These are on the beach at Hunstanton I assume they're volcanic but there appears to be little info on them from a quick Google. I like the patterns they create. This shot has been de-saturated to bring out the details a bit more.
Really interesting. David is the geologist in our family and he reckons they are chalk rocks and much more advanced than stromatolites. Stromatolites don't form in lines like this apparently. He did give a more detailed explanation, but I can't explain it all here. @pusspup