STRUCTURAL EVOLUTION OF THE DAVENDA-KLYUCHEVSKOE ORE CLUSTER AND CONTROL OF Mo-Au MINERALIZATION IN THE POST-COLLISIONAL SETTING (EASTERN TRANSBAIKALIA)

The paper presents the results of the detailed geological structural studies of the Davenda-Klyuchevskoe ore cluster (Eastern Transbaikalia), including the Davenda Mo deposit, Klyuchevskoe gold ore deposit, and Borovoe ore occurrence. It has been found that the structure of the ore cluster is determined by a combination of heterochronous fault systems controlling magmatism and ore deposition. There are distinguished two main types of ore stockworks: linear (Davenda), confined to the North-Eastern fault system-1, and areal (Klyuchevskoe), formed at the intersection of the Shirotny, North-Western and North-Eastern-2 faults. It has been shown that the North-Eastern fault-1, initiated as early as during the consolidation of the Mongol-Okhotsk suture, controlled the intrusion of granitoids of the Amanan complex (159 Ma) and the subsequent formation of quartz-molybdenite veins.

At the Klyuchevskoe deposit, there are distinguished three ore-controlling fault systems: Shirotny (right-lateral shear), North-Western (right-lateral shear) and the North-Eastern fault-2 (detachment). They formed during a short period about 150 Ma ago synchronously with the early stage of formation of the Amudzhikan-Sretensk complex and were accompanied by explosive processes which gave rise to the occurrence of complex brecciated ore bodies. Analysis has been made on the kinematic characteristics of faults and their relationships with dikes of different composition. The data obtained make it possible to update the structural-kinematic model of the ore cluster and to determine the relative age of mineralization.

1. Benevolsky B.I., 2002. Gold of Russia: The Problems of Use and Reproduction of Mineral Resources. Geoinformtsentr, Moscow, 464 p. (in Russian).

2. Berzina A.P., Berzina A.N., Gimon V.O., Bayanova T.B., Kiseleva V.Y., Krymskii R.S., Lepekhina E.N., Palesskii S.V., 2015. The Zhireken Porphyry Mo Ore-Magmatic System (Eastern Transbaikalia): U-Pb Age, Sources, and Geodynamic Setting. Russian Geology and Geophysics 56 (3), 446–465. https://doi.org/10.1016/j.rgg.2015.02.006.

3. Borovikov A.A., Kalinin Y.A., Sukhorukov V.P., Abramov B.N., 2020. Ore-Forming Fluids of the Aleksandrovskoe and Davenda Deposits (Eastern Transbaikalia). Geology of Ore Deposits 62 (4), 288–313. https://doi.org/10.1134/S1075701520040030.

4. Chernyshev I.V., Prokof’ev V.Y., Bortnikov N.S., Chugaev A.V., Goltsman Y.V., Lebedev V.A., Larionova Y.O., Zorina L.D., 2014. Age of Granodiorite Porphyry and Beresite from the Darasun Gold Field, Eastern Transbaikal Region, Russia. Geology of Ore Deposits 56 (1), 1–14. https://doi.org/10.1134/S1075701514010036.

5. Gordienko I.V., Badmatsyrenova R.A., Lantseva V.S., Elbaev A.L., 2019. Selenga Ore District in Western Transbaikalia: Structural-Minerogenic Zoning, Genetic Types of Ore Deposits, and Geodynamic Settings of Ore Localization. Geology of Ore Deposits 61 (5), 391–421. https://doi.org/10.1134/S1075701519050027.

6. Karelin S.P., Tombasov I.A., 2010. Near-Surface Gold-Silver Deposits of the Trans-Baikal Territory. In: Geology and minerageny of Transbaikalia. Collection of Reports and Articles for the Research and Production Conference Dedicated to the 60th Anniversary of FSUGE Chitageols’emka (October 22–23, 2010). Transbaikalia State University, Chita, p. 175–183 (in Russian).

