In an attempt to obtain as complete a set of information as practical, and to avoid possible errors resulting from using secondary or tertiary sources, the present author has gone back to the original newspaper accounts wherever possible. The papers consulted were the Louisiana Gazette of St. Louis (later called the Missouri Gazette), the Louisiana Gazette and Daily Advertiser of New Orleans, the Pittsburgh Gazette, the Pennsylvania Gazette of Philadelphia, the New York Evening Post, the York Gazette of York, Upper Canada (now Toronto), the Quebec Mercury and the Montreal Herald. With the exception of the Louisiana Gazette and Daily Advertiser, the author looked at all issues from December 16, 1811 through June, 1812 and copied everything in them pertaining to the earthquakes. Although aftershocks were felt at least through 1813, they apparently were not considered newsworthy, especially when compared with such events as the War of 1812 and Napoleon's adventures in Europe.
The microfiche card, APPENDIX - NEWSPAPER ACCOUNTS (132kB no image) which can be found in the jacket attached to the back page of this issue, contains a retyped copy of the newspaper accounts of the earthquakes. The only materials pertaining to the earthquakes that were omitted are the accounts that were exact duplicates of an article ftom one of the other papers and a series of letters by one particular individual that later was refuted and proved to be a hoax. The material is arranged according to newspaper, the order being the same as that given above. For any given newspaper the arrangement is chronological, as it appeared in the paper. When no city or town is identified with a particular report, it indicates that the report pertains to the city in which the paper was published.
The earthquake activity began with a major shock on December 16, 1811 at about 2h15m local time (8h15m GMT). Table I summarizes the intensity data for this earthquake, the intensity values being those assigned by the present author. Although there is a certain degree of subjectivity in assessing intensities from such sources of information, in most cases the uncertainty probably does not exceed +/- 1 intensity unit.
|Locality||MM Intensity||Source of Information|
|Below St. Francis River, Ark.||X-XI||Pitt. Gaz., Feb. 14, 1812|
| Little Prairie, Mo.
|X-XI||Pitt. Gaz., Jan. 31 and Feb. 14,1812;
History of Southeast Missouri (1888, p. 306)
|White River, Ark.||X||La Gaz., Feb. 15 and 22,1812|
Islands 30 to 40
|X||Pitt. Gaz., Mar. 13, 1812|
|Northeastern Ark.||IX||Fuller (1912, p. 21)|
|Fort Pickering, Tenn.
|IX||N.Y. Post, Feb. 11, 1812|
|New Madrid, Mo.||IX|| Penn. Gaz., Feb. 12, 1812;
History of Southeast Missouri (1888, p. 304)
|Cape Girardeau, Mo.||VIII-IX||La Gaz., Dec. 28, 1811|
|St. Louis, Mo.||VII-VIII||La Gaz., Dec. 21, 1811|
|Henderson City, Ky.||VII-VIII||Mitchill (1815, p. 290)|
|Nashville, Tenn.||VII-VIII||La. Gaz., Dec. 28, 1811|
|Piney River, Tenn.||VII-VIII||Penn. Gaz., Feb. 5, 1812|
|Vicksburg, Miss.||VII||Fuller (1912, p. 43)|
|Lexington, Ky.||VII||N.Y. Post, Feb. 11, 1812|
|Louisville, Ky.||VII||Mitchill (1815, p. 287)|
|Carthage, Tenn.||VII||Mitchill (1815, p. 292)|
|Red Banks, Tenn.||VII||Mitchill (1815, p. 288)|
|Herculaneum, Mo.||VI-VII||Mitchill (1815, p. 290)|
|Vincennes, Ind.||VI-VII||Mitchill (1815, p. 288)|
|Cincinnati, Ohio||VI-VII||Fuller (1912, p. 19)|
|Natchez, Miss.||VI||La. Gaz. and Dly. Adv., Dec. 31, 1811|
