An extraterrestrial trigger for the mid-Ordovician ice age: Dust from the breakup of the L-chondrite parent body

Research output: Contribution to journalArticle

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.

Details

Authors
Organisations
External organisations
  • California Institute of Technology
  • Vrije Universiteit Brussel (VUB)
  • University of Chicago
  • Ohio State University
  • Free University of Brussels (ULB)
  • Kazan Federal University
  • Durham University
  • Purple Mountain Observatory, Chinese Academy of Sciences
  • ETH Zürich
  • Woods Hole Oceanographic Institution
  • Geological Institute, Russian Academy of Sciences
  • Royal Belgian Institute of Natural Sciences
  • Lund University
  • Center for Excellence in Comparative Planetology, CAS
  • Natural History Museum St. Gallen
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Geology
Original languageEnglish
Article numbereaax4184
JournalScience Advances
Volume5
Issue number9
Publication statusPublished - 2019 Sep 18
Publication categoryResearch
Peer-reviewedYes