A recent study conducted by scientists at the University of South California (USC) and published in the journal Nature Geoscience has revealed changes in the internal structure of the Earth’s nucleus. While previous studies predominantly focused on the rotation of the nucleus, new data suggests that its surface may also undergo changes in shape.
Traditionally, the inner core of the Earth, located approximately 3,000 miles below the surface, was thought to be a solid sphere. However, recent analysis of seismic wave data collected over the past few decades has uncovered signs of deformation within the inner core. Lead author of the study, John Vidale, expressed surprise at the unexpected discovery of structural changes within the nucleus.
The research utilized seismic data gathered between 1991 and 2024, including information on 121 repeating earthquakes in the Southern Sandwich Islands region. Analysis of seismograms from Alaska and Canada revealed abnormal wave signals not previously observed. Scientists suggest that these signals may be attributed to changes in the shape of the inner nucleus resulting from interactions with the liquid outer core.
Previously, the outer core was viewed as a turbulent molten layer with a consistent influence on the inner core. However, the study indicates that movements within the outer core can now cause deformation of the inner nucleus over relatively short time periods. This groundbreaking discovery may alter current understanding of the Earth’s deep processes and contribute to a better comprehension of the factors impacting the geomagnetic field and thermal evolution of the planet.