RUI: Predicting Transport Through Heterogeneous Facies Assemblages: Geostatistical Anatomy of Buried-Valley Aquifers III

RUI：通过非均质相组合预测输运：埋谷含水层 III 的地统计解剖

• 批准号: 9903067
• 负责人: Robert Ritzi
• 金额: $ 11.2万
• 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: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9903067&HistoricalAwards=false
• 关键词: RUI; Predicting; Transport; Through; Heterogeneous

9903067RitziThese research tests the hypothesis that similarities exist in the physical heterogeneity among granular aquifers formed by similar depositional environments. The physical heterogeneity of aquifers can be represented within a three-dimensional geostatistical model that represents both its structured and random aspects. Because the subsurface at environmental sites is never exhaustively characterized, decisions must be made under uncertainty and risk-qualified models are needed. Useful statistical models of aquifer heterogeneity will only come from many well-studied examples at data-rich sites, in a variety of depositional environments. Our long-term research goal is to develop statistical models for the most relevant features of the heterogeneity in granular aquifer systems in specific depositional setting and to evaluate the level of detail necessary in simulating macrodispersive transport. We have begun by looking at glacigenic buried-valley aquifers in the North American mid-continent. These have heterogeneity ranging across several scales, from unimodal distributions of permeability within facies, to weakly multimodal distributions of permeability within architectural elements, to strongly multimodal heterogeneity at the scale of facies assemblages. The objective of the project are to build data bases and compute facies proportions, variance in proportion with translation, mean length, variance in length, coefficient of embeddedness and transition probability. Furthermore, we compute the geometric mean, variance, and correlation range of permeability within facies. We refer to these statistics collectively, when related to features of the depositional environment, as a quantitative facies model. We will compare quantitative facies models developed for four different buried-valley aquifers occurring across a broad region of the mid-continent. Flow and transport modeling will be used to assess whether or not observed differences are relevant in environmental decision making. This is an RUI proposal, and as in prior phases of funding, the project will have significant undergraduate involvement.

9903067Ritzi这些研究检验了这样的假设，即由相似的沉积环境形成的颗粒状含水层的物理非均质性存在相似性。含水层的物理非均质性可以用三维地质统计模型来表示，该模型既代表了含水层的结构方面，也代表了其随机方面。因为环境场地的地下永远不会被详尽地描述，所以必须在不确定的情况下做出决定，并且需要风险合格的模型。有用的含水层非均质性统计模型只能来自各种沉积环境中数据丰富的地点的许多经过充分研究的例子。我们的长期研究目标是开发特定沉积环境下颗粒含水层系统中最相关的非均质性特征的统计模型，并评估模拟宏观弥散运移所需的详细程度。我们首先从北美中部大陆的冰川潜谷含水层开始。它们具有多个尺度上的非均质性，从相内渗透率的单峰分布，到建筑单元内渗透率的弱多峰分布，再到相组合尺度上的强多峰非均质性。该项目的目标是建立数据库并计算相比例、与平移成比例的方差、平均长度、长度方差、嵌入系数和转换概率。此外，我们还计算了相内渗透率的几何均值、方差和相关范围。当与沉积环境的特征相关时，我们将这些统计统称为定量相模型。我们将比较中大陆广大地区四个不同潜谷含水层的定量相模型。将使用流动和传输模型来评估观察到的差异是否与环境决策相关。这是瑞安的一项建议，与之前的资助阶段一样，该项目将有大量的本科生参与。