塔里木油田砂岩储层压力敏感系数变化规律研究

VARIATION LAW OF COEFFICIENT OF SENSITIVITY TO PRESSURE IN SANDSTONE RESERVOIR IN TARIM OILFIELD

通过对塔里木油田110块岩样的覆压渗透率试验结果进行回归分析得到岩样的压力敏感系数,根据压力敏感系数与渗透率关系来研究砂岩储层压力敏感系数变化规律。储层压力敏感系数随渗透率的变化而变化,且它们之间成幂函数关系,α=0.053ki-0.3153。储层渗透率愈小,其压力敏感系数愈大,且当储层渗透率小于0.001μm2时,压力敏感系数对渗透率非常敏感。渗透率愈大,储层的压力敏感系数愈小,当储层渗透率大于0.01μm2时,压力敏感系数对渗透率不太敏感,且压力敏感系数小于0.1MPa-1。即低渗储层的渗透率比高渗储层的渗透率对压力变化更为敏感。压力敏感系数是反映渗透率相对变化量的参数。

The coefficients of sensitivity to pressure in sandstone reservoir have been obtained with regression analysis the data on permeability experiments in the condition of overburden pressure by 110 rocks in Tarim oilfield.The variation law of coefficient of sensitivity to pressure in sandstone reservoir has been studied by using the relationship between coefficient of sensitivity to pressure and permeability.The coefficient of sensitivity to pressure is variable with permeability in reservoir.The relationship between coefficient of sensitivity to pressure and permeability is a power function,.The less the permeability in reservoir is,the greater the coefficients of sensitivity to pressure is.When the permeability on reservoir is less than 0.001,the coefficient of sensitivity to pressure is extraordinary sensitivity to permeability.The greater the permeability in reservoir is,the less the coefficients of sensitivity to pressure is.When the permeability on reservoir is more than 0.01,the coefficient of sensitivity to pressure is slight sensitivity to permeability,less than 0.1.That is,the low permeability in reservoir is all the more sensitive to pressure than the high permeability.The coefficient of sensitivity to pressure is the parameter that reflects permeability relative change.