We have just published our latest Earthlearningidea, 'Sand ripple marks in a washbowl' - click here to view this activity in English and Spanish. There is also a short video clip.
Ripple marks in sand can indicate the direction of flow of the water. It is possible to work out the direction of flow of the water that created 'fossil' ripple marks, like the ones shown in the photograph. These are asymmetrical ripple marks in Devonian Old Red Sandstone.
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