Late last year, I reported on the strange interactions of sand and ice on the shores of Lake Superior and 500-million-year-old beaches. Recently, I heard from my friend, Larry Deemer, beach-side resident of New York and meticulous observer of his environment’s shifting moods and forms, describing phenomena that are reminiscent of these bizarre structures. I included some of Larry’s spectacular photographs of sand patterns early in the history of this blog, and his report of his winter beach ramblings was accompanied by further examples. As he wrote:
Last month I discovered an unusual sand formation after the snow and ice on the beach melted. What remained was a very thin crust of sand that was suspended over more hard pack sand underneath. The formations were large, almost as if they were advancing bulkheads, like a glacier.
It seems to me that these slabs of encrusted sand reflect freezing and winnowing processes similar to those occurring on the beaches of the Great Lakes – perhaps with the behaviour of salty water as an additional component in the equation. Larry also enclosed photos of similar “fragile, self-supported designs” but “on a smaller and flatter scale” from another morning following a freezing night: