Deep-Earth Phase Shift Behind Mysterious Gravity Glitches
NASA/DLR GRACE data showed a deep mantle gravity anomaly from 2006–2008 stretching across the eastern Atlantic. Scientists traced the signal to a phase transition in bridgmanite near the core–mantle boundary, where mineral structure changes redistribute mass and alter density. This deep-seated gravitational anomaly, not fully explained by surface water, helps explain previous geomagnetic-field–related gravity fluctuations and will guide models of core–mantle dynamics and mantle convection.
