Abstract:

Raoyang Sag is one of the oil-enriched sags in Bohai Bay Basin. In Raoyang Sag, hydrogen-enriched shale is high-quality source rock, but it has been ignored. Using the successful exploration experience of Nanpu Oilfield for reference, the organic geochemistry features of hydrogen-enriched shale were analyzed. It is indicated that this type of source rocks mainly contributes to the large buried-hill oilfield in Renqiu area. The organic carbon content is over 3%. The pyrolysis hydrocarbon-generation potential is 24.89 mg/g averagely. The type of parent material is type Ⅱ1 with amorphous solid as dominant, and the major source rocks (Es₃) is at the stage of hydrocarbon-generation peak. The newly calculation of resource shows that the oil-generating amount is 28.61×10⁸t and accounts for 27% of total oil-generation amount in the sag. Thus remaining oil resource amount reaches 7.59×10⁸t in Raoyang Sag. The current exploration situation presents an optimistic prospect for oil and gas exploration.

Key words: Bohai Bay Basin, Raoyang Sag, hydrogen-enriched shale, organic geochemistry features, resource amount, high-quality source rocks

摘要：

饶阳凹陷是渤海湾盆地富油凹陷之一,其中发育的富氢页岩是优质烃源岩,但此前一直被忽视,借鉴南堡油田勘探发现的启示,重新对富氢页岩进行了有机地球化学分析。结果表明,该套烃源岩是任丘潜山大油田的主要贡献者:有机碳含量大于3%,热解生烃潜量平均为24.89mg/g;以无定形体占绝对优势的Ⅱ1型母质为主;主力烃源层下第三系沙三段处于生油高峰阶段。资源复算其生油量为28.61×10⁸t,占凹陷总生油量的27%,从而使饶阳凹陷剩余石油地质资源量增加到7.59×10⁸t。就目前资源探明情况,还存在较大的勘探空间和新的勘探领域,勘探前景乐观。

关键词: 渤海湾盆地, 饶阳凹陷, 富氢页岩, 有机地球化学特征, 资源量, 优质烃源岩