| Based on plenteous field work and detailed petrological study, The HP(high pressure) - UHP(ultra high pressure) metamorphism terrains of Jiangling in eastern Dabie mountain are comprised of large blocks of gneisses, mica-schists and eclogites. These garnet-mica schists generally contain garnet, phengite, biotite, plagioclase, quartz, rutile and small amount of epidote and hornblende. Based on petrography and the phases equilibria study in NCKMnFMASH system, it can be testified that the mineral assemblages of this region is not in equilibrium. The composition zonation appears pervasively in garnets. Muscovite is divided into phengite and common muscovite. Plagioclase could also divided into two kinds: albite and oligoclase. The earlier mineral assemblages, represented by garnet and phengite, reflect HP-UHP conditions. The component isoline of garnet and the Si content of phengite can give the P-T condition: 580~600℃, 2.6~2.8 GPa. It is the first time getting UHP metamorphism conditions from main minerals in mica-schists. The content of the zone of garnet remarks the earlier progressive metamorphic process, and glaucophane, jade and lawsonite could appear in this period. The P-T condition provided by the later mineral assemblages, represented by biotite and plagioclase, is 620~635℃,0.9~1.1 GPa, which is belonged to HP amphibolite facies. The main mineral assemblages of mica-schists in Jiangling region can also remark a complete progress of HP-UHP metamorphism.
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