Fluting (geology)

[1] In geomorphology, a flute is a narrow, shallow channel that runs nearly vertically down the face of a rock surface.

In glaciology, flutes are narrow, elongated, straight, parallel ridges generally consisting of till, but sometimes composed of sand or silt/clay.

Fluted moraines mainly developed in till surfaces on land, but some have been found in shallow glacimarine settings.

[1][2][3] Finally, in glaciology, fluting is used in older publications for smooth, deep, gutterlike channels or furrows cut by glaciers into the stoss side of a rocky hill obstructing its advance.

In sedimentology, a flute is a primary sedimentary structure consisting of a discontinuous scoop-shaped, spatulate, or lingulate depression or groove.

They are typically created by the scouring action of a turbulent, sediment-laden current of water flowing over a muddy bottom.