Journal ArticleDOI
Effect of High-Pressure Deformation on Permeability of Ottawa Sand
Mark D. Zoback,James D. Byerlee +1 more
TLDR
In this paper, high-pressure laboratory experiments have been performed in which permeability and pore-volume changes were measured during hydrostatic and triaxial deformation of Ottawa sand.Abstract:
High-pressure laboratory experiments have been performed in which permeability and pore-volume changes were measured during hydrostatic and triaxial deformation of Ottawa sand. Under hydrostatic compression, the permeability and porosity of the Ottawa sand initially decreased fairly gradually. At a confining pressure of about 600 bars, however, an abrupt onset of grain crushing and pore collapse resulted in accelerated compaction and permeability loss. In the triaxial-deformation experiments, considerable grain crushing accompanied deformation and both large decreases in pore volume and extremely large decreases in permeability occurred. At higher confining pressures, even though relatively less pore-volume decrease accompanied deformation, there was greater permeability ecrease with axial strain. Dilatancy, or an increase in pore volume with deformation, occurred near the maximum in the stress-strain curves. This dilatancy preceded failure, apparently continued uniformly into the post-failure region, and resulted in a lessened rate of permeability decrease with strain. Comparison of the permeability changes in Ottawa sand in compression and extension showed that if granular material has been subjected to sufficient deformation, fluid flow can be quite anisotropic, the permeability in the direction of maximum compression being significantly lower than the permeability normal to that direction.read more
Citations
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Journal ArticleDOI
Permeability of crystalline and argillaceous rocks
TL;DR: In this article, the authors compared laboratory, in situ, and inferred values of permeability, k, of crystalline and argillaceous rocks, and found that in situ k ranged from about 1 μd (10−14 cm2) to 100 md; this is close to the permeability of many sandstones and about 103 times greater than laboratory measurements for intact crystalline rocks.
Journal ArticleDOI
Laboratory measurement of compaction-induced permeability change in porous rocks: Implications for the generation and maintenance of pore pressure excess in the crust
TL;DR: In this paper, the dependence of pore pressure and porosity on the pore structure and its compressibility has been investigated experimentally in five sandstones with porosities ranging from 14% to 35%.
Journal ArticleDOI
Attenuation of seismic waves in dry and saturated rocks: II. Mechanisms
TL;DR: In this article, several hypothesized attenuation mechanisms are discussed in relation to published data on the effects of pressure and fluid saturation on attenuation, including friction, fluid flow, viscous relaxation, and scattering.
Journal ArticleDOI
Dilatancy, compaction, and slip instability of a fluid‐infiltrated fault
Paul Segall,James R. Rice +1 more
TL;DR: In this paper, the authors analyzed the conditions for unstable slip of a fluid infiltrated fault using a rate and state dependent friction model including the effects of dilatancy and pore compaction.
Journal ArticleDOI
The transition from brittle faulting to cataclastic flow: Permeability evolution
Wenlu Zhu,Teng-fong Wong +1 more
TL;DR: In this article, the authors investigated the influence of stress and failure mode on axial permeability of five sandstones with porosities ranging from 15% to 35% in the cataclastic flow regime.
References
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Book
Soil mechanics in engineering practice
Karl Terzaghi,Ralph B. Peck +1 more
TL;DR: In this article, the authors present a survey of the properties of soils and their properties in terms of Hydraulics of Soils, Hydraulic and Mechanical Properties of Soil Exploration Hydraulic, Mechanical, and Hydraulic properties of soil.
Journal ArticleDOI
The stress-dilatancy relation for static equilibrium of an assembly of particles in contact
TL;DR: In this paper, the authors studied the relationship between the rate of dilatancy and the maximum stress ratio for any ideal packing and showed that the Mohr-Coulomb criterion of failure is strictly applicable to a continuum and does not have general application to a discontinuous assembly of particles.
Journal ArticleDOI
Influence of Texture on Porosity and Permeability of Unconsolidated Sand
D. C. Beard,P. K. Weyl +1 more
TL;DR: In this article, an investigation was made of the relations among porosity, permeability, and texture of artificially mixed and packed sand, to determine the approximate porosity and permeability values to be expected for unconsolidated sand of eight grain-size subclasses and six sorting groups.
Journal ArticleDOI
Brittle-ductile transition in rocks
TL;DR: In this paper, the deformational characteristics of two limestones, one gabbro, and one dunite have been investigated as a function of confining pressure, and it was found that friction of these rocks and friction of granite and serpentinite studied elsewhere are nearly identical, and that the brittle-ductile transition pressure is simply the pressure at which the stress required to form a fault is equal to the pressure required to cause sliding on the fault.
Journal ArticleDOI
The Strength of Soils as Engineering Materials
TL;DR: In this article, the strength of soil is studied in relation to the failure of test scores and the effect of time on soil strength, and the difficulty of determining what is the in-situ UNDRAINED STRENGTH of a soil.