Temperature derivatives of elastic moduli of MgSiO3 perovskite

[1] Elastic properties of polycrystalline MgSiO3 perovskite were determined by means of resonance sphere technique at temperatures from 258 to 318 K under atmospheric pressure. The temperature derivatives of adiabatic bulk (∂KS/∂T)P and shear moduli (∂G/∂T)P are −0.029(2) GPa/K and −0.024(1) GPa/K, respectively. Applying the present results in interpretation of seismological observations, we suggest that the chemical composition of the earth's lower mantle is pyrolitic at the potential temperature of 1600 K.