CARBONATITES OF THE TURIY PENINSULA, KOLA: ROLE OF MAGMATISM AND OF METASOMATISM

ANDREI G. BULAKH
Departments of Mineralogy, St. Petersburg University, 7/9 University Emb., St. Petersburg, Russia 199034

VALERIY V. IVANIKOV
Department of Petrology, St. Petersburg University, 7/9 University Emb., St. Petersburg, Russia 199034

Abstract

Two types of carbonatite occur on the Turiy Peninsula (Kola District, Russia); it forms dykes and a stock-like body within an alkaline-ultramafic massif. Chemical data indicate that samples of olivine melanephelinite are generally close to the composition of the initial melts. The main processes are fractional crystallization accompanied by accumulation and liquid immiscibility. Early (magmatic) carbonates are easily modified by metasomatic hydrothermal alteration.