The fracture is modeled as a fluid layer that separates the domain of ... -
Acoustic Wave Propagation In And Around A Fluid-Filled Borehole Of Irregular Cross-Section
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1994)Boreholes with 10% or more ellipticity are not uncommon. In this paper, we consider the coupling of an incident elastic wave into a borehole of irregular cross-section and investigate the cross-mode coupling phenomenon ... -
Acoustic Waveform Logging - Advances In Theory And Application
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1992-02)Full-waveform acoustic logging has made significant advances in both theory and application in recent years, and these advances have greatly increased the capability of log analysts to measure the physical properties of ... -
Advanced 3D Geophysical Imaging Technologies for Geothermal Resource Characterization
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012)We describe the ongoing development of joint geophysical imaging methodologies for geothermal site characterization and demonstrate their potential in two regions: Krafla volcano and associated geothermal fields in ... -
Aeolian And Fluvial Depositional Systems Discrimination In Wireline Logs: Unayzah Formation, Central Saudi Arabia
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2000)The objective of tills study is to discriminate between aeolian and fluvial deposits of the Permian Unayzah formation in Central Saudi Arabia by using wireline logs. The analysis is conducted on wire-line logs (field ... -
An Amplitude And Traveltime Calculation Using A Higher-Order Parabolic Equation
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1996)A higher-order parabolic equation is used to compute the traveltime (phase) and the amplitude in constant density acoustic media. This approach is in the frequency domain, thereby avoiding the high frequency approximation ... -
An Analysis Of Deconvolution: Modeling Reflectivity By Fractionally Integrated Noise
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1999)Reflection coefficients are observed in nature to have stochastic behavior that departs significantly from the white noise model. Conventional deconvolution methods, however, assume reflectivity to be a white noise ... -
Analysis of Full Waveform Acoustic Logging Data in "Soft" Formations
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)Direct recording of formation shear wave travel time is not possible in "soft" formations where the shear velocity is lower than the borehole fluid velocity. The borehole Stoneley wave is quite sensitive to changes in ... -
Analysis of location uncertainty for a microearthquake cluster: A case study
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2013)In many reservoirs, an increase in permeability and conductivity is achieved by hydraulic fracturing/stimulations which open cracks and fractures that then act as pathways for fluids to navigate in the subsurface. Mapping, ... -
Analysis Of Microseismic Location Accuracy For Hydraulic Fracturing At The DWTI Site, Jasper, Texas
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1995)This report presents the results of a feasibility study designed to assess whether microseismic location techniques can provide enough accuracy and precision to enable a high resolution study of the spatial distribution ... -
Analysis of Scattered Signal to Estimate Reservoir Fracture Parameters
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2007-05)We detect fracture corridors and determine their orientation and average spacing based on an analysis of seismic coda in the frequency-wave number (f-k ) domain. Fracture corridors have dimensions similar to seismic ... -
Anisotropic Perfectly Matched Layers for Elastic Waves in Cartesian and Curvilinear Coordinates
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2002)We develop new numerical anisotropic perfectly matched layer (PML) boundaries for elastic waves in Cartesian, cylindrical and spherical coordinate systems. The elasticity tensor of this absorbing boundary is chosen to be ... -
Annual Report 2012 Table of Contents
(Massachusetts Institute of Technology. Earth Resources Laboratory, 2012) -
Application of Full Waveform Acoustic Logging Data to the Estimation of Reservoir Permeability
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1984)Development of borehole geophysics has recently focused on reservoir characterization. Within this effort, extensive full waveform acoustic surveys have demonstrated a correlation between the occurance of open fractures ... -
Application Of Rayleigh's Principle To Guided Waves In A Borehole
(Massachusetts Institute of Technology. Earth Resources Laboratory, 1988)The Lagrangian for guided waves in a completely general borehole model is presented. Rayleigh's principle is used to derive the first order perturbations in wavenumber and frequency due to slight perturbations in the ...
