About specific features of diamonds from kimberlites and ancient sedimentary thick layers (on the example of Central-Siberian sub-province)

Abstract

Diamonds from half-industrial diatremes of Daldyn-Alakitsky and Verkhne-Munsky diamondif-erous regions are characterized by prevalence of rhombic dodecahedral habit crystals at high content of typical rounded diamonds, being unfavorable factor of diamondiferousness. Difference in diamond features of individual kimberlite bodies is less than within diamondiferous regions against each other on the whole, which serves as confirmation of upper mantle structure heterogeneity in various parts of the platform. Prevalence of laminar crystals of octahedral, rhombic dodecahedral and transitive between them habits in pipes of peripheral part of the Siberian platform (pipe Malo-Kuonapskaya) is indicative of horizontal zonality absence in alteration of typomorphic features within the investigated territory. Typo-morphic features of diamonds of the Siberian platform perspective territories are adduced and possibility to use them when forecasting primary deposits is shown at the stages of regional, average-scale, as well as local forecasting. Results of complex investigation of a number of kimberlite bodies with half-industrial diamondiferousness of individual regions of the Siberian platform are provided, which allowed establishing typomorphic features of the mineralю. Examples of using typomorphic features of diamonds are shown for forecasting high-diamondiferous kimberlites within Central-Siberian (Malobotuobinsky, Daldyn-Alakitsky, Morkoka and Sredne-Markhinsky regions).