Primary rare earth element enrichment in carbonatites: Evidence from melt inclusions in Ulgii Khiid carbonatite, Mongolia

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62156489%3A43210%2F20%3A43917430" target="_blank" >RIV/62156489:43210/20:43917430 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/62156489:43410/20:43917430 RIV/00216305:26310/20:PU137574 RIV/41601670:_____/20:N0000037

Výsledek na webu

<a href="https://doi.org/10.1016/j.oregeorev.2019.103294" target="_blank" >https://doi.org/10.1016/j.oregeorev.2019.103294</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.oregeorev.2019.103294" target="_blank" >10.1016/j.oregeorev.2019.103294</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Primary rare earth element enrichment in carbonatites: Evidence from melt inclusions in Ulgii Khiid carbonatite, Mongolia

Popis výsledku v původním jazyce

Carbonatites are abundant in the rare earth elements (REE), and they host the most important REE resources in the world. However, the mechanisms that concentrate these elements during carbonatitic magmatic processes are still poorly constrained. Here, we report the occurrence of apatite-hosted melt inclusions from the Ulgii Khiid carbonatites, Mongolia, and use these to reconstruct the evolution of REE concentrations and patterns in early, primary carbonatite magma. The melt inclusions consist of a varied polycrystalline assemblage of daughter minerals, including calcite, diopside, phlogopite, magnetite, pyrite, monazite, parisite, and a phosphate glass which is remarkably enriched in REE. Heating-quenching experiments show that the homogenization temperatures of the inclusions are above 1200 oC and produce three immiscible liquid phases (i.e., phosphate-, silicate-, and Fe-silicate-melt). The phosphate melt has much higher REE content than the silicate melts. We, therefore, suggest that the melt inclusions trapped a REE-, P- and silicate-enriched carbonate melt produced via carbonate-silicate liquid immiscibility. During this process, both REE and P preferentially incorporated into the carbonate melt. With subsequent crystal fractionation of REE- and P-poor carbonate and silicate minerals, the separated carbonatitic melt becomes P-REE-saturated, forming REE minerals and an immiscible REE-rich phosphate melt. The phosphate melt is highly efficient at concentrating REE during the immiscibility process and plays a crucial role in controlling the REE budget in the P-rich carbonatite magmas.

Název v anglickém jazyce

Primary rare earth element enrichment in carbonatites: Evidence from melt inclusions in Ulgii Khiid carbonatite, Mongolia

Popis výsledku anglicky

Carbonatites are abundant in the rare earth elements (REE), and they host the most important REE resources in the world. However, the mechanisms that concentrate these elements during carbonatitic magmatic processes are still poorly constrained. Here, we report the occurrence of apatite-hosted melt inclusions from the Ulgii Khiid carbonatites, Mongolia, and use these to reconstruct the evolution of REE concentrations and patterns in early, primary carbonatite magma. The melt inclusions consist of a varied polycrystalline assemblage of daughter minerals, including calcite, diopside, phlogopite, magnetite, pyrite, monazite, parisite, and a phosphate glass which is remarkably enriched in REE. Heating-quenching experiments show that the homogenization temperatures of the inclusions are above 1200 oC and produce three immiscible liquid phases (i.e., phosphate-, silicate-, and Fe-silicate-melt). The phosphate melt has much higher REE content than the silicate melts. We, therefore, suggest that the melt inclusions trapped a REE-, P- and silicate-enriched carbonate melt produced via carbonate-silicate liquid immiscibility. During this process, both REE and P preferentially incorporated into the carbonate melt. With subsequent crystal fractionation of REE- and P-poor carbonate and silicate minerals, the separated carbonatitic melt becomes P-REE-saturated, forming REE minerals and an immiscible REE-rich phosphate melt. The phosphate melt is highly efficient at concentrating REE during the immiscibility process and plays a crucial role in controlling the REE budget in the P-rich carbonatite magmas.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

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

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Ore Geology Reviews

ISSN

0169-1368

e-ISSN

—

Svazek periodika

117

Číslo periodika v rámci svazku

February

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

14

Strana od-do

103294

Kód UT WoS článku

000515206900048

EID výsledku v databázi Scopus

2-s2.0-85077496309