塔河油田底水砂岩油藏水平井剩余油主控因素分析

针对塔河油田一区、九区等强底水砂岩油藏高含水期油水关系复杂、影响因素多、剩余油认识不清造成措施难度大的特点,分析了不同主控因素下水淹模式及剩余油的形成和分布特征。从水平井轨迹与夹层不同的配置关系入手,将轨迹与夹层的配置关系分为全遮挡型、穿行夹层型、穿过夹层型和半遮挡型4种配置关系。根据渗透率组合形态将水平段渗透率组合分为4种形态:两段式、锯齿式、台阶式和均匀式,并结合油井生产动态研究了不同配置关系及渗透率形态所对应的水平段水淹模式,描述其对剩余油不同控制作用,并结合矿场试验给出各种剩余油赋存方式适合的挖潜手段,为底水油藏剩余油精细挖潜提供依据。

Main controlling factors for remaining oils in horizontal wells in sandstone reservoirs with bottom water in the Tahe Oil Field

In blocks no.1 and 9 in the Tahe Oil Field, complicated oil/water relationship and various controlling factors have made it difficult to tap remaining oils in sandstone reservoirs with bottom water during high water cut period. Water flooding pattern and remaining oil occurrence were analyzed in view of different controlling factors. Horizontal tracks and interlayers have four different configurations:totally blocking, horizontal to interlayers, crossing interlayers, and half blocking. The permeability of horizontal layers can be divided to four styles:two stage type, serration type, step type, and homogeneous type. Combining with production performance, we studied water flooding mode in horizontal section corresponding to different configurations and permeability styles, and discussed its control on remaining oil. Some methods for tapping remaining oil in reservoirs with bottom water were proposed.