On the eclogite facies metamorphism in the Dabie Mountains

Eclogite facies rocks from the Dabie Mountains are mainly composed of garnet peridotite, eclogite, garnet phengite schist, eclogitic gneiss, garnet jadeite quartzite and eclogitic marble, which often occurs within granitic gneisses. The paragenetic sequence in eclogite indicates that eclogite facies rocks experienced progressive metamorphism from epidote amphibolite facies to coesite eclogite facies and retrograde metamorphism from amphibole eclogite facies through epidote amphibolite facies to greenschist facies. Granitic gneisses and metamorphosed volcanic sedimentary rocks were not subjected to ultrahigh pressure metamorphism, but they together with eclogite facies rocks underwent the same epidote amphibolite facies metamorphic event. This may imply that the two rock units were juxtaposed at crustal levels during the late continental collision in the Dabie Mountains.