Low temperature eclogite facies metamorphism in Western Tianshan, Xinjiang

<正>According to the field occurrences and petrological study, the low temperature eclogite facies metamorphic rocks in Western Tianshan of Xinjiang can be divided into five types: (i) massive glaucophane-epidote eclogites and glaucophane-paragonite eclogites; (ii) schistose or gneissic mica eclogites; (iii) banded calcite eclogites; (iv) pillow glaucophane eclogites; (v) gar-net-omphacite quartzites. Their eclogite facies metamorphism has undergone four stages of evolution: (i) pre-peak lawsonite-blueschist facies stage, T= 350-4000℃, P= 0.7-0.9 GPa; (ii) peak eclogite facies stage, T= 530 $ 20℃, P= 1.6-1.9 GPa; (iii) retrograde epidote-blueschist facies stage, T=500-530℃, P = 0.9-1.2 GPa and (iv) retrograde blueschist-greenschist facies stage, T = 450-550℃, P = 0.7-0.8 GPa. The metamorphic PT path of Western Tianshan eclogites is characterized by clockwise ITD resulting from the subduction of Tarim plate northward to Yili-Central Tianshan plate followed by fast uplift to the surface. But there were at