Which major US city is the next to die?

Politics and religion
21

[quote=“Phil_Stein”]

Umm, look here:
http://www.eas.slu.edu/Earthquake_Center/SEISMICITY/newmadrid1975-1995.html

The New Madrid Fault line lies about 175 miles south of St. Louis. An 8.5 at New Madrid would cause a lot of damage in St. Louis, but the distance would mute the effect. And St. Louis does have earthquake aware buildings and building codes. Can’t speak to the other stuff on your list, and I don’t want to minimize New Madrid, but the earthquake risk in St. Louis is notably less than in San Fran or L.A., which basically sit on top of fault lines.[/quote]

I’ve read different assessments of the New Madrid threat, Phil, most of which state that seismic building codes are sorely lacking throughout the region. This may be changing due to increased awareness, but older construction not compliant with new codes still abounds. Here’s a link to a recent article on this topic. I’ve pasted a relevant quote below:

The New Madrid fault system states are at risk for several reasons: several densely populated cities, buildings that are not reinforced and predate modern building codes, and rural counties that either lack building codes entirely or don’t have the resources to enforce them.

Organizers hope having this year’s National Earthquake Conference in St. Louis – which began Sunday and lasts through Thursday – will focus attention on the possibility that a large-magnitude quake could shake the central United States within the next 50 years, and to motivate government agencies and communities to better prepare themselves.

Missouri Seismic Safety Commission Chairwoman Phyllis Steckel said that one of the state’s biggest problems is that counties most at risk – like those in the Missouri Bootheel – don’t have the human or financial resources to enforce building codes that would help structures withstand an earthquake.

Steckel said most major metropolitan areas do have enforced building codes, but they usually apply to structures built after the codes were instituted. Older structures have less protection.

22

Was just going to post this.

Terrorists need to get in on this action. Use a nuke to cause a mega tsunami that would decimate the entire eastern seaboard of the United States. All without setting foot in the US.

23

Was just going to post this.

Terrorists need to get in on this action. Use a nuke to cause a mega tsunami that would decimate the entire eastern seaboard of the United States. All without setting foot in the US.[/quote]

That is essentially the plot of Michael Crichton’s latest novel “State Of Fear.” Just substitute western for eastern.

24

I am not sure how any Tsunami could hit Seattle or it’s suburbs in the south. The wave would literally have to travel up the Strait of Juan De Fuca, turn south, travel a while, then turn again. But if Rainier goes, man, we’re all fucked. And I mean ALL. The whole world will be a little cooler.

25

http://www.google.com/search?hs=Vm6&hl=en&lr=&client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&q=seattle+tsunami+hazard+map&btnG=Search

The short version is “oh shit.”

26

The southern suburbs are at risk from Ranier, not a tsunami. Seattle itself is vulnerable, however. Tsunami waves can do exactly what you have described. They reflect off coasts, turn, bounce, etc. Here’s a link to a Time Magazine article that mentions this. I’ve seen other, more authoritative references for this, but cannot find them tonight.

Additionally, the link here describes the possible consequences of a smaller, more local fault very near to Seattle proper.

Edit: ah, bingo. This is what I was looking for. The following quote is especially relevant:

Another finding that may be of critical importance to communities farther from the coast, on the Strait of Juan de Fuca and in Puget Sound, was the Dec. 26 tsunami’s ability to retain its force even when going around corners. Scientists studying the waves’ behavior in Sri Lanka were stunned to see what happened on the leeward side of the island nation.

27

If I’m reading that map right, it’s bad, but not catostrophic. Most of the highlighted area is industrial in nature… the Port of Seattle and that big chunk south of Seahawk Stadium and the ballpark. (Oh the flip side, Starbucks HQ would be wiped out, and millions of coffee lovers everywhere would frickin’ freak.)

28

What about the 5 meter hit on downtown? That’s a 15 foot wall of water.

29

Thankfully I live in a more protected area away from the water!

30

The thing to remember about the map you’re looking at is that it’s showing the projected waves from the Seattle fault proper, not the Cascadia subduction zone. As a result of the Indonesian tsunami, we now realize that tsunami’s can turn corners and change direction without losing appreciable force. This means that Seattle could be hit by wave heights equal to those on the coast of Washington. A huge, Indonesian-like subduction quake there (which has happened in the past and will certainly recurr) would generate waves from 33 to 80 feet high, depending on the model. That would be horrific for Seattle. Read the third link in my previous post (from the Seattle Post-Intelligencer) for more details.

31

I wonder if we could build something to stop big waves from making it in. Might as well start now.

32

[quote=“Phil_Stein”]

Umm, look here:
http://www.eas.slu.edu/Earthquake_Center/SEISMICITY/newmadrid1975-1995.html

The New Madrid Fault line lies about 175 miles south of St. Louis. An 8.5 at New Madrid would cause a lot of damage in St. Louis, but the distance would mute the effect. And St. Louis does have earthquake aware buildings and building codes. Can’t speak to the other stuff on your list, and I don’t want to minimize New Madrid, but the earthquake risk in St. Louis is notably less than in San Fran or L.A., which basically sit on top of fault lines.[/quote]

Not to be argumentative with a fellow St. Louisan, but that’s not what I remember hearing about St. Louis.

