Equation of state fits to the lower mantle and outer core
Abstract
The lower mantle and outer core are subjected to tests for homogeneity and adiabaticity. An earth model is used which is based on the inversion of body waves and Qcorrected normalmode data. Homogeneous regions are found at radii between 5125 and 4825 km, 4600 and 3850 km, and 3200 and 2200 km. The lower mantle and outer core are inhomogeneous on the whole and are only homogeneous in the above local regions. Finitestrain and atomistic equations of state are fit to the homogeneous regions. The apparent convergence of the finitestrain relations is examined to judge their applicability to a given region. In some cases the observed pressure derivatives of the elastic moduli are used as additional constraints. The effect of minor deviations from adiabaticity on the extrapolations is also considered. An ensemble of zeropressure values of the density and seismic velocities are found for these regions. The range of extrapolated values from these several approaches provides a measure of uncertainties involved.
 Publication:

Physics of the Earth and Planetary Interiors
 Pub Date:
 September 1978
 DOI:
 10.1016/00319201(78)900560
 Bibcode:
 1978PEPI...17..147B
 Keywords:

 Earth Core;
 Earth Mantle;
 Earth Planetary Structure;
 Equations Of State;
 Seismic Waves;
 Adiabatic Conditions;
 Bulk Modulus;
 Density Distribution;
 Extrapolation;
 Homogeneity;
 Mathematical Models;
 Modulus Of Elasticity;
 Pressure Effects;
 Geophysics