In
sedimentology, winnowing is the natural removal of fine material from a coarser
sediment by wind or flowing water. Once a sediment has been deposited, subsequent changes in the speed or direction of wind or water flowing over it can agitate the grains in the sediment and allow the preferential removal of the finer grains. This action can improve the
sorting and increase the mean
grain size of a sediment after it has been deposited.
[Compton, R. R., 1962, Manual of field geology, John Wiley & Sons, 378 p. ]
The term ''winnowing'' is from
the analogous process for the agricultural separation of wheat from chaff.
References
External links
{{Wiktionary-inline, winnowing
Sedimentology
Separation processes