Metamorphic rocks with different pressure–temperature–time paths bounded by a ductile shear zone at Oyayubi ridge, Brattnipene, Sør Rondane Mountains, East Antarctica

The Sør Rondane Mountains, East Antarctica have been thought to be situated in the collision zone between and West Gondwana during final stage of amalgamation supercontinent. They are therefore recognized as a key region for understanding geological phenomena collisions testing proposed tectonic models. We identified metamorphic rocks with different pressure–temperature–time paths that bounded by ductile shear at Oyayubi ridge, Brattnipene, Mountains. Based on field microscopic observations, chemical analyses minerals, zircon U–Pb dating, sillimanite–garnet–biotite gneisses (i.e., pelitic gneisses) from higher structural level show peak metamorphism ca. 590 Ma took place under conditions 830–840 °C 0.8–0.9 GPa, these high-temperature lasted until 550 Ma. These underwent isothermal decompression then retrograde hydration lower pressure–temperature than 530 0.4 GPa In contrast, orthogneisses consist hornblende–biotite gneiss garnet–clinopyroxene levels did not undergo 600 Ma, but 570 reached 700–760 0.6–0.9 560–550 observations suggest thrusting over orthogneiss 570–550 causing prograde well uplift subsequent rapid denudation. results indicate two stages bounds units may part continental plate boundary