合肥盆地地质格架演化及油气条件分析

Research on the geological framework and evolution as well as hydrocarbon prospect of Hefei Basin

综合运用大地构造学及沉积学理论与方法 ,结合最新的勘探资料 ,对合肥盆地的地质构造与演化及油气地质条件进行了较系统的研究与论述。印支运动造就了盆地的统一基底和基本形态 ,其基本构造格架为“三坳围一隆” ;盆地经历了 4个演化阶段 ,其动力在早期主要源自大别山构造带 ,后期主要源自郯庐断裂带 ,其间为二者的联合控制作用 ;区内石炭—二叠纪煤系具有良好的煤型气及一定的煤层气潜力 ,中、下侏罗统和下白垩统暗色泥岩类是最具生油潜力的烃源岩系。

Based on the latest explorative data,the geological structure,evolution and the hydrocarbon geological conditions of Hefei Basin are systematically studied and discussed in this paper by means of theory and methods of tectonics and sedimentography.Indosinian Movement has resulted in the uniform basement and basic topography,the basic tectonic framework is “three depressions surrounding one uplift”.The basin is endured four evolutional phases.In the early stage of basin evolution,it is mainly controlled by Dabie Orogenic Belt,it is prominent controlled by Tanlu fracture zone in the late stage,and controlled by the combined functions in the middle stage.Permo Carboniferous coal series have relative good coal gas potential,dark mudstones in Lower Jurassic,lower part of Middle Jurassic and Lower Cretaceous are the best source rocks.Indosinian Paleo weathering crust and central uplifted structures are the most favorable hydrocarbon habitats.