An extraterrestrial trigger for the mid-Ordovician ice age: dust from the breakup of the L-chondrite parent body
Schmitz, B.; Farley, K.A.; Goderis, S.; Heck, P.R.; Bergström, S.M.; Boschi, S.; Claeys, P.; Debaille, V.; Dronov, A.; van Ginneken, M.; Harper, D.A.T.; Iqbal, F.; Friberg, J.; Liao, S.; Martin, E.; Meier, M.M.M.; Peucker-Ehrenbrink, B.; Soens, B.; Wieler, R.; Terfelt, F. (2019). An extraterrestrial trigger for the mid-Ordovician ice age: dust from the breakup of the L-chondrite parent body. Science Advances 5(9): eaax4184. https://hdl.handle.net/10.1126/sciadv.aax4184 In: Science Advances. AAAS: New York. e-ISSN 2375-2548, more |   |
| Authors | | Top | - Schmitz, B.
- Farley, K.A.
- Goderis, S., more
- Heck, P.R.
- Bergström, S.M.
- Boschi, S.
- Claeys, P., more
| - Debaille, V., more
- Dronov, A.
- van Ginneken, M., more
- Harper, D.A.T.
- Iqbal, F.
- Friberg, J.
- Liao, S.
| - Martin, E.
- Meier, M.M.M.
- Peucker-Ehrenbrink, B.
- Soens, B., more
- Wieler, R.
- Terfelt, F.
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| Abstract | The breakup of the L-chondrite parent body in the asteroid belt 466 million years (Ma) ago still delivers almost a third of all meteorites falling on Earth. Our new extraterrestrial chromite and 3He data for Ordovician sediments show that the breakup took place just at the onset of a major, eustatic sea level fall previously attributed to an Ordovician ice age. Shortly after the breakup, the flux to Earth of the most fine-grained, extraterrestrial material increased by three to four orders of magnitude. In the present stratosphere, extraterrestrial dust represents 1% of all the dust and has no climatic significance. Extraordinary amounts of dust in the entire inner solar system during >2 Ma following the L-chondrite breakup cooled Earth and triggered Ordovician icehouse conditions, sea level fall, and major faunal turnovers related to the Great Ordovician Biodiversification Event. |
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