Ready for the next BIG ONE?

One of the most prominent features on the U.S. Geological Survey (USGS) Seismic Hazard map is the red high hazard zone surrounding the New Madrid Seismic Zone; as high as other western areas famous for quake activity. The zone is active, averaging more than 200 measured seismic events per year…

Unlike the West Coast where major quake activity is more predictable based on measured movement at tectonic plate boundaries, New Madrid is located near the center of the North American Plate. The crust in the central U.S. is being deformed / strained slowly in contrast to conditions in the west. What has been learned in studies there may not apply here.

Another contrast is due to a difference in geological characteristics. The harder, colder, drier, less fractured crust in the central U.S generates greater shaking over larger areas than quakes of comparable magnitude in the west. Shake and damage areas are up to 20 times larger than similar West Coast quakes…

To date, the earthquakes of 1811-1812 remain 1 of the most remarkable seismic events in history. On the USGS list of the 20 largest earthquakes in all 50 United States, the 3 main shocks are ranked #18, 19, and 20 (Alaska dominates the top of the list). On the list for the continental 48 states, the New Madrid main shocks are ranked #5, 6, and 7…

In the 200 years since 1811, changes to the areas that would be affected by major quake activity in the zone have been drastic. Sparsely populated and developed then, there were approximately 5,700 residents in St. Louis in 1811. Today an estimated 11 to 12 million live in the St. Louis to Memphis region.

Just in case our politicians haven’t offered you enough to worry about. Don’t forget about Mother Nature!