REE(III) adsorption onto Mn dioxide (δ-MnO2) and Fe oxyhydroxide: Ce(III) oxidation by δ-MnO2

Ohta, Atsuyuki; Kawabe, Iwao

doi:10.1016/s0016-7037(00)00578-0

Cited by 391 publications

(254 citation statements)

References 25 publications

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“…The negative correlation coefficients between P and REEs (r = -0.15 to -0.44) indicates that the P-bearing minerals did not play any role for concentration of lanthanides. Although De Carlo et al (1998), Bau (1999), and Ohta and Kawabe (2001) reported that there is a close relationship between Ce and Fe and Mn in the weathered systems, Ce at Kanigorgeh displays a good correlation only with Mn (r = 0.85), indicating the role of Mn-oxides in fixation of this element. This high correlation coefficient also shows that, analogous to Ce, the variation in redox potential is a key factor for distribution of Mn in this profile (Ma et al, 2007).…”

Section: Mineral Controls On the Ree Distributionmentioning

confidence: 94%

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Abedini

Calagari²

2014

Turkish J Earth Sci

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IntroductionBauxite deposits are formed by alteration and weathering of parent rocks rich in alumino-silicate minerals. These residual deposits are developed principally in tropical to subtropical climatic conditions with annual rainfall exceeding 1.2 m and an average temperature of >22 °C (Bardossy and Aleva, 1990;Mondillo et al., 2011). According to Bardossy and Combes (1999), these deposits are characterized into 3 major groups: lateritic bauxite deposits, karst bauxite deposits, and Tikhvin-type bauxite deposits. The first group is the product of in situ and direct chemical weathering of alumino-silicate rocks lying beneath the surface. The second group is developed on the surface of more or less karstified carbonates (limestone and dolomite) and scarce marls. The third group is formed on the surface of eroded alumino-silicate rocks and is the erosional product of lateritic bauxite deposits. Bardossy (1982), based upon parameters such as morphology and chemical compositions, classified the bauxite deposits into 6 distinct groups: Mediterranean type, Kazakhstan type, Timan type, Salento type, Tulsk type, and Ariege type. Based upon geographical situations, these deposits occurred in 7 belts throughout the world: the northern Mediterranean coast, Caribbean basin, Urals-Siberia-Central Asia, East Asia, Irano-Himalaya, Southwest Pacific, and North America.During the last few decades, geochemical investigations proved to have practical applications for determination of various aspects of formation and evolution of bauxite deposits such as the type of parent rocks; the roles of diagenetic, epigenetic, and supergene processes in connection to ore-forming mechanisms; physicochemical conditions of the environment of the ore formation (e.g., pH, Eh, intensity of draining, and climate); the mineral controls on distribution, mobilization, and fractionation of elements [particularly trace and rare earth elements (REEs)] in the course of bauxitization; and tectonometamorphic evolutions (Özlü,

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Section: Mineral Controls On the Ree Distributionmentioning

confidence: 94%

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Abedini

Calagari²

2014

Turkish J Earth Sci

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“…These authors concluded that Ce in the upland groundwater was oxidized to Ce(IV) and removed either by direct precipitation or by oxidative scavenging on the surfaces of Fe and Mn oxyhydroxides forming in the soil. Soils from various modern climatic zones typically exhibit Ce enrichment, which is commonly ascribed to either: 1) oxidation of dissolved Ce(III) and formation of cerianite (CeO 2 ), commonly as globules adhering to minerals in Mn oxide-rich areas; or 2) oxidation and scavenging of dissolved Ce(III) by Mn oxyhydroxides (Rankin and Childs, 1976;Lei et al, 1986;Marsh, 1991;Koppi et al, 1996;Braun et al, 1998;Bau, 1999;Ohta and Kawabe, 2001;Ji et al, 2004). Such precipitation processes lead to negative Ce anomalies in both surface water (Sholkovitz, 1995) and groundwater (Smedley, 1991;Braun et al, 1998;Dia et al, 2000;Compton et al, 2003).…”

