基于分形方法的多孔介质有效应力模型研究

在充分分析国内外多孔介质有效应力研究基础上，针对石油工程中深层岩石复杂结构特征，应用分形几何理论,分别建立了深层多孔介质岩石有效应力的二维和三维分形计算模型。该模型能反应任意孔隙结构下的应力作用关系，是现有相关有效应力模型的补充和完善。为了现场应用方便，进一步给出多孔介质有效应力分形模型的简化式。实例计算表明，应用简化式计算的有效应力值误差在7％以内，可以满足油田现场的要求，并且应用简化式有利于应用测井数据获得连续的有效应力剖面。

Research on effective stress model in porous media based on fractal method

On the basis of the full study on the chinese and foreign information about the effective stress in porous media, the 2D and 3D fractal calculation models for the effective stress in deep porous media are respectively established by using fractal geometry theory. It considers the rock characteristics of the deep complex structure in petroleum engineering. The models can show the stress relationship in any pore structure rock and are the improvement to the existing model about the effective stress. In order to facilitate the on-site applications, the simplified models are further given for the effective stress fractal models in porous media. The examples of calculation shows that the culation errors for the simplified models are less than 7% and can meet the requirements of on-site oil field.An effective stress profile can be obtained by applying the simplified models to the logging data.