Tectono-magmatic controls on placer and lode gold mineralization in the Central Aldan district (Southern Yakutia)

The article presents generalized results of a comprehensive study of tectono-magmatic factors controlling placer and lode gold mineralization in the Central Aldan District (CAD) – a classic province of tectono-magmatic activation. Analysis of archival materials, published data, and research by leading regional specialists established that the modern geodynamic model of the region results from the superposition of several tectonic stages: Archean (formation of the crystalline basement), Platform (accumulation of Vendian–Lower Cambrian carbonate cover), Mesozoic activation, and Neotectonic. A detailed analysis incorporating the works of Vetluzhskikh V.G., Kochetkov A.Y., Boytsov V.E., and Maximov E.P. substantiated the leading role of Mesozoic tectono-magmatic activation in the formation of a unique ore-magmatic system. Precisely during this period (220-145 Ma), the reactivation of ancient deep-seated faults, the emplacement of multiphase alkaline-granitoid intrusions, and the formation of the vast majority of both primary (Lebedinskoye, Koltykonskoye fields) and associated placer mineralization occurred.

Spatio-temporal relationships between fault zones, Mesozoic magmatism, and the localization of ore bodies have been identified. Ore control criteria have been established, including confinement to fault intersection nodes and association with specific intrusive complexes. The Neotectonic stage, characterized by the formation of graben-valleys, predetermined the final localization and preservation of placer deposits. The developed model is fundamental for understanding the metallogeny of the Aldan Shield and serves as a basis for developing enhanced predictive-exploration criteria for gold. The obtained results enable the identification of the most promising areas for exploration within the Central Aldan District. The research materials are of significant practical interest for geological survey organizations and subsoil users in the region.

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