Читать книгу Walking the Corbetts Vol 2 North of the Great Glen онлайн

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The remarkable thing about these rocks is that the fossils are identical to those found in the Appalachian Mountains in the US but distinct from those of the same age in the rest of Britain. It is now clear that 500 million years ago Scotland, Scandinavia, Greenland and north-east America were one continent and that they were on the opposite sides of a now vanished Lapetus Ocean to the rest of Europe. This was the first conclusive evidence for continental drift.

About 430 million years ago there were intrusions of magma creating sills of crystalline rock parallel to the bedding plane, dykes cutting the bedding plane as well as plutons (irregular masses).

Between 430 and 420 million years ago a vast mountain range was being built up to the south-east as the Lapetus Ocean had closed and the ‘European plate’ was moving north-west and colliding with Laurentia. The most dramatic effect on Scotland was the pushing of a large slab of the old Moine schists over the younger rocks of north-west Scotland. This is known as the Moine Thrust.