渤海湾盆地莱州湾凹陷沙河街组第三、第四段烃源岩有机相特征

研究渤海湾盆地莱州湾凹陷沙河街组第三、第四段烃源岩的发育特征。基于烃源岩地球化学数据,划分了烃源岩有机相,建立了有机相与沉积相的对应关系,进而预测有机相的平面展布。研究结果表明,莱州湾凹陷沙河街组第三、第四段有机相与沉积相对应关系较好,其中深湖-半深湖相对应AB、B型有机相,滨浅湖相对应B、BC型有机相,辫状河三角洲和扇三角洲对应C型有机相,且沉积相与有机相对应关系在同一亚段内相同。优质烃源岩主要分布于莱州湾凹陷北部与东部的深湖-半深湖相中。

Organic facies characteristics of source rocks on the 3rd and 4th member of Shahejie Formation in the southern Laizhouwan Depression,Bohai Bay Basin,China

The development characteristics of source rocks in the third and fourth member of Shahejie Formation in Laizhouwan sag,Bohai Bay Basin are studied.Based on the geochemical data of source rocks,the organic facies of source rocks are classified,the corresponding relationship between organic facies and sedimentary facies is established,and the planar distribution of organic facies is predicted.Research results show that the organic facies of Shahejie Formation in the southern Laizhouwan has a good corresponding relationship with sedimentation facies,among which the deep lake and semi-deep lake facies corresponds to the AB and B type organic facies,the shore-shallow lake corresponds to the B and BC type organic facies,the braided river delta and fan delta facies correspond to the C type organic facies.The corresponding relationship also occurs in the same sub section.High quality source rocks with good organic facies are mainly distributed in the deep lake and semi-deep lake facies in the northern and eastern Laizhouwan Depression.