Memphis was not available for European settlement until after 1812, and an agreement with the Chickasaw Indians. Memphis was built on/near the "fourth Chickasaw bluffs (just north of town). Fuller's book, made from horseback observation 100 years ago, is regarded as authoritative. Fuller talks about the environmental impact of the quakes.

Map and info below come from book "On Shaky Ground: The New Madrid Earthquakes of 1811-1812" By Norma Hayes Bagnall 1996. Map originally from State of Missouri Handbook 1945-1946.

Lewis & Clark found the Shawnee village north of Cape Girardeau in 1803 and said it numbered 400 inhabitants. Area is now northern Cape Girardeau County.

http://www.amnh.org/nationalcenter/youngnaturalistawards/1999/hagenauer.html

The older Richter scale measurements saturate at higher levels. Many scientists now consider these quakes high 7's. This map came from Close environmental. Likely from David Stewart.

The New Madrid Fault is well below the surface and none of it is visible. This is how some of it might appear. Many quakes are 5-10 miles underground, but some are more than 100.

California faults are nearer the surface. This photo shows a section of the San Andreas fault alongside a road in Palmdale, California, an hour north of Los Angeles. Compare this picture to the quake diagrams, models of one section being forced underneath another.

Benton Hills, Bloomfield Hills, Western Lowlands, Eastern Lowlands, Sikeston Ridge, Oran-Bell City Gap

In Fig. 1.4 the Mississippi River, during the first part of the age of glaciers, flowed from the top inlet of the map (Cape Girardeau), to the "western lowlands" near Poplar Bluff, before spilling out across the bootheel and eastern Arkansas. Then a gap developed between the Benton Hills and Bloomfield Hills (Crowley's Ridge), allowing the river to flow through the "eastern lowlands" -- the Oran - Bell City gap, just west of Sikeston Ridge.
Until 10,000 years ago the Ohio flowed a bit north of its current route across Southern Illinois, then along the south side of the Benton Hills. See topography- The Thebes gap of the Mississippi River is relatively young, about 10,000 years old, probably helped by earthquakes along the Commerce Lineament.

Commerce Lineament Map (below)

The illustration shows how the Mississippi River has meandered over the centuries. This is a Corps of Engineers map from about 1944, from Cape Girardeau Mo to Donaldsonville, La. It makes nice artwork.

A map of Mercalli scale intensities.

Clicking a map will usually take you to its source.

Point Pleasant

At 8 a.m. January 23, 1812, another big shake struck, north of Caruthersville. The town of Point Pleasant, southeast of Marston, on a point of land sticking into the Mississippi River, completely crashed into the river and was swept away without a trace. The townspeople had all fled, a month earlier, because of the tremors. The town was rebuilt, perhaps a mile west of the original location. The white line on Google Earth map above shows one mile. The levee makes a slight detour to include the new town, and 30-40 people who currently live there. The white area just upriver on Google Earth map is current site of power and aluminum plants.

Point Pleasant had some Civil War involvement, but the main Civil War activity was just to the right of Google map. The Rebs had 30 guns on Island 10 at bottom of river loop. The Yanks had several iron-sided gunboats waiting just upriver for three weeks. The Yanks dug a shallow canal that came out just east of New Madrid, to bypass Island 10 and move supplies. They got the canal finished about the same time they decided to sneak one, then another gunboat past island 10.  more

City above marked Caruthersville, should be Sikeston. Caruthersville is near Tiptonville.  The hatched regions are plutons.  Thick lines denote the boundary of the Reelfoot rift.  Thinner northwest trending lines denote the approximate lateral extent of the Missouri batholith.  Triangles are seismic stations.

above shows connection of Wabash Fault and New Madrid Faults.