辫状河储层单砂体刻画及剩余油分布

Characterization of single sandbody and remaining oil distribution in braided river reservoir

针对辫状河储层非均质性强和剩余油预测难的问题,以渤海湾盆地L油田馆陶组为例,综合应用野外露头、现代沉积和密井网等资料,对辫状河储层单砂体进行定量刻画,并分析其对剩余油分布的影响。研究表明:研究区辫状河单砂体的平面接触样式分别为砂质接触、半泥质接触和泥质接触。心滩坝宽度250~750 m,长度600~1750 m,辫状河道宽度100~250 m。砂质接触的砂体连通性好,剩余油不富集;半泥质接触和泥质接触的砂体连通性较差或者不连通,在心滩坝单砂体侧翼和辫状河道富集剩余油。该研究为油田中后期剩余油挖潜提供依据。

Because of the strong heterogeneity of braided river reservoirs and difficulty in remaining oil prediction,taking the Guantao Formation in the L Oilfield of the Bohai Bay Basin as an example,data from field outcrop,modern deposition,and dense well patterns etc.were used to characterize quantitatively single sandbodies in braided river reservoirs,and analyze its control effect on remaining oil distribution.The results show that the planar contact patterns of the single sandbody in the braided river of the study area are sandy contact,semi-argillaceous contact,and argillaceous contact,respectively.The width of the central beach bar is from 250 m to 750 m,the length is from 600 m to 1750 m,and the width of the braided channel is from 100 m to 250 m.The sandbodies in sandy contact have good connectivity,and the remaining oil is not enriched.The sandbodies in semi-argillaceous contact and argillaceous contact are poorly connected or disconnected,and the remaining oil is enriched in the flank of the single sandbodies of the braided bar and fluvial river.This study provides a basis for tapping the potential exploitation of remaining oil in the middle and late stages of the oilfield.