R8: Metamorphic rocks and tectonics

2:30 PM - 2:45 PM JST(5:30 AM - 5:45 AM UTC)

[R8-09] Pressure-Temperature path of a pelitic gneiss from Menipa, Sør Rondane Mountains, East Antarctica

*Tetsuo Kawakami¹, Masayasu Suzuki¹ (1. Kyoto Uni. Sci.)

Keywords:

Continental collision zone,Metamorphism,Pressure-temperature path,Granulite,Antarctica

Metamorphic pressure-temperature (P-T) conditions of a Bt-Sil-Grt geniss from Menipa, Sor Rondane Mountains, East Antarctica was determined. Grt porphyroblasts include kyanite and Sil at the rim, along with Rt. Application of the Zr-in-Rt geothermometer to Rt enclosed in the Grt rim gave 750-870 ^oC at 0.9-1.15 GPa. Application of Grt-Bt geothermometer and GASP geobarometer to the Grt rim and secondary Pl and Bt coexisting with Sil and Qz gave 610 ^oC at 0.38 GPa. Based on these estimates, the P-T path for the Menipa rocks is likely a clockwise path.