中国环青藏高原新生代巨型盆山体系构造特征与含油气前景

受印度-欧亚大陆碰撞及其持续的汇聚作用影响，中国中西部地区新生代构造最为显著的特征表现为环青藏高原的巨型盆山体系及盆、山结合部位的前陆盆地（及前陆冲断带）。结合大量的地质、地球物理资料，首先提出了环青藏高原巨型盆山体系的概念，描述了其分布特征，探讨了该体系的深部构造特征和成因动力学机制。重点研究了该体系内前陆盆地的构造特征，认为该体系内前陆盆地是喜山期再生前陆盆地（及冲断带）与海西晚期-印支期周缘、弧后前陆盆地组成的叠合式前陆盆地，其原型盆地包括海西-印支期周缘前陆盆地（如塔里木盆地北部、川西、鄂尔多斯盆地西缘等）、海西-印支期弧后前陆盆地（如塔里木盆地南部等）、喜山期再生前陆盆地（如库车、塔西南、准南等）。上述两期、三种原型盆地，在喜山期冲断隆升活动作用下，形成四类叠合式前陆盆地：叠加型、新生型、改造型和早衰型。中国环青藏高原巨型盆山体系内广泛发育多个前陆冲断带，构造变形极为复杂，主要构造样式有断层相关褶皱组合、盐相关褶皱、走滑-冲断构造组合等。最后分析了该体系内前陆盆地（及前陆冲断带）的油气地质条件，认为该区油气地质条件优越、油气资源丰富，是今后中国油气勘探的重要领域。

Structure Characteristics and Petroleum-bearing Prospects of Cenozoic Cir-cum-Tibet Plateau Basin and Range System in China

Being impacted by India Eurasia continental collision and its agelong convergence，the Cenozoic tectonics of the Middle and the Western China are obviously characterized by the Circum Tibet Plateau Basin and Range System and the foreland basins including the foreland thrust belts in the basin mountain joint areas. Based on a great number of geological and geophysical data，this study first brought up the concept and the distribution features of the Circum Tibet Plateau Basin and Range System, and then discussed its deep structure characteristics and origin dynamics mechanism. Through deep investigation into the structure features of this system，this study thought those foreland basins came into being as superposed basins from the regenerated foreland basins in the Himalayan tectonic movements and circum and post arc foreland basins in the late Hercynican Indosinian orogeny, and their prototype basins included circum foreland basins in the Hercynian Indosinian orogeny （such as the northern Tarim basin， the West Sichuan basin，and the western Ordos basin，etc.）, post arc foreland basins in the Hercynian Indosinian orogeny （such as the southern Tarim basin，etc.）and the regenerated foreland basins in the Himalayan orogeny （such as the Kuqa basin，the Southwestern Tarim basin，the Huainan basin，etc.）. These three prototype basins in addition to the thrusting and uplifting movements in the Himalayan orogeny are classified into four types of superposed foreland basins：the superimposed，the neogenic，the converted，and the premature decayed. Within the Circum Tibet Plateau Basin and Range System there developed several foreland thrust belts with complex tectonic deformation and the main structures include fault correlative folds combination，salt correlative folds，strike slip thrust combination，and so on. In the end，through analysis on the geological conditions for oil and gas in the Circum Tibet Plateau Basin and Range System, this paper considers that there are such favorable conditions for abundant oil and gas resources that this area will surely be the important target for oil and gas exploration in China.