Titanium isotopic evidence for felsic crust and plate tectonics 3.5 billion years ago.


Earth exhibits a dichotomy in elevation and chemical composition between the continents and ocean floor. Reconstructing when this dichotomy arose is important for understanding when plate tectonics started and how the supply of nutrients to the oceans changed through time. We measured the titanium isotopic composition of shales to constrain the chemical… (More)
DOI: 10.1126/science.aan8086