The earliest Cambrian record of animals and ocean geochemical change

  title={The earliest Cambrian record of animals and ocean geochemical change},
  author={Adam C. Maloof and Susannah M. Porter and John L. Moore and Francis Ő. Dudás and Samuel A. Bowring and John A Higgins and David A. Fike and Michael P. Eddy},
  journal={Geological Society of America Bulletin},
  • A. MaloofS. Porter M. Eddy
  • Published 1 November 2010
  • Environmental Science, Geography
  • Geological Society of America Bulletin
The Cambrian diversification of animals was long thought to have begun with an explosive phase at the start of the Tommotian Age. Recent stratigraphic discoveries, however, suggest that many taxa appeared in the older Nemakit-Daldynian Age, and that the diversification was more gradual. We map lowest Cambrian (Nemakit-Daldynian through Tommotian) records of δ 13 C CaCO 3 variability from Siberia, Mongolia, and China onto a Moroccan U/Pb–δ 13 C CaCO 3 age model constrained by five U/Pb ages from… 

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