|Columbia, Tenn.||VI||Mitchill (1815, p. 287)|
|Circleville, Ohio||VI||Mitchill (1815, p. 289)|
|Lebanon, Ohio||VI||Mitchill (1815, p. 289)|
|Arkport, N.Y.||VI||Penn. Gaz., Jan. 29, 1812|
|Washington, La.||V-VI||La. Gaz. and Dly. Adv., Dec. 31, 1811|
|Knoxville, Tenn.||V-VI||Mitchill (1815, p. 287)|
|Charleston, S.C.||V-VI|| Penn. Gaz., Jan. 1, 1812;
La. Gaz., Feb. 22, 1812
|Columbia, S.C.||V-VI||Mitchill (1815, p. 28)|
|Ft. St. Stephens, La.||V||Pitt. Gaz., Feb. 7, 1812|
|Meadville, Pa.||V||Pitt. Gaz., Dec. 20, 1811|
|Pittsburgh, Pa.||V||Pitt. Gaz., Dec. 20, 1811|
|Waterford, Pa.||V||Pitt. Gaz., Dec. 20, 1811|
|Georgetown, S.C.||V||N.Y. Post, Dec. 26, 1811|
|Norfolk, Va.||V||Penn. Gaz., Dec. 25, 1811|
|Richmond, Va.||V|| Penn. Gaz., Dec. 25, 1811;
N.Y. Post, Dec. 23, 1811
|Ft. Stoddert, La.||IV-V||La. Gaz., Feb. 29, 1812|
|Washington, D.C.||IV-V||Mitchill (1815, p. 282)|
|Savannah, Ga.||III-IV||La. Gaz., Feb. 22, 1812|
|Raleigh, N.C.||III-IV||N.Y. Post, Dec. 18, 1811|
|New Orleans, La.||III||Fuller (1912, p. 21)|
|Charlestown, N.H.||II-III||La. Gaz., Mar. 14,1812|
Figure 1 is a generalized isoseismal map of the earthquake. Because the region to the west of the epicenter was so sparsely inhabited, no satisfactory intensity data are available for that area. A striking feature of the map is the extent of the area which experienced damaging earth motions (intensity >/= VII). Assuming, conservatively, that the radius of curvature of the isoseismal lines is the same to the west as to the south, there was an area of potential damage of 600,000 square km, i.e., an area with intensity of VII or greater.
By similar reasoning, ground motions large enough to alarm the general population (intensity >/= V) occurred over an area of 2,500,000 square km. Except for later shocks of the 1811-1812 sequence, no earthquakes in the recorded history of the United States have had a damage or felt area anywhere approaching this size. For example, the 1906 San Francisco earthquake had an area with intensity >/= VII of about 30,000 square km, and with intensity >/= V of about 150,000 square km (Lawson, 1908). On a global scale, the only other seismic region which is notable for such anomalously large damage and felt areas is the subcontinent of India. For example, the three great Indian earthquakes of June 16, 1819, June 12, 1897 and January 15, 1934 had comparable damage and felt areas (Richter, 1958; Davison, 1936).
Although the 1811-1812 earthquakes often are called the New Madrid earthquakes or earthquake, there is sufficient evidence to place the epicenter of the first earthquake (December 16, 1811 at 08h15m GMT) to the southwest, probably in northeast Arkansas near the southern end of the lake formed by the St. Francis River (Figure 2). One lake in that vicinity was raised up higher than the surrounding country. The water in the lake drained through fissures in its bottom and was replaced by a white sand, which was covered by numerous dead fish. Nearby, water rose from the Earth to waist depth. In addition to the region of uplift, there was subsidence by as much as 12 ft at other localities in the area (Pittsburgh Gazette, February 14, 1812). Along the Mississippi River, the greatest disturbance occurred some distance to the south of New Madrid (Pittsburgh Gazette, March 13, 1812), between Islands 30 and 40 (see Figure 2). The earth motions were violent on the headwaters of the White River, where a Mr. Carrin was drowned.
