Mineral chemistry and petrogenesis of Galvans chromitites, eastern metamorphic complex of Khoy ophiolite

Document Type : Research Paper

Authors

Abstract

In the eastern metamorphic complex of Khoy ophiolite, several chromitite lenses are exposed which some of them are exploited. Chromitites of Galvans area have been surveyed recently during exploration activities. There are two mineralization zones which are 150 meters apart other. The Zone 1 mineralization has chromites with banded textures and enclosed by dunitic host rock. The Zone 2 mineralization is a large lens composed of massive texture chromites. Both of them enclosed by mantle peridotites. Mineral chemistry studies on zone 2 chromites (chromitites) indicate that they have average Cr# and Mg# 40.90 and 77.45 respectively and are podiform, Alpine type with high Al2O3 content. Based on tectonic setting discrimination diagrams, these chromites (zone 2) were formed in the MORB setting. Parental melt chemistry calculation of these chromites (zone 2) demonstrates that it has Al2O3 (16.98-17.16 wt %) content and FeO/MgO (0.79-0.83) ratios. These features are consistent with Al2O3 content and FeO/MgO ratio of MORB-type melt.

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References

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History

  • Receive Date: 09 April 2015
  • Revise Date: 18 August 2016
  • Accept Date: 13 October 2015

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