基于Weibull分布的非均质地层物性参数随机模型

Rand Model of Heterogeneous Formation Physical Parameters Based on Weibull Distribution

地质信息及其表征具有随机不确定性和模糊不确定性,而土体物理力学参数之间又存在着固有的互相关性。通过对地层的已知孔隙率参数进行统计分析,利用Weibull分布模拟孔隙率的空间分布非均质特性,并结合随机中点位移法,模拟非均质地层孔隙结构的空间分布规律,建立了孔隙率的空间分布预测模型。研究建立了地质变量的空间函数关系,结合土性参数之间的相关性,以孔隙率为基本量形成二维地质剖面和三维数字地层,构造面向目标的非均质地层地质模型,探讨了非均质地层物性参数的时空分布特征及其有效描述,对地层局部地质信息的变异和随机性进行精细化描述和预测。

Geological information and characterization are stochastic uncertainty and fuzzy uncertainty, but there is inherent mutual correlation between the physical and mechanical parameters of soil. Based on statistical analysis of the known porosity parameters of stratum, Weibull distribution was adopted to simulate the spatial heterogeneity of porosity, combined with the random midpoint displacement method, then the spatial distribution law of pore structure of non-homogeneous formation was simulated, and the spatial distribution prediction model of porosity was established. The space variate function relation of geological variety was researched and established, and then a 2D geological section and a 3D digital stratum were formed in porosity of the basic amount combined with the correlation between the parameters of soils. The time and space distribution characteristics of heterogeneous stratum physical parameters and its effective description were discussed based on structuring goal-oriented non-homogeneous formation geological model, and the variability and randomness of regional geological information of the stratum were finely described and predicted.