The area that is now Mississippi has a recorded earthquake history spanning more than three hundred years. The earliest documented earthquake occurred on Christmas Day 1699. Fr. J. F. Buisson St. Cosme, a French missionary, was camped along the Mississippi River below the site of Memphis when he and the rest of his party felt an earthquake. The Mississippi Territory also felt the effects of an 1811–12 series of earthquakes on deeply buried faults in the New Madrid Seismic Zone, which includes northeastern Arkansas, western Tennessee, and southeastern Missouri. Main shocks occurred on 16 December 1811, 23 January 1812, and 7 February 1812, with thousands of aftershocks. These earthquakes shook most of the United States, caused sand blows and bank sloughing in the epicentral area, and created Reelfoot Lake in northwestern Tennessee. Winthrop Sargent, first governor of the Mississippi Territory, felt the main shocks at his home near Natchez, where furniture was jarred, dishes rattled, and water sloshed in cisterns.
About one-fifth of the nearly fifty earthquakes known to have occurred in Mississippi could not be felt by humans and were detected only by instruments. The earliest earthquake with a Mississippi epicenter took place on 11 September 1853 and shook houses and alarmed inhabitants of Biloxi. The strongest earthquake in Mississippi occurred on 16 December 1931 in the Batesville-Charleston area (estimated magnitude 4.7 on the Richter scale). It was felt over sixty-five thousand square miles in northern Mississippi and parts of Alabama, Arkansas, and Tennessee. The maximum intensity of VI–VII (on the Modified Mercalli Intensity scale, which describes the effects of shaking on the ground and structures) was felt at Charleston, where walls cracked and chimneys collapsed; intensity VI damage to plaster and chimneys occurred at Belzoni, Tillatoba, and Water Valley. The second-strongest event was on 4 June 1967, when an intensity VI (magnitude 3.8) earthquake located northeast of Greenville was felt over twenty-five-thousand square miles in Mississippi, Arkansas, Louisiana, and Tennessee. The third-strongest earthquake, on 1 February 1955, was centered at Gulfport, had an intensity of V, and was felt along the Mississippi coast from Biloxi to Bay St. Louis.
Earthquakes have occurred throughout Mississippi from the northeast corner to the coast but have clustered in northwestern Mississippi, perhaps related to the New Madrid Seismic Zone or the White River Fault Zone. Several earthquakes occurred in Clarke County in the 1970s, along the Pickens-Gilbertown Fault Zone, possibly related to oil and gas activity.
An earthquake need not be located within the state to affect Mississippi. Earthquakes have occurred in all neighboring states and in the Gulf of Mexico. Various quakes have been felt in Mississippi, as have the 31 August 1886 earthquake near Charleston, South Carolina, which rocked the Vicksburg City Hall; the 31 October 1895 Charleston, Missouri, event, which was felt in most of Mississippi; the 27 March 1964 Alaska earthquake, which was detected by water-level instruments in wells in Mississippi; and the 24 March 1976 earthquake in northeastern Arkansas, which was felt across northern Mississippi.
The greatest risk to Mississippi from earthquakes is a recurrence of a strong earthquake in the New Madrid Seismic Zone. An earthquake of magnitude 7.6 (perhaps less strong than the main events of the 1811–12 series), if located at the southern end of the zone, would be felt throughout Mississippi and would cause damage in the northern part of the state. Unreinforced masonry buildings, bridges, chimneys, and other such structures would be most vulnerable. A strong earthquake in the New Madrid Seismic Zone could cause widespread destruction from Memphis to St. Louis, require a massive emergency response, and disrupt economic activity in the center of the country. Mississippi has plans for response to an earthquake disaster and could serve as a staging area for communities in more strongly affected states. Mississippi is one of eight states around the New Madrid Seismic Zone that have joined together to form the Central United States Earthquake Consortium, a Memphis-based organization that includes emergency management directors as well as state geologists and transportation officials.
- Michael B. E. Bograd, Earthquakes in Mississippi, Mississippi Office of Geology, Fact Sheet 1 (June 2008)
- B. C. Moneymaker, Journal of the Tennessee Academy of Science (July 1954).
- Winthrop Sargent, Memoirs of the American Academy of Arts and Sciences (1814).