The paper deals with the commodity flows (production, import, export, consumption, prices) of manganese, chromium, silicon, vanadium, niobium, molybdenum, tungsten, titanium and nickel ferroalloys in dynamics from 2000 to 2019 throughout Russia. also specifies groups ferroalloys: import-dependent (silicomanganese, metallic ferroniobium), export-oriented (ferrosilicon, ferrochrome, ferrovanadium...

Abstract The isotopic composition of seawater provides valuable information on how the Earth system has evolved. Here we present stable tungsten (δ186/184W) recorded in three ferromanganese (Fe-Mn) crusts spanning past 80 million years Pacific. δ186/184W Fe-Mn displays a pronounced decrease ∼0.2‰ from 60 Ma to 40 followed by value ∼0‰ since ca. Ma. Multiple lines evidence indicate an invariable...

The chemical and isotopic compositions of oceanic biogenic and authigenic minerals contain invaluable information on the evolution of seawater, hence on the history of interaction between tectonics, climate, ocean circulation, and the evolution of life. Important advances and greater understanding of (a) key minor and trace element cycles with various residence times, (b) isotopic sources and s...

A procedure was developed for the determination of element distributions in cross-sections of ferromanganese concretions using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The effects of carrier flow rates, rf forward power, ablation energy, ablation spot size, repetition rate and number of shots per point on analyte intensity were studied. It is shown that different...

Oceanic oxygen levels are projected to drop in certain areas due to warming climate, but the net effect to the overall ocean redox state is difficult to predict. Here we measured the “stable” uranium isotope composition (U/U) in globally representative hydrogenous ferromanganese crusts in order to reconstruct the redox evolution of the global ocean throughout the Cenozoic. Samples averaging 3 M...

Ocean acidification has been predicted to reduce the ability of marine organisms to produce carbonate skeletons, threatening their long-term viability and severely impacting marine ecosystems. Corals, as ecosystem engineers, have been identified as particularly vulnerable and important. To determine the sensitivity of corals and allied taxa to long-term exposure to very low carbonate concentrat...

Ferromanganese (Fe-Mn) sedimentary layers and nodules occur at different depths within sediments deep basins ridges of Lake Baikal. We studied Fe-Mn host recovered the slope Bolshoy Ushkany Island. Layer-by-layer 230Th/U dating analysis determined initial age nodule formation scattered in as 96 ± 5–131 8 Ka. The distribution profiles main ions pore waters sediment are similar to those observed ...

Our understanding of the up to 7 orders magnitude partitioning thallium (Tl) between seawater and ferromanganese (FeMn) deposits rests upon two foundations: (1) being able quantify Tl(I)/Tl(III) ratio that reflects extent oxidative scavenging Tl by vernadite (?-MnO2), principle manganate mineral in oxic suboxic environments, (2) determine sorption sites bonding environments Tl(I) Tl(III) comple...