Continuing the theme of patterns that decorate the rocks at Kimmeridge Bay, the circular and ovoid fractures seen here in large detached boulders on the shore made me think of noughts and crosses. They obviously result from some entirely different processes to those that produce the large and small polygons in the rock ledges.
There are fossil ammonites in these boulders as well as the fracture patterns.
Cross or star shape at the junction of several fissures in the rock layer above. And below some slightly different sub-circular fracture patterns within a layer that additionally has polygonal cracks and fissures.
For more information about Kimmeridge Bay see the Purbeck Marine Wildlife Reserve Web Site.