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For an improved understanding of metal behavior in soils, studies on geochemical changes occurring in a specific grain-size fraction during pedogenesis and lateral translocation of soil material are needed. In the present research we analyzed the concentrations and vertical distributions of Fe, Mn, Cu, Ni, Co, Cr, Zn, Pb, Ti, Zr in coarse and medium sand fraction of the major soil types of the middle Protva basin, situated in the mixed forest zone of European Russia, and described patterns of downslope (lateral) distribution of metals in the humus horizons along two catenas and two types of small erosional systems. The observed concentrations for all metals in the fraction 1–0.25 mm, except of Mn, conform to the natural geogenic concentrations reported previously in literature. The majority of the metals exhibit high natural variability in concentrations in the sand fraction. Higher metal concentrations are found either in the topsoil horizons or in parent material and underlying stratum. Studying lateral aspects of metal distribution in the sand fraction of humus horizons revealed a decrease in Mn, Zn, Pb, Co, Ti and an increase in Fe, Cr and Ni levels of the lower sections of the slopes. The similarity of metal concentrations in the sand fraction in these positions across two catenas implies the importance of the geochemical convergence processes operating in downslope direction. The small erosional landforms, a gully and a dry U-shaped valley, show similar patterns in lateral distribution of Fe, Cu, Ni, Cr, Zr, Zn, but they differ in terms of Pb, Co and Mn behavior across their elementary units: adjacent areas, slopes and bottom. The results imply that the features of vertical (within the soil profiles) and lateral (along catenas and small erosional systems) distributions of metals are significantly controlled by the provenance of the sand fraction, although at the same time some variations in metal contents seem are attributed to chemical transformations of the sand fraction due to pedogenic processes and during downslope translocation of soil material. [ABSTRACT FROM AUTHOR]

Three styles of platinum-group element mineralization occur within the Ural-Alaskan type complexes of the Uralian Platinum belt: chromite-platinum, noble metal, and noble metal-copper ones. They are associated with dunite and chromitite (chromite-platinum), pyroxenite (noble metal) and gabbro (noble metal-copper). Three common platinum group element distribution patterns are observed for dunite and chromitite: (1) M-shaped (defined by positive Ir and Pt anomalies); (2) with positive Ir-Rh(Pt) anomalies; and (3) W-shaped with positive Os and Pt, or Os and Rh anomalies. In contrast, pyroxenite and gabbro are enriched in Pd and Au. The PGM assemblages correlate to the PGE + Au distribution patterns as exemplified by the predominance of Ir-rich Pt-Fe alloys within dunite and chromitite. The noble metal assemblages of pyroxenite and gabbro comprise tellurides, arsenides, and various Pd minerals, as well as native gold and Au-Ag alloy. An indicative Pd/Ir ratio in a succession dunite-chromitite-gabbro increases from 0.04 to 148 with a maximum value of ~5000 in massive sulfide ore of the Volkovsky that is attributable to the contrasting magma compositions defining chromite vs sulfide controls over PGE concentration. • Three PGE mineralization styles are linked to specific lithologies in the Ural-Alaskan type complexes. • Three types of PGE patterns (M-, W-shaped and Ir-Rh ± Pt) are typical of dunite and chromitite. • Pyroxenite and gabbro show sulfide-controlled patterns with enrichment in Au and Pd. • Platinum-group mineral assemblages correlate to the PGE + Au distribution patterns. [ABSTRACT FROM AUTHOR]

This study is aimed at substantiating the prospects of the Pitkäranta Mining District for indium, assessing its resources and elucidating the mineralogical and geochemical features of the distribution of indium in ores. The skarn deposits genetically related to the Salmi anorthosite-rapakivi granite batholith of Early Riphean age were studied. The deposits were divided into two groups, depending on the degree of the greisen alteration of skarns: 1) Sn-Zn-Cu-Fe deposits (the Old Ore Field, Kitelä, Hopunlampi, Heposelkä and Kulismajoki) with little or no greisenization and 2) Be-Sn-Zn deposits with fluorite and magnetite (the New Ore Field, Lupikko, Uksa and Ristiniemi) with well-defined greisenization. Deposits of group 1 are located in the external zone of the Salmi Batholith with a steeply plunging roof (Kitelä), and deposits of group 2 commonly lie above Li F granite domes unexposed by erosion, and are spatially associated with the dykes of these granites and stockscheiders. The distribution of In and associated elements in skarn ores and major ore minerals (sphalerite, chalcopyrite, magnetite and cassiterite) were studied by ICP MS, LA ICP MS and electron probe microanalysis. A total of over 200 samples were analyzed. The results obtained show that In is closely associated geochemically with Zn and Cd, less closely with Cu, Bi and Te is not associated practically with Mo, W, As, Sn and Ag. The content of In in ores from various mines varies from <1 ppm to 0.33 %, and the average In content is 66 ppm. These variations are mainly due to different sphalerite contents in ores and the degree of manifestation of propylitic and greisen alteration of ore-bearing skarns. The main indium-bearing mineral is sphalerite (average In content is 1927 ppm). Other high-In minerals (stannoidite and mawsonite) are uncommon (<0.01 %) and, therefore, do not markedly affect the In balance in ore. The same applies with rare exception to roquesite, the only indium's mineral known here. In-richest (up to 1.5 %) sphalerites with 3–6 % Fe, up to 300–400 ppm Mn and 0.1–0.2 % Co were identified in ore mineral associations of propylitized skarns, which contain no or small amounts of chalcopyrite. Sphalerite-chalcopyrite association is characteristic of roquesite. It occurs mainly in low-tin aposkarn greisens with abundant arsenopyrite-löllingite-sphalerite mineralization. The formation of roquesite seems to have been supported by indium, which was released upon the decomposition of its solid solutions in chalcopyrite and sphalerite and upon the hydrothermal-temperature effect of the late intrusion phases of the Salmi Batholith, Li F granites, on ores. The indium distribution pattern in sphalerite, which is also rich Cd, Ag and Au, shows that roquesite-free propylitized skarns with Sn-Zn-Fe mineralization have the greatest potential for indium and these metals in the zones where the roof of the Salmi Batholith plunges steeply (40–50°) and Li F granites do not occur (Kitelä, Kulismajoki and Hopunlampi deposits). Predicted indium resources in the sphalerite ores of the Pitkäranta Mining District are estimated at 1585–2536 t (as shown by various calculations), cadmium resources at 18424 t, silver resources at 226 t and gold resources at 2 t. • LA-ICP-MS was used to determine In and trace elements in sphalerite from skarns. • The main indium-carrier mineral in skarns of Pitkäranta Mining District is sphalerite. • Roquesite does not contribute substantially to In balance in the ores. • Great exploration potential for In resources is suggested in Pitkäranta Mining District. [ABSTRACT FROM AUTHOR]

