Publication detail

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

Meng Feng Wenlei Song Jindrich Kynicky Martin Smith Clinten Cox Michaela Kotlanova Martin Brtnicky Wei Fu Chunwan Wei

Original Title

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

Type

journal article in Web of Science

Language

English

Original Abstract

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 degrees C 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.

Keywords

Carbonatite; Melt inclusion; REE; Phosphate; Immiscibility; Mineralization; Ulgii Khiid

Authors

Meng Feng; Wenlei Song; Jindrich Kynicky; Martin Smith; Clinten Cox; Michaela Kotlanova; Martin Brtnicky; Wei Fu; Chunwan Wei

Released

26. 2. 2020

Publisher

ELSEVIER

Location

AMSTERDAM

ISBN

0169-1368

Periodical

ORE GEOLOGY REVIEWS

Year of study

117

Number

103294

State

Kingdom of the Netherlands

Pages from

1

Pages to

14

Pages count

14

URL

https://www.sciencedirect.com/science/article/pii/S0169136818304359

BibTex

@article{BUT165722,
  author="Meng Feng and Wenlei Song and Jindrich Kynicky and Martin Smith and Clinten Cox and Michaela Kotlanova and Martin Brtnicky and Wei Fu and Chunwan Wei",
  title="Primary rare earth element enrichment in carbonatites: Evidence from melt inclusions in Ulgii Khiid carbonatite, Mongolia",
  journal="ORE GEOLOGY REVIEWS",
  year="2020",
  volume="117",
  number="103294",
  pages="1--14",
  doi="10.1016/j.oregeorev.2019.103294",
  issn="0169-1368",
  url="https://www.sciencedirect.com/science/article/pii/S0169136818304359"
}