A STUDY ON THE PALEOSUTURE IN THE DABIE MOUNTAIN
大别山古缝合线的研究

The regional metamorphic belts, ophiolites and tectonics have been discussed in this paper. The EW-NWW suture line resulted from the subdu-ction of the southera Cathaysian oceanic paleoplate towards the northern Si-no-Korean continental paleoplate during the Jinning cycle, the evidence of which is given by the formation of glaucophane-schist and eclogite facies, granulite and almandine-amphibolite facies and greenschist facies which are respectively found in the southern, middle and northern parts of the area. Ophiolites are exposed along the belts of intense tectonism. They occur along Dabie geosutures and are thought to mark the sites of ancient zones of interaction between oceanic and continental crust. Thus, ophiolites are pre-served along the convergent plate margins although they are generated at the accreting plate margins.Seismological studies have made major contributions to our understanding of the structure and dynamics of the Dabie paleosuture belt.The relationship between the average thickness of the earth crust obtained from Rayleigh-wave dispersion and the surface topography is discussed. It is agreed that the crust in this area may be divided into two separate regions, the north and the south, each being an independent isostatic system at the depth of Moho discontinuity.