Petrography and Geochemistry of the Carboniferous Ortokarnash Manganese Deposit in the Western Kunlun Mountains, Xinjiang Province, China: Implications for the Depositional Environment and the Origin of Mineralization

2020 ◽  
Vol 115 (7) ◽  
pp. 1559-1588
Author(s):  
Bang-Lu Zhang ◽  
Chang-Le Wang ◽  
Leslie J. Robbins ◽  
Lian-Chang Zhang ◽  
Kurt O. Konhauser ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Water Column ◽  
Manganese Carbonate ◽  
Manganese Ore ◽  
Burial Diagenesis ◽  
Kunlun Mountains ◽  
Western Kunlun ◽  
Heavy Rare Earth Elements ◽  
West Kunlun

Abstract The Upper Carboniferous Ortokarnash manganese ore deposit in the West Kunlun orogenic belt of the Xinjiang province in China is hosted in the Kalaatehe Formation. The latter is composed of three members: (1) the 1st Member is a volcanic breccia limestone, (2) the 2nd Member is a sandy limestone, and (3) the 3rd Member is a dark gray to black marlstone containing the manganese carbonate mineralization, which, in turn, is overlain by sandy and micritic limestone. This sequence represents a single transgression-regression cycle, with the manganese deposition occurring during the highstand systems tract. Geochemical features of the rare earth elements (REE+Y) in the Kalaatehe Formation suggest that both the manganese ore and associated rocks were generally deposited under an oxic water column with Post-Archean Australian Shale (PAAS)-normalized REE+Y patterns displaying characteristics of modern seawater (e.g., light REE depletion and negative Ce anomalies). The manganese ore is dominated by fine-grained rhodochrosite (MnCO3), dispersed in Mn-rich silicates (e.g., friedelite and chlorite), and trace quantities of alabandite (MnS) and pyrolusite (MnO2). The replacement of pyrolusite by rhodochrosite suggests that the initial manganese precipitates were Mn(IV)-oxides. Precipitation within an oxic water column is supported by shale-normalized REE+Y patterns from the carbonate ores that are characterized by large positive Ce (>3.0) anomalies, negative Y (~0.7) anomalies, low Y/Ho ratios (~20), and a lack of fractionation between the light and heavy rare earth elements ((Nd/Yb)PAAS ~0.9). The manganese carbonate ores are also 13C-depleted, further suggesting that the Mn(II) carbonates formed as a result of Mn(III/IV)-oxide reduction during burial diagenesis.

scholarly journals Intrinsically weak magnetic anisotropy of cerium in potential hard-magnetic intermetallics

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Anna Galler ◽  
Semih Ener ◽  
Fernando Maccari ◽  
Imants Dirba ◽  
Konstantin P. Skokov ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Magnetic Anisotropy ◽  
High Performance ◽  
Kondo Effect ◽  
Quantitative Description ◽  
Many Body ◽  
Heavy Rare Earth Elements ◽  
Fe Intermetallics ◽  
Full Temperature

AbstractCerium-based intermetallics are currently attracting much interest as a possible alternative to existing high-performance magnets containing scarce heavy rare-earth elements. However, the intrinsic magnetic properties of Ce in these systems are poorly understood due to the difficulty of a quantitative description of the Kondo effect, a many-body phenomenon where conduction electrons screen out the Ce-4f moment. Here, we show that the Ce-4f shell in Ce–Fe intermetallics is partially Kondo screened. The Kondo scale is dramatically enhanced by nitrogen interstitials suppressing the Ce-4f contribution to the magnetic anisotropy, in striking contrast to the effect of nitrogenation in isostructural intermetallics containing other rare-earth elements. We determine the full temperature dependence of the Ce-4f single-ion anisotropy and show that even unscreened Ce-4f moments contribute little to the room-temperature intrinsic magnetic hardness. Our study thus establishes fundamental constraints on the potential of cerium-based permanent magnet intermetallics.

