为了认识沉积充填与大面积成藏的关系,根据大量的野外露头和钻井资料,对鄂尔多斯盆地北部上古生界的物源体系和砂体发育特征进行研究.结果表明:本溪一太原期的陆表海阶段物源供给有限,小型潮控三角洲与大面积潮坪交错发育;山西一下石盒子期为陆内坳陷盆地形成发展期,物源供给充分,大型浅水三角洲在宽缓的斜坡上大面积聚砂；上石盒子期盆地进入成熟稳定阶段,坡降进一步降低,发育聚泥为主的网状河三角洲;在宽缓的古地貌背景下多河道浅水三角洲的频繁进退和侧向迁移,使多物源供砂、多水系输砂和缓斜坡聚砂组成的“源-输-汇”三元耦合聚砂系统形成了大面积立体网毯状砂体,为岩性-地层圈闭小而多、大面积分布奠定了基础,成就了鄂尔多斯盆地上古生界“满盆生气、到处含气、岩性控气”的富气规律.%The Neopaleozoic lithostratigraphic hydrocarbon reservoir is a hot spot of exploration in Ordos Basin. In order to recognize the relationship between sedimentary filling and large-area reservoirs distribution, based on abundant data of outcrops and well-drillings, the characteristics of provenance and sand body of upper Paleozoic in north Ordos Basin were researched. The results show that during the period of Benxi and Taiyuan, elastics supply was inadequate, and the margin of epeiric sea was filled by small-sized tide dominate delta and broadly tide flat. During the period of Shanxi and Shangshihezi, elastics supply was abundant, and Ordos intercratonic depression basin formed and sand was widely accumulated by large-scale shallow water delta. During the period of Xiashihezi of basin maturity phase, its slope gradient decreased, and mass of fine grained sediment was deposited by anastomosed river delta. The sandy accumulation system of " provenance-transportation-aggregation" ternary factors coupling charactered by multi-provenances, multi-drainage shallow water delta and gentle slope palaeogeomorphy, buiided up three-dimensional netty-blanket sand-boy, formed multi and small scale lithostratigraphic trap which was of large-area distribution, made the regularity of " gas generating in the whole basin whole, gas-bearing widely , gas reservoirs controlling by lithology" .
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