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Sapphirine-bearing granulitcs from Labwor, Uganda

Published online by Cambridge University Press:  05 July 2018

P. H. Nixon
Affiliation:
Dept. of Mines and Geology, Lesotho
A. J. Reedman
Affiliation:
Institute of Geological Sciences, London
L. K. Burns
Affiliation:
Dept. of Geology, Colorado State University

Summary

The structural setting of a refoliated belt of sapphirine granulites in northern Uganda and petrography of two selected rocks are described. Electron-probe analyses of the following minerals are given: ilmenite, titanian hematite, rutile, magnetite, sapphirine, hyperstheue, brown and green biotite, garnet, and cordierite. Field and experimental data suggest the following paragenesis: deposition of ferruginous shales with siliceous bands, followed by burial and regional metamorphism under granulite facies conditions, and finally rapid unloading associated with refoliation and shearing and crystallization of sapphirine and cordierite.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1973

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