Anisotropy of thermal diffusivity in olivine, pyroxene and dunite.

The thermal diffusivities along three crystallographic orientations are measured for olivine and pyroxene up to 1250K. The result shows that the anisotropy amounts to about 70%. The anisotropy is attributed mostly to anisotropy of mean free path of phonon. The anisotropy of thermal conductivity and thermal diffusivity in dunite is measured and is discussed on the basis of preferred orientation and the anisotropy of constituent minerals.