Review abstract
Nature Geoscience 1, 817 - 825 (2008)
Published online: 30 November 2008 | doi:10.1038/ngeo355
Subject Categories: Palaeoclimate and palaeoceanography | Cryospheric science
Sedimentary challenge to Snowball Earth
Philip A. Allen1 & James L. Etienne2
Abstract
Evidence from the magnetic field fossilized in sedimentary rocks suggests that, more than 600 million years ago, ice occupied tropical latitudes. A popular explanation for these findings, the Snowball Earth concept, envisages a fully frozen Earth for millions of years, caused by a runaway ice–albedo feedback. A rapid, catastrophic meltback at very high levels of atmospheric carbon dioxide is thought to have ended this extreme climatic state. However, sedimentary rocks deposited during these cold intervals indicate that dynamic glaciers and ice streams continued to deliver large amounts of sediment to open oceans throughout the glacial cycle. The sedimentary evidence therefore indicates that despite the severity of glaciation, some oceans must have remained ice-free. Significant areas of open ocean have important implications for the survival and diversification of life and for the workings of the global carbon cycle.
-
Department of Earth Science & Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
e-mail: philip.allen@imperial.ac.uk -
Neftex Petroleum Consultants Ltd, 97 Milton Park, Abingdon, Oxfordshire OX14 4RY, UK.
e-mail: james.etienne@neftex.com
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
NEWS AND VIEWS
Palaeontology Extinction before the snowballNature Geoscience News and Views (01 Jun 2009)
Earth science Gas hydrates and deglaciationsNature News and Views (16 Aug 2001)
See all 5 matches for News And ViewsRESEARCH
Snowball Earth prevention by dissolved organic carbon remineralizationNature Article (06 Dec 2007)
Oxidation of the Ediacaran OceanNature Letters to Editor (07 Dec 2006)
See all 15 matches for Research
