Memories of the 28th Century

They may not be as good as conspiracies, but many people that I have encountered love catastrophes, but they seem to prefer non-events and minor catastrophes, even though there have been some real dusies in the past. Right up there with the Biblical flood was the New Madrid earthquake, actually a series of earthquakes that began on December 16, 1811 and lasted until March 15, 1812. The USGS mentions three major quakes and series of aftershocks, while Jared Brooks recorded many shocks during that period (see link below). While the main events were major quakes estimated to have been about 7, or higher, on the Richter scale, the total energy of the entire series was greater than any other recorded seismic event.

The faults that produced the New Madrid quakes are at a place where earlier tectonic plates became joined to create the North American plate. It has been suggested that the quakes there and elsewhere near the middle of the North American plate could be indications that the plate is breaking up. If so, then we may have to wait a long time before there will be a sea there. The Rift Valley in Africa has been splitting apart for some millions of years, and there still isn’t even a tiny sea; although there are some dandy volcanos.

In the far distant past oceans did open up in the land that is now North America, but the rifts have disappeared under other land since then. It’s hard to be sure, but it appears that the Sea of Cortes has been getting wider for millions of years and may lead to splitting off of parts of Southern Cal., the San Andreas Fault and related faults. But that isn’t going to happen soon. No one would miss that territory, and some would even express their joy in seeing it go.

Most of the world's earthquakes and volcanos are related to the so-called Ring of Fire around the Pacific Ocean, but there are other areas where it appears that new oceans are trying to tear their ways out of deep, continental crust. The largest is the Great Rift Valley in Africa and its continuation as far North as the Sea of Galilee in Asia and through the Lakes Region in Africa. The Rift Valley is seismically active, and it is actively spreading in Ethiopia, where there are active volcanos related to it. The geology.com link is quite interesting and has some spectacular photos. Just imagine a rift valley like that in the middle of North America. Some of the other links show volcanos, and other photos of an ocean breaking out.

The National Geographic piece on rift valleys is quite nice and informative. I hadn't been aware that Lake Superior is in a rift valley that stopped spreading, the Keweenawan. The Wikipedia article is a fairly good overview of the New Madrid Seismic Zone and its potential. A related fault system is the Wabash Valley Seismic Zone, which has had quakes, but nothing of the scale of the New Madrid quake. The Wabash faults are thought to be a branch of the New Madrid fault, and they extend the potential rift valley a long way to the Northeast. That system may just be left over from the formation of North America, but it is also possible that new faults are forming that will lead to an eventual split in North America.

Some people who expect government to do everything may expect the federal government to do something about the division of North America, but if there such a split it will take millions of years or even longer. If people want to worry about such things, then remember that the Connecticut River Valle=y has been a rift valley at least twice, and it could happen again. I wanted to warn people about that happening with the Hudson River, but that doesn't seem to have as interesting a geological history, but something could change. I have read that there may be a volcanic hot spot under the Catskill Mountains, and that region is rising continuously, but that may be more connected to the Panther Mountain Structure, which is the remains of an impact crater.

This is something that becomes more interesting the more I learn about it, but I have no fear that there will be a volcano start under me within that next few years, but having a new ocean start here might be a worthy, long-term activity, but it won't even happen in my lifetime, but don't let that stop you from worrying about it. The breakup of North AMerican may not be climate change, but it will lead to future climate change due to the new mountain ranges that will be formed. 1



http://earthquake.usgs.gov/earthquak...1_overview.php
http://hsv.com/genlintr/newmadrd/
Jared Brooks and other material from St. Louis University
http://www.eas.slu.edu/eqc/eqc_quake...r_accounts.pdf
http://www.eas.slu.edu/eqc/eqc_publ/...DFs/Brooks.pdf
http://www.eas.slu.edu/eqc/eqc_quake...idGeneral.html
http://www.eas.slu.edu/eqc/eqc_quake...R.accounts.pdf
http://www.eas.slu.edu/eqc/eqc_publ/...DFs/NM_Big.pdf
http://www.eas.slu.edu/eqc/eqc_publ/...ntensities.pdf
http://www.eas.slu.edu/eqc/eqc_stude.../nicholson.pdf

Great Rift Valley
http://geology.com/articles/east-africa-rift.shtml

http://ngm.nationalgeographic.com/20...re-photography
http://www.pbase.com/bmcmorrow/image/47145980
http://www.telegraph.co.uk/news/eart...in-Rietze.html
http://ethiopianrift.igg.cnr.it/rift...seismicity.htm
http://www.volcanodiscovery.com/africa.html
On rift valleys
http://education.nationalgeographic....valley/?ar_a=1
http://en.wikipedia.org/wiki/New_Mad...ic_earthquakes
http://en.wikipedia.org/wiki/Wabash_Valley_Seismic_Zone