Plane-layered models for the analysis of wave propagation in reservoir environments

Journal Article · Mon Jan 01 04:00:00 EST 1996 · Geophysical Prospecting

DOI:https://doi.org/10.1111/j.1365-2478.1996.tb00136.x· OSTI ID:207848

Carcione, J M ^[1]

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1. Osservatorio Geofisico Sperimentale, Trieste (Italy)

The long-wavelength propagation and attenuation characteristics of three geological structures that frequently occur in reservoir environments are investigated using a theoretical model that consists of a stack of fine and viscoelastic plane layers, with the layers being either solid or fluid. Backus theory properly describes fine layering and a set of fluid-filled microfractures, under the assumption that interfaces between different materials are bonded. The effects of saturation on wave attenuation are modeled by the relative values of the bulk and shear quality factors. The anisotropic quality factor in a fine-layered system shows a variety of behaviors depending on the saturation and velocities of the single constituents. The wave is less attenuated along the layering direction when the quality factors are proportional to velocity, and vice versa when inversely proportional to velocity. Fractured rocks have very anisotropic wavefronts and quality factors, in particular for the shear modes which are strongly dependent on the characteristics of the fluid filling the microfractures. When the size of the boundary layer is much smaller than the thickness of the fluid layer, the stack of solid-fluid layers becomes a layered porous media of the Biot type. This behavior is caused by the slip-wall condition at the interface between the solid and the fluid. As in Biot theory, there are two compressional waves, but here the medium is anisotropic and the slow wave does not propagate perpendicular to the layers. Moreover, this wave shows pronounced cusps along the layering direction, like shear waves in a very anisotropic single-phase medium.

• Sponsoring Organization: USDOE
• OSTI ID: 207848
• Journal Information: Geophysical Prospecting, Journal Name: Geophysical Prospecting Journal Issue: 1 Vol. 44; ISSN GPPRAR; ISSN 0016-8025
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
58 GEOSCIENCES
ATTENUATION
DATA ANALYSIS
GEOLOGIC STRUCTURES
MATHEMATICAL MODELS
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESPONSE FUNCTIONS
SEISMIC SURVEYS
SEISMIC WAVES
WAVE PROPAGATION