Ruthenium isotopes show the Chicxulub impactor was a carbonaceous-type asteroid

Author(s)
Mario Fischer-Gödde, Jonas Tusch, Steven Goderis, Alessandro Bragagni, Tanja Mohr-Westheide, Nils Messling, Bo Magnus Elfers, Birger Schmitz, Wolf U. Reimold, Wolfgang D. Maier, Philippe Claeys, Christian Koeberl, François L.H. Tissot, Martin Bizzarro, Carsten Münker
Abstract

An impact at Chicxulub, Mexico, occurred 66 million years ago, producing a global stratigraphic layer that marks the boundary between the Cretaceous and Paleogene eras. That layer contains elevated concentrations of platinum-group elements, including ruthenium. We measured ruthenium isotopes in samples taken from three Cretaceous-Paleogene boundary sites, five other impacts that occurred between 36 million to 470 million years ago, and ancient 3.5-billion- to 3.2-billion-year-old impact spherule layers. Our data indicate that the Chicxulub impactor was a carbonaceous-type asteroid, which had formed beyond the orbit of Jupiter. The five other impact structures have isotopic signatures that are more consistent with siliceous-type asteroids, which formed closer to the Sun. The ancient spherule layer samples are consistent with impacts of carbonaceous-type asteroids during Earth's final stages of accretion.

Organisation(s)
Department of Lithospheric Research
External organisation(s)
Universität zu Köln, Vrije Universiteit Brussel, University of Florence, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, Museum für Naturkunde Berlin - Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Georg-August-Universität Göttingen, Technische Universität Hamburg-Harburg (TUHH), Lund University, Universidade Federal do Rio Grande do Sul, Universidade de Brasília, Cardiff University, California Institute of Technology (Caltech), University of Copenhagen
Journal
Science
Volume
385
Pages
752-756
No. of pages
5
ISSN
0036-8075
DOI
https://doi.org/10.1126/science.adk4868
Publication date
08-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105105 Geochemistry
ASJC Scopus subject areas
General
Portal url
https://ucrisportal.univie.ac.at/en/publications/7e6ab3dc-6b79-4258-bc70-63440535e4ca