Petrogenesis of Miocene alkaline volcanic suites from western Bohemia. Whole rock geochemistry and Sr-Nd-Pb isotopic signatures.

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F16%3A00459103" target="_blank" >RIV/67985831:_____/16:00459103 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216305:26110/16:PU118961

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.chemer.2015.11.003" target="_blank" >http://dx.doi.org/10.1016/j.chemer.2015.11.003</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.chemer.2015.11.003" target="_blank" >10.1016/j.chemer.2015.11.003</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Petrogenesis of Miocene alkaline volcanic suites from western Bohemia. Whole rock geochemistry and Sr-Nd-Pb isotopic signatures.

Popis výsledku v původním jazyce

The Mid to Late Miocene intraplate alkaline volcanic suites of western Bohemia are relict of the intensive voluminous volcanism accompanied by large-scale uplift and doming. The association with the uplift of the NE flank of the Cheb–Domažlice Graben (CDG) is uncertain in view of the mostly transpressional tectonics of the graben. The volcanism is most probably of the Ohře/Eger Rift off-rift settings. Two cogenetic volcanic suites have been recognised: (i) silica-saturated to oversaturated consisting of olivine basalt – trachybasalt – (basaltic) trachyandesite – trachyte – rhyolite (13.5 to 10.2 Ma) and (ii) silica-undersaturated (significantly Ne-normative) (melilite-bearing) olivine nephelinite – basanite – tephrite (18.3 to 6.25 Ma). A common mantle source is assumed for the near-primary mantle-derived compositions of both suites, i.e., olivine basalt and olivine nephelinite. Apparently, they were generated by different degrees of partial melting of a common mantle source, with garnet, olivine and clinopyroxene in the residuum. Negative Rb and K anomalies indicate a residual K-phase (amphibole/phlogopite) and melting of partly metasomatised mantle lithosphere. The evolution of the olivine basalt – trachybasalt – (basaltic) trachyandesite – trachyte – rhyolite suite suggests the presence of an assimilation–fractional crystallization process (AFC). The magmas were probably sourced by both sub-lithospheric and lithospheric partly metasomatised mantle. The evolution of the (melilite-bearing) olivine nephelinite – basanite – tephrite suite is less clear because of its limited extent. The Sr-Nd-Pb isotopic composition of primitive volcanic rocks of both suites is similar to that of the European Asthenospheric Reservoir (EAR). Initial Pb isotopic data plot partly above the northern hemisphere reference line at radiogenic 206Pb/204Pb ratios of 19 to 20, and indicate the presence of a Variscan crustal component in the source.

Název v anglickém jazyce

Petrogenesis of Miocene alkaline volcanic suites from western Bohemia. Whole rock geochemistry and Sr-Nd-Pb isotopic signatures.

Popis výsledku anglicky

The Mid to Late Miocene intraplate alkaline volcanic suites of western Bohemia are relict of the intensive voluminous volcanism accompanied by large-scale uplift and doming. The association with the uplift of the NE flank of the Cheb–Domažlice Graben (CDG) is uncertain in view of the mostly transpressional tectonics of the graben. The volcanism is most probably of the Ohře/Eger Rift off-rift settings. Two cogenetic volcanic suites have been recognised: (i) silica-saturated to oversaturated consisting of olivine basalt – trachybasalt – (basaltic) trachyandesite – trachyte – rhyolite (13.5 to 10.2 Ma) and (ii) silica-undersaturated (significantly Ne-normative) (melilite-bearing) olivine nephelinite – basanite – tephrite (18.3 to 6.25 Ma). A common mantle source is assumed for the near-primary mantle-derived compositions of both suites, i.e., olivine basalt and olivine nephelinite. Apparently, they were generated by different degrees of partial melting of a common mantle source, with garnet, olivine and clinopyroxene in the residuum. Negative Rb and K anomalies indicate a residual K-phase (amphibole/phlogopite) and melting of partly metasomatised mantle lithosphere. The evolution of the olivine basalt – trachybasalt – (basaltic) trachyandesite – trachyte – rhyolite suite suggests the presence of an assimilation–fractional crystallization process (AFC). The magmas were probably sourced by both sub-lithospheric and lithospheric partly metasomatised mantle. The evolution of the (melilite-bearing) olivine nephelinite – basanite – tephrite suite is less clear because of its limited extent. The Sr-Nd-Pb isotopic composition of primitive volcanic rocks of both suites is similar to that of the European Asthenospheric Reservoir (EAR). Initial Pb isotopic data plot partly above the northern hemisphere reference line at radiogenic 206Pb/204Pb ratios of 19 to 20, and indicate the presence of a Variscan crustal component in the source.

Druh

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

CEP obor

DD - Geochemie

OECD FORD obor

—

Projekt

<a href="/cs/project/LO1408" target="_blank" >LO1408: AdMaS UP - Pokročilé stavební materiály, konstrukce a technologie</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

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

Název periodika

Chemie der Erde-Geochemistry

ISSN

0009-2819

e-ISSN

—

Svazek periodika

76

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

17

Strana od-do

77-93

Kód UT WoS článku

000376216500006

EID výsledku v databázi Scopus

2-s2.0-84949034787