复合曲流带内部构型界面识别新方法及其应用

New method of recognizing architecture interfaces of complex meander belt deposition and its application

为了刻画海上油田复合曲流带砂体储层结构,分析生产井组平面注水受效不均的地质因素,提出有效增产措施。以渤海Q油田北区NmⅢ2含油砂体为目标砂体,首先基于井间剖面相分析,建立9种单河道间切叠类型,通过正演模拟识别不同切叠类型的地震响应特征;再依据地震响应强度,采用单一振幅属性和双属性融合技术,对地震响应强度的切叠界面进行准确定位;最后结合井间剖面相分析定微相、古地貌特征定走向、单砂体厚度分布及构型定量方法定规模等,完成对复合曲流带内部不同单河道间切叠界面(内部构型界面)的识别与刻画。结果表明:曲流带内部单河道间的切叠界面将片状砂体分割为多个不同的连通体或半连通体,不同的切叠类型渗流能力有所不同。该研究成果能够对复合曲流带砂体注采结构优化提供可靠的地质依据。

In order to propose effective stimulation measures,it is necessary to find a new method to depict the sand reservoir structure of complex meander belt and study the geological factors of uneven efficiency of horizontal water injection in production well group in offshore oilfield.This paper took the oil-bearing sand body NmⅢ2 of Q oilfield in Bohai for example to introduce a new reservoir architecture method.First,nine different cutting relations between every two rivers were concluded by classical meandering stream and the result of micro-facies correlation among the wells.Through combined seismic record obtained from seismic forward modeling,we found that different cutting relations make different seismic wave features.Second,the different intensity of cutting results in the different strength of seismic response.So,we tried to use a single amplitude attribute and dual seismic attribute fusion technology to locate all these different cutting relations accurately.Last,on the basis of the works above,combined with the restoring ancient landscape,the prediction of sand body thickness and configurational formula,precise recognition of architecture interfaces of complex meander belt deposition would be realized.The results show that the meander belt sand bodies were divided into several different connective or semi-connective bodies by the architecture interfaces.It is recognized that the permeability of the different cutting relations is different.The research results can provide reliable geologic accordance for optimizing injection-production structure.