长垣油田辫状河砂体储层内部构型研究

STUDIES ON THE INTERNAL CONFIGURATIONS OF BRAIDED-RIVER SANDBODY RESERVOIRS OF PLACANTICLINE OILFIELDS

针对大庆长垣特高含水后期密井网条件下辫状河砂体，应用现代沉积、野外露头、岩心、测井和动态生产资料，采用“模式预测，分级控制”的内部构型研究方法，由沉积单元、辫流带、辫状河道和心滩坝、心滩坝内部构型4个层次分级描述，精细研究辫状河砂体内部构型，首次确定长垣辫状河砂体：为“浅的砂质辫状河”，并建立了辫状河砂体构型要素定量分布模式。采用序贯指示模拟与人机结合再处理的方法建立了精密网格三维储层构型模型，实现了辫状河河砂体内部构型三维定量表征。研究表明，长垣辫状河为浅的砂质辫状河三期叠加沉积，西部发育大规模下切带，辫状河内部心滩坝宽约400m，辫状河道宽约80m，心滩坝内部夹层呈窄条带状随机分布。

In views of the braided-river sandbodies under the conditions of the dense well pattern in the late period of extra-high water cut of Daqing Placanticline, with the help of the data of modern sedimentation, field outcrop, cores, well logging and production performances, four-graded hierarchy characterizations i. e. Sedimentary unit, flown belts of the braided rivers, braid-shaped channel ＆ mid-channel bar and internal configuration of the bar are conducted by the studying method of the internal configuration - j＇ Model prediction and graded control, the internal configurations of the braided-river sandbodies are detailed studied： at first, ＂shallow sandy braided rivers＂ are determined for the sandbodies of the braided rivers in the Placanticline, and then the quantitative distribution models of the factors of the internal configurations of the above sandbodies are established. By adopting the re-processing method of sequential instruction modeling and manomputer interaction, the model of 3I） reservoir configuration with high-resolution grid is built, so the 3 D quantitative characterizations of the internal configurations of the brai-ded-river sandbodies are realized. The researches show, that the braided rivers in the Placanticline belong to No. 3 period stacked deposition of shallow sandy braided rivers, large-size downcut belts in the western part are well-de- veloped, the width of the mid-channel bars in the internal parts of the braided rivers is about 400m, the channel of the rivers is 80m wide or so, narrow and belt-like internal interbeds are distributed at random in the bars.