断陷盆地陡坡带构造样式与油气聚集—以渤海湾盆地辽河坳陷西部凹陷陡坡带为例

Structural style and hydrocarbon accumulation in the steep slope zone of faulted basin—an example from the western sag of the Liaohe Depression,the Bohai Bay Basin

慕德梁 孟卫工 李成 李晓光 柳锦云 王占忠

Mu Deliang Meng Weigong Li Cheng Li Xiaoguang Liu Jinyun Wang Zhanzhong

通过对渤海湾盆地辽河西部凹陷东部陡坡带构造演化史、陡坡带沉降史和断裂活动强度等构造地质方面的研究,把陡坡带划分为3种构造样式:①正反转构造样式;②伸展断裂构造样式;③"潜山"披覆构造样式。对研究区的演化史进行研究,分为正反转演化类型和伸展构造演化类型。由陡坡带沉降史研究得出,本区构造沉降次序是"由北向南"逐渐沉降演化的。对断裂生长指数的定量计算表明,台安-大洼断裂的不同部位活动强度不同,大洼地区断裂活动强度最大。在该区部署的赵古1井在太古界潜山获得高产油气流。对陡坡带断裂演化史的研究进而分析裂缝发育带是在潜山深部寻找高产油气藏的关键。

Study of structural evolution,subsidence history,and fault activity intensity of the eastern steep slope zone of the western sag in the Liaohe Depression of the Bohai Bay Basin reveals three structural styles:1)positive inverse structure,2)extensional fault structure,and 3)buried-hill drape structure.The evolution history of the study area can also be divided into two types:the positive inverse evolution and extensional structural evolution.Study of subsidence history indicates a gradual subsidence from north to south.Quantitative calculation of the fault growth index shows various fault activity intensities in different parts of Taian-Dawa area with the strongest intensity in Dawa.The Well Zhaogu-1 in Dawa tested high oil and gas flows from the Archeaozoic buried-hill.It is therefore suggested that a study of fault evolvement and a further analysis of fracture distribution are the key to oil and gas discoveries in deep of buried-hill and provide clues to the exploration of buried-hill reservoirs near hydrocarbon kitchen in steep slope zones.

10.11743/ogg20090514