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Sensitive high-resolution ion microprobe (SHRIMP) U-Pb ages for detrital zircons from the Caspian region reveal the age ranges of basement terrains that supplied the sediment.

The South Caspian Basin has accumulated a sedimentary succession ∼20 km thick. Roughly half of this was deposited in the last 5.5 Ma, mainly in the largely lower Pliocene, fluvio‐lacustrine Productive Series, which is also the principal hydrocarbon reservoir succession in the basin. Heavy mineral data identify different sediment sources for both Productive Series sandstones and modern river sands. Lesser Caucasus sediment was supplied by the Palaeo‐Kura into the western part of the South Caspian Basin. Productive Series strata in the north of the basin were supplied by the Palaeo‐Volga, and represent a mixture of sediment from the Greater Caucasus and Russian Platform/Urals. Greater Caucasus sand input to the Palaeo‐Volga increased at the start of deposition of the Pereriva Suite, which is an important reservoir subunit of the Productive Series. We interpret this provenance shift as indicating enhanced uplift and exhumation of the Greater Caucasus within the Pliocene, during regional re‐organization of the Arabia–Eurasia collision, although late Cenozoic climate changes may have played a role.

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Wustite (for the first time defined by authors in the territory of Azerbaijan) and native iron are found in the slag-like fragments of rocks (scorias) contained in the river alluvium above flood-plain terraces of Ganjachay and its small tributaries within the eastern periphery of Dashkesan trough (Lok-Garabagh zone of Lesser Caucasus). They represent following two types of burnt, dense and lumpy bubble-rocks: 1basaltoids with typical spinifex structure and native iron and magnetite content; 2granitoids with impregnations of the different-size fragments of wustites, as well as magnetites, maghemites, etc. First type of the metal-bearing rocks corresponds to low-titanium and komatiite-like ferro-magnesian formations (pyroxene komatiites -?), while the second type is represented by diorites-quartz diorites. Materials of the conducted research bring us to a conclusion that wustite and other metal-bearing formations are brought to a daylight through the hybrid magma with quartz-diorite composition which have formed through mixing of the palingenic granitoid magma with the serpentized rocks of buried ultrabasic plate. Studied samples represent fragments of a deep magmatic focusultrabasic rocks that had been recrystallized into komatiites (?) as well as fragments of the marginal zones of magma generation focus, e.g. melted granitoids with wustite, magnetite, maghemite, etc., ejected by an explosive activity of paleo volcanoes.

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Gold-bearing ore deposits of the Lesser Caucasus are confined to Meso-Cenozoic subsequently-differentiated volcano-plutonic formations with gabbro-diorite-granodiorite-granite facies which are of crustal-mantle subduction formations of island-arc continental margins. Genetic types of gold-bearing ore deposits are confined to three structural-formational zones: Lok-Garabagh, Geycha-Akera and Ordubad forming during Newkimmerian (J3-K1), Austrian (К1-K2) and Pyrenean (Р2-Р3) phases of tectonic-magmatic activizations corresponding to the geodynamic regimes of multi-event manifestation of mantle diapirism stipulating occurrence of the back-arc extension (spreading). Their formation starts with the basite alongside with the acid facies of island-arc complexes following the formation of single copper pyritepolymetalline ore-magmatic system with gold-bearing ore mineralization. Polingenic melting of initial granitoid magmatic melt causes the last stage formation of differentiation for rhyolite-dacite differences, with fluids to be interlinked by hydrothermal gold mineralization. Its further interaction with gold extracted from mantle-serpentinized rocks of ultrabasic complex of oceanic crust. The processes of multiple melting and gold redirection from rocks into the fluid causes concentration and formation of goldbearing ore accumulations.