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Voropaev, et al.

see Supplementary File Figures 1-4). They were precursor (100% purity), in accordance with Russian
predominantly basaltic, with two distinguished types: state standard #19814 – 74. The chemical composition
high-magnesian and high-alumina basalts. During the of volcanic scoria is given in Tables 1 and 2. The
early eruption of 1975 (Northern Breakthrough, scoria experiments were carried out for water and acid with
cones I, II, and III), pyroclastic ejections predominated a mass ratio of rock and solution equal to 1:10 (50 g
in composition corresponding to magnesian basalts. sample and 500 mL solution). In some cases, suspensions
Their main minerals are olivine (Fo85 – 99), diopside, were stirred daily in an ultrasonic bath for a consecutive
diopside-augite (Ca42 – 45-Mg 44 – 50-Fe 7 – 11), 5 days, with 15 min each time, and then the solutions
and plagioclase (An74 – An55). The main stage of the obtained after leaching (extract) were decanted.
2012 – 2013 eruption (e.g., scoria cone Naboko) was The microelements content in the extract was
characterized mainly by basaltic lavas. Compositionally, determined by our team with inductively coupled plasma
plagioclase of Naboko vent lavas ranges from An70 – 72 atomic emission spectroscopy (ICP-AES) method
to An80 – 80, olivine ranges from Fo64 to Fo75 (mainly iCAP6500 (Thermo Scientific). ICP-AES is heavily
found as microphenocrysts), and clinopyroxene ranges used at GEOKHI RAS. It allows for determination of
from augite to salite. Fumarole activity of GTFE and the multi-element composition of the studied objects.
12
TFE continues until the present day. The fumaroles of The principle of the method is that the test sample is
13
the scoria cones are characterized by a wide variety of transferred to a solution, which is sprayed into the
minerals and mineral-forming elements. A significant device in the form of an aerosol. The study was carried
number of new minerals were discovered there. 14
We know of only a few works that studied the effect Table 1. Main elements composition of various
of organic acids on the transition of trace metals from Tolbachik lava and scoria samples a
rocks to a dissolved state. From a methodological Main oxide, Scoria, s1 Scoria, s2 Lava, l1 Lava, l2
point of view, these studies were imperfect – first, wt. %
they lacked either the initial content of trace metals SiO 50.57 55.69 51.06 55.98
2
in rocks ; second, the magnitude of mobilization was Na O 2.95 3.12 3.37 3.41
15
determined depending on the specific composition of 2
the magmatic rock. The purpose of our work was to MgO 6.43 5.11 4.15 3.14
16
determine the quantitative characteristics of the trace Al O 3 13.54 14.59 12.68 13.60
2
metals’ mobilization from magmatic rocks under the K O 1.26 1.87 2.37 3.45
2
action of dilute solutions of organic acids, which are CaO 10.42 8.71 8.84 6.29
typical components of surface and groundwater in FeO 12.59 8.41 13.84 10.15
tot
volcanic regions. Many of the above metals are toxic Note: Our team carried out analysis using X-ray fluorescence
a
and their high presence in natural waters is dangerous (XRF) method in GEOKHI RAS.
for agriculture and people. Abbreviation: GEOKHI RAS: Geochemistry and analytical
chemistry of the Russian academy of sciences.
4. Extraction method
Table 2. Trace metals abundance of the Tolbachik
To study the weathering features of volcanic rocks scoria samples (μg/g)
(laboratory simulation of biochemical weathering Element Concentration Element Concentration
processes), we used unaltered fresh lava and scoria Li 20 Nb 7
(fractions from 0.1 mm to 2 cm) from the Tolbachik
volcano, Kamchatka. Samples were collected during Cs 2.2 Mo 7
the expedition of our team from the Vernadsky Institute Ba 582 Ag 0,1
of Geochemistry and Analytical Chemistry of the V 276 Sn 1,6
Russian Academy of Sciences (GEOKHI RAS) in Cr 4 Sb 0,46
2020 to the Kamchatka Peninsula. The scoria samples Co 22 Te <0.05
were treated with distilled water and 0.01 M of oxalic Ni 9 Rb 64
(HOOC-COOH) and acetic (CH -COOH) acids. The Cu 242 Sr 329
3
acid solutions were prepared by thorough mechanical
mixing with distilled water – first, from a solid powder of Zn 103 Y 40
oxalic acid (99.75% purity); second, with the acetic acid Ga 19 Zr 237

Volume 22 Issue 1 (2025) 36 doi: 10.36922/ajwep.8113