Material characteristic of Vetvisty creek placer gold and prospects for atypical-source deposits in the middle course of the Selennyakh river (Momsky and Abyisky district, Yakutia)

Background. The lower-middle course of the Selennyakh River in the Momsky and Abyisky districts of the Republic of Sakha, Yakutia, is characterized by a wide distribution of alluvial gold placers. The absence of obvious potential primary sources of these placers raises the question of their identification. Aim. To identify sources of gold placers found in interfluve area of the Selennyakh and Indigirka rivers, as well as to assess the gold-bearing potential of this area.Materials and methods. The data on the studied area obtained in previous works was analyzed. Microprobe analysis (CSRF IGEM RAS) was used to study the composition of alluvial gold grains sampled during field works in the Vetvisty Creek, the right tributary of the Selennyakh River, conducted in 2020–2021. The mineral composition of heavy concentrate was also studied.Results. The source of the gold placer under study was established to be an intermediate reservoir, i.e., Neogene coarse sand and gravel. Possible paths of gold transit within the placer were revealed. Theoretically, this allows enriched layers in the sediments feeding the placer to be localized.Conclusion. In order to replenish the gold mineral base of the country, including in such hard-toreach regions as the Arctic zone of the Russian Federation, regional research projects should be resumed. In addition, new models should be developed for forecasting and prospecting of atypical placer deposits, with gold sources from Tertiary sediments filling large Cenozoic depressions in the western rim of the Yano-Indigirskaya lowland).

placers, gold, Arctic zone of the Russian Federation, intermediate reservoir, Neogene, Tertiary sediments