The development of layered sediment beds in the laboratory as an illustration of possible field processes

Abstract

Abstract Sediments laid down under water are frequently layered, the layers being identified by changes in particle size and/or density. The paper considers an example of such layering examined in a core from the Nares Abyssal Plain using an accurate, non-destructive X-ray technique for measuring density. It also reports a series of laboratory experiments in which a sediment containing sand, silt and clay-sized particles was introduced at a variable deposition rate into settling columns. The development of the bed was monitored using the same X-ray technique for density measurement, and the occurrence of layers, marked by changes in density and particle size distribution, is noted and discussed. It is suggested that a genuinely uniform naturally occurring sediment may well be quite uncommon.