2005 Volume 27 Issue 1 Pages 41-51
An experimental apparatus has been developed which simulates pore-fluid induced slip on a preexisting fracture. Experiments conducted using the apparatus yield insights into the mechanisms of shear slip induced by fluid injection and relationship between slip behavior and fluid flow. The apparatus construction allows injection of pore fluid directly into a pre-existing fracture in a cylindrical rock sample. Confining pressures and pore pressures up to 25 MPa and 40 MPa, respectively, can be adjusted to impose different stress on the sample. A micro-mass flow meter enables precise measurement of volume of fluid flow into the fracture. Preliminary experimental results are presented which confirm the abilities of the apparatus. Preliminary experimental result shows a characteristic intermittent slip and fluctuation in fluid flow synchronizing with the intermittent slip, implying significant effects of pore fluid injected on the shear slip of a pre-existing fracture.
