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MINERAL GEOLOGY AND EXPLORATION
ArticleName Geology and gold content of carbonaceous shale in Baikal mineralization site, Southern Ural
DOI 10.17580/em.2021.01.02
ArticleAuthor Snachev A. V., Kolomoets A. V., Rassomakhin M. A., Snachev V. I.
ArticleAuthorData

Institute of Geology, Ufa Federal Research Center, Russian Academy of Sciences, Ufa, Russia:

Snachev A. V., Head of Laboratory, Candidate of Geologo-Mineralogical Sciences, SAVant@rambler.ru

Snachev V. I., Professor, Doctor of Geologo-Mineralogical Sciences

 

Orenburg State University, Orenburg, Russia:
Kolomoets A. V., Senior Lecturer

 

South Urals Federal Research Center of Mineralogy and Geoecology, Russian Academy of Sciences, Miass, Russia:

Rassomakhin M. A., Junior Researcher

Abstract

The authors analyze gold mineralization in Baikal site inside Kumak ore field, adjoined to Bredin black shale sediments (С1bd). It is found that the gold mineralization within the site adjoins mostly bands of quart–micaceous–tourmaline metasomatically altered carbonaceous shale. Float sampling of all local rock varieties shows commercial content of gold (to 6.5 g/t) and stable high content of silver (to 7.6 g/t). Gold is mostly finely dispersed, and is connected with two basic mineral associations: gold–bismuth–telluride and native gold intergrown with tourmaline. The analysis of compositions of gold particles reveals their high carat type. Chemically, tourmaline belongs to dravite and foitite, and is similar to tourmaline from the deposits of orogenic gold and goldbearing sulfide ores. Tight accretion of fine needle-like tourmaline and gold implies their synchronous formation, and allows assessing Baikal site as the quartz–tourmaline gold ore formation.

The study was carried out under State Contract Topic No. 0246-2019-0078, the microprobe analyses were performed under State-Financed Topic No. AAAA-A19-119072390050-9 and were supported by Orenburgneft JSC in the framework of a corporate grant, 2019–2020.
The authors are extremely grateful to S. A. Yagudina, T. I. Chernikova and I. V. Smoleva for the analysis execution, to E. O. Kalistratova for the help in heavy concentrate description, as well as to R. S. Kisil and V. S. Panteleev for the assistance in field works.

keywords Southern Ural, Kumak ore field, Baikal ore site, carbonaceous shale, black shale, noble metals, gold, silver, telluride, tourmaline
References

