The principal investigators will study minerals and mineral stabilities in the chemical system iron oxide-titanium oxide- alumina-silica-water. In particular, the thermochemical and mixing properties of Fe-staurolite, the stability of Fe-cordierite, and the hematite-ilmenite solvus will be investigated. The staurolite and cordierite results should yield geothermobarometers useful in the study of pelitic rock metamorphism. The hematite-ilmenite work will allow estimates of oxygen fugacity and hence water fraction of fluids in graphitic pelites. It may also allow estimation of oxygen fugacity for rocks in which hemoilmenite occurs. Overall, this research will allow geologists to better estimate the conditions to which aluminous rocks have been subjected during metamorphism.
