Petrography and Petrochemistry of Metamorphic and Igneous Rocks of the “Yeniseyskiy” Site
Abstract and keywords
Abstract:
In 2023, geological exploration of the “Yeniseyskiy” site (Krasnoyarsk Region), where a deep geological repository for radioactive waste (DGR) is planned, resumed. A detailed characterization of the rock composition, particularly tectonic faults as potential radionuclide migration pathways, is critical to ensuring the long-term safety of the site. The aim of the study was to classify the most significant structural elements of the site's rock mass in terms of mineral-deformational transformations, as well as to petrochemically characterize ancient metamorphic rocks and dike complex rocks to elucidate their genesis. The study is based on a comprehensive core analysis of 10 boreholes (up to 150 m deep), including petrographic analysis of thin sections, atomic emission spectrometry to determine the main oxides and rare earth elements, and statistical data processing. Two types of mineral-deformational transformations were identified. Type I (high- and medium-temperature) is associated with healed prototectonics zones, which are similar in properties to the unaltered massif. Type II (low-temperature) formed during hydrothermal-metasomatic transformations and characterizes potentially permeable paleotectonic faults. A schematic geological model has been constructed, including a classification of tectonic fault zones based on an analysis of these mineral-deformation transformations. Petrochemically, it has been established that gneisses (up to 80% of the section) are pararocks formed after graywackes and pelites in an active continental margin setting. Dolerites (17%) are classified as intraplate formations of the continental rift, and newly identified lamprophyres (3%) are calc-alkaline. The completed classification of tectonic faults allows them to be differentiated by their hydrogeological significance: zones with Type I transformations are considered conditionally impermeable, while crushed zones with Type II transformations require detailed hydrogeological monitoring as potential migration routes. The petrochemical data obtained on the genesis of the rocks form the basis for constructing geological and geomechanical models to justify the safety of the DGR.

Keywords:
Radioactive waste, radioactive waste disposal, underground research laboratory, petrography, petrochemistry
References

1. Anderson E. B., Belov S. V., Kamnev E. N., et al. Underground Isolation of Radioactive Waste. — M. : Gornaya Kniga, 2011. — 560 p. — EDN: https://elibrary.ru/RSVUYJ ; (in Russian).

2. Authors. Igneous Rocks. Classification, Nomenclature, Petrography (in 6 volumes). — Moscow : Nedra, 1983. — (In Russian).

3. Efremova S. V. and Stafeev K. G. Petrochemical Methods of Rock Exploration: A Reference Guide. — Moscow : Nedra, 1985. — 511 p. — (In Russian).

4. Evolution of the Southern Siberian Craton in the Precambrian / ed. by E. V. Sklyarov. — Novosibirsk : Publishing House of the SB RAS, 2006. — 367 p. — (In Russian).

5. Frumkin I. M. Early Archean geodynamic regimes in the Aldan Shield // Regional Geology and Metallogeny. — 2021. — No. 86. — P. 45–61. — https://doi.org/10.52349/08697892_2021_86_45-61. — (In Russian).

6. Ivanov A. I., Ivanov M. S., Loskutov E. E., et al. Petrography and petrochemistry of Mesozoic igneous rocks in the northeastern part of the Evota ore region (South Yakutia, Aldan Shield) // Vestnik of North-Eastern Federal University. Series "Earth Sciences". — 2022. — 4(28). — P. 25–42. — https://doi.org/10.25587/SVFU.2022.28.4.003. — (In Russian).

7. Kochkin B. T., Malkovsky V. I. and Yudintsev S. V. Scientific Foundations for Assessing the Safety of Geological Isolation of Long-Lived Radioactive Waste (Yenisei Project). — Moscow : IGEM RAS, 2017. — 384 p. — (In Russian).

8. Le Maitre R. W., Streckeisen A., Zanettin B., et al. Igneous Rocks: A Classification and Glossary of Terms. — Cambridge University Press, 2002. — 236 p. — https://doi.org/10.1017/cbo9780511535581.

9. Lobanov N. F., Beygul V. P., Lopatin P. V., et al. Selection and validation of area for underground research laboratory in Nizhnekansky Massif // Gornyi Zhurnal. — 2015. — No. 10. — P. 59–64. — https://doi.org/10.17580/gzh.2015.10.11. — (In Russian).

