Specific features of typification and diamondiferousness of kimberlites

Most of the studied kimberlite diatremes represent the multiphase pipes, where each magmatic phase of intrusion, formed inside diatremes, is composed by kimberlites of specific petrographic and petrochemical type characterized by the number of stable, slightly changing with depth typomorphic features. In the same diatreme, kimberlites of different intrusion phases differ in a correlation of porphyritic and clastic structural elements, and in a content of indicator minerals. Carried out studies indicated sufficient variation in diamondiferousness of different intrusion phases of kimberlites, which is controlled by different location depth and duration of the source magmatic pocket functioning, physical-chemical properties of initial components, as well as by velocity of ascent and character of kimberlite magma advance at the different kimberlite-formation stages. Kimberlite breccia of the completion stages of pipes formation are the most productive in comparison with porphyritic kimberlites of the early intrusion phases. For better assessing of the kimberlite pipes productivity, it is necessary to take into consideration the real relationship between the intrusive and explosive processes of kimberlite-formation, which usually vary in time.