The transition from brittle faulting to cataclastic flow in porous sandstones: Mechanical deformation

Triaxial compression experiments were conducted to investigate the inelastic and failure behavior of six sandstones with porosities ranging from 15% to 35%. A broad range of effective pressures was used so that the transition in failure mode from brittle faulting to cataclastic flow could be observed. In the brittle faulting regime, shear‐induced dilation initiates in the prepeak stage at a stress level C ' which increases with effective mean...