The first find of spinel peridotite in the Southern Kazakhstan: Structure, composition, and parameters of high-pressure metamorphism

Spinel peridotite, metamorphosed in high-pressure conditions, was first described within the Western part of the Central Asian Orogenic Belt. The spinel peridotite has the characteristics of Mg–Cr ultramafites indicating the mantle origin of its protolith. The preliminary estimation of the metamorphism peak for the model system MgO–Al2O3—SiO2–Cr2O3 (MASCr) is 10–19 kbar at 680–800°C.