ripple mark

There was water flowing over it in currents strong enough to leave ripple marks.

The retained pieces are of interest, for on their inner surfaces they are covered with a large number of small patches of very fine ripple marks.

The footprints were found on what was once a river bank, bearing telltale ripple marks and desiccation cracks.

These worm borings, like the ripple marks, show that the sand was once loose.

The rocks show ripple marks which were made by waves when the rock material was soft sand and mud.