LATE PROTEROZOIC TERRANE TECTONICS IN THE CENTRAL JIANGNAN BELT, SOUTHEAST CHINA

The Huaiyu and Jiuling terranes in the central Jiangnan belt, south Ch ina, are separated by the Dongxiang-Shexian shear zone. An Upper Prote rozoic ophiolite-bearing melange is dispersed along the contact. Isoto pic ages of mafic and ultramafic rocks within the melange cluster arou nd 1000 Ma (Sm-Nd method). Glaucophanes from blueschist yield an isoto pic age of 866 Ma (K-Ar method), interpreted to date the timing of col lision. The melange and terranes underwent regional metamorphism durin g the Late Proterozoic. The resulting foliation was later crosscut by a Late Proterzoic sinistral oblique normal shear along the suture zone . Clastic sediments were unconformably deposited over both terranes du ring the Sinian (latest Proterozoic).