TY - JOUR

T1 - Distribution of sulfides and PGE minerals in the picritic and taxitic gabbro-dolerites of the Norilsk 1 intrusion

AU - Tolstykh, Nadezhda

AU - Garcia, Jonathan

AU - Shvedov, Gennadiy

N1 - Funding Information: We thank Aleksandr Polonyankin, the deputy of General Director of Russian Platinum LLC, for the opportunity to examine ore samples. We are grateful to the Norilsk geologists for their brave work in the exploration of the subsoil and for providing unique factual material for research, to P.N. Samorodsky, Associate Professor of the Department of Geology of Deposits and Methods of Exploration, Institute of Mining, Geology and Geotechnology, Siberian Federal University (Krasnoyarsk), and also VN Korolyuk for testing WDS and EDS analyzes of sulfides and PGMs, as well as NB Belkina (IGM SB RAS) for technical assistance in preparing the manuscript. The work was done with financial support of the Grant of the Ministry of Science and Higher Education of the Russian Federation No. 13.1902.21.0018 ‘‘Fundamental development problems in mineral resource base high-tech industry and power engineering of Russia’’. Publisher Copyright: © 2021 Mineralogical Association of Canada. All rights reserved.

PY - 2021/11

Y1 - 2021/11

N2 - Disseminated ores in the Norilsk 1 intrusion were studied to elucidate the typomorphic features of sulfides and noble metal mineralizations in picritic and taxitic (or lower olivine) gabbro-dolerites. The former are characterized by the development of a low-sulfur sulfide association (troilite, Fe-rich pentlandite, talnakhite, chalcocite, native copper) while the latter exhibits a high-sulfur association (monoclinic pyrrhotite, Ni-rich pentlandite, pyrite, heazlewoodite). The contact between these types of rocks is geochemically and mineralogically contrasting. The mineralogical and geochemical zoning directed from the roof to the base of each layer is expressed by an increase in the Cu content (and chalcopyrite) in ores, an increase in the concentration of Ni in pentlandite and S in pyrrhotite in line with a decrease of the crystallization temperature, and an increase in sulfur fugacity in the same direction. Zoning of Pd(Pt) mineralization in picritic and taxitic (olivine) gabbro-dolerites is uniform and characterized by the distribution of Pd-Sn compounds in the upper parts (together with Pd-Pb minerals in picritic rocks) and Pd-As compounds in the lower parts of the sections according to a drop in temperature. Such reverse zoning contradicts the typical mechanism of differentiation by fractional crystallization, and possibly suggests a fluid-magmatic nature. Mineralogical and geochemical features in platinum group element-Cu-Ni-bearing rocks are consistent with the idea that different stages of multi-pulse intrusions of mafic-ultramafic magmas with different compositions formed the picritic and taxitic gabbro-dolerites of the Norilsk region.

AB - Disseminated ores in the Norilsk 1 intrusion were studied to elucidate the typomorphic features of sulfides and noble metal mineralizations in picritic and taxitic (or lower olivine) gabbro-dolerites. The former are characterized by the development of a low-sulfur sulfide association (troilite, Fe-rich pentlandite, talnakhite, chalcocite, native copper) while the latter exhibits a high-sulfur association (monoclinic pyrrhotite, Ni-rich pentlandite, pyrite, heazlewoodite). The contact between these types of rocks is geochemically and mineralogically contrasting. The mineralogical and geochemical zoning directed from the roof to the base of each layer is expressed by an increase in the Cu content (and chalcopyrite) in ores, an increase in the concentration of Ni in pentlandite and S in pyrrhotite in line with a decrease of the crystallization temperature, and an increase in sulfur fugacity in the same direction. Zoning of Pd(Pt) mineralization in picritic and taxitic (olivine) gabbro-dolerites is uniform and characterized by the distribution of Pd-Sn compounds in the upper parts (together with Pd-Pb minerals in picritic rocks) and Pd-As compounds in the lower parts of the sections according to a drop in temperature. Such reverse zoning contradicts the typical mechanism of differentiation by fractional crystallization, and possibly suggests a fluid-magmatic nature. Mineralogical and geochemical features in platinum group element-Cu-Ni-bearing rocks are consistent with the idea that different stages of multi-pulse intrusions of mafic-ultramafic magmas with different compositions formed the picritic and taxitic gabbro-dolerites of the Norilsk region.

KW - Disseminated sulfide

KW - Gabbro-dolerite

KW - Norilsk 1 intrusion

KW - PGE minerals

KW - Picritic

KW - Taxitic

KW - Zoning

UR - http://www.scopus.com/inward/record.url?scp=85122123926&partnerID=8YFLogxK

UR - https://www.elibrary.ru/item.asp?id=47551893

U2 - 10.3749/CANMIN.2100037

DO - 10.3749/CANMIN.2100037

M3 - Article

AN - SCOPUS:85122123926

VL - 59

SP - 1437

EP - 1451

JO - Canadian Mineralogist

JF - Canadian Mineralogist

SN - 0008-4476

IS - 6

M1 - 1

ER -