Reversed deep-sea carbonate ion basin gradient during Paleocene-Eocene thermal maximum
Article first published online: 14 JUL 2007
Copyright 2007 by the American Geophysical Union.
Volume 22, Issue 3, September 2007
How to Cite
2007), Reversed deep-sea carbonate ion basin gradient during Paleocene-Eocene thermal maximum, Paleoceanography, 22, PA3201, doi:10.1029/2006PA001395., and (
- Issue published online: 14 JUL 2007
- Article first published online: 14 JUL 2007
- Manuscript Accepted: 15 FEB 2007
- Manuscript Revised: 6 FEB 2007
- Manuscript Received: 18 NOV 2006
- carbon cycling;
- sediment modeling
 The Paleocene-Eocene thermal maximum (PETM, ∼55 Ma ago) was marked by widespread CaCO3 dissolution in deep-sea sediments, a process that has been attributed to massive release of carbon into the ocean-atmosphere system. The pattern of carbonate dissolution is key to reconstructing changes in deep sea carbonate chemistry and, ultimately, the rate, magnitude, and location of carbon input. Here we show that during the PETM, the deep-sea undersaturation was not homogeneous among the different ocean basins. Application of a sediment model to a suite of data records from different sites and ocean basins shows that a globally uniform decrease in deep-sea carbonate ion concentration ([CO32−]) is inconsistent with the data. Rather, we demonstrate that deep-sea [CO32−] increased from the Atlantic through the Southern Ocean into the Pacific. Our results show that the PETM deep-sea [CO32−] basin gradient during dissolution was reversed relative to the modern.