Most Destructive Earthquakes

The following list identifies the most destructive known earthquakes in the world on record in terms of loss of human life (50,000 or more) in order of the greatest number of deaths.[1] Note that the earthquakes with the greatest number of deaths and the lowest magnitude were in Haiti and China. The deaths were largely due to shoddy construction techniques and not the severity of the earthquake. Also note the huge range in deaths listed for the 1976 Tangshan earthquake. That range is not the result of poor reporting but rather the reluctance of the Chinese government to suffer public humiliation over the actual enormous loss of lives. Thus, the first number in the range is that reported officially by the government and the larger number is an estimate from more objective sources.

Date                                Location                             Deaths                        Magnitude

January 1556                    Shansi, China                      830,000?                             NA

January 12, 2010              Port-au-Prince                     316,000                               7.0

July 27, 1976                   Tangshan, China                 243,000-650,000                   7.5

December 26, 2004          Sumatra, Indonesia            300,000+                               9.2

October 1737                   Calcutta, India                     300,000                                NA

July 27, 1976                   Tangshan, China                 255,000+                             8.0

August 1138                    Aleppo, Syria                      230,000                                NA

May 22, 1927                   Xining, China                       200,000                               8.3

December 856+               Damghan, Iran                     200,000                                NA

December 1920               Gansu, China                      200,000                               8.6

March 893+                    Ardabil, Iran                         150,000                                NA

September 1923             Kwanto, Japan                    143,000                                 8.3

October 5, 1948              USSR                                   110,000                                7.3

September 1290             Chihli, China,                       100,000                                NA

October 2005                 Pakistan/Kashmir                 88,000+                               7.6

November 1667              Shemakha, USSR                80,000                                NA

November 1727              Tabriz, Iran                             77,000                                NA

December 1908              Messina, Italy                         70,000                                7.5

November 1755               Lisbon, Portugal                    70,000                                8.7

December 1932              Gansu, China                        70,000                                7.6

May 12, 2008                 Sichuan, China                      69,000+                              7.9

May 31, 1970                 Peru                                        66,000                               7.8

Month N/A 1268             Silicia, Turkey                        60,000                                NA

January 1693                 Italy, Sicily                              60,000                                NA

February 1783               Calabria, Italy                        50,000                                NA

June 20, 1990                Iran                                          50,000                             7.7

May 30, 1935                 Quetta, Pakistan                   30,000/60,000                     7.5

Real World Examples: On May 22, 1960, at 19:11 GMT, an earthquake occurred off the coast of South Central Chile that triggered a Pacific-wide tsunami with an epicenter of 39.5° S, 74.5° W and a focal depth of 33 kilometers. The number of fatalities associated with both the tsunami and the earthquake has been estimated to range from 490 to almost 2,300. What happened as a result of the earthquake (with a Richter magnitude of 9.6) was that a piece of the Pacific sea-floor near the coast of Peru, or strictly speaking part of the Nazca Plate that was about the size of California, dropped fifty feet. Like a spring, the lower slopes of the South American continent offshore snapped upwards as much as twenty feet while land along the Chile coast dropped about ten feet. This sudden deformation of the ocean bottom changed the shape of the sea surface. Since the sea surface likes to be flat, the pile of excess water at the surface collapsed and combined with the earthquake energy waves to create a series of waves that became the tsunami.

That seismic sea wave, together with the subsequent coastal subsidence and flooding, caused large-scale and widespread damage along the Chilean coast, killing about 2,000 people. As the waves spread outwards across the Pacific about 15 hours later they struck Hilo, Hawaii, where they built up to a height of thirty feet along the coast and caused 61 deaths along the waterfront. Seven hours later (22 hours after the earthquake) the tsunami hit the coastline of Japan, where ten-foot high waves caused 200 deaths. The waves also caused damage in the Marquesas, Samoa, and New Zealand. Tide gauges throughout the Pacific region measured anomalous oscillations for about three days as the waves oscillated from one side of the Ocean basin to the other.

The great Alaskan earthquake of 1964 was the largest earthquake in North America and the second largest ever recorded (largest occurred in Chile in 1960 as discussed above). The earthquake occurred at 5:36 pm on March 27, 1964, Alaska Standard Time. The epicenter was located in the Northern Prince William Sound about 75 miles east of Anchorage, or about 55 miles west of Valdez. The reported Richter magnitudes for that event ranged from 8.4 to 8.6. The moment magnitude (Mw) was reported as 9.2. The depth, or point where the rupture began, was about 14 miles within the Earth’s crust. The resulting seismic sea waves killed 110 people. Vertical displacement of the land surface caused by the earthquake affected an area of about 200,000 square miles and ranged from about 35 feet of uplift to seven feet of subsidence relative to sea level. The greatest absolute vertical displacement occurred at the southwest end of Montague Island, ranging from about 40 to 46 feet.

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[1] Source: U.S. Geological Survey National Earthquake Information Center. http://neic.usgs.gov/ and http://earthquake.usgs.gov/earthquakes/world/most_destructive.php