Another look at the tree

I mentioned in an earlier post about the presence of a fossil tree in the grounds of the Western Isles Hotel in Tobermory, Isle of Mull. I had heard about it from people over the years but never had a close look at it. I went back today to take some pictures and to get a close up view of it. Earlier pictures that I posted on Twitter got the repsonse that it looks more like a fracture zone than a tree. Here are some pictures taken today in good weather, with a ruler for scale

General view of the feature from below - a bed of ivy twigs forms a spongy bed in the foreground. Total height of the structure is about 4 metres


 A close up view of the structure - vesicular basalt on both sides of it


Ruler for scale in this pic. Showing numerous sub parallel veins running vertically


Another close up view of the edge of the structure - veins look like calcite


Another similar view, right on the edge


A final view before leaving - ruler shows width - about 30cm



And a close up of the same

So whats the verdict, all you geologists out there? Tree or Fracture Zone?  Any constructive comments are very welcome!

NOTE: This part of the grounds of the hotel are not accessible without permission. I had to get the OK from  the hotel manager to visit this location.


Comments

Unknown said…
Really interesting feature James, though I think its likely to be something structural as apposed to a tree, the fractures seem to propagate in depth and length, as well as a lack of cooling evidence - lighter bleached looking basalt at the contact or propagating cooling fractures etc.

Some sort of dilation breccia possibly - with zeolite infilling the fractures?
21 February 2018 at 14:55
Mull Geology said…
Jess

I was wondering about the infilling stuff. Calcite was my first thought but as you say, maybe zeolite. I didnt grab a sample as I decided just to leave it well alone but getting a small piece probably wouldnt be too hard and wouldnt involve hammering. Wne you are over we could go and have a look if you like. Its easy to get to
22 February 2018 at 00:15
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