渗透率估算可以为石油地质岩心储层渗流能力分析提供数据支撑,为提高石油地质岩心储层的渗流能力,提出了基于X-CT扫描的石油地质岩心储层渗透率估算方法。根据油在两相共渗区的渗透率与水在两相共渗区的渗透率之比,引入Buckley-Leverett方程,计算岩心储层水驱油的分流率,利用X-CT扫描技术,扫描石油地质岩心的分布情况,计算出岩心储层含水饱和度。基于渗透区在井眼与地层之间出现的流体流动现象,计算出岩心储层中泥浆的体积模量和地层的剪切模量,利用斯通利波时差实测值与弹性斯通利波时差之间的差值,计算流体移动指数。根据等效孔隙度与流体移动指数之间的相关性和等效孔隙度与渗透率的相关性,估算出石油地质岩心储层的渗透率。实验结果表明该方法的估算精度可达到90%以上,对估算石油地质岩心储层渗透率具有重要意义。

Permeability estimation can provide data support for the analysis of seepage capacity of petroleum geological core reservoirs. In order to improve the seepage capacity of petroleum geological core reservoirs, a permeability estimation method of petroleum geological core reservoirs based on X-CT scanning technology is proposed. According to the ratio of oil permeability to water permeability in two-phase co-infiltration zone, Buckley-Leverett equation is introduced to calculate the diversion rate of water flooding oil in core reservoir, and the distribution of petroleum geological cores is scanned by X-CT scanning technology to calculate the water saturation of core reservoir. Based on the phenomenon of fluid flow between the borehole and the formation in the permeable zone, the volume modulus of mud in the core reservoir and the shear modulus of the formation are calculated, and the fluid mobility index is calculated by using the difference between the measured stoneley wave time difference and the elastic stoneley wave time difference. According to the correlation between equivalent porosity and fluid mobility index and the correlation between equivalent porosity and permeability, the permeability of petroleum geological core reservoir is estimated. The experimental results show that this method can improve the estimation accuracy to over 90%. It is of great significance for estimating the permeability of petroleum geological core reservoirs.