9316120 King The current generation of convection calculations indicate that including the effect of the spinel to perovskite plus magnesiowustite phase change in the convective flow calculation causes complex time-dependent flow patterns in the Rayleigh number range appropriate to the Earth. This so-called "dynamic layering" phenomenon will be investigated in a 2-D Cartesian geometry with a compressible finite element code. The PI will compare the simple thermodynamical formulation used in previous studies with a thermodynamically self-consistent formulation. He will then investigate the effect of temperature-dependent viscosity with plate-like and slab-like features in the compressible, phase change system. He will evaluate the results using radial mass flux functions and radial correlation functions. ****