|Locality||MM Intensity||Source of Information|
|New Madrid, Mo.||IX|| History of Southeast Missouri
(1888, p. 304)
|Cape Girardeau, Mo.||VIII||La. Gaz., Feb. 29, 1812|
|Charleston, S.C.||VI||N.Y. Post, Jan. 31, 1812|
|Richmond, Va.||V||N.Y. Post, Feb. 5, 1812|
|New Orleans, La.||IV-V||La. Gaz. and Dly. Adv., Jan. 24, 1812|
|Jamaica, L.I., N.Y.||IV||Penn. Gaz., Jan. 29, 1812|
|Annapolis, Md.||IV||Penn. Gaz., Jan. 29, 1812|
|Easton, Md.||IV||Penn. Gaz., Jan. 29, 1812|
|Ft. Wm. Henry, N.Y.||IV||Montreal Her., Feb. 1, 1812|
|York (Toronto), Canada||IV||York Gaz., Jan. 24, 1812|
|Alexandra, Va.||III-IV||Penn. Gaz., Jan. 29, 1812|
|Baltimore, Md.||III||Penn. Gaz., Jan. 29, 1812|
|Raleigh, N.C.||II||Penn. Gaz., Feb. 5, 1812|
|Locality||MM Intensity||Source of Information|
|New Madrid, Mo.||X-XI||Penn. Gaz., Mar. 18, 1812|
|Cape Girardeau, Mo.||IX||La. Gaz., Feb. 29, 1812|
|Cahokia, Ill.||IX||McDermott (1949, p. 317)|
|St. Louis, Mo.||VIII-IX||La. Gaz., Feb. 8, 1812|
|Savannah, Ga.||IV-VI||N.Y. Post, Mar. 5,1812|
|Richmond, Va.||V-VI||N.Y. Post, Feb. 18, 1812|
|Pittsburgh, Pa.||V-VI||Pitt. Gaz., Feb. 14, 1812|
|New Orleans, La.||V||N.Y. Post, Mar. 5, 1812|
|Augusta, Ga.||V||N.Y. Post, Mar. 5, 1812|
|Washington, D.C.||V||N.Y. Post, Feb. 11, 1812|
|Alexandria, Va.||IV-V||N.Y. Post, Feb. 12, 1812|
|Baltimore, Md.||IV-V||Penn. Gaz., Feb. 12, 1812|
|New York, N.Y.||IV-V||Penn. Gaz., Feb. 12, 1812|
Coal and sand were thrown from fissures in the swampland adjacent to the St. Francis River, and the water level is stated to have risen there by 25 to 30 ft (Louisiana Gazette, February 22, 1812). At New Madrid itself, although the motion was violent, it was not so severe and destructive as that caused by the smaller magnitude aftershocks which followed about 4 and 5 hr later (Pennsylvania Gazette, February 12, 1812), indicating that the epicenters of the latter were closer to New Madrid. Fuller (1912), quoting "various authorities", stated that for the December 16 earthquake the direction from which the vibrations were reported as coming was the southwest. He believed that the epicenter of this earthquake, as well as the other two principal ones which occurred on January 23 and February 7, 1812, lay along a northeast-southwest trending fault about 25 km west of the Mississippi River at New Madrid. Mateker (1968) gives indication of a major surface and a subsurface fault which would correspond to that proposed by Fuller.
One of the unusual features of the 1811-1812 sequence was that it did not consist of a principal shock and its aftershocks, but rather of three principal shocks, each with its own rather anomalous aftershock series. Undoubtedly, there was temporal overlapping of the aftershock sequences, i.e., the aftershock activity of the December 16, 1811 earthquake at 08h15m GMT had not terminated when the second principal shock occurred on January 23, 1812 at 15h00m GMT, and the aftershock series of both of these earthquakes were not completed when the third, and largest, principal shock occurred on February 12, 1812 at 09h45m GMT. These origin times should be considered reliable only to the nearest 15 min, because of the uncertainties in timekeeping.
It is difficult to assign intensities to the later principal shocks, because many of the published accounts describe the cumulative effects of all of the earthquakes. Tables 2 and 3 present the limited information that could be uncovered. There is insufficient information to construct isoseismal maps, such as that for the earthquake of December 16. In all accounts, the February 7, 1812 earthquake was described as being the most severe. Cracks developed in brick buildings in Savannah, Georgia (New York Evening Post, March 5, 1812). A chimney top was thrown down in Richmond, Virginia (New York Evening Post, February 18, 1812). Many houses were badly damaged and their chimneys thrown down in St. Louis (Louisiana Gazette, February 8, 1812). The town of New Madrid was completely destroyed. Whereas, formerly it was 25 ft above river level, it was only 12 ft above after the earthquake. Near it the river overflowed its banks, and the land was covered with sand blows 12 to 50 ft in diameter (Pennsylvania Gazette, March 18, 1812). From these and other similar accounts, it seems that the epicenter of the February 7 earthquake was close to New Madrid.