摘要
经过50多年的勘探开发,乌尔逊—贝尔凹陷己进入高勘探阶段,寻找大规模构造油气藏越来越难,赋存在斜坡区的构造—岩性油气藏逐渐成为勘探的重点。本次研究在凹陷整体研究解剖的基础上,探讨了大型斜坡区的地质分异特征,根据斜坡产状、构造活动强度、供源强度、同沉积断裂组合样式将乌尔逊—贝尔凹陷斜坡区划分为6种类型,分别为:强供源高坡度顺向断阶型、强供源中坡度复合断阶型、强供源中坡度反向断阶型、弱供源低坡度顺向断阶型、弱供源低坡度反向断阶型和弱供源中坡度顺向断阶型,不同类型的斜坡具有不同的控砂机制和成藏特征。物源供应强度和斜坡倾角控制着沉积体系的发育类型,同沉积断裂与沟谷的组合方式控制着沉积体系的展布特征;断裂—砂体—烃源岩的时空配置决定着主要发育的油藏类型。经勘探实践,在乌尔逊—贝尔凹陷贝西南、乌东南和乌北斜坡均获重大发现,证实了斜坡区是陆相断陷湖盆内油气预探与规模增储的主要突破方向。
After more than 50 years of exploration and development,Wuerxun-Beier Sag has entered a high exploration stage.It is more and more difficult to find large-scale structural hydrocarbon reservoirs.Structural-lithologic hydrocarbon reservoirs in the slope areas have gradually become the focus of the exploration.Based on the overall study and dissection of the sag,the geological differentiation characteristics of the large-scale slope area were discussed,according to the occurrences of the slope,the intensity of the tectonic activities,the intensity of the source supply and the patterns of the syn-sedimentary fault combination,the slope zone Wuerxun-Beier Sag can be divided into six types,namely,the downward fault-step type on the steep slope with strong supply source,the compound fault-step type on the middle slope with strong supply source,the reverse fault-step type on the gentle slope with strong supply source,the downward fault-step type on the gentle slop with weak supply type,the reverse fault-step type on the gentle slope with weak supply source and the downward fault-step type on the gentle slope with weak supply source.Different types of the slope have different sand controlled mechanisms and reservoir accumulating characteristics.The source supply intensity and the slope dip control the developed types of the sedimentary system,the combinations between the syn-sedimentary faults and the valleys control the distribution characteristics of the sedimentary system;the spatial and temporal distributions among the faults,sandbodies and source rocks determine the main developed hydrocarbon reservoir types.Through the exploration practice,the significant discoveries have been made on Southwest Beier Sag,Southeast and North Slopes of Wuerxun,which have confirmed that the slope area is the main breakthrough direction for oil and gas exploration and large-scale reservoir increase in the continental faulted lake basin.
作者
蒙启安
吴海波
李军辉
刘赫
李跃
邹越
MENG Qi’an;WU Haibo;LI Junhui;LIU He;LI Yue;ZOU Yue(Exploration and Development Research Institute of Daqing Oilfield Co Ltd,Daqing 163712,China)
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2019年第5期59-68,共10页
Petroleum Geology & Oilfield Development in Daqing
基金
国家科技重大专项“大庆油气持续有效发展关键技术研究与应用”(2016E-0202)
