Tectonic Juxtaposition of Two Independent Paleoproterozoic Arcs by Cenozoic Duplexing in the Arun Tectonic Window of the Eastern Nepalese Himalaya

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F22%3A00000159" target="_blank" >RIV/00025798:_____/22:00000159 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.frontiersin.org/articles/10.3389/feart.2022.890171/full" target="_blank" >https://www.frontiersin.org/articles/10.3389/feart.2022.890171/full</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3389/feart.2022.890171" target="_blank" >10.3389/feart.2022.890171</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Tectonic Juxtaposition of Two Independent Paleoproterozoic Arcs by Cenozoic Duplexing in the Arun Tectonic Window of the Eastern Nepalese Himalaya

Popis výsledku v původním jazyce

The tectonic evolution of the Himalayan orogenic belt before Cenozoic convergence isimportant to understand its modern structural framework. There is still controversyregarding the tectonic history of the lower Lesser Himalaya Sequence (LHS) in the frameof the Paleoproterozoic geological record. In this study, integrated analysis of field geology,zircon U-Pb age, Hf isotope, and whole-rock geochemistry was conducted across the LHSand the Main Central Thrust zone in the Arun Valley, eastern Nepal, to address theirPrecambrian tectonic evolution and the later convergence. Two groups ofmetasedimentary rocks with different age spectrums of detrital zircons and Hf isotope inthe Paleoproterozoic can be distinguished in an imbricated duplexing system in the study area.One group with a maximum depositional age around ca. 1800Ma has a unimodal detritalzircon pattern and negative zircon ƐHf (t) values ranging from −8.9 to 0.9. These data can beinterpreted to reflect the deposition of zircons close to a Japanese-type arc that was isolatedfrom the northern Indian Craton. The other group of calc-silicate rocks and quartzite withmultiple peaks of detrital zircons in the Paleoproterozoic show a younger maximumdepositional age around ca. 1,600Ma and variable zircon ƐHf (t) values ranging from −6.7to 8.8, indicating their deposition in a back-arc basin of an Andean-type arc established on thenorthern Indian Craton. The geochemistry of an orthogneiss sample dated at 1783 ± 11Maindicates high potassium, peraluminous granodiorite protolith emplaced in a volcanic arc orsyn-collisional tectonic setting, supporting the existence of the Paleoproterozoic Andean-typearc. We hypothesize that possibly two arc systems developed, respectively, onto and in theproximity of northern Indian Craton in the Paleoproterozoic at the final stages of the Columbiasupercontinent formation. These two arcs were juxtaposed either in the Paleoproterozoic orCenozoic time, and were finally imbricated during the Cenozoic duplexing.

Název v anglickém jazyce

Tectonic Juxtaposition of Two Independent Paleoproterozoic Arcs by Cenozoic Duplexing in the Arun Tectonic Window of the Eastern Nepalese Himalaya

Popis výsledku anglicky

The tectonic evolution of the Himalayan orogenic belt before Cenozoic convergence isimportant to understand its modern structural framework. There is still controversyregarding the tectonic history of the lower Lesser Himalaya Sequence (LHS) in the frameof the Paleoproterozoic geological record. In this study, integrated analysis of field geology,zircon U-Pb age, Hf isotope, and whole-rock geochemistry was conducted across the LHSand the Main Central Thrust zone in the Arun Valley, eastern Nepal, to address theirPrecambrian tectonic evolution and the later convergence. Two groups ofmetasedimentary rocks with different age spectrums of detrital zircons and Hf isotope inthe Paleoproterozoic can be distinguished in an imbricated duplexing system in the study area.One group with a maximum depositional age around ca. 1800Ma has a unimodal detritalzircon pattern and negative zircon ƐHf (t) values ranging from −8.9 to 0.9. These data can beinterpreted to reflect the deposition of zircons close to a Japanese-type arc that was isolatedfrom the northern Indian Craton. The other group of calc-silicate rocks and quartzite withmultiple peaks of detrital zircons in the Paleoproterozoic show a younger maximumdepositional age around ca. 1,600Ma and variable zircon ƐHf (t) values ranging from −6.7to 8.8, indicating their deposition in a back-arc basin of an Andean-type arc established on thenorthern Indian Craton. The geochemistry of an orthogneiss sample dated at 1783 ± 11Maindicates high potassium, peraluminous granodiorite protolith emplaced in a volcanic arc orsyn-collisional tectonic setting, supporting the existence of the Paleoproterozoic Andean-typearc. We hypothesize that possibly two arc systems developed, respectively, onto and in theproximity of northern Indian Craton in the Paleoproterozoic at the final stages of the Columbiasupercontinent formation. These two arcs were juxtaposed either in the Paleoproterozoic orCenozoic time, and were finally imbricated during the Cenozoic duplexing.

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

2022

Kód důvěrnosti údajů

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

Název periodika

Frontiers in Earth Science

ISSN

2296-6463

e-ISSN

—

Svazek periodika

10

Číslo periodika v rámci svazku

May : 890171

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

15

Strana od-do

nestránkováno

Kód UT WoS článku

000803549000001

EID výsledku v databázi Scopus

2-s2.0-85131153282