SCANNING ELECTRON-MICROSCOPY IN ANALYSIS OF GLACIAL ABRASION OF QUARTZITIC SUBSTRATA

The paper presents the first results of a S.E.M. analysis of glacial a brasion micromarks on quartzitic bedrock. The examined samples are fra gments of polished flagstones directly collected on for-er glacial bed s, from the Highlands of Scotland in an area where devensian glacial f eatures are remarkably well preserved. Their S.E.M. examination allows to define three main surface types from complicated initial microtopo graphies. It also allows to distinguish typical microforms produced by attrition or striation below temperate glaciers and to determine the frequency of these microforms at different scales. Some comparisons ar e made with abrasion features observed in the field with microforms kn own on morainic quartz grains and with figures which occur on fault pl anes.