Formation of the ‘Great Unconformity’ as a trigger for the Cambrian explosion

  title={Formation of the ‘Great Unconformity’ as a trigger for the Cambrian explosion},
  author={Shanan E. Peters and Robert R. Gaines},
  • S. PetersR. Gaines
  • Published 19 April 2012
  • Geology, Environmental Science, Geography
  • Nature
The transition between the Proterozoic and Phanerozoic eons, beginning 542 million years (Myr) ago, is distinguished by the diversification of multicellular animals and by their acquisition of mineralized skeletons during the Cambrian period. Considerable progress has been made in documenting and more precisely correlating biotic patterns in the Neoproterozoic–Cambrian fossil record with geochemical and physical environmental perturbations, but the mechanisms responsible for those perturbations… 

Neoproterozoic glacial origin of the Great Unconformity

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N eoproterozoic glacial origin of the G reat U nconformity

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Thermochronologic constraints on the origin of the Great Unconformity

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Diachronous development of Great Unconformities before Neoproterozoic Snowball Earth

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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

Geochemical evidence for widespread euxinia in the Later Cambrian ocean

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Exceptionally preserved fossil biotas of the Burgess Shale and a handful of other similar Cambrian deposits provide rare but critical insights into the early diversification of animals. The

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Knowledge of past rates of transfer of rock‐forming materials among the principal geologic reservoirs is central to understanding causes and magnitudes of change in earth surface processes over

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The concept of major rock-stratigraphic units of interregional scope was introduced in 1948 (Longwell, 1949). It is now possible to restate the concept and to define more explicitly the sequences

Devonian rise in atmospheric oxygen correlated to the radiations of terrestrial plants and large predatory fish

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Fieldwork of C. D. Walcott during his U.S. Geological Survey career may be artificially divided into two, intertwined segments, an earlier one concerned mainly with Paleozoic beds, but especially the