Permalink : http://hdl.handle.net/2115/36705

The mode of occurrence and chemical composition of garnet amphibolite in the Momose-Mizunashi district of the Hida Metamorphic Belt are described. The masses of garnet ampibolite form thin fusiform bodies whose occurrence is concordant with surrounding pelitic and basic gneisses. Formation of garnets is inferred to depend on chemical speciality of the original rocks such as high ΣFeO/MgO and low CaO/Al2O3, ratio. They are classified into two kinds of garnet amphibolite according to CaO content in garnet, i.e., one comparatively low in the CaO content, and the other rather high in the CaO content. The occurrence of Ca-rich almandine amphibolite seems to imply that the metamorphic condition in the Momose-Mizunashi district belongs to slightly higher pressure type than most prevailing metamorphic conditions in the Hida Metamorphic Belt.