The Physical Properties of Deep Crustal Rocks.

Several results of the project stand out. First, the DSA technique provides an important method of characterizing microcracks. Second, a suite of rocks with crack porosity that varies from less than .000002 to .001 has been identified. Third, a technique was developed for the production of microcracks in rocks under controlled conditions. Fourth, techniques for preparing specimens for examination of microcracks in the SEM were developed with partial support from ONR. Sixth, new measurements of the complex dielectric properties of several igneous and metamorphic rocks, under simulated crustal conditions, provided the data necessary to estimate the electrical properties of the crust of the eastern United States.