To clarify the deformation and slip mechanisms in seismogenic regions, we designed and developed a new gas-medium, high-pressure and high-temperature apparatus. The apparatus can attain confining pressures up to 200 MPa by argon gas, temperatures up to 800°C, and pore pressures up to 200 MPa by argon gas or water. Confining and pore pressures can be applied and servo-controlled. We report preliminary test results. The stress-strain curve of granite sample at a confining pressure of 200 MPa and a temperature of 800°C shows a ductile behavior. One of the friction parameters, the a-b value defined as the velocity dependence of steady-state friction, of quartz gouge was measured under hydrothermal conditions.
