Geotectonic settings of Variscan explosive volcanism in the light of Famennian tuffites provenance from southern Poland

0563125 - GLÚ 2023 RIV NL eng J - Článek v odborném periodiku
Pisarzowska, A. - Paszkowski, M. - Kołtonik, K. - Budzyń, B. - Szczerba, M. - Rakociński, M. - Sláma, Jiří - Zagórska, A. - Łaptaś, A.
Geotectonic settings of Variscan explosive volcanism in the light of Famennian tuffites provenance from southern Poland.
Earth-Science Reviews. Roč. 234, November (2022), č. článku 104218. ISSN 0012-8252. E-ISSN 1872-6828
Institucionální podpora: RVO:67985831
Klíčová slova: Late Devonian volcanism * Tuffites * Whole-rock geochemistry * X-ray diffraction analysis * Zircon and monazite geochronology * Volcanic source
Obor OECD: Geology
Impakt faktor: 12.1, rok: 2022
Způsob publikování: Open access
https://www.sciencedirect.com/science/article/pii/S0012825222003026?via%3Dihub

Pyroclastic horizons are common in the middle–upper Famennian carbonate and siliceous successions located near the Rhenohercynian margins of Laurussia and the Variscian Saxothuringian oceanic realm. We present a detailed geochronological, geochemical and mineralogical study of tuffites from three sites in southern Poland: Holy Cross Mountains (Kowala), Krak´ow–Silesia monocline (Czatkowice, Dębnik anticline), and Sudetes (Bardo, Bardo Mountains). Airborne volcanic ash in Czatkowice was deposited on a shallow carbonate platform, in Kowala in the deeper intrashelf basin and tephra in Bardo in the deep pelagic basin below the carbonate compensation depth. The LA-ICP-MS U-Pb data demonstrate nearly uniform ages of zircon 365.6 ± 2.9 Ma and 363.0 ± 3.5 Ma for Czatkowice samples and monazite 363.4 ± 5.8 Ma and 363.1 ± 4.8 Ma for samples from Czatkowice and Kowala, respectively. Mineralogical and geochemical data showed the occurrence of two groups of Famennian tuffites in southern Poland, which are genetically related to different geotectonic realms. The predominantly rhyolitic–rhyodacitic–dacitic volcanogenic material from Kowala and Czatkowice results from within-plate effusive pyroclastic activity. The basalt–trachyandesite tuffites from Bardo were formed in an active plate margin setting connected with the Gondwana–Laurussia convergence, where processes of subduction and accretion of new crust occurred. The Late Devonian magmatic center belonging to the Pripyat–Dnieper– Donets–Donbas rift could be the most probable proximal source area for volcanic ash deposits in the Holy Cross Mountains and the Krak´ow–Silesia monocline. More distal sources could be late Devonian rift-related magmatism in the Dacia megaterrane or the Maritime magmatic province. In contrast, the source of the older volcanism generating the pyroclastic plume and deposits in the Bardo Mountain Basin could be related to the eruptive activity in the Moravian–Silesian Zone and/or magmatic centers in some Variscan terranes, which are now incorporated into the Alpine orogen.
Trvalý link: https://hdl.handle.net/11104/0335188