Distribution and Research Significance of Ophiolite in Brahmaputra Suture Zone, Southern Tibet

The Brahmaputra Suture Zone is one of the important suture zones in the Qinghai-Xizang Plateau,located in the southern Qinghai-Xizang Plateau,and the ophiolite is its main body.According to the outcropped size,the lithologic sequence and emplacement time of ophiolite,the Brahmaputra Suture Zone is divided into eastern,middle,and western segments approximately.There exist some differences in the size of ophiolites.The western segment is divided into two ophiolites zones and has the largest size,followed by the middle segment and the eastern segment.There are relatively complete lithologic sequence of ophiolite in the Shigatse of middle segment and Luobusha of eastern segment,but there is not any complete rock profile because of no ophiolites except for Shigatse and Luobusha.In addition,there exist also a difference in the ophiolites formation and emplacement.The eastern,western,and middle segment was formed mainly in the Late Jurassic-Early Cretaceous,but the middle segment was formed is earlier than the other two segments,from Middle Triassic to Early Cretaceous.