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.%青藏高原东南部特提斯研究是世界地质研究的热点之一,而缅甸及邻区作为滇藏新特提斯在东南亚的延伸地段,研究相对薄弱而分散.因此在特提斯构造域背景下,结合前人研究资料,通过区域对比分析,厘定区内各构造单元的延伸趋势及其相互关系,进行构造单元划分并论述新特提斯构造演化具有重要意义.基于区域构造-岩石组合的分布发育及时空属性特征,本文将该区划分为7个三级构造单元,自西向东依次为印度大陆东缘、印缅山脉结合带、西缅陆块、太公—密支那结合带、腾冲—毛淡棉陆块、潞西—抹谷结合带和保山-掸泰陆块.三条结合带的前身分别是该区新特提斯印缅山脉洋、太公—密支那洋和潞西—抹谷洋.这三支洋盆在晚三叠世时近同时开启,其形成、演化及闭合后的弧-陆、陆-陆碰撞拼合过程,构成了研究区中新生代构造环境演化的基本格局.
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