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A Suspected Spilitic Rock from the Lower Cambrian Manganese Shale Group of the Harlech Dome, North Wales

Published online by Cambridge University Press:  01 May 2009

P. A. Mohr
P. A. Mohr
Affiliation:
Geophysical Observatory, Addis Ababa, Ethiopia.
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Abstract

Mineral and chemical evidence suggest that an unusual rock from the Upper Manganese Shales of Diphwys is of spilitic origin, despite certain geochemical anomalies. Some similarities of the rock to the shales themselves are only superficial, and a metasomatic origin is precluded; the rock is also very distinct from the “greenstone” sills of the region.

Type
Articles
Information
Geological Magazine , Volume 99 , Issue 3 , June 1962 , pp. 265 - 272
Copyright
Copyright © Cambridge University Press 1962

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References

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