The Nature of Grain Boundaries in Dunite from Zoned Complexes of the Urals

摘要

Zoned dunite-clinopyroxenite complexes of the Alaska (Ural-Alaska) type [1 and others] have attracted the attention of researchers by the unusual peculiarities of the structure, composition, and native chromium-platinum mineralization for more than one hundred years. The structure of massifs of the Pla-tiniferous Belt of the Urals is determined by the presence of a small (a few kilometers) dunite core surrounded by a relatively thin clinopyroxenite envelope; gabbroids are absent or have dependent importance [2-4]. Currently the origin of these formations is debatable.