A new technique for ice-fabric analysis

Abstract

A new method for ice-fabric analysis which is easily automated is described. The technique relies on a set of digital images of an ice thin section viewed through crossed polarizers and rotated to various angles. From the acquired set of images, the c-axis orientation of all the grains in the image can be determined. The theoretical basis for the technique is described in detail, including corrections for refraction, as well as other corrections for off-axis grains and polarization/reflection effects. An experiment was performed comparing results of the new technique with those of the standard technique. Excellent agreement was obtained. It is expected that an automated system using this technique (currently almost complete) will have a large impact on the amount of information and physical knowledge which can be extracted from ice fabrics in the future.