Abstract:
Abstract:A strongly peraluminous (SP) granites belt, extending over 100 km from east to west, is distributed 800-100 km south of the Bangong Co-Nujiang junction zone. It consists of several intrusions such as the Songmuguo intrusion and Yangxiongle intrusion. The intrusions are emplaced on both south and north sides of the Ngangzê Co-Sereba fault and involve five intrusion events. They all belong to high-K, calk-alkaline, SP granites and are post-collisional SP granites of Mid-Late Jurassic age. Study suggests that the formation of the belt is related to the southward subduction and closing of the Nyima segment of the Bangong Co-Nujiang junction zone before the Middle Jurassic. The limited length of the SP granite belt and its earlier regional emplacement time show that the Meso-Tethys is composed of multiple blocks and closed in different times.