I’m astonished by the power of the enormous cliff that appears as you walk around the coast from Blackwaterfoot on the Isle of Arran. The sill – the name given to a feature created by intrusive magma finding its way in between horizontal layers of sedimentary rock – is unique in its surroundings. Its columnar joints seem to still be on the move, powering up from within the Earth.
To me, a place like this has as much of the awesome force of the Earth’s heat engine as an active volcano – to generate such an enormous chunk of porphyritic rock needs a phenomenal amount of energy. The rock formed from magmatic crystal slush oozing out across between the horizontal layers of sedimentary rock which had been laid down millions of years before. There are interesting additions to the sill, too, with horizontal cracked dykes radiating out from the sides, digging deep into the sea a short distance away, rooting the sill to the spot.
I jump at the chance to walk along the base of the sill’s scree slope, with the magmatic rocks’ impressive, almost over-bearing, presence up above me. As it swallows half the sky with dark, vertical teeth, it reminds me a little of walking beneath the crags in Edinburgh’s Holyrood Park. I ponder once again the doors that open – like the folds and flaps in a picture book – once you learn a little of how to read a landscape. To be lucky enough to see the inner workings of the Earth drawn out on the surface, etched with millions of years’ worth of wind and water erosion and ice-carving, telling stories from beneath the surface.
Further along the coast and we find ourselves battling brambles and nettles to reach a dark, damp, tumble-down rockfall. On a now vertical slice of Triassic sandstone, 3 pointed, sharp toe prints appear, facing upwards. The pad of the foot is an indentation a few centimetres deep. The whole footprint measures around 16 centimetres long. It is thought to be the footprint of a Chirotherium – a crocodile-like creature which roamed a semi-arid landscape when Scotland lay just to the north of the equator around 270 million years ago.
I do wonder what she would have made of us, scrambling under overhanging tree-branches – all the time leaving our own shoed footprints in the iron-rich, red mud – to find the evidence of her own walk, albeit in a completely different environment, pressed into sand like an impression in playdoh.
All text and photographs copyright L. Reid 2015