辽东湾坳陷辽西低凸起潜山构造特征与油气聚集

Structural characteristics and hydrocarbon accumulation in the buried hills of the Liaoxi low salient,the Liaodong Bay Depression

辽东湾坳陷辽西低凸起具有明确的南、中、北3段构造分段特征,潜山构造样式呈典型的翘倾断块状态,潜山地层结构由太古界变质岩、寒武-奥陶系碳酸盐岩和中生界火山岩构成3层复式结构。辽西低凸起潜山油气聚集主要与两个因素相关:一是古近系是否发育储层,二是辽中凹陷油气资源是否充足。因此,大规模的潜山油气聚集多是在主断槽油气供应充分、且潜山上覆古近系缺乏优质储层的情况下发生的。

The Liaoxi low salient in Bohai presents clear structural segmentation characteristics and can be divided into southern, middle, and northern parts. The buried hills there present a typical structural style of tilting fault-block and a three-layer architecture consisting of the Archaean metamorphic rocks, Camhrian-Ordovician carbonates, and Mesozoic volcanic rocks. Hydrocarbon accumulations in the buried hills of Liaoxi low-salient are mainly determined by two factors：development of reservoirs in the Paleogene and abundance of hydrocarbon resources in the Liaozhong sag. Therefore, large-scale hydrocarbon accumulations in buried hills occur mostly in circumstances that hydrocarbon supply from the main fault-troughs is plentiful and high-quality reservoirs are absent in the Paleogene.