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A note on the age and pyroxene chemistry of the igneous rocks of the Shelve Inlier, Welsh Borderland

Published online by Cambridge University Press:  01 May 2009

B. D. T. Lynas ,
C. C. Rundle  and
R. W. Sanderson
B. D. T. Lynas
Affiliation:
British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K.
C. C. Rundle
Affiliation:
British Geological Survey, 64 Gray's Inn Road, London WC1X 8NG, U.K.
R. W. Sanderson
Affiliation:
British Geological Survey, Exhibition Road, London SW7, U.K.
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Abstract

Geological survey, electron microprobe analyses of clinopyroxenes and isotopic age determinations have revealed that the intrusive dolerites and basic–intermediate lavas of the Shelve Ordovician Inlier are part of a co-magmatic suite which show transitional affinities between tholeiites and alkali basalts. The ages of most of the intrusives are shown to be mid-Ordovician.

Type
Articles
Information
Geological Magazine , Volume 122 , Issue 6 , November 1985 , pp. 641 - 647
Copyright
Copyright © Cambridge University Press 1985

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References

Basaltic Volcanism Study Project. 1981. Basaltic Volcanism on the Terrestrial Planets. New York: Pergamon Press Inc. 1286 pp.Google Scholar
Bevins, R. E. & Rowbotham, G. 1983. Low-grade metamorphism within the Welsh sector of the para-tectonic Caledonides. Geological Journal 18, 141–67.CrossRefGoogle Scholar
Bevins, R. E., Kokelaar, B. P. & Dunkley, P. N. 1984. Petrology and geochemistry of lower to middle Ordovician igneous rocks in Wales: a volcanic arc to marginal basin transition. Proceedings of the Geologists' Association 95 (4), 337–47.CrossRefGoogle Scholar
Blyth, F. G. H. 1944. Intrusive rocks of the Shelve area, south Shropshire. Quarterly Journal of the Geological Society of London 99, 169–204.CrossRefGoogle Scholar
Blyth, F. G. H. 1948. Pyroxene from the Squilver dolerite, south Shropshire. Mineralogical Magazine 28, 380–3.CrossRefGoogle Scholar
Brown, G. M. 1967. Mineralogy of basaltic rocks. In Basalts, vol. 1 (ed. Hess, H. H. and Poldervaart, A.), pp. 103–62. New York: Wiley Interscience.Google Scholar
Kokelaar, B. P., Howells, M. F., Bevins, R. E., Roach, R. A. & Dunkley, P. N. 1984. The Ordovician marginal basin of Wales. In Marginal Basin Geology: Volcanic and associated sedimentary and tectonic processes in modern and ancient marginal basins (ed. Kokelaar, B. P. and Howells, M. F.), pp. 245–69. Special Publication of the Geological Society of London.Google Scholar
Lapworth, C. & Watts, W. W. 1894. Shropshire. In Geology in the Field (4) (ed. Monckton, H. W. and Herries, R.), pp. 739–69. London: Geologists' Association, Jubilee volume.Google Scholar
Lapworth, C. & Watts, W. W. 1910. The geology of south Shropshire. Proceedings of the Geologists' Association 13, 297–355.CrossRefGoogle Scholar
Lynas, B. D. T. 1983. Two new Ordovician volcanic centres in the Shelve inlier, Powys, Wales. Geological Magazine 120 (6), 535–42.CrossRefGoogle Scholar
Odin, G. S. 1984. Revision of the Lower Palaeozoic time scale Bulletin of Liaison and Information. I.G.C.P. Project no. 196/3, 25–6.Google Scholar
Pearce, J. A. & Cann, J. R. 1973. Tectonic setting of the basic rocks determined using trace element analyses. Earth and Planetary Science Letters 19, 290–300.CrossRefGoogle Scholar
Rundle, C. C. 1984. Radiometric dating of a Caradocian tuff horizon. Bulletin of Liaison and Information. I.G.C.P. Project no. 196/3, 26–31.Google Scholar
Steiger, R. H. & Jäger, E. 1977. Subcommission on geochronology: convention on the use of decay constants in geo and cosmochronolgy. Earth and Planetary Science Letters 36, 359–62.CrossRefGoogle Scholar
Strachan, I. 1981. The sequence of graptolite faunas in the Ordovician of the Shelve Inlier, Welsh Borderland. Acta Palaeontologica Polonica 26 (1), 19–25.Google Scholar
Watts, W. W. 1887. A Shropshire picrite. Report of the British Association (Manchester), 700.Google Scholar
Watts, W. W. 1905. On the igneous rocks of the Welsh Border. Proceedings of the Geologists' Association 19, 173–83.CrossRefGoogle Scholar
Watts, W. W. 1925. The geology of south Shropshire. Proceedings of the Geologists' Association 36, 321–63.CrossRefGoogle Scholar
Whittard, W. F. 1979. An account of the Ordovician rocks of the Shelve Inlier in west Salop and part of north Powys. Bulletin of the British Museum (Natural History) Geology series 33 (1), 69 P.Google Scholar
Williams, A. 1974. Ordovician brachiopoda from the Shelve District, Shropshire. Bulletin of the British Museum (Natural History) Geology series, Supplement 11, 1–163.CrossRefGoogle Scholar