Special features of gold metallogeny in the areal of the North-Asian superplume influence

The outer contours of the projection of the North-Asian superplume repeat roughly the boundaries of the Amurskaya plate together with the adjacent marginal members of the Siberian and Chino-Korean cratons. In the areal of its influence, tens of gold deposits of different genesis and age (from Archean and Proterozoic to Paleozoic, Late Mesozoic, and Cenozoic) have been revealed and assessed. Many of the gold-bearing areas spatially join the gradient zones of the gravity field. Large gold-ore districts that in many aspects define the metallogenic character of the district are located near the joints of differently oriented gradient zones. In the best-studied districts, there has been established the presence of the Lower Precambrian protrusions, the stage-by-stage location of magmatic centers (by vertical) above the Mohorovicic discontinuity, evident spatial clastation of Au manifestations in the gold-bearing nodes, and frequent restriction of ore fields to the marginal peripheral parts of intrusive massifs. Some portion of gold mineralization of the district is centred in the Early Pre-Cambrian pre-accretion and Early Proterozoic collision metallogenic zones. So the gold deposits and ore occurrences revealed within them are a priori considered rather ancient. At the same time, in the region, the Charo-Olekminsky Archean greenstone megablock is known. On its area in the Uguisky gold-ore district there is the Tabornoye gold deposit associated with the dikes of the Late Jurassic syenite-porphyries. Actually, the main precious-metal mineralization of the region (industrial scale) was developed predominantly in the Late Paleozoic and Mesozoic time in the areal of the North-Asia superplume influence. In the indicated period, the magmagene, magmagene-hydrothermal, metamorphogene-hydrothermal, hydrothermal-sedimentary-metamorphogene, and hydrogenous ore-bearing systems were functioning here. They were responsible for the origination of:- Au-sulphide, Au-polysulphide, and Au-quartz deposits in the terrigenous-shale belts and terrigenous-plutonogenous zones; - Au-Cu-Mo-porphyric, Au-porphyric, Au-skarn, Au-sulphide-quartz, Au-rare metal, and Au-Ag deposits in the magmatic areal-plumes (magmagene-hydrothermal systems of different abyssal levels); - Au-sulphide-quartz (jasperoid) deposits in the cover of cratons and cratonized terrains;- deposits of gold-bearing weathering crusts and zones of oxidation (exogenous systems on the territory of Buryatia, Trans-Baikal, Priamurye, and Yakutia).When analysing the special features of the gold regional metallogeny it is necessary to account for the possibility of the ore-forming processes beginning in the Early Precambrian and for the critical influence of the North-Asian superplume derivates on their activation in the Late Palaeozoic-Mesozoic.

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