Allanite Geochemical Response to Hydrothermal Alteration by Alkaline, Low-Temperature Fluids

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F20%3A00524134" target="_blank" >RIV/67985831:_____/20:00524134 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/2075-163X/10/5/392" target="_blank" >https://www.mdpi.com/2075-163X/10/5/392</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/min10050392" target="_blank" >10.3390/min10050392</a>

Result language

angličtina

Original language name

Allanite Geochemical Response to Hydrothermal Alteration by Alkaline, Low-Temperature Fluids

Original language description

Allanite is one of the main rare earth elements (REE)-rich accessory minerals in composite dykes from the granitoid pluton of Karkonosze. These dykes di er in composition from the bulk of the pluton by elevated rare earth elements (REE), Y, Zr, and alkali contents, suggesting contribution of an additional component. Allanite exhibits complex alteration textures, which can be divided into two stages. The first stage is represented by allanite mantles, formed by fluid infiltration into previously crystallized magmatic allanite. These zones have low totals, are Ca-, Al-, Mg-, and light REE (LREE)-depleted, and Y-, heavy REE (HREE)-, Th-, Ti-, and alkali-enriched. The fractionation between LREE and HREE was caused by di erent mobility of complexes formed by these elements in aqueous fluids. The second stage includes recrystallized LREE-poor, Y-HREE-rich allanite with variable Ca, Al, Mg, and REE-fluorocarbonates. The alteration products from both stages demonstrate higher Fe3+/(Fe2+ + Fe3+) ratios and a negative Ce anomaly. These features point to the alkaline, low-temperature, and oxidized nAture of the fluids. The di erences in mobility and solubility of respective ligands show that the fluids from the first stage may have been dominated by Cl, whereas those of the second stage may have been dominated by F and CO2 (and PO4 in case of one sample). The inferred chemistry of the fluids resembles the overall geochemical signature of the composite dykes, indicating a major contribution of the hydrothermal processes to their geochemical evolution.

Czech name

—

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

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

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

Name of the periodical

Minerals

ISSN

2075-163X

e-ISSN

—

Volume of the periodical

10

Issue of the periodical within the volume

5

Country of publishing house

CH - SWITZERLAND

Number of pages

30

Pages from-to

392

UT code for WoS article

000548343700007

EID of the result in the Scopus database

2-s2.0-85084226926