Overview
Research indicates that a rare CO chondrite meteorite was the likely impacter that struck Earth 66 million years ago. This event is associated with the extinction of 75% of species on Earth, a group that includes nonavian dinosaurs. The identification was achieved through advanced nickel isotope analysis of meteorite samples.
Research Context
The Cretaceous-Paleogene extinction event, occurring 66 million years ago, led to the demise of a significant portion of Earth's species. The geological record indicates a major impact event around this period. Pinpointing the exact type of meteorite involved in this extinction has been a subject of scientific investigation. The current study focused on narrowing down the composition of the meteorite responsible for this global event.
Approach
The researchers utilized advanced nickel isotope analysis as their primary method. This analytical technique was applied to samples of meteorites. The aim of this analysis was to determine chemical signatures that could be linked to the specific type of meteorite responsible for the Cretaceous-Paleogene impact. Researchers from the University of British Columbia (UBC), Paris, Brussels, and Vienna collaborated on this study.
Findings
- Advanced nickel isotope analysis of samples revealed characteristics consistent with a CO chondrite meteorite.
- The analysis suggests that a rare CO chondrite meteorite was the probable impacter during the Cretaceous-Paleogene period.
- This impact event, occurring 66 million years ago, is linked to the extinction of approximately 75% of Earth's species, including nonavian dinosaurs.
Why This Matters
The identification of the specific meteorite class provides a more precise understanding of the celestial body responsible for a major extinction event in Earth's history. This information contributes to a more complete reconstruction of the Cretaceous-Paleogene boundary events and the mechanisms driving mass extinctions.