Previous laser-heated diamond-anvil cell (LHDAC) experiments on (Mg, Fe)O ferropericlase yielded an MgO melting curve consistent with ab initio predictions and suggested that FeO forms a complete solid solution with MgO at least up to ~40 GPa [Du and Lee, 2014]. But the melting behavior of ferropericlase at pressures greater than 40 GPa remains poorly constrained. I have performed LHDAC experiments using in situ two-dimensional multi-wavelength imaging radiometry and ex situ chemical and textural analyses of samples melted at ~70 GPa. My results suggest that ferropericlase deviates from an ideal solid solution to possibly eutectic behavior, assuming the MgO melting curve is still predicted well by ab initio computational methods. More experiments are required to verify this phenomenon and its extent in the Earth’s mantle.
In order to better constrain the temperature profile during laser heating, we will use the TempDAC code developed by Emma Rainey (Rainey et al., 2013) to get the theoretical temperature 3D distribution around the laser heated hot spot. These data will be processed by IDL on the workstations in the YCEO Lab.