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Fullerenes in the cretaceous-tertiary boundary layer
Summary
Fullerenes (C60) were found in Cretaceous-Tertiary (K-T) boundary soot samples. This suggests wildfires, not just asteroid impacts, may have produced these molecules at the K-T event.
Area of Science:
- Geochemistry
- Paleontology
- Organic Chemistry
Background:
- The Cretaceous-Tertiary (K-T) boundary marks a mass extinction event.
- Fullerenes, including C60, are complex carbon molecules.
- The origin of extraterrestrial or terrestrial fullerenes at the K-T boundary is debated.
Purpose of the Study:
- To analyze K-T boundary soot for fullerene content.
- To compare fullerene concentrations with those from terrestrial combustion.
- To investigate potential wildfire origins for K-T boundary fullerenes.
Main Methods:
- High-pressure liquid chromatography (HPLC) was used for separation.
- Ultraviolet-visible (UV-Vis) spectral analysis identified C60.
- Toluene extraction was employed for sample preparation.
Main Results:
- C60 was detected in K-T boundary soot from New Zealand sites.
- Fullerene concentrations ranged from 0.1 to 0.2 parts per million.
- Similar fullerene amounts were found in soot from common flames.
Conclusions:
- Fullerenes in K-T boundary layers could originate from wildfires.
- Wildfires associated with the K-T impact event are a plausible source.
- This challenges solely impact-driven explanations for K-T boundary fullerenes.
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