TECTONIC EVOLUTION AND PALEOCONTINENT RECONSTRUCYION OF QINGHAI-TIBET PLATEAU AND ITS ADJACENT AREA SINCE THE LATE PALEOZOIC

Based on the paleomagnetic data from Tibet and adjacent areas,and the studies on paleogeography,petrlogy,sedimentology and tectonic deformation,we quantitatively reconstructed the relative position and relative motion of the blocks in Tibet area. The Qiangtang block began to drift northwards rapidly in Late Carboniferous,and collided with the ancient Asian continent during Late Permian to Early Triassic.The Gangdise block separated from the Gondwana continent in late Triassic,and collided with the Qiangtang block during Early-Late Cretaceous.The Himalayan block separated from the Gondwana continent in Late Jurassic,and began to drift northwards rapidly in Late Cretaceous,and collided with the Gangdise block during Late Cretaceous to Early Tertiary.