东营凹陷沙河街组烃源岩结构对排烃成藏的控制作用

东营凹陷主力烃源岩沙四段上亚段及沙三段下亚段具有多种岩性结构形式,为考察不同岩性结构的烃源岩排烃作用及成藏特征,对其地质地球化学特征进行了研究。通过对钻井取心物理特征的观察及不同结构烃源岩地质地球化学特征的比较,认为沙四段上亚段及沙三段下亚段下部主要发育纹层状泥页岩,油气以远距离侧向运移为主;沙三段下亚段上部及沙三段中亚段主要发育块状泥岩,油气以垂向运移为主,存在透镜体充注式排烃、顶部泥岩向下伏砂岩排烃及底部泥岩向上覆砂岩排烃三种方式。东营凹陷不同结构的烃源岩的排烃方武造成了油气分布的差异,沙四型原油分布于凹陷外围,沙三型原油分布于凹陷内围,混合型原油分布于中间地带。

The control of source rock structure on hydrocarbon expulsion and reservoir forming of Shahejie formation in Dongying Sag

There were many types of lithologic structures in upper member 4 and lower member 3 of the Shahejie forma-tion which were the main source rocks in Dongying Sag. The geologic and geochemical characteristics of the source rocks with various lithologic structures were researched to know the hydrocarbon expulsion and res-ervoir forming characteristic.Through the observation of physical property of drilled coring and comparison a-mong geologic and geochemical characteristics for source rocks with various structures, laminated mud-stone developed and long-distance lateral oil-gas migration occurred mainly in upper Es4 and lower part of lower Es3;massive mudstones developed and vertical oil-gas migration occurred mainly in the upper part of lower Es3 and middle Es3,there were three hydrocarbon expulsion ways of lens filling,from top mudstone to un-derlying sandstone and from bottom mudstone to overly-ing sandstone.The diversity of hydrocarbon expulsion in different source rocks controlled the oil-gas distri-bution in Dongying Sag.The oil from Es4 distributed a-long periphery of the sag,the oil from Es3 distributed at the inner side of the sag,and mixed oil distributed be-tween them.