Register · Events
A timeline of major earthquakes at magnitude 8.6 and above
The U.S. Geological Survey’s historical list places the 1960 Valdivia earthquake at magnitude 9.5. The register follows earthquakes of magnitude 8.6 or above in that list and includes the separately catalogued 2025 Kamchatka earthquake.
Sources checked
- 31 January 1906Off Ecuador and Colombia, magnitude 8.8
- 22 May 1960Valdivia, Chile, magnitude 9.5
- 28 March 1964Prince William Sound, Alaska, magnitude 9.2
- 26 December 2004Sumatra-Andaman Islands, magnitude 9.1
- 11 March 2011Tohoku, Japan, magnitude 9.1
- 29 July 2025Kamchatka Peninsula, Russia, magnitude 8.8
Markers are in chronological order. Spacing between markers does not represent elapsed time.
Valdivia and Alaska lead the historical list
USGS places the 22 May 1960 earthquake in Chile at magnitude 9.5 and the 28 March 1964 event in southern Alaska at 9.2. The chart arranges selected events by date. The register includes 13 earthquakes at 8.6 or above from the historical list, plus the 2025 Kamchatka event. Source 1 Source 3
Small gaps in magnitude represent large changes in energy
The USGS guide describes the scale as logarithmic. Using its approximate energy formula, an increase of 0.4 magnitude units, the difference between 9.1 and 9.5, corresponds to roughly four times the energy released. Local shaking also depends on where the observer was relative to the earthquake. Source 1 Source 2
Two 9.1 events have distinct records
USGS gives the 26 December 2004 Sumatra-Andaman earthquake and the 11 March 2011 Tohoku earthquake the same magnitude to one decimal place. Their coordinates and dates identify different events. The register also keeps the 2005 Nias and 2012 offshore Sumatra earthquakes distinct by date and coordinates. Source 1
The local day can differ from UTC
The 2025 Kamchatka earthquake was recorded late on 29 July in UTC and occurred on 30 July in local time. Use the UTC timestamp and the epicentre when matching dates to the official record. The data table follows USGS timestamps and shows them to the minute. Source 1 Source 3