J. Blichert-Toft and F. Albarede (2007). "Hafnium isotopes in Jack Hills zircons and the formation of the Hadean crust." EARTH AND PLANET SCI LETT 265(3-4): 686-702.

One of the fundamental issues of Earth evolution is to understand when growth of continental crust began. Constraining this question will help us date the timing of onset of plate tectonics and thus ultimately the origin of life. We have addressed this problem by dating single Hadean zircons from Jack Hills in Western Australia and comparing their inferred geochemical properties with a variety of modern rock types (MORB, OIB, plateau basalts, subduction zone lavas etc.) in order to deduce the nature of the source rock of the Jack Hills granites. This approach, which was based on using real data of worldwide distribution from PetDB and which could not have been undertaken in such an efficient manner without access to this data base source, helped us exclude all modern candidates as the protolith of the Jack Hills granites and come up with a unique alternative explanation involving a ~4.35 Ga TTG-like (tonalite-trondhjemite-granodiorite) crust which itself may have been produced by melting of the last remains of the magma ocean. - J. Blichert-Toft

 

J. Blichert-Toft and F. Albarede (2007). "Hafnium isotopes in Jack Hills zircons and the formation of the Hadean crust." EARTH AND PLANET SCI LETT 265(3-4): 686-702.doi:10.1016/j.epsl.2007.10.054



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