High-Resolution X-ray Computed Tomography as a Tool for Visualization and Quantitative Analysis of Igneous Textures in Three Dimensions

Abstract

High-resolution X-ray computed tomography of igneous rocks provides a rapid, non-destructive means to acquire textural data and imagery in three dimensions. Tomographic images are maps of the spatial variations within a specimen of the average linear attenuation coefficient for the input X-ray spectrum, a quantity that depends strongly on mass density and also on atomic number. Visualization of these data benefits from the ability to view sections through the specimen in any location and orientation, and from the ability to extract features of particular interest and display perspective views of them in arbitrary orientation. These images can then be animated to facilitate comprehension of three-dimensional textural relationships. The numerical character of the method also makes these data sets inherently rich in the metrical information required for quantitative characterization and statistical analysis of the sizes, shapes, locations, and interrelations of textural components in igneous rocks.