Rock property measurements and analysis of selected igneous, sedimentary, and metamorphic rocks from worldwide localities
Dry bulk density and grain density measurements were made on 182 samples of igneous, sedimentary, and metamorphic rocks from various world-wide localities. Total porosity values and both water-accessible and helium-accessible porosities were calculated from the density data. Magnetic susceptibility measurements were made on the solid samples and permeability and streaming potentials were concurrently measured on most samples. Dry bulk densities obtained using two methods of volume determination, namely direct measurement and Archlmedes principle, were nearly equivalent for most samples. Grain densities obtained on powdered samples were typically greater than grain densities obtained on solid samples, but differences were usually small. Sedimentary rocks had the highest percentage of occluded porosity per rock volume whereas metamorphic rocks had the highest percentage of occluded porosity per total porosity. There was no apparent direct relationship between permeability and streaming potential for most samples, although there were indications of such a relationship in the rock group consisting of granites, aplites, and syenites. Most rock types or groups of similar rock types of low permeability had, when averaged, comparable levels of streaming potential per unit of permeability. Three calcite samples had negative streaming potentials.