http://weblogs.baltimoresun.com/news/politics/blog/2008/05/china_quake_should_wakeup_us.html

I knew immediately when I heard the stories about the recent China 7.9 earthquake and the epicenter mid-continent on a large continent, and how the waves travelled hundreds, over a thousand miles. How people observed the ground undulating, how the main shock lasted for many long moments, was devastating and had severe effects on the environment, and how strong aftershocks went on for days, months, even more than a year.

That's the New Madrid earthquake of 1811-1812. It's also the recent Chinese earthquake. I have been to a lot of workshops over the years on the earthquake threat in our region. When an area with a thick covering of sediment receives severe seismic shocks, not only does it travel long distances, but it affects different kinds of soil in different ways. In river bottoms often is sandy, loose, well drained soils. Those soils also have a very high water table. Those soils are called "liquifaction" soils, and they shake like jello when they receive such a strong seimic shock. There are rivers everywhere in the world. Most of the big cities are on rivers, because there is a lot of flowing water to supply a large population. That makes these cities very vulnerable during strong seismic events.

During the New Madrid earthquake of 1811-12, the Mississippi River flowed backwards for days, carved a new channel, cut off part of Kentucky, formed Reelfoot lake, and was felt as far away as Boston. Strong aftershocks went on for over a year. The shaking lasted a long time. People observed the ground undulating. http://www.essortment.com/all/newmadrideart_pvm.htm

It's not a matter of if for this region. It's a matter of when. The question is whether the area will be prepared. Right now it isn't. If it happens sooner than later, we will see similar results to what is happening now in China. In the region now we have chemical plants, nuclear fuel facilities, coal fired power plants, large petroleum storage facilities, pipelines, etc. etc. etc. We need to prepare better, no doubt.