Young inner core inferred from Ediacaran ultra-low geomagnetic field intensity

@article{Bono2019YoungIC,
  title={Young inner core inferred from Ediacaran ultra-low geomagnetic field intensity},
  author={Richard K. Bono and John A. Tarduno and Francis Nimmo and Rory D. Cottrell},
  journal={Nature Geoscience},
  year={2019},
  volume={12},
  pages={143-147}
}
An enduring mystery about Earth has been the age of its solid inner core. Plausible yet contrasting core thermal conductivity values lead to inner core growth initiation ages that span 2 billion years, from ~0.5 to >2.5 billion years ago. Palaeomagnetic data provide a direct probe of past core conditions, but heretofore field strength data were lacking for the youngest predicted inner core onset ages. Here we present palaeointensity data from the Ediacaran (~565 million years old) Sept-Îles… 

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