The year 2013 marked the 150th anniversary of the birth of the great Russian scientist Vladimir Ivanovich Vernadsky (1863–1945). Vernadsky is considered to be one of the architects of geochemistry and the founder of biogeochemistry. He defined the scientific and philosophical terms biosphere and noosphere, is the intellectual pioneer of the environmental sciences and is the leading protagonist of sustainable development. He was the first geoscientist to merge biological and geological sciences to emphasize the complexity of natural processes and interactions. Despite being regarded as one of the greatest scientists in Russia, his enormous achievements have only recently been recognized internationally. The following biographical–historical account was compiled by the Geoscience Working Group of the Leibniz-Sozietät based in Berlin, Germany. The project paid particular attention to Vernadsky's achievements in mineralogy and geochemistry and his importance in the development of geochemistry in Germany. Vernadsky started his scientific career as a mineralogist but soon dedicated himself to studying the distribution and migration of chemical elements in the Earth's crust. He soon recognized the role of living matter in transforming and utilizing solar energy and as a geological agent, studied the importance of living matter in the chemical evolution of the lithosphere, hydrosphere and atmosphere. He established biogeochemistry as a new scientific discipline and was the first scientist to promote research into the geochemistry of the hydrosphere and, therewith, of marine geochemistry. In the last years of his life he developed concepts regarding the geological impact of mankind, proposing that mankind is a geological factor affecting and changing the natural environment. He was also an extraordinary manager of science and teaching. Together with a large group of colleagues, he revolutionized university teaching and academic research and guided successful students including Fersman, Chlopin, and Vinogradov. He influenced science internationally by undertaking visits to Germany, Italy, Austria and France. Important impacts on the development of geochemistry in Germany were Vernadsky's and Fersman's presentations at the Russische Naturforscherwoche (Russian natural science week) in Berlin in 1927. As a result of this meeting, the German edition of Vernadsky's Essays in Geochemistry was published, the first German textbook in geochemistry. [ABSTRACT FROM AUTHOR]

Abstract: The paper gives landscape-geochemical characteristics (processes of migration, dispersion and concentrations of elements in soils) of the Russian part of the Amur Basin. The impact of geographic factors on the formation of soil-geochemical systems is revealed and mechanisms of moisture interactions with the soil system are described. The spatial heterogeneity of chemical element concentrations in background soils is viewed as a function of the migration activity of elements. The role of iron in the regional geochemical background formation is revealed. Migration conditions of indicator elements and levels of their activity are discussed. The map Landscape-Geochemical Zoning of the Amur Basin, scale (1:2,500,000) was created based on ArcGis 10 (ArcMap). The map reflects soil-geochemical migration zones by indicator elements in soils. [Copyright &y& Elsevier]

Abstract: Herein some results of comparative researches to determine the parameters of selenium migration in meadow biogeocenoses of East Meshchera and East Transbaikalia are presented. The parameters of selenium mobility in soils (i.e., the element total content, plant-accumulation coefficient (Kb) and/or mobile form ratio) in Urov biogeochemical provinces of the East Transbaikalia are quite comparable to the element migration parameters found in selenium-deficient landscapes of the same area. Selenium mobility indices and ecological status are significantly higher for meadow biogeocenoses of the East Meshchera (Moscow Region) and also for limestone soils. [ABSTRACT FROM AUTHOR]

A strong correlation between the chemical composition of kimberlites and their diamond grade has been established using statistical methods. The investigation is based upon major element analyses of kimberlite samples, from which xenoliths have been removed. The samples represent highly diamondiferous, moderately diamondiferous, slightly diamondiferous and diamond-free rocks from diatremes of the Yakutian Kimberlite Province. In total, the investigation comprises 3792 whole-rock analyses and 1176 determinations of diamond grade. By means of correlation analysis, the kimberlite chemical analyses were subdivided into 113 clusters. Regression analysis was carried out between mean major element oxide concentrations of the clusters and the corresponding average values of diamond contents. The combined use of the regression method with a break-point and generalized nonlinear discrimination analysis has allowed to correctly estimate the average diamond grade of kimberlite clusters in more than 85–90% of the cases. The established statistical relations are convincingly justified from a petrological point of view. The reliable petrochemical description of kimberlite variety, based on averaging 25–30 whole-rock analyses or on analyzing of a sample obtained as a result of sequential quartering of a much larger sample, allows to estimate safely its diamond grade using major oxide contents. The method has worldwide application potential. [Copyright &y& Elsevier]