10. Lutz B. G. Geochemistry of Oceanic and Continental Magmatism. — Moscow : Nedra, 1980. — 247 p. — (In Russian).

11. Morozov O. A., Rastorguev A. V. and Neuvazhaev G. D. Assessing the state of the geological environment at the Yeniseyskiy site (Krasnoyarsk region) // Radioactive Waste. — 2019. — Vol. 9, no. 4. — P. 46–62. — https://doi.org/10.25283/2587-9707-2019-4-46-62. — (In Russian).

12. Ozerskiy A. and Ozerskiy D. Geological Environment of the Archean Crystalline Rock Massif for the Final Isolation of Radioactive Waste // 74th Geological Congress of Turkey with international participation, April 11-15. — Ankara, Turkey : TMMOB Chamber of Geological Engineers, 2022. — P. 30.

13. Ozerskiy A. Yu. and Polyakova E. G. History, results, and problems of the geological investigation of the Yenisseyskiy site for radio-active waste disposal // Radioactivity and radioactive elements in environment. Proceedings of VI international conference. September 20-24, 2021. — Tomsk : National Research Tomsk Polytechnic University, 2021. — P. 443–447. — (In Russian).

14. Petrographic Code of Russia. Igneous, Metamorphic, Metasomatic, and Impact Formations. 2nd Edition, Revised and Supplemented / ed. by O. A. Bogatikov, O. V. Petrov and L. N. Sharpenok. — St. Petersburg : VSEGEI, 2008. — 203 p. — (In Russian).

15. Petrov V. A., Poluektov V. V., Hammer J. R., et al. Analysis of mineralogical and deformation-induced transformations of Nizhnekansky Massif rocks to estimate their retention capacity in geological disposal and isolation of radioactive waste // Gornyi Zhurnal. — 2015. — No. 10. — P. 67–72. — https://doi.org/10.17580/gzh.2015.10.13. — (In Russian).

16. Pettijohn F. J., Potter P. E. and Siever R. Sand and Sandstone. — 2nd. — New York : Springer New York, 1987. — 553 p. — https://doi.org/10.1007/978-1-4612-1066-5.

17. Predovsky A. A. Reconstruction of the conditions of sedimentogenesis and volcanism in the Early Precambrian. — Leningrad : Nauka, 1980. — 152 p. — (In Russian).

18. Rock N. M. S. The nature and origin of lamprophyres: an overview // Geological Society, London, Special Publications. — 1987. — Vol. 30, no. 1. — P. 191–226. — https://doi.org/10.1144/gsl.sp.1987.030.01.09.

19. Roser B. P. and Korsch R. J. Determination of Tectonic Setting of Sandstone-Mudstone Suites Using SiO2 Content and K2O/Na2O Ratio // The Journal of Geology. — 1986. — Vol. 94, no. 5. — P. 635–650. — https://doi.org/10.1086/629071.

20. Sazonov A. M., Zablotsky K. A., Linnemann U., et al. Geochronology of sillimanite-cordierite gneiss Atamanovo series of the south Yenisei ridge (Russia) // Lithosphere (Russia). — 2017. — No. 2. — P. 49–59. — EDN: https://elibrary.ru/YMXUJV ; (in Russian).

21. Sharpenok L. N., Kostin A. E. and Kukharenko E. A. TAS diagram of the total alkalis and silica for chemical classification and diagnostics of plutonic rocks // Regional Geology and Metallogeny. — 2013. — No. 56. — P. 40–50. — EDN: https://elibrary.ru/STDKNV ; (in Russian).

22. State Geological Map of the Russian Federation. Scale 1:1,000,000 (third generation). Angara-Yenisei Series. Sheet O-46 - Krasnoyarsk. Explanatory Note / ed. by Yu. S. Glukhov. — St. Petersburg : VSEGEI Cartographic Factory, 2009. — 500 p. — (In Russian).

23. Zablotsky K. A. and Sopronchuk V. R. Reconstruction of the Primary Composition of Early Precambrian Metamorphic Rocks in the Southern Yenisei Ridge // Problems of Geology and Metallogeny of Krasnoyarsk Krai. — Novosibirsk : Nauka, 1989. — P. 100–109. — (In Russian).


Login or Create
* Forgot password?