Summary
From the space distribution of P- and S-wave velocities, determined at a hydrostatic pressure of 1 GPa, complete sets of elastic constants were calculated for the Twin Sisters dunite. It was found that orthorhombic symmetry is a reasonable approximation for the dunite sample; with one exception the deviations of the individual constants, determined from different waves, do not exceed a few percent. As a seismological application a simple model of a 120 km thick lithosphere, formed by the dunite, was considered for calculating the differences in the time arrivals of SV and SH waves. The greatest time differences, about 3s, were obtained in the vertical plane containing the direction of the greatest P-wave velocity, however, for the real lithosphere we estimate effects which only cause differences of the order of 1s.
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Babuška, V., Šílený, J. Velocity anisotropy and symmetry of dunite fabric. Stud Geophys Geod 25, 231–244 (1981). https://doi.org/10.1007/BF01591935
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DOI: https://doi.org/10.1007/BF01591935