1. Elastic Properties of Rocks and Minerals

Abstract

Publisher Summary Elastic properties are desired as a function of several parameters, including pressure, temperature, pore fluid pressure, nonhydrostatic stress, and failure history. Acoustic velocities are generally measured for these samples by ultrasonic transmission techniques. Often the experiments are defined to determine both the acoustic velocities and acoustic attenuation. This chapter discusses all of these experimental techniques with particular emphasis on their utility in addressing earth science problems. Each of the subjects has, at one time or another, been the focus of broad and careful reviews. The chapter demonstrates the important considerations in each of the experimental approaches. The major experimental restriction is imposed by the availability of suitable samples. Only a few relevant minerals occur naturally as large single crystals. Two types of experimental responses have been made to these extremes in sample availability. One has been to sinter many crystallites to form a polycrystalline sample. Then ultrasonic transmission measurements are made on the aggregate. The second approach has been to develop single-crystal methods that require smaller samples than were needed previously. To this end, ultrasonic transmission and resonance techniques have been used for samples of millimeter dimensions, and Brillouin spectroscopy has proved useful for elasticity characterizations for samples with dimensions of tens of micrometers.