.sup.40./sup.Ar/.sup.39./sup.Ar step-heating dating of phlogopite and kaersutite megacrysts from the Železná hůrka (Eisenbühl) Pleistocene scoria cone, Czech Republic

0534170 - GLÚ 2021 RIV SK eng J - Článek v odborném periodiku
Krmíček, Lukáš - Timmerman, M. J. - Ziemann, M. A. - Sudo, M. - Ulrych, Jaromír
⁴⁰Ar/³⁹Ar step-heating dating of phlogopite and kaersutite megacrysts from the Železná hůrka (Eisenbühl) Pleistocene scoria cone, Czech Republic.
Geologica Carpathica. Roč. 71, č. 4 (2020), s. 382-387. ISSN 1335-0552. E-ISSN 1336-8052
Institucionální podpora: RVO:67985831
Klíčová slova: Bohemian Massif * Železná hůrka * Eisenbühl * argon dating * mica * amphibole * melilitite
Obor OECD: Geology
Impakt faktor: 1.875, rok: 2020
Způsob publikování: Open access
http://www.geologicacarpathica.com/browse-journal/volumes/71-4/article-954/

⁴⁰Ar/³⁹Ar step-heating of mica and amphibole megacrysts from hauyne-bearing olivine melilitite scoria/tephra from the Železná hůrka yielded a 435±108 ka isotope correlation age for phlogopite and a more imprecise 1.55 Ma total gas age of the kaersutite megacryst. The amphibole megacrysts may constitute the first, and the younger phlogopite megacrysts the later phase of mafic, hydrous melilitic magma crystallization. It cannot be ruled out that the amphibole megacrysts are petrogenetically unrelated to tephra and phlogopite megacrysts and were derived from mantle xenoliths or disaggregated older, deep crustal pegmatites. This is in line both with the rarity of amphibole at Železná hůrka and with the observed signs of magmatic resorption at the edges of amphibole crystals.
Trvalý link: http://hdl.handle.net/11104/0312531