Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Postimpact earliest Paleogene warming shown by fish debris oxygen isotopes (El Kef, Tunisia)

75 views

Published on

Greenhouse warming is a predicted consequence of the Chicxulub impact, but supporting data are sparse. This shortcoming compromises understanding of the impact’s effects, and it has persisted due to an absence of sections that both contain suitable material for traditional carbonate-based or organic-based paleothermometry and are complete and expanded enough to resolve changes on short time scales. We address the problem by analyzing the oxygen isotopic composition of fish debris, phosphatic microfossils that are relatively resistant to diagenetic alteration, from the Global Stratotype Section and Point for the Cretaceous/Paleogene boundary at El Kef, Tunisia. We report an ~1‰ decrease in δ18O values (~5°C warming) beginning at the boundary and spanning ~300 cm of section (~100,000 years). The pattern found matches expectations for impact-initiated greenhouse warming.

Published in: Science
  • Be the first to comment

  • Be the first to like this

Postimpact earliest Paleogene warming shown by fish debris oxygen isotopes (El Kef, Tunisia)

  1. 1. Cite as: K. G. MacLeod et al., Science 10.1126/science.aap8525 (2018). First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 1 δ δ δ onMay25,2018http://science.sciencemag.org/Downloadedfrom
  2. 2. First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 2 δ δ δ δ δ δ δ δ δ δ onMay25,2018http://science.sciencemag.org/Downloadedfrom
  3. 3. First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 3 δ δ onMay25,2018http://science.sciencemag.org/Downloadedfrom
  4. 4. First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 4 onMay25,2018http://science.sciencemag.org/Downloadedfrom
  5. 5. First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 5 onMay25,2018http://science.sciencemag.org/Downloadedfrom
  6. 6. First release: 24 May 2018 www.sciencemag.org (Page numbers not final at time of first release) 6 δ σ σ δ onMay25,2018http://science.sciencemag.org/Downloadedfrom
  7. 7. Postimpact earliest Paleogene warming shown by fish debris oxygen isotopes (El Kef, Tunisia) K. G. MacLeod, P. C. Quinton, J. Sepúlveda and M. H. Negra originally published online May 24, 2018published online May 24, 2018 ARTICLE TOOLS http://science.sciencemag.org/content/early/2018/05/24/science.aap8525 MATERIALS SUPPLEMENTARY http://science.sciencemag.org/content/suppl/2018/05/23/science.aap8525.DC1 REFERENCES http://science.sciencemag.org/content/early/2018/05/24/science.aap8525#BIBL This article cites 27 articles, 9 of which you can access for free PERMISSIONS http://www.sciencemag.org/help/reprints-and-permissions Terms of ServiceUse of this article is subject to the registered trademark of AAAS. is aScienceAmerican Association for the Advancement of Science. No claim to original U.S. Government Works. The title Science, 1200 New York Avenue NW, Washington, DC 20005. 2017 © The Authors, some rights reserved; exclusive licensee (print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for the Advancement ofScience onMay25,2018http://science.sciencemag.org/Downloadedfrom

×