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The Phanerozoic cover sequences preserved as xenoliths in the kimberlite of eastern Sierra Leone

Published online by Cambridge University Press:  01 May 2009

F. H. Hubbard
F. H. Hubbard
Affiliation:
Department of Geology, The University, Dundee, DD1 4HN, Scotland
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Summary

Sedimentary and volcanic rocks, now unrepresented in surface exposure, occur as xenoliths in the kimberlite of the Koidu District of eastern Sierra Leone. The sedimentary rocks prove, on micropalaeontological evidence, to have Lower Palaeozoic stratigraphic age. An eastern extension of the Ordovician/Silurian marine transgression on to the Leo Uplift of the West African Craton of some 200 km is indicated. The volcanic rocks may belong to the same cycle of surface rock generation or relate to the younger, widespread, Triassic magmatic event.

Type
Articles
Information
Geological Magazine , Volume 120 , Issue 1 , January 1983 , pp. 67 - 71
Copyright
Copyright © Cambridge University Press 1983

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References

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