7. Khaziakhmetov E.I., Yakubchuk A.S., Shatov V.V., Rodionov N.V., Sergeev S.A., Chugaev A.V., 2026 (in press). U-Pb Geochronology of Granitoids of the Amanakan and Amudzhikan Complexes and Their Relationship with Porphyry Mineralization in the Sergeevskoe Deposit (Eastern Transbaikalia). Russian Geology and Geophysics (in Russian).

8. Khubanov V.B., Dugdanova E.E., Tsygankov A.A., Buyantuev M.D., 2017. The Age Ratios of Alkaline and Molybdenite Granitoids of the Selenga Molybdenum Ore-Bearing Area (Western Transbaikalia). In: Granites and the Earth’s Evolution. Proceedings of the III International Geological Conference (August 28–31, 2017). IGG UB RAS, Ekaterinburg, p. 330 (in Russian).

9. Kovach V.P., Kotov A.B., Larin A.M., Sal’nikova E.B., Velikoslavinskii S.D., Yakovleva S.Z., Plotkina Y.V., 2018. Age and Boundaries of the Olekma Magmatic Belt of the Selenga–Stanovoi Superterrane (Central Asian Mobile Belt). Doklady Earth Sciences 483 (1), 1375–1379. https://doi.org/10.1134/S1028334X1811003X.

10. Kreimer S.I., 2007. Feasibility Study of Permanent Exploration Standards for Open-Pit Mining of the Klyuchevskoye Gold Deposit: Research Report. Book 1. Iss. 1. Saint Petersburg, 157 p. (in Russian).

11. Larin A.M. et al., 2024 (in рress). Adaktite-Like Granitoids of the Amudzhikan-Sretensk Complex in Eastern Transbaikalia: Geochemistry, Sources, Geodynamic Environment. Russian Geology and Geophysics (in Russian).

12. Larin A.M. et al., 2025 (in press). Post-Collisional Orogenic Collapse and Formation of Granitoids of the Amudzhikan-Sretensk Complex (Eastern Transbaikalia). Geotectonics (in Russian).

13. Larin A.M., Kotov A.B., Kovach V.P., Sal’nikova E.B., Yarmolyuk V.V., Velikoslavinskii S.D., Yakovleva S.Z., Plotkina Y.V., 2015. Granitoids of the Olekma Complex in the Selenga–Stanovoi Superterrane of the Central Asian Mobile Belt: Age and Tectonic Position. Doklady Earth Sciences 464 (1), 903–906. https://doi.org/10.1134/S1028334X15090093.

14. Leifman Yu.M., 1965. On the Role of Latitudinal Faults in the Structure of the Klyuchevskoe-Davenda Ore Cluster. Proceedings of Higher Educational Establishments. Geology and Exploration 3, 45–52 (in Russian).

15. Spiridonov A.M., Zorina L.D., Kitaev N.A., 2006. Gold-Bearing Ore-Magmatic Systems of Transbaikalia. GEO, Novosibirsk, 291 p. (in Russian).

16. Svetlitskaya T.V., Nevolko P.A., Bortnikov N.S., Chugaev A.V., 2026 (in press). The Timing of Gold Quartz-Tourmaline Mineralization and the Magmatic Fertility at the Klyuchevskoe Deposit, Eastern Transbaikalia, Russia: Records from U-Pb Zircon Geochronology and Whole-Rock and Zircon Mineral Geochemistry. Geoscience Frontiers.

17. Volfson F.I., Yakovlev P.D., 1975. Structure of Ore Fields and Deposits. Textbook. Nedra, Moscow, 271 p. (in Russian).

18. Xiao L., Clemens J.D., 2007. Origin of Potassic (C-Type) Adakite Magmas: Experimental and Field Constraints. Lithos 95 (3‒4), 399‒414. https://doi.org/10.1016/j.lithos.2006.09.002.

19. Yakubchuk A., Lobanov K., Shmatov S., 2025. The Davenda-Klyuchevskoe Au-Mo-(Cu) Cluster in the Mogocha Gold District (Russia): An Intrusion-Related or Porphyry System Overprinted by Epithermal Gold? Mineralium Deposita 60 (1), 47‒62. https://doi.org/10.1007/s00126-024-01302-2.