Monazite geochronology in melt-percolated UHP meta-granitoids: an example from the Erzgebirge continental subduction wedge, Bohemian Massif

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F21%3A00000016" target="_blank" >RIV/00025798:_____/21:00000016 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985530:_____/21:00539597 RIV/00216208:11310/21:10416437

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0009254120304587" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0009254120304587</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.chemgeo.2020.119919" target="_blank" >10.1016/j.chemgeo.2020.119919</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Monazite geochronology in melt-percolated UHP meta-granitoids: an example from the Erzgebirge continental subduction wedge, Bohemian Massif

Popis výsledku v původním jazyce

Coupled age and trace element mapping in monazite grains using the Laser-Ablation Split-Stream ICP-MS technique was carried out for a sequence of samples from (U)HP crustal section in the Eger Crystalline Complex interpreted as a Variscan continental subduction wedge. The sampled section comprises banded orthogneiss with monazite protolith ages of ~485 Ma. The orthogneiss was heterogeneously transformed to migmatite, HP felsic granofels and U(HP) fine-grained Ky-Kfs granulite during coupled deformation and percolation of silicate melts in a subduction channel. Age of the (U)HP metamorphism and related melt percolation in the granulite is dated by Th-rich and HREE-poor monazite cores at 353.6±2.7[7] Ma, that are in equilibrium with HREE-rich garnets. Th-rich cores of monazites in the migmatite, granofels and granulite that lack the (U)HP signatures show younger ages of 347.8±3.4[7] Ma, 345.8±2.4[7] Ma and 339.3±1.3 Ma, respectively. The monazite rims with lower Th and higher HREE contents than the monazite cores are likely a result of (re)crystallization in equilibrium with melt that partly dissolved the HREE-rich prograde garnet during decompression. This (re)crystallization is constrained by ages of 344.2±1.6[7] Ma in (U)HP granulites and 338-340±[8] Ma in migmatites, granofelses and granulites without the (U)HP signature. The groups of ages from 353 Ma to 338 Ma, are significantly different when only their in-run uncertainties (7-10 Ma) are compared and indicate a 15±3 Myr period of monazite (re)crystallization from burial/peak to exhumation.

Název v anglickém jazyce

Monazite geochronology in melt-percolated UHP meta-granitoids: an example from the Erzgebirge continental subduction wedge, Bohemian Massif

Popis výsledku anglicky

Coupled age and trace element mapping in monazite grains using the Laser-Ablation Split-Stream ICP-MS technique was carried out for a sequence of samples from (U)HP crustal section in the Eger Crystalline Complex interpreted as a Variscan continental subduction wedge. The sampled section comprises banded orthogneiss with monazite protolith ages of ~485 Ma. The orthogneiss was heterogeneously transformed to migmatite, HP felsic granofels and U(HP) fine-grained Ky-Kfs granulite during coupled deformation and percolation of silicate melts in a subduction channel. Age of the (U)HP metamorphism and related melt percolation in the granulite is dated by Th-rich and HREE-poor monazite cores at 353.6±2.7[7] Ma, that are in equilibrium with HREE-rich garnets. Th-rich cores of monazites in the migmatite, granofels and granulite that lack the (U)HP signatures show younger ages of 347.8±3.4[7] Ma, 345.8±2.4[7] Ma and 339.3±1.3 Ma, respectively. The monazite rims with lower Th and higher HREE contents than the monazite cores are likely a result of (re)crystallization in equilibrium with melt that partly dissolved the HREE-rich prograde garnet during decompression. This (re)crystallization is constrained by ages of 344.2±1.6[7] Ma in (U)HP granulites and 338-340±[8] Ma in migmatites, granofelses and granulites without the (U)HP signature. The groups of ages from 353 Ma to 338 Ma, are significantly different when only their in-run uncertainties (7-10 Ma) are compared and indicate a 15±3 Myr period of monazite (re)crystallization from burial/peak to exhumation.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GA19-25035S" target="_blank" >GA19-25035S: Granulito–migmatitové dómy - náhled do devonského a karbonského vývoje Variského orogenního pásma</a><br>

Návaznosti

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

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Chemical Geology

ISSN

0009-2541

e-ISSN

—

Svazek periodika

559

Číslo periodika v rámci svazku

January : 119919

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

19

Strana od-do

nestránkováno

Kód UT WoS článku

000600546500031

EID výsledku v databázi Scopus

2-s2.0-85093652645