Determination of Intensive Variables in Medium to High Grade Metamorphism of Pelitic Rocks

主要研究人员将研究氧化铁-氧化钛-氧化铝-二氧化硅-水化学体系中的矿物和矿物稳定性。重点研究了铁-橄榄石的热化学性质和混合性质、铁-堇青石的稳定性以及赤铁矿-钛铁矿溶液。从橄榄石和堇青石的结果可以得出对泥质岩石变质作用研究有用的地温晴雨表。赤铁矿-钛铁矿的工作将允许估计氧逸度，从而在石墨岩浆岩流体的水分数。它也可以用来估计含血红铁矿的岩石的氧逸度。总的来说，这项研究将使地质学家能够更好地估计铝质岩石在变质作用期间所受的条件。

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.