In the Media

Researchers from MIT and elsewhere have found that a sequence of rocks from the Isua Supracrustal Belt in Greenland contain “an ironclad record of the early Earth’s magnetic field,” reports Keith Cooper for Space.com. “The new results from the Greenland rocks are considered more reliable because, for the first time, they are based on entire iron-bearing rocks (rather than individual mineral crystals) to derive the primordial field strength,” explains Cooper. “Therefore, the sample offers the first solid measure of not only the strength of Earth's ancient magnetic field, but also of the timing of when the magnetic field originally appeared.”