Effects of single fractures on seismic wave propagation

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:7041898

Myer, L R ^[1]; Pyrak-Nolte, L J ^[2]; Cook, N G.W. ^[3]

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1. Lawrence Berkeley Lab., CA (USA)
2. Purdue Univ., Lafayette, IN (USA). Dept. of Earth and Atmospheric Sciences
3. Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Materials Science and Mineral Engineering

Detection and characterization of fractures, joints and faults remains an important problem in mining and geotechnical engineering, as well as in petroleum reservoir engineering. A theoretical model has been developed which predicts the amplitude and group time delay of the transmitted, reflected, and converted waves resulting from a plane wave incident upon a single fracture. It is assumed that seismic stresses are continuous across the interface. Seismic particle displacements, however, are assumed to be discontinuous. For completely dry conditions, the magnitude of the displacement discontinuity is given by the ratio of the seismic stress to the stiffness, {kappa}, of the fracture. If a fluid is present in the fracture, we postulate that, in addition to the displacement discontinuity, a velocity discontinuity exists which is equal to the ratio of the seismic stress to specific viscosity, {eta}. The wave equation has been solved for two sets of boundary conditions, with each set incorporating both specific stiffness and specific viscosity. These boundary conditions have been designated as Kelvin and Maxwell models. 12 refs., 5 figs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• Sponsoring Organization: DOE/ER; DOE/RW
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 7041898
• Report Number(s): LBL-28442; CONF-900640--4; ON: DE90009191
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580000 -- Geosciences
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
FLUID FLOW
GEOLOGIC DEPOSITS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
MATHEMATICAL MODELS
MINERAL RESOURCES
OIL FIELDS
PETROLEUM DEPOSITS
RESOURCES
ROCKS
SEISMIC EFFECTS
SEISMIC WAVES
STRESSES
VISCOSITY
WAVE PROPAGATION