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The composition and age of basalts dredged from the Blackstones igneous centre, western Scotland

Published online by Cambridge University Press:  01 May 2009

J. G. Mitchell ,
E. J. W. Jones  and
G. T. Jones
J. G. Mitchell
Affiliation:
School of Physics, The University, Newcastle-upon-Tyne, NE1 7RU
E. J. W. Jones
Affiliation:
Department of Geology, University College, Gower Street, London WC1E 6BT
G. T. Jones
Affiliation:
Department of Geology, University College, Gower Street, London WC1E 6BT
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Summary

A collection of basaltic rocks has been dredged from part of the Blackstones igneous centre, a major offshore intrusion situated about 50 km SW of Mull. The basalts are mainly olivine tholeiites and are closely similar to transitional basalts found on the Inner Hebrides. The mean of four concordant K—Ar dates obtained from the lavas indicates an age of 57.1 (± 0.9) Ma. The Blackstones complex thus appears to be coeval with other Tertiary centres of the area.

Type
Articles
Information
Geological Magazine , Volume 113 , Issue 6 , November 1976 , pp. 525 - 533
Copyright
Copyright © Cambridge University Press 1976

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