(Нурали)
Ref.:
- Garuti, G. and Zaccarini, F., Cabella, R., and Fershtater, G. (1997) Occurrence of unknown Ru-Os-Ir-Fe oxides in the chromitites of the Nurali ultramafic complex, southern Urals, Russia. Canadian Mineralogist: 35: 1431-1439.
- Zaccarini F., Pushkarev E.V., Fershtater G.B., Garuti G. (2004) Composition and mineralogy of PGE-rich chromitites in the Nurali lherzolite-gabbro complex, Southern Urals,Russia, - Can. Miner., v.42, p.2, pp. 545-562.
An ultramafic complex in the Southern Urals.
The Nurali lherzolite–gabbro complex, in the Southern Urals, consists of mantle tectonite overlain by an ultramafic layered sequence, passing upward to amphibole gabbro and diorite.
(Upper mantle – deep crust transition zone below a continental margin).
Bodies of chromitite in the Nurali lherzolite–gabbro complex.are small concordant lenses within layered wehrlite and clinopyroxenite, overlying the lherzolitic mantle tectonite.
The ultramafic layered sequence hosting the chromitites formed by multistage intrusion and fractionation of hydrous magmas above a dominantly lherzolitic mantle tectonite.
One lens occurs within the wehrlite – clinopyroxenite – dunite – gabbro
cumulus sequence, above the contact with the dunite unit.
The other lens of chromitite is located inside a large ultramafic block isolated in the serpentinite mélange. The chromitite body consists of the rhythmic repetition of massive seams interlayered with wehrlite and clinopyroxenite.
