Skip to Main content Skip to Navigation
Journal articles

Chromium isotope evidence in ejecta deposits for the nature of Paleoproterozoic impactors

Abstract : 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 (Graensesø) and Russia (Zaonega), as well as some distal ejecta deposits (Lake Superior region) from the Sudbury impact (1,849±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 Graensesø and Zaonega spherule layers contain a distinct carbonaceous chondrite component, and are possibly related to the same impact event, which could be Vredefort (2,023±4 Ma) or another not yet identified large impact event 2 from that of similar age, and 3) the Sudbury ejecta record a complex meteoritic signature, which is different from the Graensesø and Zaonega spherule layers, and could indicate the impact of a heterogeneous chondritic body.
Complete list of metadatas

Cited literature [35 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-02917511
Contributor : Eva Fareau <>
Submitted on : Thursday, August 20, 2020 - 10:30:49 AM
Last modification on : Tuesday, September 1, 2020 - 3:06:16 AM

File

1612.06922.pdf
Files produced by the author(s)

Identifiers

Collections

Citation

Bérengère Mougel, Frédéric Moynier, Christa Göpel, Christian Koeberl. Chromium isotope evidence in ejecta deposits for the nature of Paleoproterozoic impactors. Earth and Planetary Science Letters, Elsevier, 2017, 460, pp.105-111. ⟨10.1016/j.epsl.2016.12.008⟩. ⟨insu-02917511⟩

Share

Metrics

Record views

19

Files downloads

35