Geochemical constraints on the origin of phonolites from the Lužické hory Mts., Ohře (Eger) Rift, Bohemian Massif
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F25%3A00642204" target="_blank" >RIV/67985831:_____/25:00642204 - isvavai.cz</a>
Alternative codes found
RIV/61389005:_____/25:00642204 RIV/00216224:14310/25:00143450 RIV/00216208:11310/25:10511044
Result on the web
<a href="https://geologicacarpathica.com/browse/archive/?journal_article_no=41176" target="_blank" >https://geologicacarpathica.com/browse/archive/?journal_article_no=41176</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.31577/GeolCarp.2025.20" target="_blank" >10.31577/GeolCarp.2025.20</a>
Alternative languages
Result language
angličtina
Original language name
Geochemical constraints on the origin of phonolites from the Lužické hory Mts., Ohře (Eger) Rift, Bohemian Massif
Original language description
Geochemical and petrological data are reported for phonolites from the Lužické hory Mts. in the northeastern part of the Ohře (Eger) Rift near the junction with the Lusatian Fault. The rocks are collectively enriched in incompatible trace elements such as Rb, REEs, Zr, Hf, U, Th, Nb, Ta (concentrated mainly in hainite, Nb-rich titanite and aegirine) and volatile components such as F and Cl. On the other hand, the phonolites are significantly depleted in Ti and P and partly also in Sr and Ba contents. The K–Ar dating provided scattered ages in the range from 34 to 27 Ma. Two geochemically different phonolite types were recognized: (i) type A (higher Sr>90 ppm, Ba>130 ppm) having initial 87Sr/86Sr = 0.7032–0.7094 and εNd=2.9–3.4, similar to those phonolites that are predominant in the nearby České středohoří Mts., and (ii) prevailing type B with lower contents of Sr<20 ppm and Ba<60 characterized by a decoupled Sr–Nd systematics (initial 87Sr/86Sr ratios up to ~0.714) at narrow εNd of 3.2–3.8. Yet, both phonolite types exhibit relatively restricted variations in initial 206Pb/204Pb (19.2–19.5), 207Pb/204Pb (15.61–15.66) and 208Pb/204Pb (39.07–39.30), indicating their derivation from a similar metasomatically enriched mantle source. The observed geochemical characteristics of the studied phonolites can be best explained by (i) variable degree of clinopyroxene and feldspar fractional crystallization from primary basanitic magma, (ii) degree of assimilation-fractional crystallization (AFC) processes during the magma ascent, and/or (iii) late-magmatic to post-magmatic hydrothermal processes related to selective enrichment of some incompatible elements.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - 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
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Geologica Carpathica
ISSN
1335-0552
e-ISSN
1336-8052
Volume of the periodical
76
Issue of the periodical within the volume
5
Country of publishing house
SK - SLOVAKIA
Number of pages
20
Pages from-to
369-388
UT code for WoS article
001629632500004
EID of the result in the Scopus database
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