Ministry of Science and Education of the Republic of Azerbaijan, Institute of Geology (Baku, Azerbaijan)¹ ; Sergo Ordzhonikidze Russian State Geological Exploration University (Moscow, Russia)²

V. Yu. Kerimov, Chief Researcher¹, Head of Department, Doctor of Geological and Mineralogical Sciences, Professor², vagif.kerimov@mail.ru

Baku State University (Baku, Azerbaijan)

V. M. Babazade, Head of Department, Doctor of Geological and Mineralogical Sciences, Professor, Academician of the Azerbaijan National Academy of Sciences

Azerbaijan National Academy of Sciences (Baku, Azerbaijan)
I. S. Guliev, Vice-President, Doctor of Geological and Mineralogical Sciences, Academician of the Azerbaijan National Academy of Sciences

Sergo Ordzhonikidze Russian State Geological Exploration University (Moscow, Russia)
M. V. Zakharchenko, Candidate of Engineering Sciences, Associate Professor

This study assesses mud volcanoes as sources of renewable mineral raw materials and as indicators of hidden metallogeny in petroleum basins. The aim is to synthesize mineralogical, geochemical and isotopic data on mud volcanic ejecta (mud breccia, clay matrix, authigenic carbonates and sulfides) and on water–gas fluids in order to explain the mechanisms responsible for enrichment in rare earth elements (REE), uranium and precious metals. The study integrates optical and electron microscopy, X-ray diffraction, electron-microprobe analyses, and isotope mass spectrometry (C–O–S–Sr), combined with magnetic/electromagnetic fractionation to concentrate metal-bearing phases. The results indicate that mud volcanoes act as efficient conduits for deep fluid discharge, whereas metal accumulation is governed by redox barriers, pH–Eh shifts, rapid pressure drops and temperature contrasts during eruptions. REE and uranium are preferentially concentrated in the fine-grained matrix and in authigenic carbonates, while native and sulfide phases record strongly reducing conditions within migration channels. Prospectivity criteria for mud breccia as an unconventional resource are proposed, together with process routes for selective recovery of target components.

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