| Rock fabrics deduced from either the anisotropy of magnetic susceptibility (AMS) or of seismic anisotropy have been widely discussed. Ophiolite from the Pindos and Vourinos Island in Greece is to be explored if there are some correlations between these characteristics. Laboratory measurements include compressional and shear-wave velocities at confining pressures to 300 MPa, density, velocity anisotropy, and shear-wave splitting, which all generally decrease with increasing degree of serpentinization. In contrast, the Vp/Vs ratio and the Poisson's ratio are inversely correlated with an increasing degree of serpentinization. Magnetic fabrics, sensitive indicators of low-intensity strain, were further obtained from AMS measurements on the same samples. The directions of acoustic and magnetic anisotropy compare favorably. These results motivate the development of additional methods to use the magnetic fabric, as deduced from simple and fast AMS measurements, as a proxy for finding the directions of elastic anisotropy in traditional ultrasonic laboratory methods. |