1. Groves D. I., Goldfarb R. J., Robert F., Hart C. J. R. Gold Deposits in Metamorphic Belts: Overview of Current Understanding, Outstanding Problems, Future Research, and Exploration Significance. Economic Geology. 2003. Vol. 98, No. 1. pp. 1–29.
2. Arifulov Ch. Kh. Black shale gold deposits of various geological conditions. Ores and metals. 2005. No. 2. pp. 9–19.
3. Large R. R., Bull S. W., Maslennikov V. V. A carbonaceous sedimentary source-rock model for carlin type and orogenic gold deposits. Economic Geology. 2011. Vol. 106, No. 3. pp. 331–358.
4. Shumilova T. G., Shevchuk S. S., Isayenko S. I. Metal concentrations and carbonaceous matter in the black shale type rocks of the Urals. Doklady Earth Sciences. 2016. Vol. 469, No. 1. pp. 695–698.
5. Ivanov A. I. The role played by metamorphic transformation conditions of carbonaceous carbonate-terrigene deposits for gold mineralization formation at various stages of collisional epoch of Baikal-patom metallogenic province development. Otechestvennaya geologiya. 2017. No. 4. pp. 3–23.
6. Majumdar S., Singh S., Sahoo P. R. Characterization of organic matter and its implications for pyrite hosted refractory gold mineralization along the South Purulia Shear Zone, eastern India. Ore Geology Reviews. 2020. Vol. 124.103584. DOI: 10.1016/j.oregeorev. 2020.103584
7. Znamensky S. E., Znamenskaya N. M. Classification of gold deposits of the eastern slope of the Southern Urals. Geological collection. 2009. No. 8. pp. 177–186.
8. Snachev A. V., Puchkov V. N. First findings of palladium-gold-REE ore mineralization in precambrian carbonaceous shales on the western slope of the Southern Urals. Doklady Earth Sciences. 2010. Vol. 433, No. 1. pp. 866–869. DOI: 10.1134/S1028334X10070044
9. Gadd M. G., Peter J. M., Jackson S. E., Zhaoping Yang, Petts D. Platinum, Pd, Mo, Au and Re deportment in hyperenriched black shale Ni-Zn-Mo-PGE mineralization, Peel River, Yukon, Canada. Ore Geology Reviews. 2019. Vol. 107, pp. 600–614.
10. Snachev A. V., Latypov F. F., Snachev V. I., Rassomakhin M. A., Koschug D. G., Vyatkin S. V. Siraturskoe gold deposit in a crystal of the ophiolite association (South Urals). Bulletin of Moscow University. Ser. 4. Moscow: Geology. 2020. No. 5. pp. 64–70.
11. Bilibina T. V., Bogdanov Yu. V. On the prospects of gold bearing in the Mugodzhar region. Geology of ore deposits. 1959. No. 5. pp. 104–111.
12. Albov M. N. The secondary zoning of gold deposits of the Urals. Moscow: Gosgeoltekhizdat, 1960. 215 p.
13. Voin M. I. Features of the structure and mineralization of the Kumak ore field and the methodology for the allocation of enriched intervals in the mineralized zones of crushing. News of universities. Geology and exploration. 1966. Vol. 11, pp. 77–86.
14. Kolomoets A. V., Snachev A. V. Rassomakhin M. A. Gold–tourmaline mineralization in carbonaceous shales of the Kumak deposit (South Ural). Gornyi Zhurnal. 2020. Vol. 12. рр. 11–15. DOI: 10.17580/gzh.2020.12.02
15. Kolomoets A., Snachev A., Smoleva I. Carbonaceous matter in black-shale deposits of the Bredy Formation (Southern Urals). Kazan Golovkinsky Young Scientists "Stratigraphic Meeting 2020 and Young Scientists Summer School". 2020. Vol. 8. p. 37.
16. London D., Morgan G., Wolf M. Boron in granitic rocks and their contact aureoles. Reviews in Mineralogy. 1996. Vol. 33. pp. 299–330.
17. Baksheev I., Prokof’ev V. Y., Zaraisky G., Chitalin A., Yapaskurt V. et al. Tourmaline as a prospecting guide for the porphyry style deposits. European Journal of Mineralogy. 2012. Vol. 24, No. 6. рр. 957–979.
18. Jiang S.-J., Radvanec M., Nakamura E., Palmer M., Kobayashi K., Zhao H.-X., Zhao K.-D. Chemical and boron isotopic variations of tourmaline in the Hnilec granite-related hydrothermal system. Slovakia: Constraints on magmatic and metamorphic fluid evolution. Lithos. 2008. Vol. 106, No. 1. рр. 1–11.
19. Hazarika P., Mishra B. Tourmaline as fluid source indicator in the late Archean Hutti orogenic gold deposit. Mineral Resources in a Sustainable World: 13th SGA biennial meeting. Nancy. 2015. рр. 465–467.
20. Voudouris P., Baksheev I. A., Mavrogonatos C., Spry P. G., Djiba A. et al. Tourmaline from the Fakos porphyry-epithermal Cu-Mo-Au-Te prospect, Limnos island, Greece: mineralchemistry and genetic implications. Bulletin of the Geological Society of Greece. 2019. Vol. 7. рр. 329–330.
21. Rassomakhin M. A., Belogub E. V., Novoselov K. A., Khvorov P. V. Tourmaline from late quartz veins of the Murtykty gold deposit, South Ural, Bashkortostan. Mineralogy. 2020. Vol. 6, No. 1. рр. 69–83. DOI: 10.35597/2313-545X-2020-6-1-7
22. Serdyuchenko D. P. On some boron-rich sedimentary-metamorphic facies. Reports of the Academy of Sciences of the USSR. Moscow : Publishing house of the Academy of Science of the USSR. 1955. Vol. 102, No. 4.
23. Cabral A. R., Tupinamb M., Zeh A., Lehmann B., Wiedenbeck M., Brauns M., Kwitko-Ribeiro R. Platiniferous goldtourmaline aggregates in the gold-palladium belt of Minas Gerais, Brazil : implications for regional boron metasomatism. Mineralogy and Petrology. 2017. Vol. 111, No. 6. рр. 807–819.
24. Sokol E. V., Kokh S. N., Kozmenko O. A., Lavrushin V. Yu, Belogub E. V. et al. Boron in an onshore mud volcanic environment: Case-study from the Kerch Peninsula, the Caucasus continental collision zone. Chemical Geology. 2019. Vol. 525, рр. 58–81.

Full content Geology and gold content of carbonaceous shale in Baikal mineralization site, Southern Ural
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