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The geology of the Vesturhorn Intrusion, SE Iceland

Published online by Cambridge University Press:  01 May 2009

M. J. Roobol
M. J. Roobol
Affiliation:
Geology DepartmentUniversity of the West IndiesMonaKingston 7Jamaica
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Summary

The Vesturhorn Intrusion, exposed over 19 km2 of the south-eastern coast of Iceland, comprises two mafic complexes and a central core of epigranites. The latter can be subdivided into a central area with a flat-lying sheet structure, surrounded and separated from the mafic complexes by a more massive belt called the Transitional Epigranites with variable colour index and containing many rounded-to-angular inclusions and net-veined complexes. The consideration of several lines of evidence suggests that the components were emplaced as magmas in the sequence, first the epigranites with a sheet structure and second the basic complexes. The Transitional Epigranites appear to have originated by the remobilization and local hybridization of the early, sheet-structured epigranites. The relatively large volume of remobilized material and an absence of partially melted zones are considered to result from the early epigranites being still partially molten at the time of emplacement of the mafic complexes, together with a ponding of remobilized material beneath the chamber roof. A final intrusive episode occurred with the emplacement of a body of fayalite—hedenbergite epigranite largely into the Transitional Epigranites, probably after the consolidation of the latter.

Type
Articles
Information
Geological Magazine , Volume 111 , Issue 4 , July 1974 , pp. 273 - 286
Copyright
Copyright © Cambridge University Press 1974

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References

Bailey, E. B. 1956. Hebridean Notes: Rhum and Syke. Lpool Manchr geol. Jl 1, 420–6.CrossRefGoogle Scholar
Blake, D. H. 1966. The net veined complex of the Austurhorn Intrusion, S.E. Iceland. J. Geol. 74, 891–907.CrossRefGoogle Scholar
Brown, G. M. 1956. The layered ultrabasic rocks of Rhum, Inner Hebrides. Phil. Trans. R. Soc. Lond. B 240, 1–53.Google Scholar
Cargill, H. K., Hawkes, L. & Ledeboer, J. A. 1928. The major intrusions of S.E. Iceland. Q. Jl geol. Soc. Lond. 84, 505–39.CrossRefGoogle Scholar
Ferguson, J. & Pulvertaft, T. C. R. 1963. Contrasting styles of igneous layering in the Gardar Providence of S. Greenland. Spec. Pap. Miner. Soc. Am. 1, 10–22.Google Scholar
Gale, N. H., Moorbath, S., Simons, J. & Walker, G. P. L. 1966. K-Ar ages of acid intrusive rocks from Iceland. Earth Planet. Sci. Lett. 1, 284–92.CrossRefGoogle Scholar
Geikie, A. 1897. The Ancient Volcanoes of Great Britain, vol. 2. London.CrossRefGoogle Scholar
Gianetti, G. 1972. Cumulus textures of Midhyrna layered intrusion, Snaefellsnes peninsula, W. Iceland. Bull. Soc. geol. Ital. 91, 419–38.Google Scholar
Harker, A. 1908. The geology of the Small Isles of Inverness-shire. Mem. Geol. Surv. U.K.Google Scholar
Hess, H. H. 1960. Stillwater igneous complex, Montana: a quantitative mineralogical study. Mem. geol. Soc. Am. 80, 230 pp.Google Scholar
Johnson, R. W. 1968. A granophyre stock in S.E. Iceland and the distribution of epidote around it. Visindafelag Islendinga. 53– 9.Google Scholar
Moorbath, S., Sigurdsson, H. & Goodwin, R. 1968. K-Ar ages of the oldest exposed rocks on Iceland. Earth Planet. Sci. Lett. 4, 197–205.CrossRefGoogle Scholar
Reynolds, D. L. 1954. Fluidisation as a geological process and its bearing on the problem of intrusive granites. Am. Jl Sci. 252, 577–614.CrossRefGoogle Scholar
Roobol, M. J. 1971. Some relations between common acid-basic associations. Geol. Mag. 108, 525–31.CrossRefGoogle Scholar
Roobol, M. J. 1972. Size-graded, igneous layering in an Icelandic intrusion. Geol. Mag. 109, 393–404.CrossRefGoogle Scholar
Tomkieff, S. I. 1942. The Tertiary lavas of Rhum. Geol. Mag. 79, 1–13.CrossRefGoogle Scholar
Thompson, R. N. & Patrick, D. J. 1968. Folding and slumping in a layered gabbro. Geol Jl 6, 139–46.CrossRefGoogle Scholar
Wager, L. R., Vincent, E. A., Brown, G. M. & Bell, J. D. 1965. Marscoite and related rocks of the Western Red Hills Complex, Isle of Skye. Phil. Trans. R. Soc. Lond. A 257, 273–307.Google Scholar
Walker, G. P. L. 1964. Geological investigations in E. Iceland. Bull. Volcan. 27, 3–15.CrossRefGoogle Scholar
Wells, M. K. 1953. The structure and petrology of the hypersthene gabbro intrusion, Ardnamurchan, Argyllshire. Q. Jl geol. Soc. Lond. 109, 367–97.CrossRefGoogle Scholar