Black sand patterns

Black sand patterns at Piha.

Something to do with when the waves come in, the black sand is heavier and settles first, then when the waves pull back out, they pull the slightly lighter sand off the top. Hmmm saying if out loud that doesn't make much sense. Errrr. Some geological phenomenon makes these patterns appear. It may or may not be to do with the weight of the sand...

Anyhow, they are beautiful. I upped the contrast of this slightly but not too much.

12kms of hiking in the Waitakere Ranges then walking along the edge of the Tasman Sea was a splendid way to spend my last Thursday in New Zealand