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Volcanogenic quartz-magnetite-hematite veins, Snowdon, North Wales

Published online by Cambridge University Press:  05 July 2018

T. B. Colman  and
A.-K. Appleby
T. B. Colman
Affiliation:
Applied Geochemistry Group, British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K.
A.-K. Appleby
Affiliation:
Placer Pacific, 5-7 Eyre Street, Belmont 6104, Western Australia
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Abstract

In the Ordovician Snowdon Volcanic Group caldera quartz-magnetite-hematite-pyrite assemblages occur in a breccia vein in rhyolitic tuff and vein swarms in basalt. The veins developed pre-cleavage. Elevated levels of tin and tungsten in the veins, and of fluorine in the wall rocks, suggest a magmatic contribution to the mineralising fluids. The chemistry of the veins differs from that of the base-metal sulphide veins found elsewhere in the caldera.

Keywords

quartzmagnetitehematiteSnowdonWalesvolcanic rocks
Type
Petrology
Information
Mineralogical Magazine , Volume 55 , Issue 379 , June 1991 , pp. 257 - 262
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1991

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References

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