冀中坳陷束鹿凹陷潜山多样性油气成藏特征

The hydrocarbon accumulation characteristics of diverse buried hills in the Shulu sag,Jizhong depression

针对冀中坳陷束鹿凹陷潜山油藏特征复杂、主控因素不明等问题,运用石油地质学、沉积学综合研究的方法,对该区潜山油气成藏主控因素和成藏模式进行研究.通过分析潜山类型、潜山储层和潜山油气输导体系的特征,得出了束鹿凹陷具备形成多样性潜山油藏的基础;并从烃源岩条件、储盖组合特点、油藏模式等方面对潜山多样性油气成藏特征进行探讨,明确了各类潜山油藏的成藏主控因素.研究认为,底板层有效性是顶超削截楔状体地层潜山油气成藏主控因素,基底油源断层是洼中隆起潜山油气成藏主控因素,侧向封挡条件是断阶潜山油气成藏主控因素.研究指出斜坡区断阶潜山和断沟侵蚀潜山是下步勘探最为有利的类型和区带,有效地指导了束鹿凹陷潜山目标的落实与钻探部署,实现了潜山领域勘探的新突破.

In view of complex buried-hill reservoir characteristics and unknown controlling factors in the Shulu sag in Jizhong depression,the controlling factors on the buried hill hydrocarbon accumulation and accumulating models were studied using petroleum geology and sedimentary petrology.After analyzing the buried hill types,reservoirs and transport systems,it is concluded that the sag has the foundation for forming diverse buried hill reservoirs.Then the characteristics of diverse accumulation mechanisms were discussed in terms of hydrocarbon source rock,reservoir-cap assemblage and reservoir model.Finally the controlling factors on various buried hill reservoirs were identified.The study shows that the effective floor is the controlling factor on the formation of the top-cut wedge-like buried hill reservoir,the basement oil source fault is the controlling factor on the formation of the buried hill reservoir in the uplifted fault block,and the lateral seal is the controlling factor on the formation of the fault terrace buried hill reservoir.It is proposed that the fault terrace and gully erosion buried hills in the slope area are the most favorable types and zones for future exploration.The study is a useful reference to identification of buried hill targets and well location in the Shulu sag,and helpful to make a new breakthrough to buried hill exploration.