Rare-earth element mobility during ore-forming hydrothermal alteration: A case study of Dongping gold deposit Hebei Province, China

2003 ◽  
Vol 22 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Bao Zhiwei ◽  
Zhao Zhenhua
Keyword(s):  
Rare Earth ◽  
Gold Deposit ◽  
Hydrothermal Alteration ◽  
Rare Earth Element ◽  
Earth Element ◽  
Hebei Province ◽  
Element Mobility

Transport and transformation of riverine neodymium isotope and rare earth element signatures in high latitude estuaries: A case study from the Laptev Sea

2017 ◽  
Vol 477 ◽  
pp. 205-217 ◽  
Author(s):  
Georgi Laukert ◽  
Martin Frank ◽  
Dorothea Bauch ◽  
Ed C. Hathorne ◽  
Marcus Gutjahr ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
High Latitude ◽  
Earth Element ◽  
Laptev Sea ◽  
Transport And Transformation ◽  
The Laptev Sea

scholarly journals Rare earth element mobility in and around carbonatites controlled by sodium, potassium, and silica

2020 ◽  
Vol 6 (41) ◽  
pp. eabb6570 ◽  
Author(s):  
Michael Anenburg ◽  
John A. Mavrogenes ◽  
Corinne Frigo ◽  
Frances Wall
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Rare Earth Element ◽  
Earth Element ◽  
Element Mobility ◽  
Sodium Potassium ◽  
Ree Mineralization ◽  
Anionic Species ◽  
Ree Mobility ◽  
Modern Technologies

Carbonatites and associated rocks are the main source of rare earth elements (REEs), metals essential to modern technologies. REE mineralization occurs in hydrothermal assemblages within or near carbonatites, suggesting aqueous transport of REE. We conducted experiments from 1200°C and 1.5 GPa to 200°C and 0.2 GPa using light (La) and heavy (Dy) REE, crystallizing fluorapatite intergrown with calcite through dolomite to ankerite. All experiments contained solutions with anions previously thought to mobilize REE (chloride, fluoride, and carbonate), but REEs were extensively soluble only when alkalis were present. Dysprosium was more soluble than lanthanum when alkali complexed. Addition of silica either traps REE in early crystallizing apatite or negates solubility increases by immobilizing alkalis in silicates. Anionic species such as halogens and carbonates are not sufficient for REE mobility. Additional complexing with alkalis is required for substantial REE transport in and around carbonatites as a precursor for economic grade-mineralization.

Petrological, geochronological, and geochemical potential accounting for continental subduction and exhumation: A case study of felsic granulites from South Altyn Tagh, northwestern China

2020 ◽  
Vol 132 (11-12) ◽  
pp. 2611-2630
Author(s):  
Yunshuai Li ◽  
Jianxin Zhang ◽  
Shengyao Yu ◽  
Yanguang Li ◽  
Hu Guo ◽  
...  
Keyword(s):  
High Pressure ◽  
Rare Earth ◽  
Rare Earth Element ◽  
Earth Element ◽  
Granitic Rocks ◽  
Geodynamic Evolution ◽  
Altyn Tagh ◽  
Rare Earth Element Distribution ◽  
Ultrahigh Temperature

Abstract Deciphering the formation and geodynamic evolution of high-pressure (HP) granulites in a collisional orogeny can provide crucial constraints on the geodynamic evolution of subduction-exhumation. To fully exploit the geodynamic potential of metamorphic rocks, it is necessary to constrain the metamorphic ages, although it is difficult to link zircon and monazite ages to metamorphic evolution. A good case study for understanding these geodynamic processes is felsic granulites in the Bashiwake area, South Altyn Tagh. Petrographic observations suggest that the studied felsic granulites have suffered multi-stage metamorphism, and the distinct metamorphic events were documented by compositional zoning and high Y + heavy rare earth element (HREE) concentrations in the large garnet porphyroblast. Zircon U-Pb dating yielded two major age clusters: one age cluster at ca. 900 Ma represents the age of the protolith for the felsic granulite, and another age cluster at ca. 500 Ma represents the post-UHT (ultrahigh temperature) stage based on the rare earth element distribution coefficients between zircon and garnet. Meanwhile, in situ monazites U-Pb dating yielded a weighted mean 206Pb/238U age of 482 ± 3.5 Ma, and the monazite U-Pb age was interpreted to be in agreement with the metamorphic zircon rims data, which together with zircon recorded the cooling time after the UHT stage. Whole-rock major and trace elements as well as Sr-Nd isotopes suggest that the protolith of the felsic granulite derived from partial melting of ancient crustal materials with the addition of mantle materials. Integrating these results along with previous studies, we propose that the felsic granulites metamorphosed from the Neoproterozoic granitic rocks, and the granitic rocks with associated mafic-ultramafic rocks suffered a common high-pressure–ultrahigh temperature (HP-UHT) metamorphism and subsequent granulite-facies metamorphism. A tentative model of subduction-relamination was proposed for the geodynamic evolution of the Bashiwake unit, South Altyn Tagh.

Multiple-stage hydrothermal alteration in porphyry copper systems in northern Turkey: the temporal interplay of potassic, propylitic, and phyllic fluids

1980 ◽  
Vol 17 (7) ◽  
pp. 901-926 ◽  
Author(s):  
R. P. Taylor ◽  
B. J. Fryer
Keyword(s):  
Rare Earth ◽  
Hydrothermal Alteration ◽  
Rare Earth Element ◽  
Earth Element ◽  
Root Zone ◽  
Porphyry Copper ◽  
Hydrothermal Fluids ◽  
New Mineral ◽  
Potassic Alteration ◽  
Different Levels

The Bakircay and Ulutas Cu–Mo prospects represent the first occurrences of porphyry mineralization to be described in Turkey.Differences observed in the two prospects in terms of hydrothermal alteration (in particular, alteration overprinting), igneous textures, abundance of xenoliths, breccia phenomena, and style and intensity of fracturing may relate to different levels of exposure within a model porphyry system, Bakircay representing the deep root zone of such a system and Ulutas reflecting much higher levels close to the apex of such a system, or may simply reflect different levels of emplacement.The alteration assemblages present at the Bakircay prospect lend themselves to a geochemical study of the temporal variations in the hydrothermal fluids responsible for single- and multiple-stage alteration–mineralization. The chemical changes involved during single-stage potassic alteration are related to amphibole breakdown and the deposition of hydrothermal biotite (and chalcopyrite). These changes are manifested in light rare-earth element (LREE) enrichment and heavy rare-earth element (HREE) depletion reflecting the high K+ and Cl− activity of the hydrothermal fluids. During propylitic overprinting of potassic alteration changes in whole-rock geochemistry relate to the destruction of biotite (both igneous and hydrothermal) and the formation of chlorite, epidote, calcite, and apatite. These changes result in the loss of ail rare-earth elements (REE) due to increasing fluid/rock ratios and further changes within the HREE relating to zircon stability and the deposition of new mineral phases, e.g., epidote. Conversion of preexisting alteration types lo the quartz–sericite–pyrite ± rutile, calcite assemblages, typical of phyllic alteration, results in the loss of all elements not accommodated in these phases. The high fluid/rock ratios and low pH of the fluids cause progressive leaching of all REE, particularly the lightest (La and Ce).

Rare earth element mobility associated with uranium mineralisation

Nature ◽  
1979 ◽  
Vol 282 (5736) ◽  
pp. 247-250 ◽  
Author(s):  
Scott M. McLennan ◽  
S. R. Taylor
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Earth Element ◽  
Element Mobility ◽  
Uranium Mineralisation
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