Spojeni mezi plastovou metasomatosou a isotopy lithia: doklad ze sklonosnych a skryte metasomatisovanych xenolitu z Mongolska

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F08%3A00000199" target="_blank" >RIV/00025798:_____/08:00000199 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Links between mantle metasomatism and lithium isotopes: Evidence from glass-bearing and cryptically metasomatized xenoliths from Mongolia

Popis výsledku v původním jazyce

Li and ?7Li data are presented for Mongolian peridotite xenoliths. These range from fertile lherzolites, with LREE-depleted patterns and little or no metasomatism, to refractory harzburgites characterized by strong LREE-enrichments, negative HFSE anomalies and high Zr/Hf; the latter rocks were likely metasomatized by carbonate-rich melts. The majority of the peridotites show differences in Li (1-1.7 ppm) and ?7Li (+3.8 to +5.7 per thousand), but these variations are not related to any indices of metasomatism. Two xenoliths with abundant melt pockets are enriched in Li (~ 4 ppm) as a result of a metasomatic event that promoted incipient melting; those pockets have lower ?7Li than coexisting olivines. We explain this as an effect of late-stage diffusivefractionation with preferential 6Li re-distribution into the newly formed melt. Another Mongolian xenolith shows a larger ?7Li difference between cpx and melt pocket, in accord with studies of Li isotope fractionation between mantle phase

Název v anglickém jazyce

Links between mantle metasomatism and lithium isotopes: Evidence from glass-bearing and cryptically metasomatized xenoliths from Mongolia

Popis výsledku anglicky

Li and ?7Li data are presented for Mongolian peridotite xenoliths. These range from fertile lherzolites, with LREE-depleted patterns and little or no metasomatism, to refractory harzburgites characterized by strong LREE-enrichments, negative HFSE anomalies and high Zr/Hf; the latter rocks were likely metasomatized by carbonate-rich melts. The majority of the peridotites show differences in Li (1-1.7 ppm) and ?7Li (+3.8 to +5.7 per thousand), but these variations are not related to any indices of metasomatism. Two xenoliths with abundant melt pockets are enriched in Li (~ 4 ppm) as a result of a metasomatic event that promoted incipient melting; those pockets have lower ?7Li than coexisting olivines. We explain this as an effect of late-stage diffusivefractionation with preferential 6Li re-distribution into the newly formed melt. Another Mongolian xenolith shows a larger ?7Li difference between cpx and melt pocket, in accord with studies of Li isotope fractionation between mantle phase

Druh

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

CEP obor

DD - Geochemie

OECD FORD obor

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Projekt

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Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2008

Kód důvěrnosti údajů

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

Název periodika

Earth and Planetary Science Letters

ISSN

0012-821X

e-ISSN

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Svazek periodika

276

Číslo periodika v rámci svazku

1-2

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

9

Strana od-do

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Kód UT WoS článku

261679200021

EID výsledku v databázi Scopus

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