Fluid exerts significant mechanical and chemical effects on virtually all crustal processes. Recent observations suggest that elevated pore pressures may exist in a range of crustal environments, including mature fault zones and accretionary complexes. Quantitative modeling of the generation and maintenance of overpressure in most of these problems requires a fundamental understanding of the relation among permeability, porosity and stress. This is an experimental program to determine permeability and porosity changes in porous aggregates (sandstones, hot pressed quartz, and ODP samples) under triaxial compression conditions. Microstructural observations, acoustic emission measurements and percolation modeling will be integrated in the study so as to gain a fundamental physical understanding of compaction/dilatancy and hydraulic transport in the crust.
