Glacial stress field orientation reconstructedthrough micromorphology and pX-ray computedtomography of till

摘要

Detailed laboratory analyses largely support field studies on the petrology of glacial materials. Inparticular, detailed structural analysis of glacial sediments helps reconstruct the presence, orienta-tion and intensity of glacial stress fields. This pilot study compares thin-section micromorphology(two-dimensional observation under a microscope) and |ìX-ray computed tomography (|ìXR-CT,three-dimensional observation involving data collection and subsequent processing) to evaluate thepotential of the latter technique to yield reliable data. The location and stratigraphy of samplingsites are reported for a complete presentation. Results are encouraging: compared with thin-section micromorphology, pX-ray computed tomography yielded results that are more detailed,reproducible and unaffected by cutting orientation. Moreover, |ìXR-CT is easily applied to inco-herent materials, brittle samples and unique specimens.