EVIDENCE OF KIMBERLITE MAGMATISM IN THE NORTHERN PART OF THE EAST EUROPEAN CRATON

Abstract

Diamond-bearing kimberlites have so far been found almost entirely on cratons. In this respect, the East European epi-Karelian craton is still considered to have little potential. Nevertheless, besides placer deposits of diamonds in the Urals, the Ukraine and elsewhere, the favorable potential of this craton for bedrock diamonds is indicated by finds of kimberlite bodies in the central Timan and in the area east of the White Sea. Having reinterpreted magnetic anomalies from data of 1:2000,000-scale aeromagnetic surveys, we were able to identify some distinctive structures, clearly reflected in the magnetic field. More than 300 such contrasting anomaly-generating bodies were identified. Comparative analysis of some of the anomalies brought out with the physical fields of known kimberlite bodies revealed their definite similarity. We conclude that the paleogeodynamic situation in the northern part of the East European craton was favorable for kimberlite magmatism, as confirmed both by direct finds of kimberlite bodies here and by analysis of geophysical data.