北淮阳构造带可燃天然气的发现与合肥盆地油气远景分析

北淮阳构造带由一系列向北逆冲推覆的构造岩片组成，是建立大别山造山带和合肥盆地构造关系的纽带。在大别造山带内发现的可燃天然气和发生燃烧的隧道具有明显的区域性，集中分布于磨子潭—晓天断裂以南的北大别杂岩带和信阳－舒城断裂附近的早石炭世变质石英片岩中，磨子潭—晓天断裂和信阳－舒城断裂是连通深部的气源通道断裂；推覆体之下的寒武系凤台组和北淮阳型石炭系两套海相烃源岩是隧道可燃天然气的主力气源岩，其中下寒武统凤台组烃源岩具有高碳、高“Ro”、高Tmax、低氯仿“A”的特点，已进入热演化的过成熟阶段；北淮阳型石炭系烃源岩有机质丰度高，以Ⅲ型干酪根为主，热演化程度很高，大量的油气已经生成，最重要的是研究其成烃过程与圈闭配套史的关系。大别造山带隧道可燃天然气的发现展示了合肥盆地区深部海相层系良好的勘探前景，因此下步勘探重心应从“中新生代盆地系统”转移到“深部海相层系”，以寻找“古生古储”或“古生新储”类型油气藏为主。

Genetic Mechanism of the Beihuaiyang Tectonic Belt and Oil-Gas Potential

The Beihuaiyang tectonic belt is composed of a series of north-striking thrust slices,and links the Dabieshan orogenic belt and the Hefei Basin together.Combustible gas and burned tunnels founded in Dabie orogenic belt have distinct regional nature,and most of them distributed in complex zone of the north Dabie orogenic belt which located in the south of Mozitan-Xiaotian fault and the gneiss from the Lower Carboniferous which is close to the Xinyang-Shucheng fault.These two faults provide source passage whi...