A Method for Estimating the Rheological Properties of Fractured Rock Inside a Shear Zone

This paper is concerned with the creep properties of fractured rock in a shear zone. We consider a cube rock model which consists of the rock matrix and cracks. A finite element method with discontinuous deformation analysis (DDA) is used to simulate the creep response of the fractured rock sample. The DDA is used to describe the interactions among the contacting blocks at their interfaces (cracks). In all numerical simulations of the creep test, the strain rates are those typical values corresponding to effective viscosities of 10 17 –10 19 Pa s, similar to that obtained from geophysical observations in a shear zone. The effects of temperature, confining pressure, crack length and tilt on the creep responses are examined using the simulation results. The numerical results indicate that our method is a useful tool for simulating creep deformation of fractured rock. The present study represents an effort to use a numerical method to simulate the rheological properties of fractured rock in the field of micro-geodynamics.