Abstract. The coupled biogeochemical cycles of iron and sulfur are central to the long-term evolution Earth's oceans. For instance, before development a persistently oxygenated deep ocean, ocean interior likely alternated between states buffered by reduced (“euxinic”) (“ferruginous”), with important implications for hence bioavailability dissolved (and phosphate). Even after atmospheric oxygen ...

Abstract— Based on Sm–Nd data, a crustal source of iron-ore fluid was substantiated and the probability age estimation for hydrothermal–metasomatic siderite Bakal Group, Southern Urals, shown first time. The εNd (Т) values (from –13.4 to –17.6) plot in field Riphean shale not Precambrian rift gabbro granite this region. obtained is 970 ± 40 Ma, which consistent with Pb–Pb from major ore phase (...

The paper considers the results of application dry magnetic separation on samples ferruginous quartzites Kostomuksha ore field, represented by refractory ore, free-milling and their mixture. assessment influence texture technological parameters indicates insignificant changes: yield non-magnetic product varies from 12.4 to 13.5%, Fetotal content in increases 1.11–1.14 times. A decrease at least...