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Porphyroblastic and Augen Gneisses in the Bartica Assemblage, British Guiana

Published online by Cambridge University Press:  01 May 2009

R. T. Cannon
Affiliation:
Geological Survey Department, P.O. Box 789, Georgetown, British Guiana.

Abstract

Textural differences in the occurrence of microcline define augen gneisses, subhedral porphyroblastic gneisses and euhedral porphyroblastic gneisses within the Bartica Assemblage, British Guiana. The introduction of microcline is metasomatic and the nature of the porphyroblasts appears to be a reflection of tectonic control during their development.

Type
Articles
Copyright
Copyright © Cambridge University Press 1964

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References

REFERENCES

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