A simple method to classify diamicts by scanning electron microscope from surface microtextures

Interpretation of quartz sand grain surface microtextures with scanning electron microscopy has been riddled with inconsistencies, invalid assumptions and much subjectivity. Therefore, a novel classification for analysing grain surface microtextures is presented based on the origin of complete grain surfaces. This novel method has solved most of the earlier problems of interpretation of surface microtextures, and it is easy to use and to quickly find evident genetic interpretations of diamicts. The data are plotted graphically in ‘2‐History Diagrams’ or ‘3‐History Diagrams’ for quick visual inspection and statistical evaluation. Source rocks and Quaternary glacial deposits from Scandinavia and Southern Ontario, representing different ice‐substrate dynamics, are analysed to define surface microtextures from typical glacigenic grains, bedrock and fluvially transported grains. Typical glacially crushed grains display large‐scale fractures and abrasion. Shield bedrock grains display large or small‐scale fractures and solution/precipitation microtextures. Fluvially transported grains exhibit abrasion and solution/precipitation microtextures.