Relationships between the macroscale sedimentology and micromorphology of glacigenic diamictons in south-central British Columbia

This research explores relationships between the macroscale sedimentology and micromorphology of glacigenic diamictons associated with the last Cordilleran Ice Sheet in south-central B.C., and tests the hypothesis that diamictons classified using traditional definitions and sedimentological criteria have unique micromorphologies. Cluster analyses suggest that diamicton types cannot be differentiated by the relative abundances of particular microstructures. Qualitative analyses suggest that microfabrics may be less consistent with macrofabrics in deformation tills and gravity flow diamictons than in undeformed or partially deformed lodgement tills, and evidence of water sorting at the microscale may be more prevalent in gravity flow diamictons than in primary tills. This suggests that though microstructures and microfabrics are not diagnostic to any one diamicton type, depositional processes express themselves at the microscale. Therefore diamicton micromorphology may be used to elaborate on diamicton depositional mechanics and post-depositional modification; however, interpretations are best made within the context of macroscale sedimentological inferences.