A form of sedimentation which takes place in lakes marginal to ice-sheets and glaciers. Seasonal fluctuations in particle size and speed of sedimentation take place. During the winter, ice melting is very slow, melt-water streams do not contain much water, and they flow slowly, carrying little material. During the summer, melting accelerates, melt-water streams flow faster and carry more material. In this way, the supply of sediment to the ice-marginal lake varies with the season. Layers called varves, each representing individual years, can be observed in such lacustrine deposits. Varves can be counted, vary in width according to the year, and may be correlated between lakes. In this way, a varve chronology, similar to a treering chronology (see dendrochronology) may be set up. Such chronologies have been built up for Scandinavia and are used to date the retreat of the Weichselian ice-sheet.
The Macmillan dictionary of archaeology, Ruth D. Whitehouse, 1983Copied