2012
NH7661 : Leucogranite in Lewisianoid Rock
taken 13 years ago, near to Craighead, Highland, Scotland
Leucogranite in Lewisianoid Rock
South-west of here, the rocks are Moine-type metasediments, but from here to the north-east there are also rocks that look very much like the Lewisian rocks of the west coast and Hebrides. Not being in the recognised Lewisian area, they can't be called Lewisian, hence the rather cumbersome term Lewisianoid. This Lewisianoid boulder also contains pods of pink leucogranite, which has been stretched and streaked out as the host rock has been deformed deep down in the crust of the Earth. It shows three separate arrays of parallel markings. These are effectively cracks created when the rock was subjected to distorting movement, and later filled in by crystallising minerals, including pyrite or Fool's Gold.
The Rosemarkie Inlier
An inlier is a geological term denoting an outcrop of older rocks which protrudes through younger rocks. North-east of Rosemarkie is a curious inlier made up of rocks which closely resemble the Moine and Lewisian rocks further west, being made up of the same sorts of ancient rocks which have undergone similar metamorphoses. In the Rosemarkie Inlier, however, these rocks are intruded and cut by numerous sheets and veins of salmon-pink leucogranite. The inlier is about 10 km long and 2 km wide, and is bounded on the west by Devonian sedimentary rocks. It lies parallel to the continuation of the Great Glen Fault, which is just offshore, and is thought to have been uplifted into its present position by movements related to the Fault.
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- Grid Square
- NH7661, 28 images (more nearby 🔍)
- Photographer
- Anne Burgess (more nearby)
- Date Taken
- Saturday, 25 August, 2012 (more nearby)
- Submitted
- Thursday, 30 August, 2012
- Subject Location
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OSGB36:
NH 7601 6111 [10m precision]
WGS84: 57:37.3711N 4:4.6593W - Camera Location
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OSGB36: NH 7601 6111
- View Direction
- Northeast (about 45 degrees)
