The Archean-Proterozoic boundary: 500 my of tectonic transition in Earth history

  title={The Archean-Proterozoic boundary: 500 my of tectonic transition in Earth history},
  author={Kent C. Condie and Craig O'Neill},
  journal={American Journal of Science},
  pages={775 - 790}
Changes in the solid Earth at the end of the Archean fall into two categories. First are those related to cooling of the mantle and include a decrease in both komatiite abundance and MgO content, a decrease in Ni/Fe ratio in banded iron formation, and increases in incompatible element ratios (such as Nb/Yb, La/Yb, Zr/Y, La/Sm and Gd/Yb) in non-arc type basalts. A second group of changes is related to the extraction of continental crust from the mantle and stabilization of major cratons at 2.7… 

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