海塔盆地主要发育南二段和南三段烃源岩,二者在沉积特征和结构特征上均存在较大差异。为了搞清这两套烃源岩的形成背景及控藏作用,从盆地构造演化角度出发分析不同时期洼槽的结构特征,进而分析洼槽与烃源岩的关系。研究表明,南二段和南三段烃源岩分别形成于被动裂陷盆地和主动裂陷盆地时期,这两个时期形成的洼槽其结构分别为“泛盆”结构和多个半地堑构成的“复式小型断陷湖盆群”结构。两期不同结构的洼槽均控制了各自烃源岩层的分布及地层结构特征,从而决定了油气近源聚集且分别为短距离侧向运移和短距离垂向运移的规律。南二段烃源岩对已发现油气的贡献要好于南三段烃源岩。
HailerTamtsag Basin mainly developed Nanerduan and Nansanduan hydrocarbon source rocks,They both in sedimentary characteristics and structure characteristics were put in bigger difference.In order to make clear the two sets of source rocks formation background and the role of controlled oil reservoir,from the basin structure evolution perspective analysis different features of the structure of troughs,and then analysis the relationship of the troughs and the hydrocarbon source rocks.Research shows that the hydrocarbon source rocks of Nanerduan and Nansnaduan are formed in the passive rift basin and active rift basin period.The structure of the two period formation are “widely basin” and several half grabens composed the “complex the small faulted basins group” structure.Two issue of the different structural troughs both control the hydrocarbon source rocks distribution and strata structure features,and then decide oil and gas respectively lateral migration and short vertical migration to gathered near the source rocks.It has found that the contribution of oil and gas in Nanerduan hydrocarbon source rocks is better than Nansanduan hydrocarbon source rocks.