Ocean acidification and the Permo-Triassic mass extinction

Science. 2015 Apr 10;348(6231):229-32. doi: 10.1126/science.aaa0193.


Ocean acidification triggered by Siberian Trap volcanism was a possible kill mechanism for the Permo-Triassic Boundary mass extinction, but direct evidence for an acidification event is lacking. We present a high-resolution seawater pH record across this interval, using boron isotope data combined with a quantitative modeling approach. In the latest Permian, increased ocean alkalinity primed the Earth system with a low level of atmospheric CO2 and a high ocean buffering capacity. The first phase of extinction was coincident with a slow injection of carbon into the atmosphere, and ocean pH remained stable. During the second extinction pulse, however, a rapid and large injection of carbon caused an abrupt acidification event that drove the preferential loss of heavily calcified marine biota.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aquatic Organisms*
  • Atmosphere
  • Boron
  • Carbon Cycle
  • Carbon Isotopes
  • Carbon*
  • Ecosystem
  • Extinction, Biological*
  • Hydrogen-Ion Concentration
  • Isotopes
  • Oceans and Seas
  • Seawater / chemistry*
  • Time


  • Carbon Isotopes
  • Isotopes
  • Carbon
  • Boron