Forces deep underground seem to be deforming Earth's inner core
New ScientistFEB 8
Scientists at the University of Southern California have discovered that Earth's inner core — previously considered a solid sphere — is changing shape at its edges, with deformations of up to one kilometer occurring within just a few years.
The research team, led by John Vidale, analyzed 168 pairs of earthquake waves from 42 locations near Antarctica's South Sandwich Islands between 1991 and 2023, comparing seismic data received at stations in Alaska and Canada to detect these structural changes.
Located approximately 3.2K miles deep, the inner core reaches temperatures of 5.2K°C and consists primarily of solid iron and nickel. It's surrounded by a liquid outer core that plays a crucial role in generating Earth's magnetic field.
The discovery of inner core deformation represents a groundbreaking advancement in understanding Earth's internal dynamics. The changes suggest a more dynamic and interconnected relationship between the inner and outer core than previously thought, potentially affecting the planet's magnetic field generation and rotation patterns.
The observed changes might have alternative explanations beyond shape deformation, such as unrelated changes in the outer core or convection within the inner core itself. The limited data coverage and indirect nature of seismic measurements make it challenging to definitively determine the exact nature of these changes.