A traveler expects to sample a local cuisine that has its origins in local ingredients, and it’s no different with sand. Relaxing on a beach in North Carolina or the south coast of England, looking at the sand between your toes, you would hardly expect it to be made of bits and pieces thrown out of a volcano. Trekking along the coast of Greenland, you would be surprised if the sand were composed of the debris from a coral reef. What you do find are sand grains of predominantly local parentage. On the Normandy beaches where D-day landings took place, you will find sand-sized fragments of steel.
In 2009, for the first time, I visited the Normandy beaches – and the memorials and the cemeteries – and posted a brief report in September last year. I mentioned again the fragments of steel, shrapnel sand grains, but have never convincingly located any in the samples that I have looked through. Now the latest issue of Earth Magazine carries an article titled “D-Day's Legacy: Remnants of invasion linger in beach sand.” In it, two sedimentary petrologists, Earle F. McBride and M. Dane Picard, describe their visit to the D-Day beaches and the analysis of the sands from Omaha after their return to the laboratory – “Little did we know what we would find when we got home and started studying the sand.”
A thin section of the sand revealed a large number of angular opaque grains that were magnetic. Shard-like, they were only slightly rounded. Some were well-laminated. These grains were also associated with small spherical beads of iron and glass. At first, we were uncertain of what we were looking at. However, in a few days, we concluded that the metal and glass particles were human-made — particles generated from the explosions of munitions during the Normandy landings. After further testing, we determined the sand does indeed contain 4 percent shrapnel and trace amounts of beads of metal and glass. Because waves and currents on any given day can selectively concentrate sand grains of a given specific gravity, we cannot be certain that our sample is representative of the entire beach — that shrapnel grains make up 4 percent of Omaha sand as a whole.
They go on to describe the likely origin of the glass grains as being from explosions in the sand – with the critical contribution of seawater salts as a flux that lowered the melting point of the quartz. Read the whole article, it’s well worth it.
So tomorrow, we remember – please – the events of that day in 1944. And perhaps should you visit those broad calm beaches as they appear now, think of that granular legacy, those witnesses beneath your feet.