【摘要】 通过对鄂尔多斯地区晚古生代沉积盆地中天然气聚集与地质作用的研究认为,山西期-下石盒子期之所以成为鄂尔多斯上古生界主要产气层位,其地质因素与这一时期陆内盆地的扩张演化及其相应的沉积作用有关。这种关系表现在盆地处于下降时期,河流的垂向侵蚀作用大于侧向侵蚀,有充足的物源、有较大的可容空间,盆地的充填作用大于盆地扩张作用,易于形成良好的储层;而在超长周期层序的晚期,基准面旋回由上升向下降转化,也形成良好的储集砂体。更多还原

【Abstract】 It is well known that the late Palaeozoic Shanxi and Xiashihezi Formations are the main gas-generating strata in the Ordos basin, China. Based on the study of the relationship between the law of gas gathering and geologic agent in the basin, the authors think that the spreading of intracontinent basins and the sedimentation are the main geologic factors in the course of gas gathering. This shows that verticl erosion is stronger than lateral erosion in the river. The river provides rich material resources and bigger accomodation space.The filling action is stronger than the spreading action during the declining of the basin. So, good reservoirs can easily form. Basin-level cycle from ascending to declining can offer better reservoir sand bodies in the late ultra-long period stratigraphic sequence.更多还原