www.elsevier.com/locate/rgg Relationship between platinum-bearing ultramafic–mafic intrusions and large igneous provinces (exemplified by the Siberian Craton) A.S. Mekhonoshin a,b, * , R. Ernst c,d , U. Söderlund e , M.A. Hamilton f , T.B. Kolotilina a,b , A.E. Izokh g,h , G.V. Polyakov g , N.D. Tolstykh g a Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, ul. Favorskogo 1a, Irkutsk, 664033, Russia b Irkutsk Research Technical University, ul. Lermontova 83, Irkutsk, 664074, Russia c Department of Earth Sciences, Carleton University, Ottawa, ON K1S 5B6, Canada d Tomsk State University, ul. Lenina 36, Tomsk, 634050, Russia e Lund University, 12 Sulvegatan, Lund, 223 62, Sweden f J. Sutterlay Geochronology Laboratory, Toronto University, Toronto, ON N5S 3B1, Canada g V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia h Novosibirsk State University, ul. Pirogova 2, Novosibirsk, 630090, Russia Received 8 July 2015; accepted 24 September 2015 Abstract This study aims at summarizing available geological and geochemical data on known Proterozoic platinum-bearing ultramafic-mafic massifs in the south of Siberia. Considering new data on geochemistry and geochronology of some intrusions, it was feasible to compare ore-bearing complexes of different time spans and areas and to follow their relationships with the recognized large igneous provinces. In the south of Siberia, the platinum-bearing massifs might be united into three age groups: Late Paleoproterozoic (e.g., Chiney complex, Malozadoisky massif), Late Mesoproterozoic (e.g., Srednecheremshansky massif), and Neoproterozoic (e.g., Kingash complex, Yoko-Dovyren massif, and massifs in the center of the East Sayan Mts.). In most massifs but Chiney the initial magmas are magnesium-rich. On paleogeodynamic reconstructions, the position of the studied massifs is the evidence that three most precisely dated events in North Canada continued into southern Siberia: In the period 1880–1865 Ma, it was the Ghost–Mara River–Morel LIP; at 1270–1260 Ma, the Mackenzie LIP; and at 725–720 Ma, Franklin LIP. In Siberia, the mostly productive massifs with respect to PGE–Ni–Cu mineralization are those linked with the Franklin LIP: Verkhny Kingash, Yoko-Dovyren, and central part of the Eastern Sayan Mountains, e.g., Tartay, Zhelos, and Tokty-Oy. © 2016, V.S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserved. Keywords: PGE–Ni–Cu deposits; mafic-ultramafic intrusions; large igneous provinces Introduction As regards the economic value, magmatic PGE–Ni–Cu deposits typify: (1) sulfide PGE–Ni–Cu and (2) low-sulfide Pt–Pd (Ernst, 2014; Maier, 2005; Naldrett, 1981). Formation of sulfide PGE–Ni–Cu deposits is largely due to separation of sulfide melt rich in chalcophyle elements and PGE from basic or ultrabasic magma. In the works (Naldrett, 2010a,b) Naldrett recognized seven types of PGE–Ni–Cu deposits, and in four deposits magma formation is linked with LIPs (Ernst and Jowitt, 2013). They are referred to magmatic sulfide deposits associated with Archean and Proterozoic komatiites, trap magmatism, derivatives of ferropicritic magmas and diverse magmas of picritic and tholeiitic composition. The best instances are unique deposits of Norilsk group (250 Ma Siberian trap LIP) (Lightfoot and Keays, 2005; Mitrofanov et al., 2013; etc.), PGE–Ni–Cu deposits in China (Permian Eimeshan plume) (Borisenko et al., 2006). The Pt–Pd-bearing deposits commonly sit within layered mafic-ultramafic intrusions (Eckstrand and Hulbert, 2007; Naldrett, 2003), their formation associated with two types of magmas (Naldrett, 2010a). High abundances of Ni, Cu, Co, Cr, V, PGE in basic and ultrabasic magmas result from enrichment with these elements of magma-generating mantle substrates, which is related to deep mantle plumes emplaced on the core-mantle boundary (Dobretsov et al., 2010; Kuzmin and Yarmolyuk, 2014; Pirajno and Santosh, 2014). It is Russian Geology and Geophysics 57 (2016) 822–833 * Corresponding author. E-mail address: mekhonos@igc.irk.ru (A.S. Mekhonoshin) Available online at www.sciencedirect.com ScienceDirect ed. 1068-7971/$ - see front matter D 201 IGM, Siberian Branch of the RAS. Published by Elsevier B.V. All rights reserv V.S. S bolev o http://dx.doi.org/10.1016/j.rgg.201 .0 .0 6, 5 9 20