曲流河点坝地下储层构型精细解剖方法

以胜利油区孤岛油田11J11密井网区为例,应用岩心、测井,动态等资料,对前人关于河流相野外露头和现代沉积的原型模型研究成果进行了分析,提出了一套点坝识别及精细解剖点坝内部构型的方法,确定了地下点坝的识别标志。根据嫩江月亮泡曲流河段的卫星照片资料,推算了点坝长度与河流满岸宽度的关系式,并将其用于识别研究区点坝。总结了点坝内部泥质侧积层的三类分布模式,应用经验公式、水平井及小井距资料确定了侧积体和侧积层的规模及产状,进而根据侧积层模式、规模及产状进行了研究区点坝内部构型解剖,用检查井动态资料进一步验证了解剖结果,最终建立了研究区真正意义上的三维储层构型模型及参数模型,并进行了油藏数值模拟。数值模拟结果显示,剩余油主要富集在点坝中上部。该方法在研究区取得了明显的效果,可用于类似油田储层精细研究及剩余油分布预测。

An accurate method for anatomizing architecture of subsurface reservoir in point bar of meandering river

Taking 11J11 dense spacing area of Gudao Oilfield in Shengli oil area as a case, the data of coring,logging and performance of wells were used to analyze the former results about outcrop and modern deposition of meandering river. A comprehensive analysis method for reservoir architecture of point bar was proposed. The recognition mark of point bar in the studied area was determined. According to the satellite pictures of meandering river of Yueliangpao in Nenjiang River, the relational expression of the length of point bar and the width of bankful channel was derived. The three distribution patterns of lateral accretion shale beddings were summarized. The empirical formula, data of horizontal wells and dense spacing wells were used to ascertain the scale and occurrence of lateral accretion sandbody. The architecture of the point bar reservoir in the studied area was anatomized. The research results are in good accordance with the performance data of ascertained well. The models of three-dimensional reservoir architecture and reservoir parameters were set up. The numerical simulation of reservoir shows that the remaining oil was distributed in the middle-upper point bar. This method was successfully applied in Gudao Oilfield and could be used in other similar oilfields.