flute mark A tongue-shaped scour cut into mud by a turbulent flow of water. The tongue is deepest at the up-current end and the flute can thus be used as a palaeocurrent indicator. If the flute is infilled by sediment a flute cast will be preserved in the base of the overlying bed. Although once believed to be diagnostic of turbidite deposition, flutes can form in any setting where water flows strongly over soft mud.

flute mark A tongue-shaped scour cut into mud by a turbulent flow of water. The tongue is deepest at the up-current end and the flute can thus be used in a palaeocurrent analysis. If the flute is infilled by sediment a flute cast will be preserved in the base of the overlying bed. Although once believed to be diagnostic of turbidite deposition, flutes can form in any setting where water flows strongly over soft mud.