LESS-COMMON AND RARE EARTH ELEMENTS OF THE PECHENGA REGION ORES

The article presents the investigations in the Pechenga ore region — one of the largest industrial regions in the Arctic zone of Russia, located on the territory of the Murmansk area. The researchers obtained new data on the chemical composition of the main ore minerals, the content of trace elements, including rare earths (REE), in the ores of the Pilguyarvi and Vostok deposits and late polymetallic veins of the Pechenga region. They found that the main textural types of ores (massive, veined and disseminated) differ significantly in chemical composition and content of rock and ore-forming components. They also revealed the enrichment of ores with a wide range of trace elements. In comparison with the upper crust, the Pechenga ores are clearly enriched with chalcophilic and siderophilic trace elements. The enrichment coefficients of ore elements reach mainly tens (Cr, Au, Cd) hundreds (Ag, Se, Re, Pt) and thousands (Ni, Cu, Ir) times. The distribution of trace elements in various types of Cu-Ni ores has a great similarity, which indicates their geochemical affinity and synchronous participation in ore formation. The geochemical features are in good agreement with the mineral composition of the ores. The concentration of rare earth elements in the main types of ores, with the exception of massive ores and late polymetallic veins, exceeds the level of the chondrite standard and the REE fractionation is weak. The composition of the REE in ores came by from the host rocks. The research has established the high enrichment of all types of Re, Bi and Cd ores, which are potentially industrially significant as high-tech metals and are of considerable interest for associated mining.

1. Gorbunov G. I. Mineralogy of copper-nickel deposits of the Kola Peninsula. St. Petersburg, Science, 1981, 345 p. (In Russian).
2. Distler V. V., Filimonova A. A., Grokhovskaya T. L. et al. Platinum metals in copper-nickel ores of the Pechenga ore field. Geologiya rudnykh mestorozhdenii, 1998, vol. 31, no. 6, pp. 3—17. (In Russian).
3. Gorbunov G. N., Astaf’ev Yu. A., Goncharov Yu. V. et al. Copper-nickel deposits of the Pechenga. Otv. red. N. P. Laverov. Moscow, GEOS, 1999, 236 p. (In Russian).
4. Zak S. I., Kochnev-Pervukhov V. I., Proskuryakov V. V. Ultrabasic rocks of the Allarechensky district, their metamorphism and mineralization. Petrozavodsk, Karelia, 1972, 129 p. (In Russian).
5. Naldrett A. J. Magmatic sulfide deposits of copper-nickel and platinum-metal ores. — St. Petersburg, St. Petersburg State University, 2003, 487 p. (In Russian).
6. Smolkin V. F. Komatiite and picrite magmatism of the early Precambrian of the Baltic shield. St. Petersburg, Science, 1992, 278 p. (In Russian).
7. Bortnikov N. S., Volkov A. V., Galyamov A. L. et al. Mineral Resources of High_tech Metals in Russia: State of the Art and Outlook. Geology of Ore Deposits, 2016, vol. 58, no. 2, pp. 83—103. DOI: 10.1134/S1075701516020021.
8. Kazanskii V. I., Kuznetsov O. L., Kuznetsov A. V. et al. Deep structure and geodynamics of the Pechenga ore district: the experience of study of the Kola superdeep borehole. Geologiya rud. mestorozhdenii, 1994, vol. 36, no. 6, pp. 500—519. (In Russian).
9. Lobanov K. V., Chicherov M. V., Chizhova I. A. et al. Depth structure and oreforming systems of the Pechenga ore region (Russian Arctic Zone). Arktika: ekologiya i ekonomika. [Arctic: Ecology and Economy], 2019, no. 3 (35), рр. 107—122. DOI: 10.25283/2223-4594-2019-3-107-122. (In Russian).
10. King H. E., Prewitt C. T. High-pressure and high-temperature polymorphism of iron sulfides (FeS) // Acta Crystallographica, 1982, vol. 38, рр. 1877—1887.
11. Taylor S. R., McLennan S. M. Continental crust: its composition and evolution. Moscow, Mir, 1988, 384 p. (In Russian).
12. McDonough W. F., Sun S. S. The Composition of the Earth. Chemical Geology, 1995, vol. 120, рр. 223—253.
13. Grigorieva A. V., Volkov A. V., Murashov K. Yu. Rare-earth elements in Cu-Ni ores of the Norilsk region. Arktika: ekologiya i ekonomika. [Arctic: Ecology and Economy], 2021, vol. 11, no. 1, рр. 76—89. DOI: 10.25283/2223-4594-2021-1-76-89. (In Russian).