Isotope fractionation and atmospheric oxygen: Implications for Phanerozoic O2 Evolution


Journal Article

Models describing the evolution of the partial pressure of atmospheric oxygen over Phanerozoic time are constrained by the mass balances required between the inputs and outputs of carbon and sulfur to the oceans. This constraint has limited the applicability of proposed negative feedback mechanisms for maintaining levels of atmospheric O(2) at biologically permissable levels. Here we describe a modeling approach that incorporates O(2)-dependent carbon and sulfur isotope fractionation using data obtained from laboratory experiments on carbon-13 discrimination by vascular land plants and marine plankton. The model allows us to calculate a Phanerozoic O(2) history that agrees with independent models and with biological and physical constraints and supports the hypothesis of a high atmospheric O(2) content during the Carboniferous (300 million years ago), a time when insect gigantism was widespread.

Full Text

Duke Authors

Cited Authors

  • Berner, RA; Petsch, ST; Lake, JA; Beerling, DJ; Popp, BN; Lane, RS; Laws, EA; Westley, MB; Cassar, N; Woodward, FI; Quick, WP

Published Date

  • March 2000

Published In

Volume / Issue

  • 287 / 5458

Start / End Page

  • 1630 - 1633

PubMed ID

  • 10698733

Pubmed Central ID

  • 10698733

Electronic International Standard Serial Number (EISSN)

  • 1095-9203

International Standard Serial Number (ISSN)

  • 0036-8075

Digital Object Identifier (DOI)

  • 10.1126/science.287.5458.1630


  • eng