Assessing Textural Variation in Laminated Sands Using Digital Image Analysis of Thin Sections
Assessing Textural Variation in Laminated Sands Using Digital Image Analysis of Thin Sections
复制标题
使用薄片数字图像分析评估层状砂的结构变化
DOI：
10.1306/061502730133
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发表时间：
2003
影响因子：
2
通讯作者：
W. Schlager
中科院分区：
文献类型：
--
作者：
E. Berg;V. Bense;W. Schlager
虽然在过去已经研究了沉积物中的纹层间参数变化，但测量的参数通常限于粒度分布和总孔隙度。层状沉积物物理性质的大小和方向特征还取决于颗粒的形状和方向、堆积、孔径特征和孔隙网络的性质。在物理特性模型中遗漏颗粒沉积物的完整特性可能会导致模型值和测量值之间的系统性不匹配。然而，这些空间变量参数的高分辨率量化工具并不容易获得。为了提供这样一个工具，图像分析程序的基础上薄切片的数字图像。该程序定义了一系列矩形测量窗口，其长边平行于分层，并测量每个窗口的沉积物特性。因此，创建了垂直于分层定向的参数值的集合。经过验证的图像分析程序，使用比较实验室测量，该程序被应用到两个薄切片图像的未固结细粒，层积砂。在颗粒和孔隙特征的日志中观察到的定量变化与在原始图像上观察到的层理很好地相关。总的来说，图像分析程序被证明是一个有用的和通用的工具，用于量化的纹理特征的变化，在子层尺度。
Although between-laminae parameter variations in sediments have been studied in the past, measured parameters were generally limited to grain-size distribution and total porosity. The magnitude and directional characteristics of physical properties of laminated sediments also depend on the shape and orientation of particles, packing, pore-size characteristics, and properties of the pore network. Leaving out a complete characterization of granular sediment in models of physical properties could result in a systematic mismatch between modeled and measured values. However, tools for high-resolution quantification of these spatial variable parameters are not readily available. In order to provide such a tool, an image-analysis procedure is presented based on digital images of thin sections. The procedure defines a sequence of rectangular measurement windows, with their long sides oriented parallel to stratification, and measures the sediment characteristics for each window. Logs of parameters values, oriented perpendicular to stratification, are thus created. After verification of the image-analysis procedure using comparative laboratory measurements, the procedure is applied to two thin-section images of unconsolidated fine-grained, laminated sands. The quantitative variations observed in the logs of grain and pore characteristics correlate well with bedding observed on the original images. Overall, the image-analysis procedure proved to be a useful and versatile tool for quantifying variations of textural characteristics on sub-lamina scale.