Sole mark · Base of a bed

Groove casts and tool marks

Long straight ridges or marks on the base of a bed.

How it forms

Objects dragged by a current cut grooves 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.

Flow direction

Gives the flow axis (the line of flow, not which way along it).

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