THE METAMORPHIC ROCK SERIES OF CHINA AND ITS RELATION TO CRUSTAL EVOLUTION
Basing on the materials collected during compilation of"Metamorphic Map of China(1/4000000)", this paper, firstly, gives a simple description of the main meta-morphic features and geological history of ten metamorphic provinces in China. Three main periods are distinguished about the crustal evolution of our country;1. during Archaean-early proterozoic period, the sialic crust of China was formed by vertical thickening and lateral overgrowth.By the end of early Proterozoic,the extensive cratonization gave rise to the paleo- China craton.The regional metamorphism of this period is characterized by widespread monotonous am-phibolite facies of intermediate pressure as well as some granulite-facies implying an universal high thermal-flow value in upper crust of moderate thickness.2. in middle Proterozoic-early Mesozoic period, the crust of China craton was fractured and reworked repeatedly with the development of many new en-sialic mobile belts.They are characterized by regional low-temperature dynamic metamorphism of monotonous low greenschist facies.But in some rift and sag belts with thinning and highly cracing of sialic crust, the progressive metamorphism of centre-type plays an important role.The occurrence and mineral assemblages of glaucophane greenschist belts, which are rather common in each metamorphic epochof this period, are some different from that of typical glaucophane-lawsonitefacies in subduction zone of oceanic plate.They are formed under local tectonic overpressure at closing stage of some deep sea trough controlled by deep fault.3. metamorphism of Mesozoic-Cenozoic period is characterized by the formation of Miyashiro,s"paired autamorphic belt" in southern Tibet and Taiwan. They are related to plate tectonics.