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Asian Journal of Water, Environment and Pollution. Vol. 22, No. 1 (2025), pp. 33-41.
doi: 10.36922/ajwep.8113

ORIGINAL RESEARCH ARTICLE

Weathering of volcanic eruption products and rivers
contamination in Kamchatka

Sergey A. Voropaev* , Vyacheslav S. Sevastyanov , Nikitha V. Dushenko ,
Elena A. Tkachenko , and Irina N. Gromyak

Department of Carbon Geochemistry, Vernadsky Institute of Geochemistry and Analytical Chemistry (GEOKHI) of the
Russian Academy of Sciences (RAS), Kosygina str., Moscow, Russia
*Corresponding author: Sergey A. Voropaev (voropaev@geokhi.ru)

Received: December 21, 2024; 1st revised: February 7, 2025; 2nd revised: February 11, 2025;
3rd revised: February 21, 2025; Accepted: February 24, 2025; Published Online: March 5, 2025

Abstract: We investigated the biochemical weathering of unaltered lava and scoria samples from Tolbachik
volcanic field (Kamchatka). An experimental study on leaching of main (Si, Fe, Mg, Al, and Ca) and trace element
constituents (Li, Sr, Ba, V, Mn, Co, Ni, Cu, Ti, and other trace metals) was conducted. We used a 0.01 M (pH 2)
solutions of oxalic and acetic acids as analogs of natural bioorganic solvents. Meanwhile, a constant mass ratio
of solid and liquid phases was maintained. The results suggested that the mobilization of trace elements occurs
mainly as a result of the destruction of the crystalline structures of rock-forming minerals. In the case of oxalic acid
solution, Fe(III) and Mn(IV) oxyhydroxides are reduced to soluble Fe(II) and Mn(II) compounds. The formation
of organic complexes increases the stability of metals in solution and makes it possible to achieve significantly
higher concentrations of dissolved forms than in the absence of organic ligands. For example, water that has passed
through an old lava field covered with lichen may contain 2.5 times more Co than the maximum permissible
concentration for fish reproduction. This study demonstrated that the spikes in concentrations of heavy metals in
the Kamchatka River, observed during the 2015 – 2016 period, can be explained by the leaching of fresh products
from the Tolbachik Fissure Eruption (2012 – 2013).

Keywords: Leaching; Mobilization; Organic acids; Volcanic rocks; Heavy metals; Weathering

1. Introduction and platinum. The primary source of the overwhelming
majority of valuable metals is magmatic rocks. Their
The uniqueness of the Kamchatka Peninsula (Russia) weathering leads to the selective transition of chemical
lies in the fact that its territory contains the largest elements into a dissolved state. The development of
areas of natural spawning grounds of Pacific salmon the mining industry inevitably leads to the degradation
in Asia (Figure 1). As world experience has shown, of spawning rivers and a decrease in their fisheries
any economic development of the territory negatively potential. 1
affects the reproduction of salmon. The strategy of In recent years, when studying the formation
integrated development of the territory, which was of industrial ores, much attention has been paid to
adopted in Kamchatka, includes the development of trace elements responsible for modern technological
mineral deposits, in particular gold, polymetallic ores, development. An important role in the weathering

Volume 22 Issue 1 (2025) 33 doi: 10.36922/ajwep.8113