Assembly of the Variscan Orogenic Wedge in the Bohemian Massif: Monazite U-Pb Geochronology of the Tectonic Events Recorded in Saxothuringian Metasediments
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F23%3A10473417" target="_blank" >RIV/00216208:11310/23:10473417 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=ld13iYUM6q" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=ld13iYUM6q</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1029/2022TC007626" target="_blank" >10.1029/2022TC007626</a>
Alternative languages
Result language
angličtina
Original language name
Assembly of the Variscan Orogenic Wedge in the Bohemian Massif: Monazite U-Pb Geochronology of the Tectonic Events Recorded in Saxothuringian Metasediments
Original language description
The geochronology of metasediments incorporated to orogenic wedges provides an important key in understanding the early evolution of collisional systems. This study reveals the timing of Variscan processes in the Saxothuringian orogenic wedge, reflecting transition from oceanic to continental subduction and collision. In situ monazite U-Pb geochronology and Rare Earth Elements (REE) geochemistry were performed in the Erzgebirge Crystalline Complex on phyllites and micaschists surrounding the ultra-high-pressure (UHP) core of the Erzgebirge dome. The resulting ages and REE patterns were linked to the individual tectonometamorphic events and revealed that the hanging-wall phyllites experienced prograde metamorphism around ~350 Ma, followed by exhumation at ~345-340 Ma. The oldest age (~339 Ma) recorded in garnet cores in the foot-wall micaschists is considered as an upper age limit for their prograde metamorphism, while matrix monazite ages of ~330 Ma reflect a significant resetting of the monazite age system. Spatial distribution of metamorphic isograds and ages indicates a phase of accretion of continental material resulting in an inverted metamorphic field gradient in the wedge between ~360 and ~340 Ma. This phase was followed by exhumation of a significant portion of buoyant subducted continental material leading to massive ductile thinning of the wedge around ~335 Ma. Finally, a late Variscan intracontinental deformation was responsible for heterogeneous reactivation and final exhumation of the wedge at ~330 Ma. It is newly shown that the Saxothuringian wedge can be divided into a younger inner part, formed by micaschists and UHP rocks, and an older outer part, formed by phyllites.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10505 - Geology
Result continuities
Project
<a href="/en/project/GA17-22207S" target="_blank" >GA17-22207S: The role of inherited continental margin architecture on early Variscan convergence</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2023
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Tectonics
ISSN
0278-7407
e-ISSN
1944-9194
Volume of the periodical
42
Issue of the periodical within the volume
4
Country of publishing house
US - UNITED STATES
Number of pages
29
Pages from-to
e2022TC007626
UT code for WoS article
000973431700001
EID of the result in the Scopus database
2-s2.0-85153865589