THE ATTENUATION OF HIGH-AMPLITUDE WAVES IN ROCKS

Abstract

The pin-contactor method was modified so that it could be used to measure coefficients of absorption of high-amplitude waves in cylinders of rocks and metals. Experiments performed with granite, marble, and aluminum showed that the coefficients of absorption for marble and aluminum for pressures below 100 kb are more than three times that for granite. Also, for pressures greater than 22 kb the absorption coefficient for marble is more than twice that for pressures below this level. It should be emphasized that the absolute values of the absorption coefficients found in these experiments depend on the geometry; however, the relative values indicate the extent of the differences in the properties of the rocks. The compressibilities of both marble and granite were found to be constant for pressures in the 2 to 100 kb range. The results of these experiments and similar ones could lead to a better understanding of how the energy of explosions can be coupled into seismic energy more efficiently.