R8: Metamorphic rocks and tectonics

[R8P-02] Garnet-forming partial melting in the presence of a fluid phase: an example from a pelitic migmatite in the Higo metamorphic terrane

[Presentation award entry]

*Natsumi Yoshimoto¹, Tetsuo Kawakami¹, Satoshi Hojo (1. Kyoto Univ.)

Keywords:fluid, nanogranites, partial melting

The garnet in the pelitic migmatite from Zone D of the Higo metamorphic terrane includes nanogranite inclusions (NI) and carbonate- and hydrous-mineral-rich multiphase inclusions (MSI) in the mantle. The MSI rarely accompany CO₂ and graphite. The MSI is likely a retrograde reaction product between C-O-H fluids and host garnet. Therefore, coexistence of the MSI and NI shows that C-O-H fluid was present during the garnet-forming partial melting in the Zone D of Higo metamorphic terrane.