Publication detail

Lead isotope evolution of the Central European upper mantle: Constraints from the Bohemian Massif

KRMÍČKOVÁ, S. KRMÍČEK, L. ROMER, R.L. ULRYCH, J.

Original Title

Lead isotope evolution of the Central European upper mantle: Constraints from the Bohemian Massif

Type

journal article in Web of Science

Language

English

Original Abstract

The Pb isotope composition of the upper mantle beneath Central Europe is heterogeneous due to the subduction of regionally contrasting material during the Variscan and Alpine orogenies. Late Variscan to Cenozoic mantle-derived melts allow mapping this heterogeneity on a regional scale for the last ca. 340 Myr. Late Cretaceous and Cenozoic anorogenic magmatic rocks of the Bohemian Massif (lamprophyres, volcanic rocks of basanite/tephrite and trachyte/phonolite series) concentrate mostly in the Eger Rift. Cretaceous ultramafic lamprophyres yielded the most radiogenic Pb isotope signatures reflecting a maximum contribution from metasomatised lithospheric mantle, whereas Tertiary alkaline lamprophyres originated from mantle with less radiogenic Pb-206/Pb-204 ratios suggesting a more substantial modification of lithospheric source by interaction with asthenospheric-derived melts. Cenozoic volcanic rocks of the basanite/tephrite and trachyte/phonolite series define a linear mixing trend between these components, indicating dilution of the initial lithospheric mantle signature by up-welling asthenosphere during rifting. The Pb isotope composition of Late Cretaceous and Cenozoic magmatic rocks of the Bohemian Massif follows the same Pb growth curve as Variscan orogenic lamprophyres and lamproites that formed during the collision between Laurussia, Gondwana, and associated terranes. This implies that the crustal Pb signature in the post-Variscan mantle is repeatedly sampled by younger anorogenic melts. Most Cenozoic mantle-derived rocks of Central Europe show similar Pb isotope ranges as the Bohemian Massif.

Keywords

Lead isotopes; Lamprophyres; Volcanic rocks; Mantle components; Bohemian massif; Variscan orogeny

Authors

KRMÍČKOVÁ, S.; KRMÍČEK, L.; ROMER, R.L.; ULRYCH, J.

Released

15. 5. 2020

Publisher

CHINA UNIV GEOSCIENCES, BEIJING

Location

Peking

ISBN

1674-9871

Periodical

Geoscience Frontiers

Year of study

11

Number

3

State

People's Republic of China

Pages from

925

Pages to

942

Pages count

18

URL

https://www.sciencedirect.com/science/article/pii/S1674987119301744

Full text in the Digital Library

http://hdl.handle.net/11012/193490

BibTex

@article{BUT164482,
  author="Simona {Krmíčková} and Lukáš {Krmíček} and Rolf L. {Romer} and Jaromír {Ulrych}",
  title="Lead isotope evolution of the Central European upper mantle: Constraints from the Bohemian Massif",
  journal="Geoscience Frontiers",
  year="2020",
  volume="11",
  number="3",
  pages="925--942",
  doi="10.1016/j.gsf.2019.09.009",
  issn="1674-9871",
  url="https://www.sciencedirect.com/science/article/pii/S1674987119301744"
}