High fO2 metasomatism during whiteschist metamorphism, Zambezi Belt, northern Zimbabwe.

SP Johnson, Grahame John Henderson Oliver

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)

Abstract

The Kodurguri Whiteschists are a group of talc- and kyanite-bearing lithologies that occur in the Chewore Inliers from the Zambezi Belt of northern Zimbabwe. They crop out on the southern margin of the Chewore Ophiolite Terrane, a Mesoproterozoic ophiolite and island arc, as a 5 km x 1.5 km, southeasterly dipping, semi-continuous block, and contain the second known natural occurrence of yoderite. Major element analyses define the whiteschists within the relatively simple MFASH system. Major and trace element analyses indicate that the whiteschists originate from the metasomatic alteration of alkalic ocean-island-ope metabasalts similar to those in the underlying Ophiolite Terrane. Synmetamorphic or metasomatic mineral parageneses indicate peak P-T conditions of between 13 and 15 kbar at 550-600degreesC, and the highly oxidizing nature of all reactions indicates the presence of a high fO(2) metasomatic fluid. The peak P-T conditions require that this synmetamorphic, exotic metasomatic fluid was available at depths near 55 km., The age of high-pressure metamorphism is constrained within the Pan African tectonothermal cycle at 550-520 Ma. Tectonometamorphism,in the Zambezi Belt is related to a period of extensive crustal thickening possibly, related to amalgamation of Gondwanaland.

Original languageEnglish
Pages (from-to)271-290
Number of pages20
JournalJournal of Petrology
Volume43
Issue number2
DOIs
Publication statusPublished - Feb 2002

Keywords

  • Congo Craton
  • high pressure
  • Kalahari Craton
  • metasomatism
  • whiteschist
  • Zambezi Belt
  • CHEWORE-INLIERS
  • PAN-AFRICAN
  • SYSTEM MGO-AL2O3-SIO2-H2O
  • KOKCHETAV MASSIF
  • SOUTHERN AFRICA
  • EVOLUTION
  • PRESSURE
  • ZAMBIA
  • YODERITE
  • BEARING

Fingerprint

Dive into the research topics of 'High fO2 metasomatism during whiteschist metamorphism, Zambezi Belt, northern Zimbabwe.'. Together they form a unique fingerprint.

Cite this