CAA: Crystal Size and Fluid Flow in Dolostone Aquifers and Reserviors

CAA：白云岩含水层和储层中的晶体尺寸和流体流动

• 批准号: 9308002
• 负责人: Helene M.C. Danielli
• 金额: $ 5.12万
• 依托单位: Texas Tech University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-06-15 至 1994-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9308002&HistoricalAwards=false
• 关键词: CAA; Crystal; Size; Fluid; Flow

Study of fluid flow through porous rocks is vital to studies of groundwater hydrology and contaminant protection. Previous work has shown that fluid flow is controlled by factors such as porosity, sedimentary grain size, interparticle cement and interstitial mud. Such factors can be measured easily and are widely used in modelling porous media. This project aims to assess the impact of another parameter, CRYSTAL SIZE, on fluid flow in dolostone aquifers. An emerging application of computer-technology, image analysis will be developed and the results shall expand its utility within engineering and geosciences. In addition, the project deals with fundamental questions of the controls of fluid flow in natural materials and the effects that these controls have upon paleohydrology and diagenesis. The results will help satisfy the nation's needs for water and petroleum. In siliclastic rocks, fluids flow between sedimentary particles that are packed together, commonly leaving large, well-connected, interparticle pore spaces. Cements may be precipitated into these pore spaces, but the basic control of the fabric is depositional. In dolostones, fluids flow between crystals that are fitted together in a mosaic; the pore network consists of narrow, sheetlike spaces. Fluid flow in dolostones thus depends on the tortuosity and pore width of the intercrystalline pore system, which are themselves closely related to crystal size. Crystal size is commonly controlled by diagenetic rather than depositional processes. Dolomite aquifers are commonly very finely crystalline, difficult to analyze with a standard dissecting microscope. Image analysis, using core material and a dissecting microscope with slightly enhanced magnification, makes it possible to carry out statistical analyses of crystal size ranges and size distributions. These can be correlated with other textural parameters, and with core analysis data. The project will use around 30 lower San Andres cores in a detailed study of crystal size versus permeability and transmissibility.

流体在多孔岩石中的流动研究对地下水水文学和污染物防护研究具有重要意义。前人的研究表明，流体的流动受孔隙度、沉积粒度、颗粒间胶结物和间隙泥浆等因素的控制。这些因素可以很容易地测量，并广泛用于模拟多孔介质。该项目旨在评估另一个参数晶体尺寸对白云岩含水层流体流动的影响。计算机技术的新兴应用，图像分析将得到发展，其结果将扩大其在工程和地球科学中的用途。此外，该项目还涉及自然物质中流体流动的控制及其对古水文和成岩作用的影响的基本问题。结果将有助于满足国家对水和石油的需求。在硅质岩石中，流体在堆积在一起的沉积颗粒之间流动，通常会留下巨大的、连接良好的颗粒间孔隙空间。胶结物可能会沉淀到这些孔隙空间中，但对织物的基本控制是沉积作用。在白云岩中，流体在镶嵌在一起的晶体之间流动；孔隙网络由狭窄的片状空间组成。因此，白云岩中的流体流动取决于晶间孔隙系统的扭曲度和孔隙宽度，而这两者本身又与晶体大小密切相关。晶体大小通常由成岩作用而不是沉积作用控制。白云岩含水层通常是非常细的结晶，很难用标准解剖显微镜分析。图像分析使用芯材和稍微放大的解剖显微镜，可以对晶体尺寸范围和尺寸分布进行统计分析。这些可以与其他纹理参数和岩心分析数据相关联。该项目将使用约30个下部圣安德烈斯岩心，详细研究晶体尺寸与渗透率和渗透率之间的关系。