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The Structure of the Granophyric Quartz-Dolerite Intrusion of Centre 2, Ardnamurchan and the Problem of Net-Veining

Published online by Cambridge University Press:  01 May 2009

M. K. Wells
M. K. Wells
Affiliation:
Department of Geology, University College, London.
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Abstract

The Quartz-dolerite intrusion of Sgùrr nam Meann, Ardnamurchan, is shown to be a ring-dyke which has sill apophyses extending from its outer wall. This is a form of intrusion which has not been recognized before, and its field relations are described in detail. The quartz-dolerite is extensively veined by acid rocks which are ubiquitous in all parts of the intrusion, and most abundant in the sills. From the evidence of the distribution and nature of the veining it is concluded that the acid and basic components of the intrusion must have been ernplaced simultaneously. It is suggested that a gas-charged, acid residual magma may have separated from a crystallizing basic parent under the influence of sudden reductions of external pressure acting upon the system.

Type
Articles
Information
Geological Magazine , Volume 91 , Issue 4 , August 1954 , pp. 293 - 307
Copyright
Copyright © Cambridge University Press 1954

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References

REFERENCES

Emmons, R. C., 1940. The contribution of differential pressures to magmatic differentiation. Amer. Journ. Sci., ccxxxviii, 1–21.CrossRefGoogle Scholar
Fenner, C. N., 1948. Immiscibility of igneous magmas. Amer. Journ. Sci., ccxlvi, 465–502.CrossRefGoogle Scholar
Graton, L. C., 1945. Conjectures regarding volcanic heat. Amer. Journ. Sci., ccxliii A, 135–259.Google Scholar
Goransen, R. W., 1938. Silicate-water systems: phase equilibria in the NaAlSi3O8–H2O and KAlSi3O8–H2O systems at high temperatures and pressures. Amer. Journ. Sci., xxxv A, 71–91.Google Scholar
Grout, F. F., 1926. The use of calculations in petrology. Journ. Geol., xxxiv, 512–558.CrossRefGoogle Scholar
Holmes, A., 1936. The idea of contrasted differentiation. Geol. Mag., lxxiii, 228–238.CrossRefGoogle Scholar
Kennedy, W. Q., 1933. Trends of differentiation in basaltic magmas. Amer. Journ. Sci., xxv, 239–256.CrossRefGoogle Scholar
Reynolds, D. L., 1950. The Slieve Gullion volcano: a new interpretation of a Tertiary gabbro-granophyre complex. (Abstract of lecture to the Geological Society of London.)Google Scholar
Rickey, J. E., 1940. Association of explosive brecciation and plutonic intrusion in the British Tertiary igneous province. Bull. Volc., Ser. II, vi, 157–175.CrossRefGoogle Scholar
Rickey, J. E., and Thomas, H. H., 1930. Geology of Ardnamurchan, etc. Mem. Geol. Surv. Scotland.Google Scholar
Sederholm, J. J., 1926. On Migmatites and associated Pre-Cambrian rocks of South-Western Finland. Part II. Bull. Comm. Geol. Finlande, No. 77, 31–63.Google Scholar
Walker, F., and Poldervaart, A., 1949. Karoo dolerites of the Union of South Africa. Bull. Geol. Soc. Amer., lx, 591–706.CrossRefGoogle Scholar
Wells, M. K., 1951. Sedimentary inclusions in the Hypersthene-gabbro, Ardnamurchan, Argyllshire. Miner. Mag., xxix, 715–736.Google Scholar