Earth and Planetary Science
EPS Geophysics

FEB 2006 - Plastic deformation of MgGeO3 post-perovskite at lower mantle pressures

In their recent Science paper (reprint), S. Merkel, A. Kubo, L. Miyagi, S. Speziale, T. Duffy, H.-k. Mao, and Rudy Wenk investigate the deformation behavior of germanate post-perovskite at pressures beyond 100 GPa. From the pattern of preferred orientation they determine that slip (100) and (110) slip is dominant. With this experimental information they model seismic anisotropy at the core-mantle boundary and suggest that perovskite contributes about 4% to shear wave splitting in D", with an oblique polarization.