基于启动压力梯度的低渗透砂岩储层分类研究

Study on Classification of Low-Permealility Sandstone Reservoirs Based on the Starting Pressure Gradient

利用大庆杏树岗油田的取芯资料,论述了低渗透储层的岩性、物性、含油性以及渗流特征。通过测试不同渗透率岩芯样品的启动压力梯度,得出了启动压力梯度与渗透率之间具有明显的相关性,不同渗透率储层的启动压力梯度变化率的数量级不同,并依此建立了低渗透砂岩储层分类的新方法。按照该方法重新确定了低渗透储层的渗透率上限,并将低渗透储层划分为3种类型。

This paper studies the lithology, physical properties, oil-beating and seeping characteristics of lowpermeability reservoirs by using the core data from Daqing Xingshugang oilfield. Based on the starting pressure gradients measured from the cores with different permeabilities, there exists a good correlation between starting pressure gradients and permeabilities. The order of magnitude of the changing rate of different reservoir starting pressure gradients is different. Thus, a new classification method of low-permeability reservoirs is set up. Using this new classification method, the upper limit of low-permeability reservoirs is redefined and the low-permeability reservoirs are classified into three types.