裂缝性储集层应力敏感性实验研究

Experimental study on stress sensibility of fractured reservoir.

方法 使用基质渗透率为零的天然致密砂岩和灰岩露头制备裂缝性岩心 ,结合理论推导 ,研究了在不同有效应力条件下渗透率、水力学开度和传导系数的变化规律。目的 评价裂缝性储层的应力敏感性。结果 裂缝的油相渗透率、水力学开度和传导系数随有效应力增大呈非线性函数关系变化。结论 在低有效应力阶段 ,裂缝体现出较强的应力敏感特征 ,当有效应力逐渐增大时 ,其应力敏感性逐渐减弱 ,直至油相渗透率。

Method\ Fractured core prepared from natural dense sandstone (matrix permeability =0) and limestone outcrops, alone with theory deduction, are used to study the change regularities of permeability, hydraulic aperture and conductivity coefficient under different efficient stresses. Purpose\ To evaluate stress sensibility of fractured oil facies permeability. Result\ Oil facies permeability, hydraulic aperture and conductivity coefficient of fracture show non-lineal functional relationship with the increase of effective stress. Conclusion\ Under low efficiency of stress phase, fracture is obviously sensitive to stress. Its sensitivity is gradually reducing along with the development of efficiency of stress till the oil permeability, hydraulic aperture and conductivity coefficient tend to be a constant. \;