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The Hangnest Dolerite Sill, S.A

Published online by Cambridge University Press:  01 May 2009

F. Walker
Affiliation:
Department of Mineralogy and Geology, University of Cape Town
A. Poldervaart
Affiliation:
Department of Mineralogy and Geology, University of Cape Town

Extract

A 500 ft. sill of dolerite from Hangnest in the Calvinia division of the Cape Province (South Africa) exemplifies very clearly two well-marked features of the thicker Karroo sills:—

(1) Very slight amount of crystallization-differentiation.

(2) Marked tendency to mobilize and react with the associated shales and siltstones.

A petrological and chemical study of this sill is given and the mechanism of the various processes discussed.

Type
Articles
Copyright
Copyright © Cambridge University Press 1941

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References

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