Sunday, November 19, 2006

Letting my geek flag fly.

As a geology major, every once in a while I'd have moments where I really and truly understood how big the Earth really is, where I'd just get it all of a sudden. It usually came in a flash and only lasted for a few seconds, as if it was too big of an idea to wrap my head around for long.

It happened a few months ago at work, while I was idly reading a poster we have about black holes and for a split second comprehended how vast the universe truly must be, and just kind of went "Whaaaa...?" for a moment, and then it was gone.

A week or two ago, I was doing some research for a geology workshop for kids, and I came across a cool website that documents earthquake history in the U.S. Since I live in the Midwest, I grew up hearing about the New Madrid fault and the nearly-mythic tales of the New Madrid quakes of 1811 / 1812. We heard so much about them as kids that I just sort of figured that everyone knew about them, that they were in history books and stuff. I mentioned something about them to KWJ that day while we were talking, and she'd never heard of them before. Since she lives in California, I told her that I guess when you've got the San Andreas on your doorstep, the New Madrid fault system doesn't really rank very high on the list of things you worry about.

Speaking of the San Andreas, I find it fascinating and mind-boggling that it's actually visible at the surface:

San Andreas fault in the Carrizo Plain, central California
(Photo by Robert E. Wallace)

Anyway, I found some of the historical accounts on the earthquake site, and while I knew about the most famous stuff, like the Mississippi allegedly running backwards (which was actually an illusion created by waves caused by the quake) and church bells ringing in Boston, some of this stuff I'd never heard before. It was definitely of the scope to make my brain go *boinnnng*. Here are some highlights:

"On the basis of the large area of damage (600,000 square kilometers), the widespread area of perceptibility (5,000,000 square kilometers), and the complex physiographic changes that occurred, the Mississippi River valley earthquakes of 1811-1812 rank as some of the largest in the United States since its settlement by Europeans. 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."

I watched a special about the 1906 San Francisco quake on the History Channel back in April when the did they did a big 100-year-anniversary thing. It's crazy to think back on what that show talked about and then try to magnify that by ten.

"At the onset of the earthquake the ground rose and fell - bending the trees until their branches intertwined and opening deep cracks in the ground. Landslides swept down the steeper bluffs and hillslides; large areas of land were uplifted; and still larger areas sank and were covered with water that emerged through fissures or craterlets. Huge waves on the Mississippi River overwhelmed many boats and washed others high on the shore. High banks caved and collapsed into the river; sand bars and points of islands gave way; whole islands disappeared."

Okay, that would be freaky as hell to see today, and we understand what earthquakes are. I can't imagine what it would be like to see that if you didn't really know what an earthquake was all about. I'd probably think the world was ending or something.

"Other areas subsided by as much as 5 meters, although 1.5 to 2.5 meters was more common. Lake St. Francis, in eastern Arkansas, which was formed by subsidence, is 64 kilometers long by 1 kilometer wide. Coal and sand were ejected from fissures in the swamp land adjacent to the St. Francis River, and the water level is reported to have risen there by 8 to 9 meters."

Holy. Crap. As scary as it would be, I think I would actually be excited to see a sand blow, let alone freaking COAL blowing out of the earth. That is INSANE. My little geology nerd heart is totally pitter-pattering.

If you're a big geek, too, and want to read more about the quake, you can go here. It's not too scientific mumbo-jumbo-y. Here's a PDF that talks about earthquake hazards in the Midwest.

Reading: still working on the fabulous Sunshine, which I'm officially adding to my Christmas list

Playing: Maybe This Christmas Too?


  1. I might have nightmares when I go to bed, but overall, excellent work, Rock Goddess.

  2. One might even say, Geo-geeklicious.

  3. Yay, geo-geeks unite!

    And I always figured the alleged reverse-flow of the Mississippi was due to to uplift...where part of the river was uplifted, so the water flowed backwards, and when the uplifted land subsided, there was left Reelfoot lake in Kentucky. I know I read that somewhere...but hellifiknow where. :)

    Y'know...sometimes it makes me kinda proud to live in the New Madrid fault area, and others scared outta my freakin' mind. Cuz you know E'ville would either slide into the river due to liquifaction, or parts collapse into the abandoned coal mines. But, the New Madrid quakes were so much cooler than those wimpy Cali quakes.

  4. And if the New Madrid didn't get us, the Wabash Valley Fault System might.

    But hell, anywhere you go...there's something crazy that could happen, geologically speaking. ;)