The
shaping of
the mountains
For thirty million long years the granites had waited in darkness for
the elements to weather away, grain by grain, the mile of rock under which
they were imprisoned. On the surface above and across the earth new orders
of life were evolving.
Then, at one moment in unmeasured time, as a final fragment of their
cover was washed or blown or scraped away, light pierced down into the
rock through the first clear quartz to glint in the sun;  at
some spot in the ancient landscape the patient granites emerged at last
into the realm of light and life, ahead of them the many long millennia
that it would take to shape them into the Mountains of Mourne.
The granite which today grips the walker’s boot, and shapes the
scenery that uplifts his spirit, took form in the era of cataclysm that
began 65 million years ago and which lasted for a quarter of that time.
A sabre-tooth tiger, or one of man’s earliest primate ancestors,
could have set the first living foot on the granite of Mourne when it
appeared on the surface of a sub-tropical Irish landscape. Acacia, cinnamon
and palm rooted in its soils. Granite would have rotted away quickly in
the warm, moist conditions but those days were almost at the end of Ireland’s
time in such a climate. Global temperatures were falling, Europe continued
its long drift north, carrying Ireland into cooler latitudes.
The countless years rounded the sharp edges of the massive blocks and
planed flat platforms around the emerging peaks; they turned the fractures
of their ancient cooling into gullies and valleys and washed their crystal
fragments down them to the seas.
The long shaping of the Mountains of Mourne to their present outlines
was virtually complete when a million and a half arctic years chilled
the once warm granite to its heart, splintering the rock faces and driving
life from the valleys and slopes.
The moving ice, sometimes from the north and sometimes the west, at times
higher than most of the mountains themselves, scraping round their flanks,
squeezing between them, jousted with the glaciers spilling from the high
corries for possession of the valleys. Their skirmishes left behind a
mountain world of elegant curves, aloof rock buttresses with spreading
skirts of splintered debris, boulders perched high above their birthplace
and valleys layered with the pulverised rocks of the surfaces over which
the ice had ground its way. These swathes and mounds of sands, gravels
and boulders in chaotic mix, were left to coat the mountain hollows as,
15,000 years ago, the last ice sheets lifted their siege and melted away,
defeated by a returning warmth that still prevails.
The ice returned to the oceans; life returned to the mountains.
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