Hunting down something interesting

Dr John Faithfull had emailed some interesting photomicrographs of what was reported as being from a sill near Torrans in SW Mull. The slides show broken plagioclase and cpx crystals that look like they are from something explosive. According to the info I had, it was from a sill. Since I had a bit of time and was in the area. I decided to have a look to see if I could find the original location

The Grid Ref I was given was NM499241 and near a waterfall. There are several waterfalls in this area. Here are the first, just next to a rough track























The sill is obvious with the waterfall running over it. I took a sample of the rock but it doesnt look too exciting - looks pretty typical of dolerite sills





The top waterfall / sill in close up


























The other sill is just below it. Got a sample of this as well and it doesnt look an awful lot different

There is another waterfall in the general area, just downstream a bit:






















The sill forms an obvious band where the waterfall is























Here is the top surface of it, showing a roughly columnar structure

Again,  a sample of it was taken but didnt really look too exciting

So I need to consult with John to see what he thinks.

There was another waterfall on the walk back out:























Quite bleak terrain in that area but the waterfalls add a bit of variety to it. Easy to get to as well - the estate road makes for straightforward access. A good afternoon stroll!


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