How was Earth’s early magnetic field produced? New experimental results and modeling show that the energy source could not have come from exsolution of lithophile elements from the core.
Earth’s core
![Figure 2 from Wang and Tkalčić [2021]](https://i0.wp.com/eos.org/wp-content/uploads/2022/01/2021GL094784-Figure-2-sized-1200x675-1.png?resize=1200%2C675&ssl=1)
Posted inEditors' Highlights
Observation of Shear Wave Anisotropy in the Earth’s Inner Core
Coda-correlation wavefields reveal direction-dependent inner-core shear-wave speed, ~5 s faster in directions oblique to the Earth’s rotation axis than directions parallel to the equatorial plane.
Posted inNews
Can NASA’s Gravity Satellites Detect Motions in Earth’s Core?
Measurements of our planet’s gravitational field could expose processes in the fluid outer core—if scientists can decipher the signals.
Posted inResearch Spotlights
Long-Term Sea Level Cycle Affects Predictions of Future Rise
New research confirms the existence of a regular, long-term fluctuation in sea level, perhaps caused by processes in Earth’s core.
Posted inNews
How Geodynamo Models Churn the Outer Core
New simulations of Earth’s outer core have reproduced magnetic fields that—for the first time—match paleomagnetic data collected from rocks.
Posted inNews
A Robust Proxy for Geomagnetic Reversal Rates in Deep Time
The strength of Earth’s magnetic field in the distant past can tell scientists whether the planet’s magnetic poles were steady or prone to frequent reversals.
Posted inFeatures
Earth’s Core Is in the Hot Seat
How old is Earth’s inner core? High-pressure and high-temperature experiments suggest that our planet’s inner furnace may be much younger than expected.
Posted inEditors' Highlights
Earthquake-coda Tomography Boosts Illumination of the Deep Earth
A new tomographic method based on correlations of seemingly chaotic earthquake coda waves yields otherwise unobservable arrivals, thus greatly improving illumination of the deep Earth.
Posted inEditors' Highlights
Thermal Convection Can Power the Geodynamo
New high-pressure experiments on fluid iron suggest thermal convection without compositional buoyancy is sufficient to drive the dynamo generating Earth’s magnetic field.