Chen S, Kim K H, Qin F, Watson A T
Department of Chemical Engineering, Texas A&M University, College Station 77843.
Magn Reson Imaging. 1992;10(5):815-26. doi: 10.1016/0730-725x(92)90417-x.
Quantitative description of multiphase flow in porous media and local saturation distributions at steady states are of fundamental importance for petroleum recovery. The use of MRI provides an unprecedented means for obtaining such information. In this paper, profile imaging techniques for quantitative evaluation of fluid saturations during flow experiments in porous media are developed. The procedures for overcoming problems arising from very short, fluid saturation-dependent and spatial variation of T2, which are common in porous media, were addressed. The general methods developed should also be applicable to similar inhomogeneous biological systems. Experimental NMR imaging measurements of two-phase displacement were conducted in several limestones and sandstones representing various different types of pore structures, including a macroscopically homogeneous structure, a laminated structure, and a sample that exhibits porosity at different scales. The advantages of using each different type of profile imaging sequence to investigate flow in different types of porous structures are demonstrated. Images showing many features of multiphase flow, including nonuniform flow through different bedding structures, are obtained during the flow experiments. The use of profile images for obtaining many important petrophysical properties, such as permeability, porosity, saturation, and pore structural information, is discussed.
多孔介质中多相流的定量描述以及稳态下的局部饱和度分布对于石油开采至关重要。磁共振成像（MRI）的应用为获取此类信息提供了前所未有的手段。本文开发了用于多孔介质流动实验中流体饱和度定量评估的剖面成像技术。解决了在多孔介质中常见的因T2极短、依赖流体饱和度以及空间变化而产生的问题。所开发的通用方法也应适用于类似的非均匀生物系统。在几种代表不同类型孔隙结构的石灰岩和砂岩中进行了两相驱替的实验核磁共振成像测量，这些孔隙结构包括宏观均匀结构、层状结构以及在不同尺度上表现出孔隙率的样品。展示了使用每种不同类型的剖面成像序列来研究不同类型多孔结构中流动的优势。在流动实验中获得了显示多相流许多特征的图像，包括通过不同层理结构的非均匀流动。讨论了使用剖面图像获取许多重要岩石物理性质的方法，如渗透率、孔隙率、饱和度和孔隙结构信息。
