The East Antarctic Shield records various geological processes from Archean to Phanerozoic. The Prydz Bay belt was closely related to the evolution of the Rodinia and Gondwana supercontinents, but the geological history of the region remains unclear. The mineral assemblage of the spinel-cordierite granulite from the Mirror Peninsula in the Prydz Bay belt includes spinel, cordierite, biotite, sillimanite, minor garnet, K-feldspar and ilmenite. Combined with paragenetic mineral assemblages and mineral compositions, the phase equilibrium modelling constrains peak pressure-temperature(P-T) conditions to 870~900°C, 6.3~6.9kbar, and retrograde P-T conditions to 810~820°C, 4.9~5.3kbar. Based on reintegrated spinel compositions, the formation temperature of spinel was constrained to 750~810℃, comparable with those retrograde conditions constrained using phase equilibrium modelling. Zircon grains commonly show core-mantle-rim structures in cathodoluminescence (CL) images. The core domains show a wide age range between 613±6.6Ma to 877±8.6Ma with a maximum age of 916±10.9Ma, which are younger than typical age of Greenvillian events. The bright rims of zircon grains yield a weighted mean age of 525.7±8.2Ma with a wide range of Th/U (0.06~1.23), mostly higher than 0.1. Combined with previous results, the medium- to low-pressure granulite facies metamorphism as revealed by the spinel-cordierite granulite could be interpreted to form in an orogenic process from collisional to subsequent post-collisional stage, possibly associated with the assembly of the Gondwana supercontinent.
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