Department of Geology and Mineralogy, Faculty of Science, Hokkaido University
抄録(英)
Several islands in the west of Langhovde (69°08′-69°17′S, 39°24′-39°36′E), East Antarctica, are underlain by granulite-facies metamorphic rocks. Among them pyroxene gneiss is the most dominant rock type. It includes garnet-bearing layers, in which orthopyroxene, clinopyroxene, garnet and hornblende are present in equilibrium. These minerals are generally rich in Fe, reflecting the bulk chemistry of the host rocks. Especially, the orthopyroxenes in two specimens of pyroxene gneiss have Fe/(Fe+Mn+Mg) ratios higher than 0.9. The stability field of such Fe-rich orthopyroxenes has been estimated to be more than 9kb at 800℃. On the other hand, the calculated results by the geothermometers using orthopyroxene-clinopyroxene and garnet-clinopyroxene pairs and the geobarometers using a garnet-orthopyroxene-plagioclase association range 750-800℃ and 7-8kb.
雑誌書誌ID
AA00733561
雑誌名
Memoirs of National Institute of Polar Research. Special issue