TY - JOUR
T1 - Calculated elastic constants and anisotropy of Mg2SiO4 spinel at high pressure
AU - Kiefer, Boris
AU - Stixrude, Lars
AU - Wentzcovitch, Renata M.
PY - 1997
Y1 - 1997
N2 - We calculated the elastic properties of Mg2SiO4 spinel, using the plane-wave pseudopotential method. The athermal elastic constants were calculated directly from the stress-strain relations up to 30 GPa, which encompasses the. experimentally observed stability field of spinel. The calculated elastic constants are in very good agreement with Brillouin scattering data at zero pressure. We calculated the isotropically averaged elastic wave velocities and the anisotropy from our single crystal elastic constants. We find that the elastic anisotropy is weak (azimuthal and polarization anisotropy of S-waves: 5%, azimuthal P-wave anisotropy: 2.5%, at zero pressure) compared to other silicates and oxides. The anisotropy decreases initially with increasing pressure, changing sign at 17GPa before increasing in magnitude at higher pressures. At typical pressures of the earth's transition zone (20-25 GPa), the elastic anisotropy is 1% and 2% for P- and S-waves respectively.
AB - We calculated the elastic properties of Mg2SiO4 spinel, using the plane-wave pseudopotential method. The athermal elastic constants were calculated directly from the stress-strain relations up to 30 GPa, which encompasses the. experimentally observed stability field of spinel. The calculated elastic constants are in very good agreement with Brillouin scattering data at zero pressure. We calculated the isotropically averaged elastic wave velocities and the anisotropy from our single crystal elastic constants. We find that the elastic anisotropy is weak (azimuthal and polarization anisotropy of S-waves: 5%, azimuthal P-wave anisotropy: 2.5%, at zero pressure) compared to other silicates and oxides. The anisotropy decreases initially with increasing pressure, changing sign at 17GPa before increasing in magnitude at higher pressures. At typical pressures of the earth's transition zone (20-25 GPa), the elastic anisotropy is 1% and 2% for P- and S-waves respectively.
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U2 - 10.1029/97GL02975
DO - 10.1029/97GL02975
M3 - Article
AN - SCOPUS:0031277806
VL - 24
SP - 2841
EP - 2844
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 22
M1 - 97GL02975
ER -