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K–Ar and Rb–Sr isotopic age studies on the Wolf Rock nosean phonolite, Cornwall

Published online by Cambridge University Press:  01 May 2009

J. G. Mitchell ,
R. M. Macintyre  and
I. R. Pringle
J. G. Mitchell
Affiliation:
School of PhysicsThe UniversityNewcastle upon Tyne
R. M. Macintyre
Affiliation:
Isotope Geology UnitScottish Research and Reactor CentreEast Kilbride
I. R. Pringle
Affiliation:
Department of Geodesy and GeophysicsThe University of Cambridge
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Summary

Potassium–argon and rubidium–strontium isotopic age studies of the Wolf Rock phonolite of SW England confirm its age as 131 Ma, with an initial 87Sr/88Sr ratio of 0.703. The existence of a Mesozoic volcanic province of this age on the margin of the Labrador–Biscay rift is discussed with special reference to its implications for the early evolution of the N.Atlantic Ocean, and the general relationship of alkaline igneous activity to major periods of plate reorientation.

Type
Articles
Information
Geological Magazine , Volume 112 , Issue 1 , January 1975 , pp. 55 - 61
Copyright
Copyright © Cambridge University Press 1975

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