河道砂体渗透率分布的分形特征及其应用

The fractal characteristic of the permeability distribution in channel sandbodies and its application to predicting the heterogeneity of the permeability distribution.

河道砂体内部渗透率分布具有很强的非均质性。利用典型密井网区块的资料建立了两种类型河道砂体渗透率分布的原型模型并进行了统计分析，揭示了其渗透率分布的分形特征，求取了表征其渗透率分布的分形特征参数，然后将原型模型抽稀到类似于稀井网情形，利用分形插值方法生成一系列等概率的渗透率分布分形随机场，通过与克里金方法对比及与原型模型的统计指标的对比检验，说明克里金方法在稀井网情况下减弱了渗透率分布的非均质性，然而可利用分形参数及分形方法进行稀井网情况下相同沉积类型河道砂体的渗透率分布预测，表明分形方法在地质条件的控制下能表征河道砂体渗透率分布的非均质性特征。

Shiyou Kantan Yu Kaifa 1999, 26(4), 60 63. The spatial change of the permeability in the channel sandbodies is strongly heterogeneous. In this paper, the permeability cross section prototype models of two types of channel sandbody are built through detailed study for the dense well spacing blocks and the fractal characteristics of the permeability distribution has been revealed by statistics analysis. Then the fractal parameters are calculated from the permeability prototype models through varigram analysis. Through taking some wells away from the prototype model to course it similar to the wide well spacing case, a series of equal probable fractal stochastic realizations and a Kriging field are thus generated. After comparing the statistics indexes of these realizations with that of the prototype model and the Kriging field, it indicates that the Kriging field reduces the heterogeneity of the permeability distribution, whereas the fractal method can be used to predict the heterogeneous permeability distribution of the channel sandbodies in the wide well spacing cases when the depositional environments and the scale are same as the dense well spacing block. We can conclude that the fractal method can be used to characterize the heterogeneous permeability of the channel sandbodies under the control of some geological conditions.