Glac Mhor - Columnar basalt

Afternoon walk today was to Glac Mhor, north of Tobermory. Its a small inlet on Bloody Bay and easily accessible by a rather obscure path through the Ardmore Forest. The great thing about this are is that you can find nice columnar basalt here  - nothing on the scale of Staffa or Ulva, but it is columnar nonetheless . It is mentioned in the Mull Memoir (Bailey et al, 1924)

Here are some photos of the area - as well as the columnar basalt there were a couple of other goodies on the way back!

General view looking down on Glac Mhor

Two view looking over to Ardnamurchan from the shore

A view of the columnar basalt at the shore. Some close up pics next:

Columnar structure is well seen.

And another couple of pics of this rock:

Ben Hiant in the distance there

From the shore I walked up the slope back towards the forest. There is an amazing dyke on the way. It is one of the "Mull Swarm" Palaeocene dykes but is seriously feldspar-phyric. SOme massive phenocrysts in there. Here are a couple of general views:

 At the lower end of the dyke looking up - sun was in the wrong position for a decent pic

And here is the upper end of it a bit further up the hill:

Some pics of the phenocrysts:

20p coin for scale.

The dyke has been cored - there are a couple of holes high up in a really awkward spot. Must have been fun trying to get them. Anyway, there are plenty of big pieces lying about - would be nice to get a bit sectioned some day

From there it was back over the hill and through the forest back to the car. On the way, there is a really nice example of spheroidal weathering in the side of a forestry track:

A great little afternoon stroll!


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