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III.—A Petrological Study of the Arthur's Seat Volcano*

Published online by Cambridge University Press:  06 July 2012

R. H. Clark
Affiliation:
Grant Institute of Geology, University of Edinburgh

Synopsis

Arthur's Seat is the remains of a dissected Lower Carboniferous volcano, from which were erupted a series of basaltic rocks representative of the province to which it belongs. The rocks occur as lavas, intrusions and tuffs, and include basalts of Dalmeny, Jedburgh, Dunsapie, Craiglockhart and Markle types, in addition to mugearite. For convenience the basalts of Dunsapie type have been subdivided into Normal and Feldspathic varieties.

The volcano has been remapped; some minor departures from the six-inch Geological Survey map are recorded and certain changes in the numbering and classification of the lavas have been made.

The petrographic characters of the various volcanic rocks are described in detail, with modal and chemical analyses. The composition of the parental magma of the volcano was probably very similar to that of Normal Dunsapie basalt. Markle and Craiglockhart types were produced as complementary differentiates of the parental liquid by a process of gravity differentiation, in which sinking of ferromagnesian crystals, particularly augites, played an important part. The basalts of Dalmeny and Jedburgh types, which in Arthur's Seat have strong chemical resemblances, probably represent only slightly differentiated parental magma. Concentrations of soda-rich volatiles produced intense albitisation in the Markle basalts and the mugearites. It is considered that the mugearites of Arthur's Seat crystallised initially as Jedburgh or Dalmeny types, and were altered to their present state during a deuteric phase.

An attempt has been made to reconstruct the eruptive history of the volcano. The magma source appears to have been replenished with parental magma at least twice during the period of activity. The first and last eruptions were of Dunsapie basalt; the albitised products appeared at a fairly late stage.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1956

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Footnotes

Now Professor of Geology at Victoria University College, University of New Zealand, Wellington, N.Z.

*

Thanks are due to the Carnegie Trust for the Universities of Scotland for a grant towards the cost of the publication of this paper.

