Mineralogy and element geochemistry of the Bayan Obo (China) carbonatite dykes: Implications for REE mineralization

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F41601670%3A_____%2F24%3AN0000001" target="_blank" >RIV/41601670:_____/24:N0000001 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.oregeorev.2024.105873" target="_blank" >https://doi.org/10.1016/j.oregeorev.2024.105873</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.oregeorev.2024.105873" target="_blank" >10.1016/j.oregeorev.2024.105873</a>

Result language

angličtina

Original language name

Mineralogy and element geochemistry of the Bayan Obo (China) carbonatite dykes: Implications for REE mineralization

Original language description

The Bayan Obo deposit in China is the world’s largest rare earth element (REE) deposit. However, its genesis remains highly debated. It is considered to have a close genetic association with carbonatites because of the presence of nearby carbonatite dykes and the geochemical similarities between these dykes and the orebody. However, the evolution of these dykes and associated REE mineralization remain poorly understood, hindering the origin interpretation of the deposit. This study provides new insights into the petrography, mineralogy, and major- and trace-element geochemistry of these carbonatite dykes and rock-forming minerals to reconstruct the magmatic evolution and REE enrichment of the deposit. The dykes evolved from dolomite- to calcite-dominated (i.e., calcite and fenitized calcite) carbonatites, and their REE content remarkably increased, with the latter developing strong REE mineralization. The dolomites and minor calcites within the dolomite carbonatites exhibit a steep negative slope with high light REE (LREE) enrichment and heavy REE (HREE) depletion, similar to the whole rock. In contrast, the calcites from the calcite-dominated carbonatites exhibit flat REE patterns with HREE enrichment. Combined with previous isotopic data and our petrology, mineralogy, and geochemistry study, we propose that these rocks are derived directly from the low-degree melting of the underlying mantle source. REE mineralization may be related to the progressive crystallization of rock-forming calcites of calcite-dominated carbonatites. Monazite, bastn¨ asite, parisite, and huanghoite are the dominant REE minerals and exhibit intimate associations with barite and alkaline silicate minerals such as aegirine, biotite, K-feldspar, and albite. This assemblage indicates that the REE were primarily transported via REE–sulfate and REE–alkali complexes, with the latter favoring HREE, and the precipitation of alkaline silicate minerals destabilized these REE complexes, facilitating REE mineralization.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10504 - Mineralogy

Project

<a href="/en/project/GX19-29124X" target="_blank" >GX19-29124X: EVOLUTION AND POST-EMPLACEMENT HISTORY OF CARBONATITES: IMPLICATIONS FOR THE MOBILITY AND CONCENTRATION OF CRITICAL METALS</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Ore Geology Reviews

ISSN

0169-1368

e-ISSN

1872-7360

Volume of the periodical

165

Issue of the periodical within the volume

January 18, 2024

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

15

Pages from-to

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UT code for WoS article

001170842400001

EID of the result in the Scopus database

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