Accumulation and fractionation of rare earth elements in surface waters of the Russian Far East under the conditions of natural and anthropogenic anomalies

The distribution and fractionation of rare earth elements were studied in surface waters from areas with different anthropogenic impacts in the southern part of the Russian Far East and in natural anomalous waters from areas with intense volcanic-hydrothermal activity. The levels of REE contents and their fractionation in the sequence from the light to heavy REE were estimated in different waters, and their connections with major ions and other trace elements, primarily Al, Fe, and Mn, were determined. The relations of the main forms of REE migration (dissolved and suspended) in surface waters were evaluated, and fundamental differences were detected in the accumulation of REE in the natural acid waters of the Kuril Islands and under continental conditions related to their deep input and redistribution in streams.     

Geochemistry of the thermal waters of Sikhote Alin

This paper reports new geochemical data on the low temperature nitric thermal waters of Sikhote Alin. The studied alkaline waters belong to the HCO₃-Na type with significant trace element variations. The waters demonstrate an increase in temperature and TDS from the south northward of Sikhote Alin. The oxygen and hydrogen isotopic data suggest their infiltration origin. The chemical composition of these waters was formed by water-rock interaction.     

Chemical and isotopic (<Superscript>18</Superscript>O/<Superscript>16</Superscript>O and D/<Superscript>1</Superscript>H) composition of groundwaters of central and southern Primorye

Groundwaters of Primorye, including its coastal areas, were studied during the past ten years. The macro-and microelement composition of more than 130 samples showed that shallow groundwaters of southern Primorye with pH ranging between 5.4 and 8.4 contain oxygen (up to 10 mg/l) and typically have a mixed ionic composition. The microelement variations reflect both the natural features of the host rocks and possible anthropogenic pollution in the most populated areas. No seawater intrusions were recognized in the study areas, which is confirmed by the chemical composition of the waters, the oxygen and hydrogen isotopic composition of the groundwaters, the atmospheric precipitation, and the coastal seawaters of Primorye. In spite of the variations of individual components, the quality of the groundwaters used for potable purposes is rather satisfactory as compared to the Russian and the World Health Organization standards. At the same time, taking into account the increase of various microelements and biogenic components in the waters, the monitoring and control of the water composition is strongly recommended to preserve their potable quality.     

Trace elements in surface water in Amur River basin

A wide range of trace elements contained in solution and suspension in surface waters in Amur River basin, which are subject to different anthropogenic load, has been considered. They have been found to vary widely because of their natural conditions, the impact of anthropogenic factors near cities (Khabarovsk, Komsomol’sk-on-Amur), and transboundary transport from the territory of China. Dissolved Mo, Br, and I are proposed as tracers of such transport.     

Chemistry of rainwaters in the south Pacific area of Russia

On the south-eastern edge of Russia, the chemical composition of rainwater is controlled by sea salts, terrestrial material, as well as volcanic (Kuril islands volcanic area) and anthropogenic emissions, mostly in the southern part of the area. The predominant major ions of the Primorye, Sakhalin and the Kuril Islands rainwaters were respectively HCO₃⁻–SO₄²⁻, Ca–Na, and of Cl–Na. Concentration of trace elements changes within 1–2 orders of magnitude but some difference in the distribution of the elements between continental and island rainwater is found. The concentration of the chemical elements in the particulate fraction varies from < 10% to 90% of the total concentration (dissolved + particulate) with the following distribution: Tl, Na, Ca, Sr, Zn, Cd (< 10%)–Be, Th, Bi, Rb, U, K, Sc (10–20%)–Cu, Mn, Mg, Mo, Se, Ba, Ni, As, Ag, Cs, Co, Y, Ga, V (20–50%)–Sb, Pb, Ge, Cr, Fe, Al (50–90%).The concentration of elements of the particulate fraction of the rainwater usually is significantly different from concentrations in the crust, including both higher and lower concentrations. The terrestrial contribution to dissolved elements was evaluated and follows the decreasing order: Fe > K, Mg, Ca > Ba, Sr > Na (65–1%). Close order was found for total (dissolved and solid) concentrations. Sea salt contribution to dissolved element concentration in the rainwater decrease in the following order: Cl, Mg > K, SO₄ > Ca > HCO₃⁻, Ba, Fe (78–0.1%). Calculation of anthropogenic and volcanic inputs for two ions (Cl⁻ and SO₄²⁻) shows that anthropogenic inputs for the Vladivostok and Yuzno-Sakhalinsk cities can be evaluated as 15–20% of Cl⁻ and up to 80–90% of SO₄²⁻. Volcanic components in the Kuril Islands, where anthropogenic inputs are absent, can reach up to 76% of SO₄²⁻ and 36% of Cl⁻.     

Geochemistry of recent hydrothermal systems of Mendeleev Volcano, Kuril Islands, Russia

Among the thermal waters of Mendeleev Volcano three main types can be distinguished: sodium-chloride, acid-sulfate and chloride–sulfate–bicarbonate waters. Contents and behaviors of siderophile, chalcophile, lithophile, and rare-earth elements are discussed. These data, together with the result of isotopic studies (oxygen and hydrogen), are used to discuss the origin of these waters. From the three types of thermal waters, only acid-sulfate waters have a significant input on the chemical composition of the surrounding surface waters.     

Chemical composition of precipitation in the southern part of the Russian Far East

Distribution of macro-and microelements, found in precipitation in dissolved and suspended forms (solid material) is considered. Contribution of the main sources of substance input in the precipitation on the investigated area is assessed.