References

References to Literature

Allport, S., 1874. “On the microscopic structure and composition of British Carboniferous dolerites”, Quart. J. Geol. Soc. Lord., 30, 629–567.Google Scholar
Atkinson, S., 1619. The Discoverie and Historie of the Gold Mines of Scotland. Edinburgh. An edition published by the Bannatyne Club in 1825.Google Scholar
Bailey, E.B., 1910. In “The geology of East Lothian”, Mem. Geol. Surv. Scotland. Google Scholar
Bailey, E.B 1923. “Volcanic vent parasitic on St Leonard's sill”, Trans. Edin. Geol. Soc., 11, 223229.CrossRefGoogle Scholar
Bailey, E.B., and Grabham, G. W., 1909. “Albitisation of basic plagioclase feldspars”, Geol. Mag., 6, 250256.Google Scholar
Barth, T. F. W., 1936. “The crystallisation process of basalt”, Amer. J. Sci., 31, 321–251.CrossRefGoogle Scholar
Bonney, T.G., 1878. “Notes on the relations of the igneous rocks of Arthur's Seat”, Proc. Geol. Assoc., 5, 112.Google Scholar
Boué, A., 1820. Essai Géologique sur l'Ecosse. Paris.Google Scholar
Bowen, N. L., 1928. The Evolution of the Igneous Rocks. Princeton.Google Scholar
Campbell, R., 1914. “On the occurrence of petrified plant remains in the Lion's Head vent, Arthur's Seat”, Trans. Edin. Geol. Soc., 10, 248.Google Scholar
Campbell, R., Day, T.C., and Stenhouse, A. G., 1934. “The Braefoot Outer Sill, Fife (Pt. 2)”, Trans. Edinb. Geol. Soc, 13, 148173.Google Scholar
Clark, R. H., 1952 a. ”The significance of flow structure in the microporphyritic ophitic basalts of Arthur's Seat”, Trans. Edinb. Geol. Soc., 15, 6983.Google Scholar
Clark, R. H. 1952 b. Petrological Studies of the Lavas and associated Rocks of the Arthur's Seat Volcano, Ph.D. Thesis in Library of University of Edinburgh.Google Scholar
Day, T.C, 1912. “Some observations on the Long Row and the Dasses, Arthur's Seat”, Trans. Edinb. Geol. Soc., 10, 4048.CrossRefGoogle Scholar
Day, T.C., 1923. “Note on the exposure of St Leonard's Craig, at No. 39 St Leonard's Hill”, Trans. Edinb. Geol. Soc. 11, 266267.Google Scholar
Day, T.C., 1933. Arthur's Seat, a Ruined Volcano. Edinburgh.Google Scholar
Flett, J. S., 1910. “The geology of the neighbourhood of Edinburgh” (2nd Ed.), Mem. Geol. Surv. Scotland. Google Scholar
Geikie, A., 1861. “The geology of the neighbourhood of Edinburgh”, Mem. Geol. Surv. Gt. Britain. Google Scholar
Geikie, A., 1880. “On the Carboniferous volcanic rocks of the basin of the Firth of Forth—their structure in the field and under the microscope”, Trans. Roy. Soc. Edinb., 29, 437519.CrossRefGoogle Scholar
Geikie, A., 1892. “Anniversary Address of the President”, Proc Geol. Soc. London, 189192, 38179, in Quart. J. Geol. Soc., 48.Google Scholar
Geikie, A., 1897. The Ancient Volcanoes of Great Britain. (2 vols.) London.Google Scholar
Hall, J., 1805. “Experiments on whinstone and lava”, Trans. Roy. Soc. Edinb., 5, 43.Google Scholar
Harker, A., 1902. Petrology for Students. Cambridge.Google Scholar
Henderson, J., 1880. “On the structure and arrangement of the rocks of Arthur's Seat”, Trans. Edinb. Geol. Soc., 3, 222244.Google Scholar
Hess, H. H., 1949. “Chemical composition and optical properties of common clino-pyroxenes”, Amer. Min., 34, 621666.Google Scholar
Hutton, J., 1789. “Of certain natural appearances of the ground on the hill of Arthur's Seat”, Trans. Roy. Soc. Edinb., 2, 3.CrossRefGoogle Scholar
Jameson, R., 1805. A Mineralogical Description of the County of Dumfries. Edinburgh.Google Scholar
Judd, J. W., 1875. “On the structure and age of Arthur's Seat, Edinburgh”, Quart. J. Geol. Soc. London, 31, 131148.Google Scholar
Kennedy, W. Q., 1933. “Composite auto-intrusion in a Carboniferous lava flow”, Sum. Progr. Geol. Surv. Gt. Britain, 1932, Pt. II, 8393.Google Scholar
MacGregor, A. G., 1928. “The classification of Scottish Carboniferous olivine-basalts and mugearites”, Trans. Geol. Soc. Glasg., 18, 324360.CrossRefGoogle Scholar
MacGregor, A. G., 1932. “Note on corroded ferromagnesian phenocrysts in a Scottish basalt”, Trans. Edinb. Geol. Soc., 12, 329333.Google Scholar
MacGregor, A. G., 1936. “The composite sill of St Leonard's Craig and Heriot Mount, Edinburgh”, Trans. Edinb. Geol. Soc., 13, 317331.CrossRefGoogle Scholar
Maclaren, C., 1834. “On Arthur's Seat, the Environs of Edinburgh and Calton Hill”. Five articles in The Scotsman.Google Scholar
Maclaren, C., 1839. Geology of Fife and the Lothians. Edinburgh.Google Scholar
Maclaren, C., 1866. Geology of Fife and the Lothians. Edinburgh. 2nd Ed. Google Scholar
Oertel, G., 1952. “A structural investigation of the porphyritic basalts of Arthur's Seat, Edinburgh”, Trans. Edinb. Geol. Soc., 14, 360378.Google Scholar
Peach, B. N., 1910. “The geology of the neighbourhood of Edinburgh” (2nd Ed.), Mem. Geol. Surv. Scotland. Google Scholar
Peach, B. N., 1911. “Description of Arthur's Seat Volcano”, Mem. Geol. Sun. Scotland. Google Scholar
Peach, B. N., 1921. “Description of Arthur's Seat Volcano” (2nd Ed.), Mem. Geol. Sun. Scotland. Google Scholar
Rutledge, H., 1952. “A petrological note on a composite sill, the Dasses, Arthur's Seat”, Trans. Edinb. Geol. Soc., 14, 379388.Google Scholar
Teall, J. J. H., 1888. British Petrography. London.Google Scholar
Tomkeieff, S. I., 1937. “Petrochemistry of the Scottish Carboniferous-Permian igneous rocks”, Bull. Volcan. (2), 1, 5987.Google Scholar
Tomkeieff, S. I., 1940. “The basalt lavas of the Giant's Causeway District of Northern Ireland”, Bull. Volcan. (2), 6, 89143.Google Scholar
Tomkeieff, S. I., 1945. “Petrology of the Carboniferous igneous rocks of the Tweed Basin”, Trans. Edinb. Geol. Soc., 14, 5375.Google Scholar
Tomkeieff, S. I., “Nepheline-basanite of Southdean, Roxburghshire”, Trans. Edinb. Geol. Soc., 14, 349359.Google Scholar
Townson, R., 1799. Traits and Observations in Natural History and Physiology. London.Google Scholar
Tyrrell, G. W., 1913. “The petrology of the Kilpatrick Hills, Dunbartonshire, with notes on the Scottish Carboniferous basalts”, Trans. Geol. Soc. Glasg., 14, 219257.Google Scholar
Tyrrell, G. W., 1917. “The igneous geology of the Cumbrae Islands”, Trans. Geol. Soc. Glasg., 16, 244274.Google Scholar
Zirkel, F., 1870. Mikroskopische Struktur und Zusammensetzung der Basaltgesteine. Bonn.Google Scholar