Sr AND Nd ISOTOPIC COMPOSITIONS OF KIMBERLITES AND ASSOCIATED ROCKS OF THE SIBERIAN CRATON

Abstract

Recent revision of the classification of kimberlite rocks and associated rocks made it possible to propose a modern classification that includes two natural formation series (hereafter, series) with different features. The first series includes traditional rock associations of platformal alkali ultramafic magmatism: diamondiferous kimberlites, picrite–alnoite rocks associated with rare-metal carbonatite complexes (alpicrites), and a large group of alkali picrites (kimpicrites) that occupy an intermediate position between the two series and lack any distinct metallogenic specifics. The second series includes diamondiferous olivine lamproites, orangeites, and majhgawanites.