606 ISSN 0869-5911, Petrology, 2009, Vol. 17, No. 6, pp. 606–625. © Pleiades Publishing, Ltd., 2009. Original Russian Text © O.A. Bogatikov, V.A. Kononova, A.A. Nosova, A.V. Kargin, 2009, published in Petrologiya, 2009, Vol. 17, No. 6, pp. 651–671. INTRODUCTION During the past decades, new kimberlite provinces and pipes and new types of kimberlites have been dis- covered. In Russia, these are the new East European province (EEP) of kimberlites, which is characterized by wide variations in rock age (from the Proterozoic to the Devonian) and composition (Archangelsk Diamon- diferous…, 1999; Kononova et al., 2007; Bogatikov et al., 2007). In the Siberian craton (SC), kimberlite magmatism is confined mainly to Yakutia (Yakutian Diamondiferous Province, YDP), where new kimber- lite regions and fields were also discovered (e.g., Nakyn field). Their age ranged from the Middle Paleozoic to the Paleogene, and the composition of kimberlites was also variable (Golubeva et al., 2006; Kargin et al., 2008; etc.). The rare oldest (Proterozoic) occurrences of kim- berlite magmatism were found in the southwest of the SC (Ingashinskoe field). Until recently, the comparative analysis of the kimberlite magmatism of the EEP and SC was carried out only in a few studies, which focused mainly on the comparison of data on the geology, geo- morphology, and mineral composition of kimberlites (Khar’kiv, 1992; Milashev and Sokolova, 2000; etc.). In a recent fundamental study, Belov et al. (2008) did not pay adequate attention to the comparative analysis of the EEP and SC kimberlites. Another debatable topic is the composition of pri- mary kimberlite melt. The problem is related primarily to the fact that there are practically no rapidly quenched kimberlite lavas, and unfractionated kimberlites that are periodically described in the literature provide no compelling evidence for the retention of their primary composition. Kimberlite magmas are usually contami- nated by crustal materials, mantle xenoliths, and xenoc- rysts; in addition, they are strongly altered owing pri- marily to the serpentinization or saponitization of oliv- Polygenetic Sources of Kimberlites, Magma Composition, and Diamond Potential Exemplified by the East European and Siberian Cratons O. A. Bogatikov, V. A. Kononova, A. A. Nosova, and A. V. Kargin Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry (IGEM), Russian Academy of Sciences, Staromonetnyi per. 35, Moscow, 119017 Russia; e-mail: victoria@igem.ru Received July 15, 2009 Abstract—The petrological and geochemical characteristics of kimberlites from two Russian provinces of the northern East European craton (EEP) and the Siberian craton (SC) (especially the Yakutian diamondiferous province, YDP), and aphanitic kimberlites from the Jericho pipe (Canada) were compared for the elucidation of some aspects of the genesis of these rocks. The comparison of the EEP and YDP showed that they comprise identical rock associations with some variations in kimberlite composition between particular fields and regions, which are clearly manifested in the TiO 2 –K 2 O, TiO 2 –(Y, Zr, HREE), SiO 2 –MgO, SiO 2 –Al 2 O 3 , MgO– Ni, MgO–CO 2 , and MgO–H 2 O diagrams and in variations in light element ratios (Li/Yb, Be/Nd, and B/Nb). The compositions of YDP kimberlites are confined mainly to quadrant III; i.e., their source was mainly the depleted mantle, whereas the compositions of EEP kimberlites fall within all four quadrants in the fields of both enriched and slightly depleted mantle reservoirs. The initial ( 143 Nd/ 144 Nd) i ratio of kimberlites from the Yaku- tian collection is 0.5121–0.5126. The lead isotopic characteristics of the EEP and YDP kimberlites are similar to mantle values: 206 Pb/ 204 Pb of 16.19–19.14, 207 Pb/ 204 Pb of 15.44–15.61, and 208 Pb/ 204 Pb of 34.99–38.55. In the 207 Pb/ 204 Pb– 206 Pb/ 204 Pb diagram, part of the kimberlites, including those from the Botuobiya pipe, fall within the lower part of the field of group I kimberlites from southern Africa near the Pb isotopic composition of the depleted mantle. It was shown that the chemical compositions of the aphanitic kimberlites of the Jericho pipe (supposedly approaching the composition of primary magmas) are similar to those of some individual kim- berlite samples from the YDP and EEP. It was supposed that the initial kimberlite melt arrived from the astheno- sphere and was enriched in water and other volatile components (especially CO 2 ). During its ascent to the sur- face, the melt assimilated mantle components, primarily MgO; as a result, it acquired the compositional char- acteristics observed in kimberlites. Subsequent compositional modifications were related to diverse factors, including the type of mantle metasomatism, degree of melting, etc. We emphasized the importance of petrolog- ical and geochemical criteria (low contents of HREE and Ti in the rocks and a kimberlite source similar to BSE or EMI) for the estimation of the diamond potential of rocks. DOI: 10.1134/S0869591109060071