Scientists Warn of Devastating Earthquake… in the Midwest

When you ask someone where the next catastrophic earthquake will hit in the United States, almost everyone would say California.  Warnings of “the big one” have been in circulation for a while, from movies to government programs - everyone knows that California is the most likely spot for an earthquake disaster.

According to FEMA, “everyone” may be wrong.

From San Francisco down to Los Angeles, preparations have been made and are continuing to be made to increase the safety and awareness in the likely event of a major earthquake in the near future.  FEMA’s concern now shifts towards Missouri and the surrounding states where a hotbed of earthquake activity is surrounded by populated areas that are currenly unprepared for a major earthquake.

They should be, as two of the strongest earthquakes in American history happened there and is likely to have a repeat soon.

Recently FEMA issued a statement that this concern must be addressed more seriously. To put this into perspective, the area of impact of the zone’s 1895 earthquake with a magnitude of 6.8 was 7X greater than that of the 1994 Northridge, CA, quake of approximately the same magnitude.  Future earthquakes in the area have the potential to be much stronger than that.

FEMA and most of the earthquake research world is now focused on the New Madrid Seismic Zone. The zone, named for the town of New Madrid in Missouri’s southeast corner, is subject to frequent mild earthquakes. The area experienced two of the largest earthquakes in US history in late 1811 and early 1812. Because the area is landlocked, the impact of another large quake from this zone would be more devastating than any earthquake known in the US.

The New Madrid Quakes of 1811-1812

• They can still be seen topographically today.
• They rang church bells as far as Boston, MA.
• They were felt across 50,000 square miles, ranging from Louisiana to Maine and further south along the east coast.
• The Mississippi River was noted to have reversed its direction for a short time and ultimately changed its course.
• The area of strong shaking associated with these shocks is two to three times larger than that of the 1964 Alaska earthquake and 10 times larger than that of the 1906 San Francisco earthquake.

Effects of a New Madrid Earthquake Today

The difference between earthquakes that occur along the coastal or gulf regions versus landlocked areas can be enormous. While quakes that occur along or close to the water have the tsunami effect, and can cause a tremendous amount of damage, the area of impact is relatively small when compared to that of a land-locked densely-populated area.

Because the range of impact would span much further, there is concern over preparation for such an event. However, the New Madrid Seismic Zone is still not completely understood and therefore, it hasn’t gained as much attention as possible future California quakes. But, this zone of activity has raised some awareness and concern by FEMA, and they are now warning of it’s potential threat.

The zone still remains active today with over 4,000 epicenters reported since 1974. With the area more densely populated and with most buildings having no earthquake-resistant construction, the government is concerned. The possibility of an earthquake along this area in the next 50 years with a magnitude 6.0+ is approximately 40%, and 10% for a 8.0+ magnitude earthquake.

According to a report in Reuters, “People in a vast seismic zone in the southern and mid-western United States would face catastrophic damage if a major earthquake struck there and should ensure that builders keep that risk in mind.”

FEMA said if earthquakes strike the New Madrid Seismic Zone, they would cause “the highest economic losses due to a natural disaster in the United States.”

FEMA predicted a large earthquake would cause “widespread and catastrophic physical damage” across Alabama, Arkansas, Illinois, Indiana, Kentucky, Mississippi, Missouri and Tennessee — home to some 44 million people. Tennessee is likely to be hardest hit, according to the study that sought to gauge the impact of a 7.7 magnitude earthquake in order to guide the government’s response.

Experts have long tried to predict the likelihood of a major quake like those that struck in 1811 and 1812. Mary Walker, a FEMA spokesperson, warns, “People who live in these areas and the people who build in these areas certainly need to take into better account that at some time there IS expected to be a catastrophic earthquake in that area, and they’d better be prepared for it.”

(Sources: Reuters, Wikipedia 1 and 2, Earthquake.usgs.gov, image)

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