Similarities and Differences Between Kimberlite Rocks From the Northern Russian Platform and Other Regions

The paper describes the results of comparison of kimberlite rocks from the Russian Platform with similar formations from other regions. It has been stated that the kimberlite rocks from the northern Russian Platform have all major features of typical kimberlites. At the same time, there are some characteristics that distinguish them from an overwhelming majority of these rocks from other regions. The distinctive features are: a) relatively simple internal structure of pipes; b) high-magnesian composition of the rocks; c) low content of mineral indicators and their crystallization at a high oxidation potential; d) low content of deep-rock xenoliths and predominance of high-magnesian diaphorites; e) saponitization of kimberlites instead of usual serpentinization and carbonitization. These characteristics appear due to specific features of kimberlite melt formation under the upper mantle conditions and the kimberlite changes in the Earth crust.