The regularities of formation of noble- and rare-metal mineralization in Cenozoic coaliferous deposits in the southern Far East

Abstract

We performed system studies of age parageneses and lateral conjugation of peat and gold accumulation areas as well as the regularities of formation of noble-and rare-metal mineralization in Cenozoic coaliferous deposits in the south of the Russian Far East. The migration properties of noble metals (NMs) and their behavior in different media are considered. Based on literature data and results of experimental studies, we performed analysis and selection of the most optimal methods for the quantitative determination of NMs and trace and rare-earth elements. The experiments have confirmed the NB fugacity and have shown for the first time the scales of transportation of NMs as ultrafine particles during coal combustion. The obtained results significantly expand the notions of the migration properties of NMs and serve as the key to the solution of the problem of NM extraction in analytical and technological processes. Also, areas promising for noble-and rare-metal mineralization have been revealed in coal basins.

Enrichment of U-Re-V-Cr-Se and rare earth elements in the Late Permian coals of the Moxinpo Coalfield, Chongqing, China: Genetic implications from geochemical and mineralogical data

“…Rare metals in coal, e.g., V, Ge, Ga, rare earth elements and Y (REY, or REE if Y is not included), Sc, Se, Zr, Hf, Nb, Ta, Au, Re, and U, as well as the base metal Al, have attracted much attention in recent years (e.g., Seredin and Dai, 2012;Li et al, 2014b,c;Jiang et al, 2015;Hower et al, 2016a,b;Sorokin et al, 2013) as the concentrations of these metals in the ashes of some coals, and in some rocks adjacent to the coal seams, are equal to or even higher than those found in conventional types of rare metal ores (Seredin and Finkelman, 2008;Seredin and Dai, 2012;Seredin et al, 2013). Coal, and especially coal combustion byproducts, can offer an opportunity to acquire valuable resources without the costs and environmental impacts of traditional mining and with the added benefit of reducing the amount of byproducts to dispose of.…”

Gold-Bearing Brown Coal Deposits of the Zeya–Bureya Sedimentary Basin (East Russia): Fundamental Model of Formation

“…Our previous studies dealt with the distribution of gold in coal-bearing deposits of the Zeya-Bureya basin and mountain massifs [15][16][17][18]. In the Late Cretaceous and Paleogene, gold deposits were subjected to intense weathering processes and served as sources of gold and other ore components for coal-bearing deposits.…”

Distribution of rare earth and selected trace elements in combustion products of Yerkovetskoe brown coal deposit (Amur Region, Russia)

“…The main source of rare earth and trace elements in coal deposits of the Amur region are products of the physical disintegration and chemical decomposition of rocks and numerous ore veins, located in the rocky frame of the Zeya-Bureya coal-bearing sedimentary Basin, and their distribution within the emerging strata of coal, influenced the type of vegetation and plant debris, transported by streams and catastrophic floods to depositional sites on the territory of coal-forming peat mires, physicochemical parameters of vegetation maturing during their conversion (diagenetic alteration) into brown coal, as well as the sorption properties of inclusions and interlayers of organic pitch, bitumen, and humic acids in peat and coal beds. Accessory minerals in the brown coal deposits of the Basin are concentrators of economically valuable metals and elements, the amount of which is correlated also with content of ash in coal, which ranges from 9 to 20 wt.% (Sorokin et al., 2013).…”

“…Increased metal concentration is peculiar to brown coal from many deposits of the world (Seredin et al., 2013; Shpirt et al., 1999; Singh et al., 2016; Sorokin et al., 2013; Sun et al., 2010), therefore, the CCP are considered by many scientists as potential additional sources of noble metals and rare earth and trace elements (Kolkera et al., 2017; Sorokin and Konyushok, 2018).…”