As earthquakes continue to occur on a daily basis in the central U.S., CUSEC and emergency management officials in Arkansas, Illinois, and Missouri remind citizens and communities about the earthquake risk by designating February as Earthquake Awareness Month. February 7 is the anniversary of the last of the earthquakes that struck the central U.S. in the winter of 1811-12. According to the US Geological Survey:
This sequence of three very large earthquakes is usually referred to as the New Madrid earthquakes, after the Missouri town that was the largest settlement on the Mississippi River between St. Louis, Missouri and Natchez, Mississippi. On the basis of the large area of damage (600,000 square kilometers), the widespread area of perceptibility (5,000,000 square kilometers), and the complex physiographic changes that occurred, the New Madrid earthquakes of 1811-1812 rank as some of the largest in the United States since its settlement by Europeans.
While scientists say that there is a 7-10% probability of a re-occurrence of the 1811-12 earthquakes within any 50-year window, they also estimate that there is a 25-40% probability of a M6.0 or greater earthquake occurring in the central U.S. within the same period of time. About 200 earthquakes occur in the central U.S. every year-many of which go unnoticed. And while the primary focus remains on the NMSZ, it is not our only area of concern. Earthquakes are also occurring along the Wabash Valley and East Tennessee Seismic Zones and in Oklahoma, Kansas, Ohio, and Texas.