Sapphirine-Bearing Granulites from Labwor, Uganda

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

Mineralogical Magazine; December 1973 v. 39; no. 304; p. 420-428; DOI: 10.1180/minmag.1973.039.304.05
© 1973, The Mineralogical Society
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