The Earthquakes of 1811 and 1812 in the Mississippi River Valley

The Earthquakes of 1811 and 1812 in the Mississippi River Valley When one thinks of earthquakes, the Mississippi river valley (MRV), does notfrequently come to mind. One usually thinks of one of California's numerous faults orsomewhere in Alaska. However, little known to the general public, there were twomassive earthquakes in the MRV, which rank among the top three in the contiguousUnited States and in the top ten for the entire United States (http://wwwneic.cr.usgs.gov/neis/eqlists/bigten.lis). Starting in the early morning hours of December 16,1811 a violent shaking of the earth began, which continued on for three months,producing two of the three largest quakes in the contiguous US, this particular quakeregistered an 8.0 in magnitude on the Richter scale. There was a second quake onFebruary 7, 1812 which registered 8.2 (http://wwwneic.cr.usgs.gov/neis/eqlists/bigten.lis).The plate which is responsible for this activity is named the New Madrid Seismiczone, it is named for the only populated city that was in existence in the time and the areaof these earthquakes, New Madrid, Missouri.Mississippi HoneyThe New Madrid Seismic zone lies in thecentral MRV, starting in southern Illinois and ending in southeast Missouri, westernTennessee.Usually an earthquake consists of a principal shock and then the aftershocks, the1811-1812 earthquakes didn't follow the usual pattern. There was the first primary shock,at and then it's aftershocks, however the aftershocks from the first quake hadn't subsidedbefore the second principal shock hit. Following suite, the aftershocks from the secondquake had not terminated when the third and largest principal shock hit (eas.slu.edu/Earthquake_Center/Nuttli.1973/intensity.html). It is difficult to gage the actualintensity of the earthquakes due to the lack of technology, however, the strength can beestimated by the damage caused by the quakes and also by the journals of the peoplesettling this part of the country. Fortunately, a...