Thermochronological constraints on the post-Variscan exhumation history of the southeastern Bohemian Massif (Waldviertel and Weinsberg Forest, Austria): palaeogeographic and geomorphologic implications

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00131377" target="_blank" >RIV/00216224:14310/23:00131377 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1007/s00531-023-02294-6" target="_blank" >https://doi.org/10.1007/s00531-023-02294-6</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00531-023-02294-6" target="_blank" >10.1007/s00531-023-02294-6</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Thermochronological constraints on the post-Variscan exhumation history of the southeastern Bohemian Massif (Waldviertel and Weinsberg Forest, Austria): palaeogeographic and geomorphologic implications

Popis výsledku v původním jazyce

Resolving the Mesozoic and Cenozoic palaeogeography and geomorphologic development of outcropping Variscan basement is a pre-condition for the understanding of central European geodynamics. For our study, we have applied apatite fission-track (AFT) and apatite (U-Th)/He (AHe) thermochronology to surface rocks of the southeastern Bohemian Massif. 46 samples were examined by the AFT method. Additional AHe dating was applied to 8 of them. The AFT ages range from 251 +/- 46 to 60.2 +/- 4.8 Ma. AHe ages range from 25 to 525 Ma with rather high intra-sample scatter. On a regional scale, the AFT ages generally decrease from mainly late Variscan in the NE to Late Cretaceous and Paleocene in the SW. This regional age asymmetry relative to the NW-SE trending watershed of the Weinsberg Forest is neither compatible with regional uplift of a single block nor with large-scale lithospheric updoming. The lack of age breaks along late Variscan faults demonstrates that strong vertical offset cannot have occurred in Cretaceous and Cenozoic times. Inverse modeling of thermochronological data indicates regional Early Cretaceous cooling and subsequent reheating during the Late Cretaceous. Rocks of the present-day surface were heated up to a temperature of ca. 80 degrees C without full reset of the AFT system. This thermal history is compatible with the existence of a large mainland in Early Cretaceous times and a subsequent sedimentary reburial until the Campanian on the order of up to 1 km overburden. Parts of the exhumed weathering basal relief to the N and NE of the Weinsberg Forest are inherited as 'sealed relief' from Middle Cretaceous time. The observed regional asymmetry of AFT data is best explained by the development of a continental escarpment adjacent to the North Penninic Ocean in latest Cretaceous to Paleogene times. A final episode of accelerated cooling after ca. 20 Ma, as indicated by thermochronological modeling, is tentatively ascribed to either collisional coupling of the Alpine-Carpathian nappe pile with its northern foreland or to East-Alpine slab detachment.

Název v anglickém jazyce

Thermochronological constraints on the post-Variscan exhumation history of the southeastern Bohemian Massif (Waldviertel and Weinsberg Forest, Austria): palaeogeographic and geomorphologic implications

Popis výsledku anglicky

Resolving the Mesozoic and Cenozoic palaeogeography and geomorphologic development of outcropping Variscan basement is a pre-condition for the understanding of central European geodynamics. For our study, we have applied apatite fission-track (AFT) and apatite (U-Th)/He (AHe) thermochronology to surface rocks of the southeastern Bohemian Massif. 46 samples were examined by the AFT method. Additional AHe dating was applied to 8 of them. The AFT ages range from 251 +/- 46 to 60.2 +/- 4.8 Ma. AHe ages range from 25 to 525 Ma with rather high intra-sample scatter. On a regional scale, the AFT ages generally decrease from mainly late Variscan in the NE to Late Cretaceous and Paleocene in the SW. This regional age asymmetry relative to the NW-SE trending watershed of the Weinsberg Forest is neither compatible with regional uplift of a single block nor with large-scale lithospheric updoming. The lack of age breaks along late Variscan faults demonstrates that strong vertical offset cannot have occurred in Cretaceous and Cenozoic times. Inverse modeling of thermochronological data indicates regional Early Cretaceous cooling and subsequent reheating during the Late Cretaceous. Rocks of the present-day surface were heated up to a temperature of ca. 80 degrees C without full reset of the AFT system. This thermal history is compatible with the existence of a large mainland in Early Cretaceous times and a subsequent sedimentary reburial until the Campanian on the order of up to 1 km overburden. Parts of the exhumed weathering basal relief to the N and NE of the Weinsberg Forest are inherited as 'sealed relief' from Middle Cretaceous time. The observed regional asymmetry of AFT data is best explained by the development of a continental escarpment adjacent to the North Penninic Ocean in latest Cretaceous to Paleogene times. A final episode of accelerated cooling after ca. 20 Ma, as indicated by thermochronological modeling, is tentatively ascribed to either collisional coupling of the Alpine-Carpathian nappe pile with its northern foreland or to East-Alpine slab detachment.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/EF16_026%2F0008459" target="_blank" >EF16_026/0008459: Dlouhodobý výzkum geochemických bariér pro ukládání jaderného odpadu</a><br>

Návaznosti

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

Rok uplatnění

2023

Kód důvěrnosti údajů

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

Název periodika

International Journal of Earth Sciences

ISSN

1437-3254

e-ISSN

1437-3262

Svazek periodika

112

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

24

Strana od-do

1203-1226

Kód UT WoS článku

000930961800001

EID výsledku v databázi Scopus

2-s2.0-85148070134