The four earthquakes
- December 16, 1811, 0815 UTC (2:15 a.m.); (M ~7.2 – 8.1[2]) epicenter in northeast Arkansas. It caused only slight damage to man-made structures, mainly because of the sparse population in the epicentral area. The future location ofMemphis, Tennessee experienced level IX shaking on the Mercalli intensity scale. A seismic seiche propagated upriver, and Little Prairie (a village that was on the site of the former Fort San Fernando, near the site of present-dayCaruthersville, Missouri) was heavily damaged by soil liquefaction.[3]
- December 16, 1811, 1415 UTC (8:15 a.m.); (M ~7.2–8.1) epicenter in northeast Arkansas. This shock followed the first earthquake by six hours and was similar in intensity.[2]
- January 23, 1812, 1500 UTC (9 a.m.); (M ~7.0–7.8[2]) epicenter in the Missouri Bootheel. The meizoseismal area was characterized by general ground warping, ejections, fissuring, severe landslides, and caving of stream banks. Johnson and Schweig attributed this earthquake to a rupture on the New Madrid North Fault. This may have placed strain on the Reelfoot Fault.[3]
- February 7, 1812, 0945 UTC (4:45 a.m.); (M ~7.4–8.0[2]) epicenter near New Madrid, Missouri. New Madrid was destroyed. At St. Louis, Missouri, many houses were severely damaged, and their chimneys were toppled. This shock was definitively attributed to the Reelfoot Fault by Johnston and Schweig. Uplift along a segment of this reverse faultcreated temporary waterfalls on the Mississippi at Kentucky Bend, created waves that propagated upstream, and caused the formation of Reelfoot Lake by obstructing streams in what is now Lake County, Tennessee.[3]
Susan Hough, a seismologist of the United States Geological Survey (USGS), has recently estimated the earthquakes’ magnitudes as “right around magnitude 7. Possibly a bit below, possibly a bit above, but not as big as 7.5.”[4]
Eyewitness accounts
John Bradbury, a Fellow of the Linnean Society, was on the Mississippi on the night of December 15, 1811, and describes the tremors in great detail in his Travels in the Interior of America in the Years 1809, 1810 and 1811, published in 1817.[5]
After supper, we went to sleep as usual: about ten o’clock, and in the night I was awakened by the most tremendous noise, accompanied by an agitation of the boat so violent, that it appeared in danger of upsetting … I could distinctly see the river as if agitated by a storm; and although the noise was inconceivably loud and terrific, I could distinctly hear the crash of falling trees, and the screaming of the wild fowl on the river, but found that the boat was still safe at her moorings. By the time we could get to our fire, which was on a large flag in the stern of the boat, the shock had ceased; but immediately the perpendicular banks, both above and below us, began to fall into the river in such vast masses, as to nearly sink our boat by the swell they occasioned … At day-light we had counted twenty-seven shocks.
Eliza Bryan[6] in New Madrid, Territory of Missouri, wrote the following eyewitness account in March, 1812.
On the 16th of December, 1811, about two o’clock, a.m., we were visited by a violent shock of an earthquake, accompanied by a very awful noise resembling loud but distant thunder, but more hoarse and vibrating, which was followed in a few minutes by the complete saturation of the atmosphere, with sulphurious vapor, causing total darkness. The screams of the affrighted inhabitants running to and fro, not knowing where to go, or what to do—the cries of the fowls and beasts of every species—th
e cracking of trees falling, and the roaring of the Mississippi— the current of which was retrograde for a few minutes, owing as is supposed, to an irruption in its bed— formed a scene truly horrible.
John Reynolds (February 26, 1788 – May 8, 1865) who was the 4th governor of Illinois, among other political posts, mentions the earthquake in his biography My Own Times: Embracing Also the History of My Life (1855):[7]
On the night of 16th November [sic], 1811, an earthquake occurred, that produced great consternation amongst the people. The centre of the violence was in New Madrid, Missouri, but the whole valley of the Mississippi was violently agitated. Our family all were sleeping in a log cabin, and my father leaped out of bed crying aloud “the Indians are on the house” … We laughed at the mistake of my father, but soon found out it was worse than the Indians. Not one in the family knew at the time that it was an earthquake. The next morning another shock made us acquainted with it, so we decided it was an earthquake. The cattle came running home bellowing with fear, and all animals were terribly alarmed on the occasion. Our house cracked and quivered, so we were fearful it would fall to the ground. In the American Bottom many chimneys were thrown down, and the church bell in Cahokia sounded by the agitation of the building. It is said the shock of an earthquake was felt in Kaskaskia in 1804, but I did not perceive it. The shocks continued for years in Illinois, and some have experienced it this year, 1855.
The Shaker diarist Samuel Swan McClelland described the effects of the earthquake on the Shaker settlement at West Union (Busro), Indiana, where the earthquakes contributed to the temporary abandonment of the westernmost Shaker community.[8]
Consequence of the 1811–12 earthquakes
Sand blows were common throughout the area, and can still be seen from the air in cultivated fields. The shockwaves propagated efficiently through the firm midwestern bedrock, with residents as far away as Pittsburgh, Pennsylvania, and Norfolk, Virginia, awakened by intense shaking.[9] Church bells were reported to ring as far as Boston, Massachusetts and York, Ontario (now Toronto), and sidewalks were reported to have been cracked and broken in Washington, D.C.[10] There were also reports of toppled chimneys inMaine.[citation needed]
Disaster relief
A request, dated January 13, 1812, by William Clark (famous for his exploration of the American West with Meriwether Lewis and the Corps of Discovery from 1803 to 1805), then the governor of the Louisiana Territory (the territory was renamed the Missouri Territory soon after the quake to eliminate confusion with the new state of Louisiana), asked for federal relief for the “inhabitants of New Madrid County.”
Whereas the Catalogue of miseries and afflictions, with which it has pleased the Supreme Being of the Universe to visit the inhabitants of the earth there are none more truly awful and destructive than Earthquakes … The inhabitants of the late District now County of New Madrid, in this Territory, have lately been visited with several calamities of this kind, which have deluged large portions of their country and involved in the greatest distress many families, whilst others have been entirely ruined … In the opinion of the said General Assembly provisions ought to be made by law for or cashiered to the said inhabitants relief, either out of the public fund or in some other way as may can meet to the cost demand availability of the General Government.
This is possibly the very first request that the U.S. Federal Government had received for aid from one of its territories.
Slave George murder
The earthquakes helped bring to justice the murderers of George Lewis (commonly known as “Slave George”). George was slain on the night of December 15–16, 1811 by two nephews of Thomas Jefferson, Lilburn Lewis and Isham Lewis, who were also relatives of Meriwether Lewis. After killing him with an axe in front of other slaves, George’s owners intended to burn his remains, but the first New Madrid earthquake interrupted their effort, and so the corpse was interred in a brick chimney. The murder might well have escaped discovery by authorities, except that the January 23 and February 7 quakes caused the chimney to partially collapse, exposing George’s remains. Lilburn and Isham Lewis were quickly investigated, arrested and charged. Lilburn killed himself; Isham escaped from jail and probably died during the War of 1812.[11][12]
Geologic setting