Magnetic ringing of the Earth
DOI: 10.1063/PT.5.023409
Nature : Large earthquakes excite wave motion throughout the Earth, causing it to ring like a bell. The resulting ground motion, measured by seismometers, provides helpful constraints on Earth’s internal structure through the study of its “normal modes"—free oscillations that occur at discrete frequencies.
Seismologically measurable oscillations have typical periods of a few minutes. But in work just published in Geophysical Journal International , Bruce A. Buffett, Jon Mound, and Andrew Jackson sound the Earth, in particular its core, through oscillations that have periods of decades.
Related Link Inversion of torsional oscillations for the structure and dynamics of Earth’s core
