Nurali Ophiolite Massif (the Southern Urals): Geological, Structural, and Mineralogical Features

D. E. Saveliev, N. N. Ankusheva

Abstract


An overview of a geological structure of Nurali massif is presented. Compositional data of ultramafic rocks from mantle section and transitional mantle-crust assemblages, and chemistry of accessory and ore-forming Cr spinels are examined. We showed that ultramafic rocks from mantle section (spinel a spinel-plagioclase peridotites, harzburgites, dunites) are the tectonites. They have a strong predominantly optical orientation of rock-forming olivine due to a plastic flow of rocks. We presented different points of view on the mantle-crust assemblage origin, which composed by wehrlites, clinopyroxenites, vebsterites, dunites and melanocratic gneiss-like gabbro, and described two PGE-occurrences in the chromitites of this ophiolite section unit. This paper is based on a guidebook of an International field trip to Nurali massif as a part of conference “Magmatism of the Earth and related deposits of strategic metals” held in 2017 August

Keywords


ophiolite; ultramafic rocks; Cr spinels; PGE-minerals; Southern Urals; Nurali

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