Features of the Geological Structure and Genesis of the Tebinbulak Deposit (Ridge Sultan-Uvais)

Abstract

In this article, we want to draw attention to the hysteron-magmatic origin of titanium-magnetite ores of the Tibinbulak gabbro-peridotite complex located in the northwestern part of the Sultan-Uvais ridge. Which is the only outlet of the Phanerozoic foundation between the mountain structures of the Urals and the Southern Tien Shan. The article examines the characteristic features of petrochemical and structural features of ore minerals (ilmenite, magnetite) and the main rock-forming minerals of the gabbro-peridotite complex (peridotite, pyroxenite, tebinnite, pyroxene hornblendite and plagioclase) with clarification of the structural relationships. It was found that magnetite mineralization of the Tebinbulak intrusion was superimposed on ultrabasic rocks in the final stages of crystallization of the latter. Prolonged auto-metasomatic transformations led to the enlargement of magnetite crystals in places subject to decay. In this case, aggregates of spinel - hercynite with sphene rims were formed. Simultaneously with the formation of sphene, ilmenite crystals appeared in the form of radiant needle-shaped aggregates. In this case, the primary crystals of magnetite lost their faces and became shapeless. Relatively large precipitates of titano-magnetite formed at this stage with the filling of cracks in the rock and interstices between minerals. Based on the data presented, we note that the titano-magnetite ores of the Tebinbulak deposit arose in the late magmatic (hysteron-geneous) setting of auto-metamorphic replacement of the main carriers of iron and titanium pyroxene and plagioclase with hornblende. Also, the studied geochemical composition of ores damages that the titano-magnetite ores of the Tebinbulak deposit are a complex raw material, from which not only iron but also vanadium concentrate can be extracted.