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Creep, compaction and the weak rheology of major faults

January 1, 1992

Field and laboratory observations suggest that the porosity within fault zones varies over earthquake cycles so that fluid pressure is in long-term equilibrium with hydrostatic fluid pressure in the country rock. Between earthquakes, ductile creep compacts the fault zone, increasing fluid pressure, and finally allowing frictional failure at relatively low shear stress. Earthquake faulting restores porosity and decreases fluid pressure to below hydrostatic. This mechanism may explain why major faults, such as the San Andreas system, are weak.

Publication Year 1992
Title Creep, compaction and the weak rheology of major faults
Authors Norman H. Sleep, M.L. Blanpied
Publication Type Article
Publication Subtype Journal Article
Series Title Nature
Index ID 70017260
Record Source USGS Publications Warehouse
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