Valdivia earthquake and Earth's free oscillations
Terremoto de Valdivia y oscilaciones libres de la Tierra
- Date
- 1960-1961 · confidence high
- Place
- Valdivia, Los Ríos, Chile
- Credited to
- Hugo Benioff, Frank Press, Stewart Smith; Ness, Harrison and Slichter
- Field
- Cosmos & Earth
What was discovered
The Mw 9.5 earthquake of 22 May 1960 is the largest ever recorded by instruments. It allowed the first observation, mainly with seismographs and gravimeters, of the Earth's free oscillations, the planet 'ringing' for days.
Free oscillations had been predicted in the 19th century; the first records are credited to Caltech and UCLA teams in 1960-1961.
What it led to
- Normal-mode seismology and the Earth's interior structure
- Verification of plate tectonics theory at subduction zones
- Tsunami warning networks