Friday, December 13, 2013

New Madrid Fault

Peter over at Bayou Renaissance Man did a post about Prepping and Earthquakes. It just so happens that I did a report on this subject when I was in college. It was a short writing assignment that was given to us each week, and that week's report just happened to be on the New Madrid Fault. Much of that report applies to preppers as much as is it applies to emergnecy response areas. Here is a copy of that report, with the most boring and technical portions removed:

In 1811 and 1812, the New Madrid area in the boot heel of Missouri was struck by a series of six to nine earthquakes that ranged from an estimated 7.0 to 8.8 on the Richter scale, and there were also numerous smaller aftershocks, and no fewer than 18 of these quakes were felt along the Atlantic seaboard. The seismic waves were felt as far as 2000 km away (Quebec) and caused damage over an area greater than 500,000 square km. Damage caused by the quakes was limited, as the area was populated by less than 4,000 people at the time. This area is known as the New Madrid Seismic Zone (NMSZ) and is the location of the rift where the North American Continent nearly split apart 3 million years ago.

 A similar scenario playing out today would be devastating for a number of reasons. Population densities are much higher than they were during the 1811-1812 events, and a large earthquake in the area today would affect as many as 3 million people.  Infrastructure in the area was not constructed with earthquake protection in mind, and many structures in the area are built upon fault lines, as evidenced by the numerous sand boils in the area.

There are areas in the NMSZ where crops cannot grow, and this makes that land relatively cheap to buy, and for this reason many governments buy this land for infrastructure like roads, radio repeater sites, power generation, and placing pipelines. The reason that this land is so cheap is that the soil is contaminated with salty sand that has boiled up from deeper regions of the earth where faults are located, as earthquakes disturb the land. There are five major gas pipelines and two crude oil pipelines that pass directly over the fault zones, and at one point, they pass over a fault line at nearly the same point, with less than 10 miles separating four of the pipelines. NASA has estimated that gas line ruptures and the ensuing explosions at that point would be so large that their reflections would be visible as they bounced off the moon.

 In the short term, responders would have to deal with all of the standard problems associated with large disasters: fire, loss of personnel, casualties to the population, etc.. Other problems would complicate this, including the loss of electrical and natural gas supplies, and the difficulty in getting aid into the area due to the loss of Mississippi river bridges. The loss of communications would also complicate response to the area, and make coordination of resources nearly impossible.

The long term effects of losses of this infrastructure would be devastating to the population and problematic for emergency responders, not only within the earthquake zone, but in areas served by this infrastructure. The loss of five of the nine gas pipelines from the Texas/Louisiana gas fields to the industrial areas of Chicago and the Ohio valley would likely cause widespread disruption of energy and heating service in those areas. Loss of the I-40 bridge in Memphis could potentially cause transportation delays, as the loss of this bridge would cause land traffic detours of more than 300 miles and make the Mississippi River impassible to water transport. Transformers lost as a result of failures to the electrical grid could take eight to twelve months for replacement.

To combat this, the following steps need to be taken:
* Bridges and other existing structures, including emergency operations centers, need to be hardened against earthquakes
* Radio repeater sites need to be located away from sand boils, and mobile repeaters mounted on trailers need to be accessible.
* Responders need to ensure that they have a disaster plan in place, and local authorities need to ensure that they are prepared to use the National Incident Management system to coordinate amongst themselves and the local utility providers.
* National guard planners from the potentially most affected states of Missouri, Illinois, Arkansas, Tennessee and Mississippi need to be ready to coordinate supply deliveries.

Some of these steps have already been taken. Bridges and vital facilities are being retrofitted, and should be able to withstand a magnitude 7 earthquake in the future. Of course, it remains to be seen how they will withstand multiple events of this magnitude, or how a magnitude 8 earthquake will affect them.

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