Knockan Crag - Geological Significance

Geological Significance

During the 19th century prominent geologists conducted a prolonged and bitter debate about the fault line exposed here. The argument was primarily between Roderick Murchison and Archibald Geikie on the one hand and James Nicol and Charles Lapworth on the other. This was finally resolved by the work of Ben Peach and John Horne whose 1907 paper on the subject remains a classic text.

The main issue was that the Moine schists at the top of the crag appeared to be older than the Cambrian and Ordovician rocks such as Durness limestone lower down. Murchison and Geikie believed the sequence was wrong and that the Moine schists must be the younger rocks. The conundrum was explained by the action of a thrust fault - this being the first to be discovered anywhere in the world. The older rocks had been moved some 70 kilometres to the west over the top of the younger rocks due to tectonic action.

A monument to Peach and Horne's work was erected by the international geological community at Inchnadamph a few miles to the north.

Read more about this topic:  Knockan Crag

Famous quotes containing the words geological and/or significance:

    The crystal sphere of thought is as concentrical as the geological structure of the globe. As our soils and rocks lie in strata, concentric strata, so do all men’s thinkings run laterally, never vertically.
    Ralph Waldo Emerson (1803–1882)

    The hypothesis I wish to advance is that ... the language of morality is in ... grave disorder.... What we possess, if this is true, are the fragments of a conceptual scheme, parts of which now lack those contexts from which their significance derived. We possess indeed simulacra of morality, we continue to use many of the key expressions. But we have—very largely if not entirely—lost our comprehension, both theoretical and practical, of morality.
    Alasdair Chalmers MacIntyre (b. 1929)