Section: Rare Earth Elementsmentioning

confidence: 99%

Geochemistry of Paleoproterozoic Gunflint Formation carbonate: Implications for hydrosphere-atmosphere evolution

Fralick

Planavsky

Burton

et al. 2017

Precambrian Research

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The ~1880 Ma Gunflint Formation has played a critical role in shaping our view of the evolution of the Precambrian biosphere and the redox state of Earth's early oceans.Herein we present a study of the petrology and geochemistry of calcic grainstones and stromatolitic limestones present at the very top of the Gunflint Formation and compare them with underlying ankeritic grainstones that dominate the shore-proximal portion of the basin. Meteoric calcite cements in the upper limestones formed prior to the unit being brecciated and/or buried by debris carried by the blast cloud from the 1850 Ma Sudbury impact event. The intraclastic grains and cements in the limestone are highly enriched in V, Cr, U and REEs, with REE patterns similar to those of modern groundwater. Cr isotopes have a distinctly positive signature in most samples indicating formation of oxidized, hexavalent Cr during subaerial weathering. These redox-sensitive metals were transported in oxygenated groundwater and precipitated where the fluid encountered reducing conditions. In contrast, the underlying ankeritic marine grainstones have REE patterns similar to those of some modern-day venting hydrothermal fluids and earliest Paleoproterozoic seawater. This work suggests that significant levels of oxygen existed in the atmosphere at the time, whereas, even shallow areas of the world ocean remained very oxygen-deficient. The contrast in redox state of anoxic shallow-marine water verses oxic groundwater was probably linked to strong sub-seafloor hydrothermal circulation and extensive upwelling onto shallow shelves, which could have sustained widespread marine anoxia. More broadly, our study highlights the importance of investigating and understanding lateral geochemical gradients, and the flux rates that control them, in shallow paleomarine settings.

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“…The shallow water of Coral Sea has Ce anomaly ~-0.18 whereas its deeper waters exhibit pronounced negative anomalies (<-1.0). Ce oxidation has been attributed to surface catalysis on Mn-oxyhydroxide in oxic condition (Bau, 1999) or to the direct oxidation of Ce 3+ (aq) by δ-MnO 2 (Ohta and Kawabe, 2001). However, Moffett (1990Moffett ( , 1994) advocated microbially mediated oxidation of Ce as more effective than abiogenic processes of Ce removal.…”

Section: Cerium Anomalymentioning

confidence: 99%

Characteristics of rare earth element abundances in shallow marine continental platform carbonates of Late Neoproterozoic successions from India.

et al. 2003

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We have studied the REE distribution in shallow marine continental platform carbonates belonging to two late Neoproterozoic basins of India. Their REE abundance patterns normalized by chondrite display well defined W-type tetrad effect. Based on chondrite-normalized Gd/Ho, La/Nd ratios, the REE abundance patterns have been classified into three groups. (Y/Ho) and (Y/Dy) concentration ratios reflect a combined effect of Y fractionation relative to neighboring trivalent REEs during carbonate precipitation from seawater and influence of continental contributions with chondritic ratios. Negative Ce anomalies recorded in Krol and Bilara carbonates resembles the Ce anomaly reported from shallow marine waters. However, absence of Ce anomaly and distinct positive anomalies in some of our carbonate samples reflect post-depositional redox condition related to Ce mobilization and preferential enrichment during early diagenesis. Variations in the REE abundance patterns may be attributed to contamination with terrigenous particulates having shale like REE abundances and post-depositional early diagenetic processes.

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REE(III) adsorption onto Mn dioxide (δ-MnO2) and Fe oxyhydroxide: Ce(III) oxidation by δ-MnO2

Cited by 391 publications

References 25 publications

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

REE geochemical characteristics of titanium-rich bauxites: the Permian Kanigorgeh horizon, NW Iran

Geochemistry of Paleoproterozoic Gunflint Formation carbonate: Implications for hydrosphere-atmosphere evolution

Characteristics of rare earth element abundances in shallow marine continental platform carbonates of Late Neoproterozoic successions from India.

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