Influence of goethite nanophase on rare-earth element patterns …
网页2024年5月20日 · Some marine authigenic phosphates show a “bell-shaped” pattern with an enrichment of the middle REEs (MREEs; Nd Ho), while others exhibit a “modern seawater-like” pattern characterized by a strong depletion in cerium and an enrichment in heavy REEs (Er Lu, Y, and Sc).
The mobility of thorium, uranium and rare earth elements from …
网页2022年11月1日 · Secondary colloform phosphate-rich goethite minerals have been identified by EPMA in one intensely brecciated and weathered shale (sample L26-A, Figs. 3 F, 4D–E), rich in La 2 O 3 (440 μg/g) and Ce 2 O 3 (680 μg/g) (Supp. Material Table S2).
Mineralogical, chemical, and physical metallurgical characteristics …
网页2022年1月1日 · The three most common iron ore minerals are magnetite (Fe 3 O 4), hematite (Fe 2 O 3) and goethite (FeOOH), with the most common forms of goethite being brown, yellow ochreous, and dark brown vitreous goethite. Quartz, kaolinite and gibbsite are the most common gangue minerals.
Goethite Morphology and Composition in Banded Iron Formation…
网页2008年8月8日 · These goethite morphologies develop where iron ore is associated with shale formation (aluminous rock). The nodular type is always rich in phosphorus and when the phosphorus content exceeds 5% it may be termed phospho-goethite.
Automated optical image analysis of goethitic iron ores
网页2022年3月1日 · The article demonstrates the capability of OIA software Mineral4/Recognition4 to characterise goethitic iron ores. Characterisation includes identification of the different types of goethite, hydrohematite and gangue materials such as quartz and kaolinite. XRD and XRF analysis results are compared with those from OIA.
Susquehanna Shale Hills - Critical Zone
网页Some euhedral goethite grains near the fractures retain the pyrite cores, clearly demonstrating the pseudomorphic transformation of pyrite into goethite. We are pursuing FIB-SEM and TEM studies of the pyrite-goethite interface to determine the mechanism of the pseudomorphic transformation.
Paleo‐stratigraphic permeability anisotropy controls supergene …
网页This goethite enrichment is an absolute accrual of iron and an almost elimination of the gangue chemical elements without the loss of the original BIF mineral textures. The upper part of the supergene mimetic enrichment is in turn …
The mobility of thorium, uranium and rare earth elements from …
网页2022年8月1日 · Sampled precipitates were mainly schwertmannite (Fe8O8(OH)8-2x (SO4)xO16•nH2O) and goethite (α–Fe³⁺O(OH)) that showed an enrichment of Th (up to 798 μg/g) and REY, due to the presence of ...
网页iron (hydr)oxides are goethite. In addition, where rocks are fractured beneath the water table under the ridge, pyrite is also observed to be depleted around fractures. Some euhedral goethite grains near the fractures retain the pyrite cores, clearly demonstrating the pseudomorphic transformation of pyrite into goethite.
Textural complications of banded iron formation and the potential ...
网页2023年9月13日 · The occurrence of ferrous and ferric iron minerals, including magnetite, martite, and goethite, has shed more light on the possible exploitation of the texturally complicated BIF as a precursor...
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