Heterogeneous Hadean Hafnium: Evidence of Continental Crust at 4.4 to 4.5 Ga

@article{Harrison2005HeterogeneousHH,
  title={Heterogeneous Hadean Hafnium: Evidence of Continental Crust at 4.4 to 4.5 Ga},
  author={T. Mark Harrison and Janne Blichert‐Toft and Wolfgang M{\"u}ller and Francis Albar{\`e}de and Peter Holden and Stephen J. Mojzsis},
  journal={Science},
  year={2005},
  volume={310},
  pages={1947 - 1950}
}
The long-favored paradigm for the development of continental crust is one of progressive growth beginning at ∼4 billion years ago (Ga). To test this hypothesis, we measured initial 176Hf/177Hf values of 4.01- to 4.37-Ga detrital zircons from Jack Hills, Western Australia. ϵHf (deviations of 176Hf/177Hf from bulk Earth in parts per 104) values show large positive and negative deviations from those of the bulk Earth. Negative values indicate the development of a Lu/Hf reservoir that is consistent… 
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