27 July 2016
Compare and contrast: pebbles on a beach
Posted by Callan Bentley
Here are two scenes, depicted in two photos each, that I saw on the beach at Machir Bay, Islay, last week. Compare and contrast them.
What stories do these pebbles tell? Answers tomorrow…
Wind erosion (first photo) versus water erosion (second photo) around the pebbles?
That would certainly be my guess. Wind predominantly from right to left in the top photos leaving sand to accumulate in the wind shadows behind the pebbles vs. the lower photos showing the results of water coming in from the left to the right as waves then receding in thinner, less energetic sheet flows from right to left leaving the characteristic dimpled asymmetric flow markings.