Rb-Sr isotopic composition of granites in the Western Krun, hory/Erzgebirge pluton, Central Europe: record of variations in source lithologies, mafic magma input and postmagmatic hydrothermal events

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F16%3A10328922" target="_blank" >RIV/00216208:11310/16:10328922 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1007/s00710-016-0434-6" target="_blank" >http://dx.doi.org/10.1007/s00710-016-0434-6</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00710-016-0434-6" target="_blank" >10.1007/s00710-016-0434-6</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Rb-Sr isotopic composition of granites in the Western Krun, hory/Erzgebirge pluton, Central Europe: record of variations in source lithologies, mafic magma input and postmagmatic hydrothermal events

Popis výsledku v původním jazyce

The late Variscan (327-318 Ma) Western Krun, hory/Erzgebirge pluton (Czech Republic and Germany) represents a multiply emplaced intrusive sequence ranging from low-F biotite monzogranites (with rare minor bodies of gabbrodiorites and granodiorites) to high-F topaz-zinnwaldite alkali-feldspar granites. This granite suite is characterized by progressively increasing concentrations of incompatible elements (Li, Rb, F), monotonous decrease in mafic components and compatible elements (FeOtot, MgO, TiO2, CaO, Sr) with increasing silica. Consequently, this leads to extreme variations in the Rb/Sr ratios (0.52 to 59), which impose highly variable Rb-87/Sr-86 and Sr-87/Sr-86 signatures. The low-F biotite monzogranites represent isotopically heterogeneous mixture with (Sr-87/Sr-86)(323) = 0.707-0.709 between partial melts from the Saxothuringian metasediments and mantle-derived mafic precursors. The medium-F two-mica microgranites show variable (Sr-87/Sr-86)(323) = 0.708-0.714, indicating involvement of multiple precursors and more mature crustal protoliths. The evolved high-F topaz-zinnwaldite alkali-feldspar granites were derived from a precursor with (Sr-87/Sr-86)(320) = 0.707-0.708 at 324-317 Ma by differentiation, which produced the extreme Rb/Sr enrichment and variations. The Li/Rb ratios remain nearly constant (similar to 0.5), thus insensitive to the degree of geochemical differentiation. In comparison to terrestrial variations, the high Li/Rb values indicate derivation of granitic magmas from predominantly sedimentary precursors, in accord with Li-7-Li-6 and Nd-143-Nd-144 isotope composition reported previously. The Rb-Sr element variations in each granite unit are sligthly different and indicate ascent and emplacement of separate magma batches, which do not form a single liquid line of descent.

Název v anglickém jazyce

Rb-Sr isotopic composition of granites in the Western Krun, hory/Erzgebirge pluton, Central Europe: record of variations in source lithologies, mafic magma input and postmagmatic hydrothermal events

Popis výsledku anglicky

The late Variscan (327-318 Ma) Western Krun, hory/Erzgebirge pluton (Czech Republic and Germany) represents a multiply emplaced intrusive sequence ranging from low-F biotite monzogranites (with rare minor bodies of gabbrodiorites and granodiorites) to high-F topaz-zinnwaldite alkali-feldspar granites. This granite suite is characterized by progressively increasing concentrations of incompatible elements (Li, Rb, F), monotonous decrease in mafic components and compatible elements (FeOtot, MgO, TiO2, CaO, Sr) with increasing silica. Consequently, this leads to extreme variations in the Rb/Sr ratios (0.52 to 59), which impose highly variable Rb-87/Sr-86 and Sr-87/Sr-86 signatures. The low-F biotite monzogranites represent isotopically heterogeneous mixture with (Sr-87/Sr-86)(323) = 0.707-0.709 between partial melts from the Saxothuringian metasediments and mantle-derived mafic precursors. The medium-F two-mica microgranites show variable (Sr-87/Sr-86)(323) = 0.708-0.714, indicating involvement of multiple precursors and more mature crustal protoliths. The evolved high-F topaz-zinnwaldite alkali-feldspar granites were derived from a precursor with (Sr-87/Sr-86)(320) = 0.707-0.708 at 324-317 Ma by differentiation, which produced the extreme Rb/Sr enrichment and variations. The Li/Rb ratios remain nearly constant (similar to 0.5), thus insensitive to the degree of geochemical differentiation. In comparison to terrestrial variations, the high Li/Rb values indicate derivation of granitic magmas from predominantly sedimentary precursors, in accord with Li-7-Li-6 and Nd-143-Nd-144 isotope composition reported previously. The Rb-Sr element variations in each granite unit are sligthly different and indicate ascent and emplacement of separate magma batches, which do not form a single liquid line of descent.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

DB - Geologie a mineralogie

OECD FORD obor

—

Projekt

<a href="/cs/project/GAP210%2F12%2F0986" target="_blank" >GAP210/12/0986: Termodynamika a kinetika látkového přenosu, krystalizace a vývoje textur v magmatických a hydrotermálních systémech</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název periodika

Mineralogy and Petrology

ISSN

0930-0708

e-ISSN

—

Svazek periodika

110

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

AT - Rakouská republika

Počet stran výsledku

22

Strana od-do

601-622

Kód UT WoS článku

000385254200003

EID výsledku v databázi Scopus

2-s2.0-84960092338