Polycyclic Andean-type orogenic evolution of the Dunhuang block in NW China: A result of Paleozoic reconfiguration of oceanic subduction systems

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F25%3A10169568" target="_blank" >RIV/00025798:_____/25:10169568 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1016/j.earscirev.2024.104984" target="_blank" >https://doi.org/10.1016/j.earscirev.2024.104984</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.earscirev.2024.104984" target="_blank" >10.1016/j.earscirev.2024.104984</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Polycyclic Andean-type orogenic evolution of the Dunhuang block in NW China: A result of Paleozoic reconfiguration of oceanic subduction systems

Popis výsledku v původním jazyce

Despite numerous studies of metamorphic and magmatic rocks from the Dunhuang block, its protracted Cambrian to Permian geodynamic evolution as well as its role in the final amalgamation of the Tarim-North- China Craton Collage during the Pangea assembly, remain controversial. In order to understand the evolution of the Dunhuang block in the frame of Paleozoic plate tectonics, we review and synthetize recently published P-T data along with geochronological and geochemical data for its northern, central and southern mountain ranges, which we placed in the context of structural observations. Zircon and monazite U-Pb ages combined with P-T constraints determined for Ordovician to Devonian metamorphic rocks reveal that M1 and M2 metamorphic events define a clockwise P-T evolution and distinctly hot metamorphic gradients. Ordovician to Devonian protracted garnet growth evidenced by low (Yb/Gd)N ratios in metamorphic zircon and monazite, together with low Th/U ratios, negative epsilon Hf(t) and Eu anomalies in magmatic and metamorphic zircon, mark a period of continuous metamorphism accompanied by crustal reworking during thickening of a previously thermally softened crust. Zircon and monazite U-Pb ages suggest that the early Paleozoic D1-M1 and D2-M2 events started ca. 10 m.y. earlier and lasted longer in the northern and central ranges compared to the southern range consisting of significantly older crustal basement components. In all three mountain ranges, the formation of an E-W trending steep cleavage related to D3-M3 event was concomitant with emplacement of numerous late Devonian to Carboniferous diorites and I-type granitoids. The negative epsilon Hf(t) of magmatic zircon and high (Yb/Gd)N ratios in metamorphic zircon and monazite show that a magma-assisted N-S-directed shortening event responsible for further crustal reworking started in the late Devonian and lasted over 60 m.y. The latest Permian M4 metamorphic event, restricted mainly to the southern range, defines anticlockwise P-T paths associated with the emplacement of high-K calc-alkaline granitoids. This event is characterized by the increasing from negative to positive zircon epsilon Hf(t) values, suggesting input of juvenile crustal and mantle-derived material. High metamorphic gradients and the petrogenesis of magmatic arc-related rocks intruding a Precambrian basement suggest that the Dunhuang block developed as a supra-subduction continental hot orogenic system formed above subducting oceanic plates similar to the northern and southern margins of the American Cordillera. Our data show that its evolution was related to two kinematically independent early to middle and late Paleozoic orogenic cycles. In the context of plate tectonic reconstructions, the revised chronology of events points to the kinematic interplay between the continental blocks moving within the Proto-Tethys oceanic domain in association with the south- dipping Panthalassa, Paleo-Asian, and north-dipping Paleo-Tethys oceanic subduction systems.

Název v anglickém jazyce

Polycyclic Andean-type orogenic evolution of the Dunhuang block in NW China: A result of Paleozoic reconfiguration of oceanic subduction systems

Popis výsledku anglicky

Despite numerous studies of metamorphic and magmatic rocks from the Dunhuang block, its protracted Cambrian to Permian geodynamic evolution as well as its role in the final amalgamation of the Tarim-North- China Craton Collage during the Pangea assembly, remain controversial. In order to understand the evolution of the Dunhuang block in the frame of Paleozoic plate tectonics, we review and synthetize recently published P-T data along with geochronological and geochemical data for its northern, central and southern mountain ranges, which we placed in the context of structural observations. Zircon and monazite U-Pb ages combined with P-T constraints determined for Ordovician to Devonian metamorphic rocks reveal that M1 and M2 metamorphic events define a clockwise P-T evolution and distinctly hot metamorphic gradients. Ordovician to Devonian protracted garnet growth evidenced by low (Yb/Gd)N ratios in metamorphic zircon and monazite, together with low Th/U ratios, negative epsilon Hf(t) and Eu anomalies in magmatic and metamorphic zircon, mark a period of continuous metamorphism accompanied by crustal reworking during thickening of a previously thermally softened crust. Zircon and monazite U-Pb ages suggest that the early Paleozoic D1-M1 and D2-M2 events started ca. 10 m.y. earlier and lasted longer in the northern and central ranges compared to the southern range consisting of significantly older crustal basement components. In all three mountain ranges, the formation of an E-W trending steep cleavage related to D3-M3 event was concomitant with emplacement of numerous late Devonian to Carboniferous diorites and I-type granitoids. The negative epsilon Hf(t) of magmatic zircon and high (Yb/Gd)N ratios in metamorphic zircon and monazite show that a magma-assisted N-S-directed shortening event responsible for further crustal reworking started in the late Devonian and lasted over 60 m.y. The latest Permian M4 metamorphic event, restricted mainly to the southern range, defines anticlockwise P-T paths associated with the emplacement of high-K calc-alkaline granitoids. This event is characterized by the increasing from negative to positive zircon epsilon Hf(t) values, suggesting input of juvenile crustal and mantle-derived material. High metamorphic gradients and the petrogenesis of magmatic arc-related rocks intruding a Precambrian basement suggest that the Dunhuang block developed as a supra-subduction continental hot orogenic system formed above subducting oceanic plates similar to the northern and southern margins of the American Cordillera. Our data show that its evolution was related to two kinematically independent early to middle and late Paleozoic orogenic cycles. In the context of plate tectonic reconstructions, the revised chronology of events points to the kinematic interplay between the continental blocks moving within the Proto-Tethys oceanic domain in association with the south- dipping Panthalassa, Paleo-Asian, and north-dipping Paleo-Tethys oceanic subduction systems.

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

2025

Kód důvěrnosti údajů

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

Název periodika

Earth-Science Reviews

ISSN

0012-8252

e-ISSN

1872-6828

Svazek periodika

261

Číslo periodika v rámci svazku

104984

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

27

Strana od-do

nestránkováno

Kód UT WoS článku

001391013900001

EID výsledku v databázi Scopus

2-s2.0-85212107368