Rapid extensional unroofing of a granite-migmatite dome with relics of high-pressure rocks, the Podolsko complex, Bohemian Massif

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F17%3A10392426" target="_blank" >RIV/00216208:11310/17:10392426 - isvavai.cz</a>

Alternative codes found

RIV/67985831:_____/17:00475313

Result on the web

<a href="https://doi.org/10.1017/S0016756816000030" target="_blank" >https://doi.org/10.1017/S0016756816000030</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1017/S0016756816000030" target="_blank" >10.1017/S0016756816000030</a>

Result language

angličtina

Original language name

Rapid extensional unroofing of a granite-migmatite dome with relics of high-pressure rocks, the Podolsko complex, Bohemian Massif

Original language description

The Podolsko complex, Bohemian Massif, is a high-grade dome that is exposed along the suprastructure-infrastructure boundary of the Variscan orogen and records snapshots of its protracted evolution. The dome is cored by leucocratic migmatites and anatectic granites that enclose relics of high- to ultrahigh-pressure rocks and is mantled by biotite migmatites and paragneisses whose degree of anatexis decreases outwards. Our new U-Pb zircon ages indicate that the leucocratic migmatites were derived from Early Ordovician (c. 480 Ma) felsic igneous crust; the same age is inferred for melting the proto-source of the metapelitic migmatites. The relics of high- to ultrahigh-pressure rocks suggest that at least some portions of the complex witnessed an early Variscan subduction to mantle depths, followed by high-temperature anatexis and syntectonic growth of the Podolsko dome in the middle crust at c. 340-339 Ma. Subsequently, the dome exhumation was accommodated by crustal-scale extensional detachments. Similar c. 340 Ma ages have also been reported from other segments of the Variscan belt, yet the significance of this tectonothermal event remains uncertain. Here we conclude that the 340 Ma age post-dates the high-pressure metamorphism; the high temperatures required to cause the observed isotopic resetting and new growth of zircon were probably caused by heat input from the underlying mantle and, finally, the extensional unroofing of the complex requires a minimum throw of about 8-10 km. We use this as an argument for significant early Carboniferous palaeotopography in the interior of the Variscan orogen.

Czech name

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Czech description

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Type

J_imp - 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

Project

—

Continuities

S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

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

Name of the periodical

Geological Magazine

ISSN

0016-7568

e-ISSN

—

Volume of the periodical

154

Issue of the periodical within the volume

2

Country of publishing house

GB - UNITED KINGDOM

Number of pages

27

Pages from-to

354-380

UT code for WoS article

000395444700009

EID of the result in the Scopus database

2-s2.0-84957798134