Selective recovery of heavy rare earth elements from apatite with an adsorbent bearing immobilized tridentate amido ligands

2016 ◽  
Vol 159 ◽  
pp. 157-160 ◽  
Author(s):  
Takeshi Ogata ◽  
Hirokazu Narita ◽  
Mikiya Tanaka ◽  
Mihoko Hoshino ◽  
Yoshiaki Kon ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Heavy Rare Earth ◽  
Amido Ligands ◽  
Selective Recovery ◽  
Heavy Rare Earth Elements

Geochemical characteristics and geologic significance of rare earth elements in oil shale of the Yan’an Formation in the Tanshan area, in the Liupanshan Basin, China

2021 ◽  
pp. 1-41
Author(s):  
Lianfu Hai ◽  
Qinghai Xu ◽  
Caixia Mu ◽  
Rui Tao ◽  
Lei Wang ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Oil Shale ◽  
Sedimentary Environment ◽  
Moderate Degree ◽  
Material Source ◽  
Icp Ms ◽  
Ree Distribution ◽  
Heavy Rare Earth Elements ◽  
Degree Of Differentiation

In the Tanshan area, which is at the Liupanshui Basin, abundant oil shale resources are associated with coals. We analyzed the cores, geochemistry of rare earth elements (REE) and trace element of oil shale with ICP-MS technology to define the palaeo-sedimentary environment, material source and geological significance of oil shale in this area. The results of the summed compositions of REE, and the total REE contents (SREE), in the Yan'an Formation oil shale are slightly higher than the global average of the composition of the upper continental crustal (UCC) and are lower than that of North American shales. The REE distribution pattern is characterized by right-inclined enrichment of light rare earth elements (LREE) and relative loss of heavy rare earth elements (HREE), which reflects the characteristics of crustal source deposition. There is a moderate degree of differentiation among LREE, while the differences among HREE are not obvious. The dEu values show a weak negative anomaly and the dCe values show no anomaly, which are generally consistent with the distribution of REE in the upper crust. The characteristics of REE and trace elements indicate that the oil shale formed in an oxygen-poor reducing environment and that the paleoclimatic conditions were relatively warm and humid. The degree of differentiation of REE indicates that the sedimentation rate in the study area was low, which reflected the characteristics of relatively deep sedimentary water bodies and distant source areas. The results also proved that the source rock mainly consisted of calcareous mudstone, and a small amount of granite was also mixed in.

scholarly journals Effect of acid mine drainage on dissolved rare earth elements geochemistry along a fluvial–estuarine system: the Tinto-Odiel Estuary (S.W. Spain)

2012 ◽  
Vol 43 (3) ◽  
pp. 262-274 ◽  
Author(s):  
J. Borrego ◽  
B. Carro ◽  
N. López-González ◽  
J. de la Rosa ◽  
J. A. Grande ◽  
...  
Keyword(s):  
Rare Earth ◽  
Acid Mine Drainage ◽  
Rare Earth Elements ◽  
Mine Drainage ◽  
Drainage System ◽  
Estuarine System ◽  
Mixing Zone ◽  
Heavy Rare Earth ◽  
Acid Mine ◽  
Heavy Rare Earth Elements

The concentration of rare earth elements together with Sc, Y, and U, as well as rare earth elements fractionation patterns, in the water of an affected acid mine drainage system were investigated. Significant dissolved concentrations of the studied elements were observed in the fluvial sector of this estuary system (Sc ∼ 31 μg L−1, Y ∼ 187 μg L−1, U ∼ 41 μg L−1, Σ rare earth elements ∼621 μg L−1), with pH values below 2.7. In the mixing zone of the estuary, concentrations are lower (Sc ∼ 2.1 μg L−1; Y ∼ 16.7 μg L−1; U ∼ 4.8 μg L−1; Σ rare earth elements ∼65.3 μg L−1) and show a strong longitudinal gradient. The largest rare earth elements removal occurs in the medium-chlorinity zone and it becomes extreme for heavy rare earth elements, as observed for Sc. Samples of the mixing zone show a North American Shale normalized pattern similar to the fluvial zone water, while the samples located in the zone with pH between 6.5 and 7.7 show a depletion of light rare earth elements relative to middle rare earth elements and heavy rare earth elements, similar to that observed in samples of the marine estuary.

