水下分流河道带砂体内部构型解剖研究及应用——以鄂尔多斯盆地吴起地区长8段为例

吴起地区长8段为浅水三角洲沉积体系,以三角洲前缘亚相沉积为主,储层主要发育于水下分流河道微相。区内长8段油藏具有储量规模大、储层渗透率低、砂体变化快、油层连续性差、单井产量较低等特征,为实现水平井规模效益开采,在水下分流河道带砂体内储层构型要素特征研究的基础上,应用构型要素电测响应模式,重点开展了水下分流河道带单砂体构型解剖研究,分析了储层构型、砂体展布特征,提出了区内长8段浅水三角洲水下分流河道、单一水下分流河道带和复合水下分流河道带的沉积模式,建立了一套分流河道型浅水三角洲储层构型解剖方法,为研究区水平井部署和水平段轨迹优化调整及预测提供了依据。

Research and application of internal configuration anatomy of sand body in underwater distributary channel zone--by taking Chang 8 reservoir in the Wuqi area of the Ordos basin as an example

The Chang 8 reservoir in Wuqi area is a shallow water delta deposition,mainly composed of delta front sub-facies.The reservoir in this area has the characteristics of large reserves,low permeability,rapid sand body change,poor continuity,etc.,and the single well production is low.In order to realize the largescale development of horizontal wells,it is necessary to carry out detailed single sand body configuration anatomy research.According to the classification standard interface in single sand body configuration,the Chang 8 reservoir is developed in composite underwater distributary channel zone.Combined with the characteristics,the configuration element logging interpretation is carried out by using element electrical logging mode.The reservoir configuration and sand body distribution law are carried out by using configuration analysis method.The depositional models of shallow water delta,single underwater belt and composite underwater distributary channel belt are proposed.A set of anatomical method of distributary channel type shallow water delta reservoir configuration is established,which can optimize horizontal well deployment and horizontal section trajectory.