PreMDB, a thermodynamically consistent material database as a key to geodynamic modelling

We present a tool for coupling thermochemistry with mechanics. Thermodynamic potential functions are used to calculate reversible material properties such as thermal expansion coefficient, specific heat, elastic shear modulus, bulk modulus and density. These material properties are thermodynamically self consistent. Transport properties such as thermal conductivity (diffusivity) and melt viscosity are also included, but these are derived from laboratory experiments. The transport properties are included to provide a reference database as a common standard of material properties necessary for comparing geological, geodynamic and geotechnical calculations. We validate the chemically derived elastic material properties by comparing computed seismic velocities for a pyrolitic composition to the seismic models PREM and ak135.