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Article
Rare Earth Elements in Iron Oxyhydroxides from Biofilms Containing the Fe-Oxidizing Bacteria
Iron oxyhydroxides extracted from present-day biofilms with the Fe-oxidizing bacteria Arthrobacter spp., Gallionella spp., and Leptothrix ochracea in the northwest of the East European Platform display a signific...
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Article
Sulfur in the Tephra of the ca. 1500 BP Opala Eruption, Kamchatka
Sulfur-containing ejecta of Plinian-type eruptions can be transported to great distances in gas pores of ash particles. The mean concentration of sulfur in the rhyolite tephra of the ca. 1500 BP Opala eruption...
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Article
Bacterial Remains in the Lower Proterozoic Red-Colored Quartzites
The discovery of numerous bacterial remains (including those morphologically similar to modern ironbacteria) in the lower Proterozoic red-colored quartzites of Shoksha, Karelia, and Bolshoy Tyuters Island of t...
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Article
Carbon Isotope Composition and Concentration of Fe-Group Elements in the Sedimentary Organic Matter from Rocks of Different Ages
The Fe/Co ratio (ppm) in the kerogen from different-aged clastic sediments (Early Proterozoic–Mesozoic) varies from 17 to 4100, and δ13C value varies from –14.8 to –32.6‰. The relationship between Fe/Co and δ13C ...
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Article
Bacterial paleontology of the Neoarchean banded iron formations of Karelia and the Kola Peninsula
Probable microfossils, presumably of bacterial origin, were found in the banded iron formations of Karelia and the Kola Peninsula. The age of these formations is 2.7–2.8 Ga. Based on the organic carbon content...
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Article
Isotope and microelement systematics of Gallionella sp.-containing bacterial mats from the northwest of the East European Platform
Microelement composition of Gallionella sp.-containing bacterial mats from the environs of St. Petersburg and isotope composition of organic carbon, strontium, and neodymium from these mats have been determined. ...
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Article
Cyanobacteria(?) in iron banded formations of the Kursk magnetic anomaly
Fossilized cyanobacteria(?) represented by trichomes enclosed in common sheaths were detected in early Proterozoic iron banded formations of the Kursk magnetic anomaly (limonite–martite ores of the Lebedinsky ...
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Article
Rare earth elements and Rb–Sr and Sm–Nd systematics in the peat bog iron ore and moss of the NW East European Platform
Spectra of the REE distribution in the Quaternary–Recent peat bog ore of southern Karelia and Leningrad region are characterized by LaN/YbN < 1.0, presence of positive Eu and negative Ce anomalies, and higher Y e...
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Article
Isotope composition of neodymium in neo-Archean banded iron formations of Karelia and Kola Peninsula
Studies of three deposits of neo-Archean banded iron formations from the West Karelian domain (the Kostomuksha deposit) and from the Central Kola block (the Olenegorsk and Kirovogorsk deposits) showed a pronou...
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Article
Carbon isotope signatures of Neoproterozoic and Early Cambrian organic fossils from Siberian and East European platforms
Study of carbon isotopic composition of micro- and macrofossils and dissipated sedimentary matter (kerogens) extracted by acid maceration from the clay shales from three Riphean, Vendian, and Cambrian sections...
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Article
Isotope-geochemical systematics of gold-bearing biogenic apatites from Lower Paleozoic deposits of Baltoscandia
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Article
K+/Na+ in the animal extracellular fluid at weathering of granitoids and problem of the origin of life
Leaching of granitoids of the paleoproterozoic age was performed from several seconds to 360 days in water solutions (pH < 6.0) in the oxygen or argon medium. Under these conditions the entrance of K+ into the so...
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Article
Mobility of cerium in the 2.8-2.1 Ga exogenous environments of the Baltic Shield: Data on weathering profiles and sedimentary carbonates
The absence of Ce anomaly and significant positive correlation between Ce and Fe in the weathering profiles and sedimentary carbonate rocks of the Baltic Shield with an age of 2.8–2.1 Ga indicate that Fe3+ was th...
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Article
Fractionation of rare earth elements in the acid treatment of granitoids
The relative enrichment of authigenic clay minerals with heavy rare earth elements (HREE) in Paleoproterozoic weathering profiles on the Baltic Shield is related to the presence of strong acids in drainage wat...
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Article
Gold in Vendian-Cambrian organic macrofossils of the East European platform
According to the neutron activation analysis (NAA) data, the average Au content makes up 0.004 μg/g in sabelliditid tubes, 0.08 μg/g in vendotaenid ribbon remains, and 0.28 μg/g (the maximal value) in sapropel...
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Article
Gold in lower Paleozoic conodont elements of Baltoscandia
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Article
Redistribution of Au in volcanic ashes in the course of their postsedimentary alterations
The redistribution of Au in Late Precambrian volcanic ashes from the Vendian section of the East European Platform and the Sinian section of the South China Platform is characterized by high Au concentration (...
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Article
The content of gold in Lower Paleozoic phosphatized biogenic remains in Baltoscandia
According to instrumental neutron activation analysis (INAA) data, the average content of Au in conodont elements and phosphate brachiopod shells from Lower Paleozoic sections in Baltoscandia is 4.9 and 0.79 μ...
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Article
The content of gold in Vendian-Cambrian phosphorite concretions from the East European Platform
High Au contents in phosphorite concretions and Vendian-Cambrian enclosing shales are attributed to the concentration function of microbial biota of Precambrian epiplatformal basins. Microorganisms and organic...
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Article
Alkali earth elements in Vendian-Cambrian clayey rocks, the East European Platform
Low Sr and Ca contents in fine-grained terrigenous rocks of the Vendian sedimentary cover in the East European Platform may be related to the following reasons: (1) the absence of authigenic carbonates in Vend...
