辽西低凸起中南段东营组层序地层与隐蔽油气藏预测

Sequence stratigraphy and prediction of the subtle oil traps in the Dongying Formation in the south-central part of the Liaoxi uplift

辽西低凸起中南段油气成藏条件优越,是进一步开展隐蔽油气藏勘探的有利区。针对该区地层、层序方面存在的主要问题,应用层序地层、物源体系以及古地貌等综合分析的方法,构建等时层序地层格架,探讨主要目的层系东二层序、东三层序沉积体系展布规律。分析了层序、构造活动对沉积控制作用,不同体系域沉积体系发育特点及有利砂体展布规律。在此基础上,结合研究区构造面貌与沉积体系展布配置关系,指出研究区有利隐蔽油气藏勘探方向。

The south-central part of the Liaoxi uplift is believed to be the favourable area for the subtle oil traps in the Dongying Formation. The present paper gives a description of the construction of isochronous sequence stratigraphic framework and the distribution of the depositional systems in SQd2 and SQd3 as main target horizons in tetras of sequence stratigraphy, provenance analysis and palaeogeomorphology. Other aspects include the controls of sequences and teetonism on the development of the depositional systems in different system tracts, and distribution of favourable reservoir sandstones. Finally, the potential prostects of favourable subtle oil traps are delineated on the basis of the relationship between tectonic features and distribution of the depositional systems in the study area.