Calibrating the Cryogenian

TitleCalibrating the Cryogenian
Publication TypeJournal Article
Year of Publication2010
AuthorsMacdonald F.A, Schmitz M.D, Crowley J.L, Roots C.F, Jones D.S, Maloof A.C, Strauss J.V, Cohen P.A, Johnston D.T, Schrag D.P
JournalScience
Volume327
Issue5970
Pagination1241
Date Published03/2010
Other Numbers19Maloof
Abstract

The Neoproterozoic was an era of great environmental and biological change, but a paucity of direct and precise age constraints on strata from this time has prevented the complete integration of these records. We present four high-precision U-Pb ages for Neoproterozoic rocks in northwestern Canada that constrain large perturbations in the carbon cycle, a major diversification and depletion in the microfossil record, and the onset of the Sturtian glaciation. A volcanic tuff interbedded with Sturtian glacial deposits, dated at 716.5 million years ago, is synchronous with the age of the Franklin large igneous province and paleomagnetic poles that pin Laurentia to an equatorial position. Ice was therefore grounded below sea level at very low paleolatitudes, which implies that the Sturtian glaciation was global in extent.

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URLhttps://doi.org/10.1126/science.1183325
DOI10.1126/science.1183325
Short TitleScience