Structural, metamorphic and geochronological constraints on Palaeozoic multi-stage geodynamic evolution of the Altai accretionary wedge system (Hovd Zone, western Mongolia)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F21%3A00000134" target="_blank" >RIV/00025798:_____/21:00000134 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985831:_____/21:00542296 RIV/00216208:11310/21:10429340

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0024493721002401?via%3Dihub#ks0005" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0024493721002401?via%3Dihub#ks0005</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.lithos.2021.106204" target="_blank" >10.1016/j.lithos.2021.106204</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Structural, metamorphic and geochronological constraints on Palaeozoic multi-stage geodynamic evolution of the Altai accretionary wedge system (Hovd Zone, western Mongolia)

Popis výsledku v původním jazyce

A polyphase tectono-metamorphic evolution of the Mongolian tract of the Central Asian Orogenic Belt (CAOB) is inferred from a structural, petrological and geochronological study in the Hovd Zone at the NE periphery of the Altai Domain. Four tectonic events are recorded here. A relict sub-vertical fabric (S1) is associated with the growth of garnet cores and staurolite, typical of MP–MT Barrovian-type metamorphism (M1). This fabric was isoclinally folded and overprinted by sub-horizontal foliation (S2) associated with growth of garnet rims, sillimanite and cordierite, typical of LP–HT metamorphism (M2). The P–T path inferred from petrology and thermodynamic modelling shows that the peak conditions reached 590–610 °C and c. 5.8 kbar (M1) and were followed by decompression to 4–5 kbar associated with heating to 630–690 °C (M2). Subsequently, the studied region was strongly reworked by NW–SE trending upright folds (F3) locally associated with development of muscovite- and chlorite-bearing cleavage (S3). The region is weakly affected by post-metamorphic D4 overprint. Monazite in-situ electron-microprobe dating was complemented by LA–ICP-MS U–Pb dating, revealing three distinct texturally defined age groups at c. 455, 435 and 385 Ma. The ages at c. 455 Ma are related with monazite included in garnet cores, the age group at c. 435 Ma with monazite in garnet rims and in S2 foliation, while the ages of c. 385 Ma come mostly from monazite in chlorite–muscovite-bearing bands. Based on the monazite textural position and REE patterns, these ages are correlated with the tectono-metamorphic events D1–D3, reflecting short-lived Late Ordovician shortening, prolonged Middle Silurian–Early Devonian extension and Late Devonian–Early Carboniferous compression, respectively. Alternation of shortening and extension periods is interpreted as being caused by tectonic switching, i.e. repeated alternation of advancing and retreating subduction regimes. The latest Permian event resulted from the collision of the Mongolian orogenic collage with the Tarim and North China cratons in the south and caused rotation of previous fabrics to the current configuration.

Název v anglickém jazyce

Structural, metamorphic and geochronological constraints on Palaeozoic multi-stage geodynamic evolution of the Altai accretionary wedge system (Hovd Zone, western Mongolia)

Popis výsledku anglicky

A polyphase tectono-metamorphic evolution of the Mongolian tract of the Central Asian Orogenic Belt (CAOB) is inferred from a structural, petrological and geochronological study in the Hovd Zone at the NE periphery of the Altai Domain. Four tectonic events are recorded here. A relict sub-vertical fabric (S1) is associated with the growth of garnet cores and staurolite, typical of MP–MT Barrovian-type metamorphism (M1). This fabric was isoclinally folded and overprinted by sub-horizontal foliation (S2) associated with growth of garnet rims, sillimanite and cordierite, typical of LP–HT metamorphism (M2). The P–T path inferred from petrology and thermodynamic modelling shows that the peak conditions reached 590–610 °C and c. 5.8 kbar (M1) and were followed by decompression to 4–5 kbar associated with heating to 630–690 °C (M2). Subsequently, the studied region was strongly reworked by NW–SE trending upright folds (F3) locally associated with development of muscovite- and chlorite-bearing cleavage (S3). The region is weakly affected by post-metamorphic D4 overprint. Monazite in-situ electron-microprobe dating was complemented by LA–ICP-MS U–Pb dating, revealing three distinct texturally defined age groups at c. 455, 435 and 385 Ma. The ages at c. 455 Ma are related with monazite included in garnet cores, the age group at c. 435 Ma with monazite in garnet rims and in S2 foliation, while the ages of c. 385 Ma come mostly from monazite in chlorite–muscovite-bearing bands. Based on the monazite textural position and REE patterns, these ages are correlated with the tectono-metamorphic events D1–D3, reflecting short-lived Late Ordovician shortening, prolonged Middle Silurian–Early Devonian extension and Late Devonian–Early Carboniferous compression, respectively. Alternation of shortening and extension periods is interpreted as being caused by tectonic switching, i.e. repeated alternation of advancing and retreating subduction regimes. The latest Permian event resulted from the collision of the Mongolian orogenic collage with the Tarim and North China cratons in the south and caused rotation of previous fabrics to the current configuration.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GX19-27682X" target="_blank" >GX19-27682X: Hlavní mechanismy periferálního kontinentálního růstu během superkontinentálního cyklu</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

Lithos

ISSN

0024-4937

e-ISSN

—

Svazek periodika

396-397

Číslo periodika v rámci svazku

September : 106204

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

20

Strana od-do

nestránkováno

Kód UT WoS článku

000670300500004

EID výsledku v databázi Scopus

2-s2.0-85105572384