9528965 McCALL This research is a theoretical investigation of the non-linear elastic properties of rocks. The central construct of this paradigm for the description of the elastic properties of consolidated materials is the Preisach-Mayergoyz space, the pressure space in which a density of microscopic mechanical units is tracked as a function of the characteristic pressures at which cracks are opened or closed. This theory can be used to predict the stress-strain equation of state (with hysteresis and discrete memory), the ratio of static to dynamic modulus, and the amplitude of second harmonic generation within a sample. A successful theory of nonlinear elastic behavior in rock (and other consolidated materials) will provide a necessary tool for turning nonlinear experimental investigation into quantitative measures of rock properties. Non-linear elastic behavior of rocks is an important component of theories of the state of rock prior to earthquake rupture. This research is a component of the National Earthquake Hazard Reduction Program. ***
