Premium
A model for the variation in permeability of clay‐bearing fault gouge with depth in the brittle crust
Author(s) -
Faulkner D. R.
Publication year - 2004
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2004gl020736
Subject(s) - permeability (electromagnetism) , fault gouge , brittleness , pore water pressure , geology , overburden pressure , crust , geotechnical engineering , mineralogy , thermodynamics , materials science , fault (geology) , composite material , chemistry , geochemistry , physics , seismology , biochemistry , membrane
A model of the variation in permeability of clay‐bearing fault gouge in the brittle crust is presented. Factors affecting the permeability from laboratory experiments are considered and quantified. These are pressure, temperature and permeating fluid. Effective pressure () and temperature ( T ) effects on permeability ( k ) are described by k = k 0 exp(−0.01Δ)exp(−0.01Δ T ) where k 0 is a reference permeability at a particular temperature and pressure. At low temperatures (<80°C), with aqueous pore fluids, the above relation is modified to k = k 0 exp(−0.01Δ)exp(−0.01Δ T ) in order to describe low temperature (less than a critical temperature, T c , of 80°C) inferred physicochemical interactions between pore fluids and the fault gouge. The model is used to predict the variation in permeability as a function of depth for different ratios (λ) of pore fluid pressure to confining pressure.