The Origin of Synchysite-(Ce) and Sources of Rare Earth Elements in the Rozna Uranium Deposit, Czech Republic

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F22%3A10452522" target="_blank" >RIV/00216208:11310/22:10452522 - isvavai.cz</a>

Alternative codes found

RIV/00216224:14310/22:00126295

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=L3yYb1Q9p8" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=L3yYb1Q9p8</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/min12060690" target="_blank" >10.3390/min12060690</a>

Result language

angličtina

Original language name

The Origin of Synchysite-(Ce) and Sources of Rare Earth Elements in the Rozna Uranium Deposit, Czech Republic

Original language description

Synchysite was identified in the Rozna uranium deposit in a quartz-carbonate-sulfide vein, which is a part of the late (post-uranium and, post-Variscan) stage of the development of the hydrothermal system. The synchysite forms needles or lamellae, which are almost exclusively bound to the quartz filling of the veins. The structure of the quartz vein-filling, i.e., the preserved tubular syneresis crack pattern, Liesegang bands formed by hematite, chaotic grain size distribution of quartz grains, and ribbons of fibrous SiO2 grains, indicate that the synchysite crystallized in a silica gel. Its formation may be explained by the reaction of hydrothermal acid fluids rich in Fe2+ and rare earth elements (REEs) with alkaline Ca2+ HCO3- and F-rich fluids expelled from the gel during syneresis, or by its ageing. The subsequent recrystallization of the gel to form euhedral quartz grains was accompanied by the deformation of previously formed Liesegang rings, and the development of quartz rosettes. The study of fluid inclusions indicated that the silica gel originated at a very low temperature. The temperatures of the homogenization of two-phase inclusions in carbonate and quartz vein-filling varied between 38 and 74 degrees C, and the salinity ranged between 4 and 10 wt.% NaCl equiv. The delta C-13 carbonate values (from -4.65 to -5.21 parts per thousand, PDB) indicate the deep-seated source of CO2, and delta O-18 values (from 14.76 to 18.22 parts per thousand, SMOW) show that the source of the hydrothermal fluids was mainly surface water, with a possible admixture of fossil saline brines. The main sources of REEs are thought to have predominantly been uranium minerals (coffinitized uraninite and coffinite) that form a part of the breccia fragments embedded in the vein filling. The results illustrate the significant mobility of REEs in the late, low-temperature hydrothermal system, and they indicate the multiple remobilizations of REEs in the uranium deposits in general.

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

10505 - Geology

Project

<a href="/en/project/EF16_026%2F0008459" target="_blank" >EF16_026/0008459: Long-term research of geochemical barriers for nuclear waste disposal</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

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

12

Issue of the periodical within the volume

6

Country of publishing house

CH - SWITZERLAND

Number of pages

26

Pages from-to

690

UT code for WoS article

000817325700001

EID of the result in the Scopus database

2-s2.0-85130914255