Collaborative Research: Solute Transport in Multimodal, Heterogeneous Geological Formations Combining Sedimentologic and Engineering Approaches

合作研究：结合沉积学和工程方法的多模式、非均质地质构造中的溶质运移

• 批准号: 0001125
• 负责人: Robert Ritzi
• 金额: $ 19.05万
• 依托单位: Wright State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0001125&HistoricalAwards=false
• 关键词: Collaborative; Research; Solute; Transport; Multimodal

0001125Ritzi We will develop a hierarchical spatial random function (HSRF) model that represents permeability, sedimentary structures, and sedimentary units defined by bounding surfaces in granular aquifer systems. At the smallest scale, facies are defined as regions of unimodal permeability and, if present, of cross-strata sets with common orientation to the laminae. Facies will be represented by a continuous random variable having anisotropic correlation controlled by bedding and/or the orientation of cross-strata sets. Assemblages of facies, such as the combination of facies filling a single channel, will be represented by an indicator random variable and associated transition probabilities which represent the proportions, geometries, and juxtapositioning of each facies. A complex of facies assemblages, such as juxtaposed channel fill, bar accretion, and overbank assemblages within channel belt deposits, is represented by a higher-tier indicator random variable with transition probabilities representing the proportions, geometries, and juxtapositioning of the assemblages. The continuous and indicator variables of all three levels will be mathematically expressed in a single HSRF model suitable for integration with analytical expressions for solute spreading. The HSRF model departs from current models and approaches in that it can capture complex, non-Gaussian spatial distributions and can incorporate interpretive sedimentology to constrain the geostatistical models. In combined field studies and model temperament, we seek to address the following questions relating to (1) the distribution of permeability in granular media and (2) solute spreading. (1) Questions relating to distribution of permeability: o Does the HSRF model, with its three hierarchical levels, capture the aspects of permeability and sedimentary structure important for understanding solute spreading at the scale of typical plumes? o Are the attributes of any one hierarchical level correlated with those of another level? o Can the HSRF model be used to improve the conditional estimation of permeability at unknown locations? o Can the HSRF model be used as a framework for incorporating geological/sedimentological soft data as geostatisticl models are developed? (2) Questions related to solute spreading: o What are the relative contributions of the three hierarchical levels to both longitudinal and lateral solute spreading? o As the univariate statististics and the spatial correlation of permeability become increasingly different across facies boundaries, at what point are the moments of solute spreading significantly affected? o Under what conditions can representation of any of the hierarchical levels be ignored? o Under what conditions can transport in a multimodal heterogeneity be modeled with effective, plume-scale-dependent parameters? To answer these questions, we are conducting a collaborative, interdisciplinary project involving investigators at both the University of California, Berkeley, and Wright State University. As in past URI-funded projects at Wright State University, the project will provide research experiences for undergraduates.

0001125RITZI我们将开发一个层次的空间随机函数（HSRF）模型，该模型代表渗透性，沉积结构和沉积单元，通过在颗粒含水层中定义的表面定义。 在最小的规模上，将相位定义为单峰渗透率的区域，如果存在，则具有跨层的跨层套装，其方向与薄片具有共同的方向。 相对于由床上用品和/或跨层集的方向控制的连续随机变量将以各向异性相关性来表示。 相的组合（例如填充单个通道的相的相结合）将由指标随机变量和相关的过渡概率表示，这些变量代表每个相的比例，几何形状和并置。 一系列的组合组合，例如并并列通道填充，杆积聚和通道皮带沉积中的超银行组合，由高层指示器随机变量表示，其过渡概率代表了组合的比例，几何形状和并置。 所有三个级别的连续和指示变量将以数学表达在单个HSRF模型中，适合与分析表达式集成以进行溶质扩散。 HSRF模型偏离了当前的模型和方法，因为它可以捕获复杂的非高斯空间分布，并且可以结合解释性沉积学以限制地统计模型。在联合现场研究和模型气质中，我们试图解决与（1）颗粒介质中渗透率分布和（2）溶质扩散有关的以下问题。 （1）与渗透率分布有关的问题：o HSRF模型具有三个层次级别，捕获了渗透性和沉积结构的各个方面，对于理解溶质在典型羽流的规模上很重要吗？ o任何一个层次级别的属性是否与另一个级别的属性相关？ o可以使用HSRF模型来改善未知位置渗透率的条件估计？ o可以将HSRF模型用作将地质/沉积学软数据纳入GeoStatisticl模型的框架？ （2）与溶质扩散有关的问题：o三个层次级别对纵向和横向溶质扩散的相对贡献是什么？ o随着单变量的统计学和渗透率的空间相关性在各个相边界之间变得越来越不同，在什么时候溶质散布的时刻会显着影响？ o在什么条件下可以忽略任何层次级别的表示？ o在多模式异质性中可以通过有效的羽尺度依赖性参数建模在哪些条件下？ 为了回答这些问题，我们正在进行一个合作的跨学科项目，涉及加利福尼亚大学，伯克利分校和赖特州立大学的研究人员。 就像赖特州立大学过去由URI资助的项目一样，该项目将为本科生提供研究经验。