http://hdl.handle.net/20.500.12128/8814
Tytuł: | Cadomian protolith ages of exotic mega blocks from Bugaj and Andrychów (Western outer Carpathians, Poland) and their palaeogeographic significance |
Autor: | Burda, Jolanta Woskowicz-Ślęzak, Beata Klotzli, Urs Gawęda, Aleksandra |
Słowa kluczowe: | exotics; zircon U-Pb dating; Western Outer Carpathians; palaeogeography; Brunovistulicum |
Data wydania: | 2019 |
Źródło: | Geochronometria, Vol. 46, Iss. 1 (2019), s. 25-36 |
Abstrakt: | This study presents the first zircon U-Pb LA-MC-ICP-MS ages and whole-rock Rb/Sr and Sm/Nd data from exotic blocks (Bugaj and Andrychów) from the Western Outer Carpathians (WOC) flysch. The CL images of the zircon crystals from both samples reveal typical magmatic textures characterized by a well-defined concentric and oscillatory growth zoning. A concordia age 580.1 ± 6.0 Ma of the zircons from the Bugaj sample is considered to represent the crystallization age of this granite. The zircon crystals from the Andrychów orthogneiss yield an age of 542 ± 21 Ma, in-terpreted as the uppermost Proterozoic, magmatic crystallization age of the granitoid protholith. The initial (at ca. 580 Ma) 87Sr/86Sr ratios of the Bugaj granitoids (0.72997 and 0.72874) are highly radio-genic, pointing to the assimilation of an older, possibly strongly Rb enriched source to the Bugaj melt. The Nd isotope systematics (εNd580 –1.4 and 0.4) also point to a significant contribution of such a dis-tinct mantle source. On the basis of the sequence of magmatic events obtained from U-Pb zircon ages, we suggest that exotic mega blocks deposited to the WOC basins were related to the Brunovistulicum Terrane. They belong to the group of Vendian/Cambrian granitoids representing the latest, post-tectonic expression of the Cadomian cycle. |
URI: | http://hdl.handle.net/20.500.12128/8814 |
DOI: | 10.1515/geochr-2015-0102 |
ISSN: | 1897-1695 |
Pojawia się w kolekcji: | Artykuły (WNP) |
Plik | Opis | Rozmiar | Format | |
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Burda_Cadomian_protolith_ages_of_exotic_mega_blocks.pdf | 3,04 MB | Adobe PDF | Przejrzyj / Otwórz |
Uznanie autorstwa - użycie niekomercyjne, bez utworów zależnych 3.0 Polska Creative Commons