Back in 1989 when Iben Browning “predicted” a major New Madrid earthquake that didn’t happen, the Post-Dispatch ran a series of articles on the effect such a seismic event might have, and one of the conclusions drawn by the Army Corps of Engineers is that St. Louis and many of the cities in the region would be in much worse shape than might be expected given it’s distance from the fault. They cited the disproportionate number of brick buildings in the area as one reason for their findings. Bricks don’t like earthquakes much, I guess.

Perhaps they were trying to sell papers, but the P-D articles at the time painted a bleak picture for the city if/when the “big one” on the New Madrid line hits.

“C’mon do what you did
Roll me over New Madrid
Shake my baby and please bring her back.
'Cause death won’t even be still
Caroms over the landfill
Buries us all in his broken back.”

33

There’s another complicating factor, too. For reasons unclear to me, quakes in the central part of the U.S. are felt for much greater distances than those on the west coast. The usual figure I’ve seen for this difference is a factor of 10. In other words, being 175 miles from the epicenter of the New Madrid fault is like being 17.5 miles away from the San Andreas. For comparison purposes, LA is a lot farther from the San Andreas than that.

Again, no clue why this is the case.

Edit: here is a link to a page with a map demonstrating this difference. It compares shaking intenisities of 2 similarly sized quakes, the New Madrid events and the 1906 San Francisco quake. Scroll down to the “Regional Geology” section for the map.

Edit 2: Even better map here

34

How soon can I move into outer space?

35

Here’s some New Madrid stuff:

From Southeast Missouri State University’s Center for Earthquake Studies
PDF Here

The Highest Earthquake Risk in the United States outside the West Coast is along the New Madrid Fault. Damaging temblors are not as frequent as in California, but when they do occur, the destruction covers over more than 20 times the area because of underlying geology.

A Damaging Earthquake in this Area, 6.0, reoccurs about every 80 years (the last one in 1895). In 2002, the U.S. Geological Survey released new earthquake probabilities for the New Madrid Seismic Zone. For a magnitude 6.0 – 7.5 or greater earthquake, there now is estimated to be a 25-40% chance in 50 years. The results would be serious damage to schools and masonry buildings from Memphis to St. Louis.
[snip]

When Will Another Great Earthquake Happen the Size of Those in 1811-12?

Several lines of research suggest that the catastrophic upheavals like those in 1811-12 visit the New Madrid region every 500-600 years. Hence, emergency planners, engineers, and seismologists do not expect a repeat of the intensity of the 1811-12 series for at least 100 years or more. However, even though the chance is remote, experts estimate the chances for a repeat earthquake of similar magnitude to the 1811-1812 New Madrid earthquakes have changed from the 1985 estimates of 2.7 – 4.0% probability in 50 years to a 7 - 10% probability.

Re: San Fran earthquakes:
From http://quake.wr.usgs.gov/research/seismology/wg02/

On the basis of research conducted since the 1989 Loma Prieta earthquake, U.S. Geological Survey (USGS) and other scientists conclude that there is a 62% probability of at least one magnitude 6.7 or greater quake, capable of causing widespread damage, striking the San Francisco Bay region before 2032.
[snip]
We have used the term “major” earthquake as one with M>=6.7 (where M is moment magnitude). As experience from recent earthquakes in Northridge, California (M6.7, 1994, 20 killed, $20B in direct losses) and Kobe, Japan (M6.9, 1995, 5500 killed, $147B in direct losses), earthquakes of this size can have a profound impact on the social and economic fabric of densely urbanized areas.

The measurement standards aren’t identical (6.0-7.5 for New Madrid, vs. a hard 6.7 for San Fran), and the time frame for the estimate is 27 years for San Fran, vs. 50 years for New Madrid, but that gives some ballpark data.

A New Madrid quake of 6.0-7.5 ~=25-40% within 50 years. A San Fran quake of 6.7 ~=62% in 27 years.

New Madrid is a fairly isolated location, compared to San Fran. On the other hand, the quote says a New Madrid fault would affect 20x the area, because of geography. But 20X the area is not 20X the distance (area increases as the square of distance), so, if the 20X area figure is correct, New Madrid affects out from the epicentre about 4.5X further than S.F.

Finally, I tried to get more accurate distance information. Downtown St. Louis is about 150 miles from the town of New Madrid. Downtown Memphis is about 100 miles from New Madrid.

36

Good stuff there, Phil. I hope every danger zone in the U.S. gets some serious, sustained attention as a by-product of Katrina. Long overdue, in my mind.

37

Man, I’m lucky I survived my spring visit to Charleston, SC!

38

Good thing Bush & Co gutted FEMA’s mitigation programs.

39

Good thing Bush & Co gutted FEMA’s mitigation programs.[/quote]

Talk about a 1-track mind… :roll:

40

Good thing Bush & Co gutted FEMA’s mitigation programs.[/quote]

Talk about a 1-track mind… :roll:[/quote]

Maybe he’s addicted to love.