Vol 55, No 4 (2017)

Pyroxenite veins in mantle peridotites of the Unnavayam sheet of the Kuyul ophiolite terrane (Koryak—Kamchatka folded area) are composed of clinopyroxenite and websterite crystallized from a boninite-like melt. The host clinopyroxene-bearing spinel harzburgites are moderately depleted residues, whose mineral compositions and conditions of formation correspond to those of peridotites from mid-oceanic and back-arc spreading centers. Mantle peridotites of the Unnavayam sheet may have formed a part of the mantle wedge above a subduction zone and have been intruded by boninitic melts at a certain stage of their evolution.

Fluorite solubility in HCl and HF solutions with varied concentrations of boric acid was studied at 81, 155, and 208°C and saturated vapor pressure. Our experimental results demonstrate that fluorite solubility increases with increasing B(OH)₃ concentration, and this was interpreted as the formation of the BF3OH–complex (Ryss, 1956). The experimental data were used to determine, using the OptimA software, the free energies of formation of HF°(aq) and, which were then used to calculate the constants of the reactions HF = H⁺ + F^– (1) and B(OH)₃(aq) + 2H⁺ + 3 F^– (2). The pK₁ values are 3.71 ± 0.013, 4.28 ± 0.015, and 4.89 ± 0.017 and pK₂ 13.60 ± 0.02, 13.99 ± 0.02, and 14.95 ± 0.03 at saturated vapor pressure and 81, 155, and 208°C, respectively.

Concentrations and composition of suspended particulate matter and organic compounds (OC), including Сorg, lipids, hydrocarbons (HC), and pigments, were determined in the near-water aerosol layer and in surface waters on the meridional section across the Atlantic Ocean from the port of Ushuaia to the port of Gdansk (Cruise 47^th of the R/V Akademic Ioffe, March 26–May, 7, 2015). It was established that the distribution of OC (except for pigments) in aerosols, in general, repeats the distribution of particle number and weight concentrations of aerosols, with maximums in the influence zone of fluxes from Patagonia and African deserts. The concentrations of aerosols changed within wide ranges: from 1237 to 111739 particles/L for 0.3–1 μm fraction; and from 0.02 to 19.890 μg/m³ for aerosols collected by network method (flux of 0.02–34.4 mg/m² day). The contrasting mineral composition of aeolian material reflects the diversity of its provenances. In surface waters, the studied compounds were accumulated in the frontal river–sea area (runoff of the Rio-Colorado River) and with approaching the coast, especially in the English Channel. A simultaneous change of concentrations of suspended particulate matter and OC is observed only in open oceanic waters.

The paper presents data on the possibility of ETAAS analysis, and a technique of this analysis, of salt rocks, their insoluble residues, and organic fractions from these rocks for Au, Pt, and Pd (concentrations from 10^–7 to 10^–2 ppm). Various techniques for the decomposition of the samples are discussed, and the paper presents information on the extent of Au, Pt, and Pd adsorption from chloride complexes when the POLYORGS-IV complex-forming adsorption agent is applied. The determined atomization parameters of the elements in a graphite furnace are reported. Precious metals are proved to be concentrated in the insoluble residues of the salt rocks and in the slimes (salt wastes) when the salt rocks are processed. The forms in which precious metals are contained in the salt-bearing rocks are determined.

The paper presents author’s data on the composition of water-soluble organic matter in thermal, cold groundwaters, and surface waters in the Annenskii geothermal field. The waters contain 75 organic compounds of 13 homologous series, with 72 of these compounds identified in the thermal waters. The compounds are mostly of biogenic origin. Organic matter in the thermal waters differs from that in the cold groundwaters in containing nitrogen-bearing compounds, isoalkanes and alkenes. The compositional specifics of the saturated hydrocarbons suggests their partly abiogenic origin.