Metamorphic rocks of the Cape Hinode district, East Antarctica

摘要

Microprobe analyses of amphiboles, biotites, clinopyroxenes, feldspars, garnets and Fe-Ti oxides in various metamorphic rocks of the Cape Hinode district, East Antarctica are presented. The analytical results of these minerals show that they crystallized under the condition of amphibolite facies. The composition of hornblendes belongs to a low pressure type, and indicates that they might have crystallized at about 5kb or lower. Garnet-biotite geothermometry reveals that the estimated temperature is about 650℃. Biotite included in garnet crystal in sillimanite-garnet-biotite gneiss has the composition rich in Mg and poor in Ti and might have been formed at lower temperature than matrix ones.