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On the mechanism of formation of reduction spots in the carboniferous/permian red beds of Warwickshire

Published online by Cambridge University Press:  01 May 2009

H. Mykura  and
B. P. Hampton
H. Mykura
Affiliation:
Physics Department, University of Warwick, Coventry CV4 7AL
B. P. Hampton
Affiliation:
Physics Department, University of Warwick, Coventry CV4 7AL
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Extract

Measurements of the size and shape of the grey reduction spots and of the variation of iron content across the spot–host rock interface have been made on samples from the Enville Group. The red coloration due to Fe3+ is thought to reside mainly in the matrix material cementing the mineral grains of the rock. The reduction to Fe2+ is ascribed to carbonaceous particles included in the sediment. To account for the sharp boundary of the spots it is suggested that the outward movement of the boundary is due to concentration dependent inward diffusion of oxygen which converts the carbonaceous material to carbonate.

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Articles
Information
Geological Magazine , Volume 121 , Issue 1 , January 1984 , pp. 71 - 74
Copyright
Copyright © Cambridge University Press 1984

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References

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