Tectonic unit division and Neo-Tethys tectonic evolution in north-central Myanmar and its adjacent areas

Abstract：The study of Tethys, the southeast extension of the Tibetan plateau, has aroused great interests among geologists all over the world. However, north-central Myanmar and its adjacent areas as the extension of Yunnan-Tibet Neo-Tethys in Southeast Asia have been very insufficiently studied. Therefore, it is significant to divide tectonic units and investigate Neo-Tethys tectonic evolution under the Tethyan tectonic background based on the data available, regional comparative analysis and the determination of the extension trends of individual tectonic units and their interrelations. On the basis of the temporal-spatial distribution nature of the regional structure-rocks, the authors divided the study area into 7 third grade structural units, i.e., eastern edge of Indian continent, India-Burma range suture, west Myanmar continental block, Taguang-Myitkyina suture, Tengchong-Moulmein continental block, Luxi-Mogok suture and Baoshan-Shan Thai continental block. The three sutures were products of India-Burma range ocean, Taguang-Myitkyina ocean and Luxi-Mogok ocean respectively. Coevally, these ocean basins came to being in late Triassic, and constituted the Neo-Tethyan ocean in the Mesozoic in Southeast Asia To some extent, their formation, development, closure and consequent continent-continent or arc-continent collision constituted the basic fremework of the Meso-Cenozoic tectonic evolution in this region.