What kind of information about stresses and rheology is supplied by fracture processes in the Earth's crust?

摘要

Contrary to popular belief, fracture processes, when their spatial expression is sufficiently detailed, supply information not only about stresses, but also about the effective rheological properties of the rock mass. Based on the fracture pattern geometry, the trajectories of principal stresses are plotted, which in turn may allow rejecting definitely inappropriate classes of the effective rheological models. By studying kinematics of fracture processes (and, in general, by analysis of any type of kinematic data giving rise to determination of the inhomogeneous deformations), it is possible to identify specific constitutive relations within the rheological classes that are compatible with the observations and equilibrium conditions. The common practice of prescribing a priori rules of how the effective geophysical medium responds to the applied load should be replaced by the development of approaches to extracting these rules from observations.