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Whole-rock Rb-Sr Isotopic Investigation of some East African Granulites*

Published online by Cambridge University Press:  01 May 2009

C. M. Spooner ,
J. V. Hepworth  and
H. W. Fairbairn
C. M. Spooner
Affiliation:
Department of Earth and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, U.S.A.
J. V. Hepworth
Affiliation:
Institute of Geological Sciences, 5 Princes Gate, London, S.W.7.
H. W. Fairbairn
Affiliation:
Department of Earth and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, U.S.A.
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Summary

Preliminary Rb-Sr whole-rock isotopic analyses of some East African granulites give the following ages and initial ratios:

The initial ratios, at the 0.705–0.706 level, conform with a world-wide pattern found for granulites and other deep crustal rocks. The whole-rock ages are the first such study on East African granulites. They confirm in West Nile the suspected early Pre-Cambrian age of the Uganda basement, and in Tanzania raise source rock problems which involve the Mozambique Front.

Type
Articles
Information
Geological Magazine , Volume 107 , Issue 6 , November 1970 , pp. 511 - 521
Copyright
Copyright © Cambridge University Press 1970

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Footnotes

*

M.I.T. Age Studies No.88

References

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