Relation Between Physical Anisotropy and Microstructure of Granite

Granite contains many small defects which are preferentially oriented along three mutually perpendicular planes. These defects affect the physical properties, of the granite, e. g. P wave velocity, compressive strength, tensile strength.In this study, we are reporting the relation between the physical anisotropy and the microstructure of granite. Oshima granite was chosen for this test. P wave velocity was measured in diametric directions at 15° intervals. The diametric compression test was performed under the same condition. Three thin sections were cut (one parallel to the rift plane, one parallel to the grain plane and one other parallel to the hardway plane) to check the preferred orientation of small defects.There was a strong correlation between the strength anisotropy, the preferred orientations of open microcracks in quartz and P wave anisotropy and there was also a correlation between the tensile strength anisotropy and the healed microcracks in feldspar.