Early (well…) on Wednesday we drove a couple of miles up the road to the Eildon Hills – a journey which in no way involved travelling along a road that was closed for maintenance. We parked by the reservoir to the West of the Eildons – probably the best spot to start a walk.
Our Transport - The Green Blur, and our mascot - Trevor the Trilobite
Once again we were incredibly pushed for time; so much so that we didn’t have time to climb up the Eildons, instead contenting ourselves with a view from afar. However, that didn’t stop us from examining some of the geology of the area. Across the road from where we parked is Bowdenmoor Quarry; a quarried mass of Sanidine-Trachyte in Silurian country rocks which shares its origin with the Eildon Hills themselves. They were all part of the same intermediate-acidic layered lacolith (with one exception, which I’ll get to shortly).
The Quarry (picture by Hazel Scott)
I collected some nice samples of Sanidine-Trachyte here:
Sanidine-trachyte - note the phenocrysts
Since we had to get moving, we headed up the road, but not before snapping some more pics.
The Mid (lacolith) and Little (vent) Hills
The largest hill (left) is a part of the lacolith, consisting of layered sheets of trachyte and felsite (I wish we’d had time to get a bit of the Riebeckite-felsite). The smaller hill on the right (which isn’t usually counted as one of the three Eildon hills) is actually a volcanic vent intruded later. It consists of a central core of basalt and quartz-porphyry as well as some agglomerate.
Before getting in the car to drive across to the west coast (via Dob’s Linn) we couldn’t pass up the opportunity for another photo.
Emma and I in front of the Wester Hill
Behind us is the reservoir (which I think is man-made) and behind that is the Wester Hill – another part of the lacolith.
Tags: Borders, Borders09, Carboniferous, Devonian, Geology, Silurian
[...] In addition to popping down to the coast we also finally climbed the Eildons (after not managing it last time). Unfortunately, from a geological standpoint this wasn’t too exciting as the rock outcrops [...]