scholarly journals Separation and Adsorption-Desorption Characteristics of Heavy Rare Earth Elements (Gd, Tb, Dy) using P507 Resin

2016 ◽  
Vol 25 (4) ◽  
pp. 60-67
Author(s):  
Sungeun Lee ◽  
Joung Woon Kim ◽  
Jong Hyuk Jeon ◽  
Hong Myeong Jun ◽  
Jin Young Lee ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Heavy Rare Earth ◽  
Heavy Rare Earth Elements ◽  
Adsorption Desorption

High specific surface 1-(2-pyridylazo) 2-naphthol (PAN) modified Carbon-based silicon film with cellulose nanocrystalline structure for efficient adsorption of rare earth elements

2021 ◽  
Author(s):  
Bin Wang ◽  
Yuzhe Zhang ◽  
Wen Sun ◽  
Xudong Zheng ◽  
Zhongyu Li
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Specific Surface ◽  
Cellulose Nanocrystals ◽  
Silicon Film ◽  
Nanocrystalline Structure ◽  
Heavy Rare Earth ◽  
Beneficial Result ◽  
Waste Products ◽  
Heavy Rare Earth Elements

The recovery of rare earth elements, especially heavy rare earth elements, from rare earth waste products has a high economic and environmental beneficial result. In this paper, cellulose nanocrystals used...

Petrogenesis of the Upper Cretaceous volcanism in the Kefken region, Western Pontides, NW Turkey

2021 ◽  
Author(s):  
Turgut Duzman ◽  
Ezgi Sağlam ◽  
Aral I. Okay
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Partial Melting ◽  
Upper Cretaceous ◽  
Volcanic Rocks ◽  
Early Eocene ◽  
Heavy Rare Earth ◽  
Heavy Rare Earth Elements ◽  
Cretaceous Volcanism ◽  
Oceanic Slab

<p>The Upper Cretaceous volcanic and volcaniclastic rocks crop out along the Black Sea coastline in Turkey. They are part of a magmatic arc that formed as a result of northward subduction of the Tethys ocean beneath the southern margin of Laurasia. The lower part of the Upper Cretaceous volcanism in the Kefken region, 100 km northeast of Istanbul, is represented by basaltic andesites, andesites, agglomerates and tuffs, which have yielded Late Cretaceous (Campanian, ca. 83 Ma) U-Pb zircon ages. The volcanic and volcanoclastic rocks are stratigraphically overlain by shallow to deep marine limestones, which range in age from Late Campanian to Early Eocene.  Geochemically, basaltic andesites and andesites display negative anomalies in Nb, Ta and Ti, enrichment in large ion lithophile elements (LILE) relative to high field strength elements (HFSE). Light rare earth elements (LREE) show slightly enrichment relative to heavy rare earth elements (La<sub>cn</sub>/Yb<sub>cn</sub> =2.51-3.63) and there are slight negative Eu anomalies (Eu/Eu* = 0.71-0.95) in basaltic andesite and andesite samples. The geochemical data indicate that Campanian volcanic rocks were derived from the partial melting of the mantle wedge induced by hydrous fluids released by dehydration of the subducted oceanic slab.</p><p>There is also a horizon of volcanic rocks, about 230 m thick, within the Late Campanian-Early Eocene limestone sequence.  This volcanic horizon, which consists of pillow basalts, porphyritic basalts,  andesites and dacites, is of Maastrichtian age based on paleontological data from the intra-pillow sediments and U-Pb zircon ages from the andesites and dacites (72-68 Ma).  The Maastrichtian andesites and dacites are geochemically distinct from the Campanian volcanic rocks. They show distinct adakite-like geochemical signatures with high ratios of Sr/Y (>85.5), high La<sub>cn</sub>/Yb<sub>cn </sub>(16.4-23.7) ratios, low content of Y (7.4-8.6 ppm) and low content of heavy rare-earth elements (HREE). The adakitic rocks most probably formed as a result of partial melting of the subducting oceanic slab under garnet and amphibole stable conditions.</p><p>The Upper Cretaceous arc sequence in the Kefken region shows a change from typical subduction-related magmas to adakitic ones, accompanied by decrease in the volcanism.</p><p> </p><p> </p>

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