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Petrology and geothermometry of the Little Michiru Complex, Malawi

Published online by Cambridge University Press:  05 July 2018

S. W. Morel
S. W. Morel*
Affiliation:
Granary Farm, Chitcombe Road, Broad Oak, E. Sussex TN31 6EU
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Abstract

The Little Michiru complex is a composite intrusion of pyroxenite and pyroxene syenite which is located at the boundary between amphibolite and granulite facies gneisses in the Shire rift valley. Pyroxene and feldspar chemistry shows that the intrusion consolidated from two magmatic fractions, one a pyroxenite cumulate that equilibrated at 870–1000 °C, the other a partly anatectic pyroxene syenite magma which metasomatized the surrounding gneisses during granulite-facies metamorphism and equilibrated at a temperature of 730–830 °C at 7 kbar.

Keywords

pyroxenitepyroxene syenitepetrologygeothermometryLittle Michiru complexMalawi

Information

Type
Petrology and Geochemistry
Information
Mineralogical Magazine , Volume 53 , Issue 371 , June 1989 , pp. 285 - 291
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

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