AUSTIN, Texas
(Reuters) - When Texas geologist Earle McBride visited Omaha Beach in
Normandy, France, in 1988, four decades after D-Day, the visible
remnants of the Allied Forces' invasion there had long ago vanished.
But he and a colleague would
later discover the history of the June 6, 1944, invasion of Normandy's
beaches - which marked a turning point in World War Two - lingered in
the sand in the form of tiny pieces of shrapnel only visible under a
microscope.
It wasn't a discovery that
McBride and colleague Dane Picard of Utah set out to make during their
tourist visit to Omaha Beach, where U.S. forces suffered their greatest
casualties in the assault against heavily fortified German defenses.
"We didn't think about, ‘Hey, there should be shrapnel here?'" said
McBride, 80, a professor emeritus at the University of Texas who retired
in 2005 but still goes to his office five hours a day to study rocks.
But the geologists did what long
ago became their habit when they visit a beach anywhere in the world:
they put a bit of sand in a plastic bag and took it home.
McBride didn't fully analyze the
sample for more than two decades. Finally, in retirement, he made a
slide of the sand by using blue-dyed epoxy to bind the grains together.
On a recent day in his tiny
office at the Austin university where he taught for 46 years, McBride
showed a visitor what he found. Under a microscope, rounded grains -
quartz, feldspar, clam and oyster shells - were visible, along with
jagged-edged grains.
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"You see how angular that grain
is?" he asked. "It's an anomaly - if it had the same origin and history,
it should have been well-rounded, too."
A different light source on the
microscope revealed that the jagged-edged grains had a metallic sheen
and a rust-colored coating, and when McBride held a magnet to some of
the sand, the angular grains proved to be magnetic.
McBride suspected the jagged
grains were shrapnel, and he used a scanning electron microscope to
verify his hunch. It showed the grains were iron with a bit of oxygen
from rust.
He also found the sand included
small spherical iron and glass beads, which he and Picard believe were
formed by munitions explosions in the air and sand.
"It's a detective story," McBride said. "Sand has an exciting history."
He said it's not surprising that
shrapnel was left on the beach. Rather the surprise is that it remained
there decades later, long after the wrecked ships, tanks and aircraft
were gone.
A glass bead with divots and scratches |
But the shrapnel won't be in the sand forever, he and Picard wrote in Earth Magazine last year.
"The combination of chemical corrosion and abrasion will likely
destroy the grains in a century or so, leaving only the memorials and
people's memories to recall the extent of devastation suffered by those
directly engaged in World War II," they wrote.
The research by McBride and
Picard - a professor emeritus at the University of Utah - was published
in the September 2011 edition of The Sedimentary Record, a scholarly
journal.
"It was a great approach," said
Xavier Janson, a research scientist at the University of Texas and an
editor of the Record. "It was using a geological tool that you usually
use to understand where sand grains come from, but instead, it was used
to understand what happened on this beach."
For McBride, the discovery is an
example of why he still finds passion in his lifelong work studying
sedimentary rocks, the ones most commonly found on the earth's surface.
The latest project on his desk
is a 450-million-year-old rock from Utah roughly the size of a softball;
he's trying to reconstruct the history of how it formed and where its
grains originated.
The earth is old, McBride said,
and "all I can do is work on one little chunk of the history of
sandstones. As we say, so many rocks, so little time."
LSTs (Landing Ship Tanks), landing |
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