大庆油田表外储层渗流特征实验

表外储层渗流特征不同于表内储层。物性特征研究表明,表外储层主要为低渗透和特低渗透储层,分别占33.98%和40.79%。渗流特征研究表明,表外储层具有非达西渗流特征,启动压力的存在会影响注水开发;油水两相渗流时,表外储层的束缚水、残余油的饱和度较高,油水两相渗流的共渗范围较小,驱油效率低,由于黏土质量分数较高,水相相对渗透率上升较慢,曲线形态呈现弓背形状。无因次采油(液)指数变化曲线分析结果表明,表外储层依靠提液增加产量的潜力不大。

EXPERIMENT ON THE SEEPAGE FEATURES FOR THE UNTABULATED RESERVOIRS IN DAQING OILFIELD

Untabulated reservoirs are different from the usable tabulated reservoir in the seepage characteristics.The researches on the physical property features show that the low-permeability and ultra-low-permeability reservoirs are mainly distributed and well-developed in the untabulated reservoirs,which their proportions are 33.98％ and 40.79％ respectively.The seepage characteristic studies show that the untabulated reservoirs possess the features of non-Darcy seepage,and moreover the existed starting pressure can influence the development of the water flooding;when oil and water phases flowing,the saturations of the irreducible water and remained oil are rather higher,the common seepage scope of the two phases is pretty limited,so the oil displaced efficiency is rather lower.And moreover due to the higher mass fractions of the clays,the rising velocity of the water relative permeability is much slower,and the curve morphology takes arched shape.The analyses of the changed curves of the dimensionless oil and liquid production prove that the potentials of enhancing the liquid production and increasing the production are rather limited for the untabulated reservoirs.