The origin of dunites and olivinites in the alkali-ultrabasic intrusive complexes of the Siberian Craton

The factual evidence and the evidence of experimental studies support a cumulative origin of dunites from alkali-ultrabasic complexes of the Siberian Craton (Guli, Kondyor, Inagli, and others). These rocks formed during deep igneous evolution of melts that are close to biotite-pyroxene alkali picrite (meimechite). Olivinites that sometimes compose completely or in part the particular massifs (Bor-Yuryakh, Odikhincha, Kugda, and others) formed, in turn, due to recrystallization of dunites under the effect of alkali melts and fluids. This insight into the origin of dunites and olivines from these intrusive complexes requires an objective assessment of their ore-bearing potential.     

Nature of the ultramafite–mafite complex of the Guli Pluton (Polar Siberia)

Comparative analysis of the composition and formation conditions of the dunite–pyroxenite association of the Guli Pluton and ultramafic vulcanite (meimechite) showed the similarity of their initial melts and the same type of crystallization, demonstrating the cumulative origin of dunite.