REE‐Rich Turonian Phosphates in the Bohemian Cretaceous Basin, Czech Republic: Assessment as Source of Critical Elements and Implications for Future Exploration

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F21%3A00000099" target="_blank" >RIV/00025798:_____/21:00000099 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/journal/minerals" target="_blank" >https://www.mdpi.com/journal/minerals</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/min11030246" target="_blank" >10.3390/min11030246</a>

Result language

angličtina

Original language name

REE‐Rich Turonian Phosphates in the Bohemian Cretaceous Basin, Czech Republic: Assessment as Source of Critical Elements and Implications for Future Exploration

Original language description

Numerous phosphate occurrences are located in the Bohemian Cretaceous Basin (BCB) of the Czech Republic, within the Cenomanian–Turonian sequences. Small phosphate occurrences have been reported in the Upper Cenomanian, Lower Turonian, and Upper Turonian marine glauconitic siliciclasts. The phosphates are generally <;1 m thick, present as phosphatized hardgrounds,nodules, coprolites, skeletal remains, phosphatized shells, peloids, sponges, and tube‐fills, associated with black mudstone and other siliciclasts. Only recently the critical elements have been highlightedin these phosphates. The present study covers eight of these occurrences and provides information on petrography, mineralogy, and chemical composition of major elements, trace elements, and stable isotopes. The phosphate mineralogy is comprised of carbonate‐fluorapatite, associatedwith quartz, glauconite, smectite, kaolinite, and pyrite. Most of the phosphates are rich in organic matter. The phosphate chemistry is dominated by P2O5, CaO, F, Na2O, SO3, and CO2. Minor amounts of SiO2, Al2O3, K2O, and MgO are found, related to quartz and alumino‐silicate impurities.Evidence of fossil microbial structures is revealed. The indices derived from rare earth elements(REE) indicate phosphogenesis at various redox conditions, ranging from anoxic to oxic, whereas the carbon stable isotopes of the apatite suggest generally reducing conditions. The critical and othervaluable elements found in these Mid‐Cretaceous phosphates include P2O5 (18.9–26.76 wt. percent), F(1.67–3.25 wt. percent), REE (325–1338 ppm), Y (74–368 ppm), and U (10.4–37.9 ppm). The investigation of the Turonian phosphate occurrences show that those located at the base of the Bílá Hora Formation(earliest Turonian) are the most persistent in the southern margins of the BCB, and found in localities extending for about 200 km. They were developed at the onset of the Early Turonian global transgression and are strata‐bound to the base of the Bílá Hora Formation. Future exploration formarine sedimentary phosphorites should focus on thicker and better developed deposits at the base of the Turonian sediments as the main target.

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

—

Continuities

R - Projekt Ramcoveho programu EK

Publication year

2021

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

11

Issue of the periodical within the volume

3 : 246

Country of publishing house

CH - SWITZERLAND

Number of pages

21

Pages from-to

1-21

UT code for WoS article

000633912000001

EID of the result in the Scopus database

2-s2.0-85101575122