Sole mark · Base of a bed

Flute casts

Scoop-shaped bulges on the base of a sandstone bed, deep and rounded at one end and tapering at the other.

How it forms

Currents scour scoops into soft mud, which are then filled by the overlying sand.

Typical setting

Sand rapidly deposited on mud, common in turbidites

Way up

They occur on the bottom of beds, bulging downward.

Flow direction

Yes. The rounded, deep end points upcurrent; the tapered end points downcurrent.

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