Where and when were the largest earthquakes in the USA?
The ten largest earthquakes in the United States
| # | Magnitude | Date (UTC) | Location |
|---|---|---|---|
| 1. | 9.2 | March 28, 1964 | Prince William Sound, Alaska |
| 2. | 8.8 | March 9, 1957 | Andreanof Islands, Alaska |
| 3. | 8.7 | February 4, 1965 | Rat Islands, Alaska |
| 4. | 8.3 | November 10, 1938 | East of Shumagin Islands, Alaska |
| 8.3 | July 10, 1958 | Lituya Bay, Alaska | |
| 6. | 8.2 | September 10, 1899 | Yakutat Bay, Alaska |
| 8.2 | September 4, 1899 | near Cape Yakataga, Alaska | |
| 8. | 8.0 | May 7, 1986 | Andreanof Islands, Alaska |
| 9. | 7.9 | February 7, 1812 | New Madrid, Missouri |
| 7.9 | January 9, 1857 | Fort Tejon, California | |
| 7.9 | April 3, 1868 | Ka'u District, Island of Hawaii | |
| 7.9 | October 9, 1900 | Kodiak Island, Alaska | |
| 7.9 | November 30, 1987 | Gulf of Alaska |
The ten largest earthquakes in the Contiguous United States
| # | Magnitude | Date (UTC) | Location |
|---|---|---|---|
| 1. | 7.9 | February 7, 1812 | New Madrid, Missouri |
| 7.9 | January 9, 1857 | Fort Tejon, California | |
| 3. | 7.8 | March 26, 1872 | Owens Valley, California |
| 7.8 | February 24, 1892 | Imperial Valley, California | |
| 5. | 7.7 | December 16, 1811(0815) | New Madrid, Missouri area |
| 7.7 | April 18, 1906 | San Francisco, California | |
| 7.7 | October 3, 1915 | Pleasant Valley, Nevada | |
| 8. | 7.6 | January 23, 1812 | New Madrid, Missouri |
| 9. | 7.5 | July 21, 1952 | Kern County, California |
| 10. | 7.3 | November 4, 1927 | West of Lompoc, California |
| 7.3 | December 16, 1954 | Dixie Valley, Nevada | |
| 7.3 | August 18, 1959 | Hebgen Lake, Montana | |
| 7.3 | October 28, 1983 | Borah Peak, Idaho |
Note: Widely differing magnitudes have been computed for some of these earthquakes; the values differ according to the methods and data used. For example, some sources list the magnitude of the 8.7 Rat Islands earthquake as low as 7.7. On the other hand, some sources list the magnitude of the February 7, 1812 New Madrid quake as high as 8.8.
Similar variations exist for most events on this list, although generally not so large as for the examples given. In general, the magnitudes given in the list above have been determined from the seismic moment, when available. For very large earthquakes, the moment magnitude is considered to be a more accurate determination than the traditional amplitude magnitude computation procedures. Note that all of these values can be called "magnitudes on the Richter scale," regardless of the method used to compute them.
Source:
- C.W. Sptover and J.L. Coffman, Seismicity of the United States, 1568-1989 (Revised), U.S. Geological Survey Prof. Paper 1527, 1993.
URL: http://eqinfo.ucsd.edu/faq/big_eqs.php [Last updated: 2009-10-16 (289) 22:51:37 UTC]
