Scotland: Two Acts of Union
Scotland – well before the Union
“Scotland’s
landscape
tells a story
of a journey
from deep in
the southern
hemisphere
over 500
million
years ago to
our present
position on
the globe.”
In this referendum year, it
is pertinent to look back on
Scotland’s past. Not just to those
years documented in history
books, but back further to look at
the story written in the rocks and
landscapes that record a history
stretching back through ‘deep
time’. Deep time was a concept
recognized by James Hutton,
the ‘Father of Modern Geology’,
who lived in Edinburgh a little
over 200 years ago. Like many
who lived through the Scottish
Enlightenment, he was a polymath,
interested in a wide range of topics
stretching from his initial education
in medicine, through chemistry
and his work on producing
the chemical sal ammoniac,
to his love of agriculture. On
the way, he produced some
fundamental thoughts on the
nature of geological time and on
the processes that formed the
Earth. These ideas today form
the foundation of our modern
understanding of how the Earth
works, a concept geologists
describe as ‘plate tectonics’.
Hutton conceived that geological
time had to be very much greater
than the 6,000 years envisaged
by Archbishop Ussher of Armagh.
He saw the rocks at Siccar Point
in Berwickshire as being the key
evidence of major compressions
forming mountains, followed by a
long period of erosion before the
next set of rocks were laid down.
He also recognized that volcanoes
could produce molten rock, and
that this had to be driven by a ‘heat
engine’ in the Earth’s core.
When Alfred Wegener, a German
polar explorer and meteorologist,
in 1912 first proposed the idea
that continents could move, the
scientific world ridiculed him. This,
despite the evidence from the
geographical fit of Africa and South
America, and strong scientific
evidence in the distribution of
fossil plants and land-living animals
on either side of major oceans
suggesting that these continents
had at one time been joined. They
had forgotten the significance of
Hutton’s heat engine.
From these beginnings in Alfred
Wegener’s theory of ‘continental
drift’ emerged the unifying
paradigm of plate tectonics which
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Professor Stuart Monro FRSGS, Scientific Director, Our Dynamic Earth
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ARMORICA ??
Location of the Caledonian/Acadian mountain chains in the Early Devonian Epoch. Present day coastlines are
shown for reference. Red lines are sutures, capitalized names are the different continents/super-terranes that
joined during the Caledonian orogeny.
involved many scientists globally.
In North America, Marie Tharp
showed the dramatic topography
of the ocean floor with midocean ridges and deep trenches.
Two young British geophysicists,
Frederick Vine and Drummond
Matthews, and also, independently,
Lawrence Morley of the Canadian
Geological Survey,