Chromium isotope evidence in ejecta deposits for the nature of Paleoproterozoic impactors
- Autor(en)
- Bérengère Mougel, Frédéric Moynier, Christa Göpel, Christian Koeberl
- Abstrakt
Non-mass dependent chromium isotopic signatures have been successfully used to determine the presence and identification of extra-terrestrial materials in terrestrial impact rocks. Paleoproterozoic spherule layers from Greenland (Grænsesø) and Russia (Zaonega), as well as some distal ejecta deposits (Lake Superior region) from the Sudbury impact (1849±0.3 Ma) event, have been analyzed for their Cr isotope compositions. Our results suggest that 1) these distal ejecta deposits are all of impact origin, 2) the Grænsesø and Zaonega spherule layers contain a distinct carbonaceous chondrite component, and are possibly related to the same impact event, which could be Vredefort (2023±4 Ma) or another not yet identified large impact event from that of similar age, and 3) the Sudbury ejecta record a complex meteoritic signature, which is different from the Grænsesø and Zaonega spherule layers, and could indicate the impact of a heterogeneous chondritic body.
- Organisation(en)
- Department für Lithosphärenforschung
- Externe Organisation(en)
- Université Sorbonne-Paris-Cité, Université Paris VII - Paris-Diderot
- Journal
- Earth and Planetary Science Letters
- Band
- 460
- Seiten
- 105-111
- Anzahl der Seiten
- 7
- ISSN
- 0012-821X
- DOI
- https://doi.org/10.1016/j.epsl.2016.12.008
- Publikationsdatum
- 02-2017
- Peer-reviewed
- Ja
- ÖFOS 2012
- 105105 Geochemie
- Schlagwörter
- ASJC Scopus Sachgebiete
- Geochemistry and Petrology, Geophysics, Earth and Planetary Sciences (miscellaneous), Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/6e554ec0-0b6c-44d5-a74a-2d588d4d5dc4