相关系数控制的致密油藏裂缝随机表征和生成方法

Correlation coefficients controlled random characterization and generation methods of fractures in tight reservoirs

目前致密油藏天然裂缝的随机表征和生成方法忽略了各个参数之间的相关性,因此得到的随机缝网并不能反映真实情况。本文引入相关系数来定量表征裂缝各参数之间的相关性,同时将裂缝参数服从的每一种随机分布都转化为均匀分布,避免了不同分布下相关系数控制生成的难点。通过半解析的方法建立了分布变换前后相关系数之间的关系,从而给出了相关系数控制下的裂缝各参数的随机生成方法。本文方法可以有效控制裂缝各参数的相关性,得到的裂缝参数更加符合实际情况,为致密油藏裂缝系统的数值模拟和缝网反演提供了基础。

At present,the random characterization and generation methods of natural fractures in tight reservoirs tend to ignore the correlations among fracture parameters,so the obtained random fracture network fails to reflect the real situation.In this paper,the correlation coefficient is introduced to quantitatively characterize the correlation among fracture parameters;at the same time,each random distribution to which fracture parameters are subject is converted into a uniform distribution,hence reducing the difficulty in generating the correlation coefficients control under different distributions.The relationship between correlation coefficients before and after distribution transformation is established by semi-analytical method,and a random generation method of fracture parameters under the control of correlation coefficients is provided.The method introduced in this paper can effectively control the correlation of fracture parameters,so that fracture parameters obtained can reflect the actual situation better,which provides a foundation for numerical simulation and fracture network inversion of fracture systems in tight reservoirs.