河南油田注水地层异常压力理论研究

为了解决河南油田经过常年注水开发,使得地层压力发生变化,加上地层非均质性和复杂断层等方面的影响,地层压力变得更加错综复杂的问题。通过以渗流解析公式和油藏数值模拟两种手段为基础,研究了注水井泄压半径和地层异常压力分布规律,分别建立出注水井泄压半径理论图版。两图版相互验证,虽有一些差异,但趋势和结论均一致。结果表明:当地下注采比大于1时,无因次泄压半径均大于0.5,而且随着无因次波及面积的增大,无因次泄压半径逐渐增大。该图版不仅对河南油田高压区块的现场钻关井方案的合理制定提供了理论依据,对解决其他油田的类似问题也具有指导意义。

Theoretical Study on Abnormal Pressure of Waterflood Formation in Henan Oilfield

In order to solve the problem that formation pressure changes after years of water injection development in henan oilfield, as well as the influence of formation heterogeneity and complex faults, the formation pressure becomes more complicated. Based on the seepage analysis formula and reservoir numerical simulation, the pressure relief radius of injection well and the distribution law of abnormal pressure in formation are studied, and the theoretical chart of pressure relief radius of injection well is established respectively. The two plates have little difference, but they have same trend and conclusion through verifying each other. The results show that the dimensionless pressure relief radius is greater than 0.5 when the underground injection-production ratio is greater than 1, and the dimensionless pressure relief radius gradually increases with the increase of dimensionless swept area. This chart not only provides a theoretical basis for the rational formulation of the field drilling and shut-in scheme in the high-pressure block of Henan oilfield, but also has a guiding significance for solving similar problems in other oilfields.