中国陆上海相沉积盆地主要经历了早古生代末、晚古生代-早中生代和晚新生代3期重大构造变革,深刻地影响了海相沉积盆地的油气生成、运移、聚集与分布,使得油气富集、分布规律变得非常复杂.塔里木盆地是中国海相层系多期油气成藏的典型实例.早古生代的构造格局奠定了塔里木盆地海相油气形成的地质基础,但油藏多已遭破坏,现今仅残存沥青.晚古生代,满加尔凹陷西部奥陶系烃源岩进入生烃高峰并在南北两大隆起部位持续充注成藏,随后早中生代发育的构造挤压变形与抬升剥蚀使这期聚集的油气遭受了明显的生物降解.晚新生代盆缘改造和陆相磨拉石建造的叠置加速了台盆区二次裂解气的生成,溶解了早期聚集的原油,形成了独特的大型凝析气藏.3期主要构造变革不但控制了海相沉积盆地形成、烃源岩沉积及其热演化、储集岩沉积与储集层形成,也深刻影响了油气运聚成藏和调整改造的整个过程.%Subaerial marine sedimentary basins in China have undergone three phases of important tectonic changes in the end of Early Paleozoic, Late Paleozoic-Early Mesozoic and Late Cenozoic.These tectonic changes have exerted strong impacts on the hydrocarbon generation, migration, accumulation and on the occurrence and distribution of hydrocarbon reservoirs.The Tarim Basin is a typical example of multiphase hydrocarbon accumulations in a marine basin of China.The Early Paleozoic tectonic framework laid a geological basis for the marine hydrocarbon formation of the Tarim Basin, but most of them were destroyed later due to frequent tectonic movements and only bitumen is left at present.In the Late Paleozoic, the Ordovician source rock located in the western Manjar Sag entered the peak generation and hydrocarbons successively accumulated at its southern and northern uplifted positions.The tectonic compressional deformation developed in the Early Mesozoic and the subsequent uplifted denudation allowed hydrocarbons accumulated at this phase to suffer from bacterial degradation.In the Late Cenozoic, the superimposition of basinal margin reconstruction and terrestrial molasse formation quickened the formation of secondary cracking gases in the platform of the basin, the influx of deep natural gases dissolved crude oils accumulated early and a unique large-scale condensate pool was then formed.The three tectonic changes controlled not only the formation of the marine basin, the sedimentation and evolution of source rocks, and the formation of reservoirs, but also the accumulation process and adjustment of hydrocarbons in the marine sedimentary basin.
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