Geoscience Reference
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has been devastated by the plague (it was the gateway for the Black
Death into Europe) and by earthquakes.
Another catastrophe that happened far longer ago was discerned
by geologist Giuliano Ruggieri in the 1960s, as he walked among the
strata exposed in the crags and cliffs of the rugged local landscape.
Among them were the picturesque cliffs and bay of Eraclea Minoa
named—local legends differ—possibly after Heracles (Hercules), or
alternatively after Minos, the ancient king of Crete. In those cliffs
there are beautifully displayed strata from the late Miocene and
Pliocene epochs. Some 5-8 million years old, they represent a deep-
sea floor of that time, now pushed up above sea level by the tectonic
forces that are squeezing the Mediterranean shut. Among them are
layers of gypsum—calcium sulphate—one of the minerals that forms
when seawater evaporates.
Perhaps, said Ruggieri, the whole Mediterranean then dried up. It
was a prophetic statement. It looked back, too, to earlier legends.
Pliny the Elder had recounted a story that there used to be mountains
blocking the Straits of Gibraltar, until Hercules (that man again!) dug
a passage so that the Atlantic waters could flow in. In the 1920s
H. G. Wells thought on how nature, rather than assiduous super-
heroes, might have acted to similar effect. He noted that the global sea
level dropped by over 100 metres at the height of the last Ice Age. That
would block inflow at the narrow Straits, he thought, and make the
Mediterranean largely dry up—before the post-glacial sea level rise
brought the sea back in. His logic was good but his bathymetry was
out, as the channel stayed deep enough throughout the Ice Ages to
maintain constant connection with the ocean. Robert E. Howard,
meanwhile, just had fun with the idea, having his own superheroes
Conan the Barbarian and Red Sonja carry out their feats of derring-do
in the far-off Hyborian Age, across a wide landscape centred on a dry
Mediterranean.
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