Importance of crustal relamination in origin of the orogenic mantle peridotite–high-pressure granulite association: example from the Náměšť Granulite Massif (Bohemian Massif, Czech Republic)

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F15%3A00000187" target="_blank" >RIV/00025798:_____/15:00000187 - isvavai.cz</a>

Alternative codes found

RIV/67985530:_____/15:00444174

Result on the web

<a href="http://jgs.lyellcollection.org/content/172/4/479.full.pdf+html" target="_blank" >http://jgs.lyellcollection.org/content/172/4/479.full.pdf+html</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1144/jgs2014-070" target="_blank" >10.1144/jgs2014-070</a>

Result language

angličtina

Original language name

Importance of crustal relamination in origin of the orogenic mantle peridotite–high-pressure granulite association: example from the Náměšť Granulite Massif (Bohemian Massif, Czech Republic)

Original language description

A characteristic association of crustal and mantle rocks is commonly used to decipher processes at the mantle– crust interface of HP–UHP collisional orogenic systems. Also, in the Variscan orogenic root of the Bohemian Massif (the Moldanubian Zone), high-pressure felsic granulites are often accompanied by spinel or garnet peridotites. This association was investigated using petrography, zircon geochronology and whole-rock geochemical data from the Náměšť Granulite Massif. The geochemical signature of the granulite is the same as for other Moldanubian occurrences, suggesting nearly isochemically metamorphosed felsic metaigneous rocks of Saxothuringian provenance. SHRIMP zircon dating yielded two main age maxima, at 395.2 ± 4.4 and 337.2 ± 1.7 Ma, reflecting an Early Devonian protolith and Visean HP metamorphism. As shown by Sr–Nd isotopic data, the variably refertilized harzburgite or depleted lherzolite was variously contaminated by mature crustal material resembling the studied granulites. To account for the origin of these HT–HP rock associations we suggest a new geotectonic model. An eastward continental subduction of Early Palaeozoic felsic metaigneous material of Saxothuringian origin was followed by its relamination at the bottom of the autochthonous lower crust. Ascending felsic granulites derived from the relaminated lower plate material sampled refertilized harzburgites originally formed in a backarc. The complete assemblage was subsequently exhumed, forming large, diapir-like bodies.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

DB - Geology and mineralogy

OECD FORD branch

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Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2015

Confidentiality

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

Name of the periodical

Journal of the Geological Society London

ISSN

0016-7649

e-ISSN

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Volume of the periodical

172

Issue of the periodical within the volume

4

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

479– 490

UT code for WoS article

000356630500006

EID of the result in the Scopus database

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