低孔低渗型砂岩储层物性特征及油层物性下限值确定——以塔里木盆地塔河西南为例

Research on Low Porosity and Permeability of Sandstone Oil and Gas Reservoir Performance——Take Ta River Southwest of Tarim Basin as the Example

通过对塔里木盆地塔河油田西南部的志留系低孔-低渗型砂岩储层的分析,从砂岩储层的成岩作用、孔隙演化和物性孔隙结构特征等方面进行深入研究,为合理地认识低孔低渗透型储层提供一定的参照和依据。分析认为塔里木盆地塔河油田西南部的志留系低孔-低渗型砂岩储层的油气储集性能易受成岩作用、岩石基本组构的影响,其储层的物性孔隙结构特征有一定的差异,并影响其油层的有效储集性能。结合岩心分析的孔隙度、渗透率与含油岩心饱和度相渗透率的关系,确定油层的物性下限值:孔隙度下限值为6%,渗透率下限低值在1×10-3μm2,高值在10×10-3μm2.

Through a deep study on the low porosity and the low permeability of clasolite reservoir diagenesis and the evolution of blowhole in the reservoir space,the capillary pressure,the feature of blowhole and the cut- off physical property in the low permeability of clasolite reservoir, the oil and gas storage performance is affected easily by the diagenesis and the rocks fundamental fabric of the low porosity and the low permeability of the sandstone reservoir in the Silurian System of the southwestern Ta River in the Tarim Basin. There is certain difference between the porosity structure feature of the reservoir and the reservoir performance. And it may affect the effective reservoir performance. It is determinate that the values of physical properties low limit the reservoir by the relationship between the porosity, the permeability of the core analysis and the saturation, the effective permeability of the oily core. The cut- off value of physical properties in the reservoir：the cut- off value of porosity is 6% ;the cut- off value of permeability is 1×10^-3μm^2 ; the cut - off value of permeability is 10×10^-3μm^2.