UNUSUAL KIMBERLITE MAGMATISM IN THE NORTHEAST OF THE SIBERIAN PLATFORM

Kimberlite indicator minerals (KIMs) from the watershed of the Kyra-Razboinik River (tributary of the Olenyok) are of two groups distinguished according to morphology: (i) minerals derived directly from weathered primary kimberlite deposits known in the area and (ii) placer minerals redeposited from older host formations. Compositions for both groups of pyrope are characteristic of Jurassic-Cretaceous age kimberlites. This indicates that already in the Middle Paleozoic, deep metasomatosis in some areas is similar to Mesozoic metasomatosis.