低渗裂缝性油藏渗透率的影响因素研究

Research on factors influencing permeability of low-permeability fracture-type reservoirs

为深入研究低渗透裂缝性油藏的渗流规律，结合某油田某断块岩心进行渗透率的实验研究与分析，得出地层压力、温度及流体性质等参数对低渗透裂缝性油藏渗透率的影响。结果表明，储层随地层压力的升高，裂缝逐渐开启，渗透率先降低后逐渐增大，裂缝开启压力大约在8—10MPa范围内。对实验曲线定量回归拟舍得到渗透率与地层压力的关系式；随着地层温度的升高，各岩心渗透率逐渐降低；同一岩心对地层水的渗透率值要大于对纯净水的渗透率值。实验结果为低渗透储层开发选择合理的地层压力、生产压差等方面提供了理论依据。

In order to probe into the percolation law for the low - permeability fracture - type reservoir, the effect of such parameters as the formation pressure, the temperature, and the fluid property on the permeability of low - permeability fracture - type reservoirs is obtained, based on the experimental study and analysis on the core permeability of a fault block in an oilfield. The result shows that along with the increase of the formation pressure, fractures are gradually unlocked, and the permeability first reduces and then gradually increases, The fracture reopening pressure ranges from eight MPa to ten MPa, The correlation expression of permeability and formation pressure is obtained based on the quantitative fitting and regression of experimental curves. Core permeability gradually decreases as the temperature increases. The permeability of the same rock core to the formation water is higher than that to the pure water. The result can be a good theoretical reference to the selection of rational formation pressure and production pressure difference for the development of low - permeability reservoirs,