ENDOGENOUS DIAMOND FORMATION IN THE UKRAINIAN SHIELD

Abstract

A theoretical model is proposed for diamond formation in the crust of the Ukrainian Shield. The temperatures required for the formation of diamonds are sustained by overheated magmatic material of mantle diapirs (identified in the crust of the Ukrainian Shield by deep geophysical methods). The required pressure is sustaned in local units (cells) of mantle diapirs by thermoactive dissociation (up to the gaseous form) of xenogenic crustal material. The crustal material must contain hydrocarbons. The pressure built up inside a cell is seven times higher than the lithostatic pressure, which ensures explosive transportation of diamonds through diatremes (explosion pipes). Potentially diamond-bearing areas in the ukrainian Sheild are: Volyn, Kirovograd and Cis-Azov arkhons, Korsun-Novomyrgorod tectons and Vinnitsa proton.