This study investigates the petrological, geochemical, and geodynamic characteristics of intrusive and sub volcanic rocks within the Bektakari–Bnelikhevi ore knot, situated in the southern segment of the Lesser Caucasus. The research integrates detailed mineragraphic observations with whole-rock geochemical data obtained from 17 samples collected from eight drill cores. Major and trace element compositions were determined using X-ray fluorescence (XRF) spectrometry, providing a robust dataset for evaluating magma evolution and hydrothermal alteration processes. Petrographic examination reveals significant variability in mineral assemblages, textures, and alteration patterns, reflecting complex magmatic differentiation and subsequent hydrothermal overprinting. The intrusive rocks display systematic compositional trends consistent with a calc-alkaline magmatic series generated in a subduction-related tectonic environment and influenced by mantle-derived melts interacting with crustal components. Geochemical discrimination diagrams show pronounced enrichment in large-ion lithophile elements (LILE) together with depletion in high-field-strength elements (HFSE), supporting formation in a convergent margin setting associated with arc magmatism. Mineragraphic observations of sulfide assemblages, including pyrite, chalcopyrite, sphalerite, and galena, indicate multiple stages of hydrothermal mineralisation linked to evolving magmatic fluids and structural pathways for fluid migration. These features collectively suggest the presence of a long-lived magmatic–hydrothermal system capable of generating   metal-enriched fluids and favourable conditions for ore deposition. The results highlight the metallogenic significance of the Bektakari–Bnelikhevi ore knot and contribute to a broader understanding of arc-related mineralisation processes within the Lesser Caucasus sector of the Tethyan metallogenic belt.

Keywords: hydrothermal alteration, geochemistry, mineralisation, magmatism

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