Earthquake Up-date! Indiana? Really?

In a somewhat strange year for earthquakes in the continental United States, yesterday it was Indiana's turn to rumble.

You may recall the July quake of a very similar magnitude that rocked central Maryland. I do. It jarred me out of my early morning hazy sleep. And once I realized that an overloaded monster dump truck was not, in fact, about to descend upon my cozy little second story bedroom; the more lucid realization that it was only an earthquake was quite comforting.

In October, a sister quake gave the inhabitants of central Virginia a similar thrill.

And In November a rather larger quake occurred off of the coast of New Jersey/New York to little fanfare because of it's depth and distance in the Atlantic--but no where near to the mid-Atlantic rift.

Combine these with an ongoing and unusual series of quakes (dozens and dozens of them) in the mid-Oklahoma area over the past several months, and one has a reason to be at the very least curious about the present state of movement in the North American Continental Plate.

2010 has seen catastrophic shifts in the both the Pacific and Caribbean plates as testified to by the quakes in Haiti, Chile, Mexico and New Zealand. And the continental United States, though not know for seismic activity of any regular sort, has been visited on occasion in its history by some of the most amazing earthquakes.

Everyone knows about the infamous New Madrid Earthquake; but what most people don't know is that the New Madrid event was actually a series of quakes, a couple of which were nearly beyond imagining for the range of effected landmass. The event began in the wee hours of the middle of the night on December 16, 1811 when a quake which historians put at a 7.7 by modern calculations rattled the middle of the continent at New Madrid (Missouri). Within 24 hours there were reports of at least 3 more major aftershocks. And earth continued to rumble locally until January 23, 1812 when it let loose again. This time the quake is believed to have hit 7.5 on the modern Richter Scale. And on February 7, 1812 the final member of the triad occurred with an epicenter just south of the original quake at Reelfoot on the Missouri Tennessee border and was as powerful as the first quake at 7.7.

Culling historical records indicates that in the 90 days between December 16, 1811 and March 15, 1812 there were no less than 3 quakes in excess of 7.0; seven aftershocks in the 6.0-6.9 range, some of which were centered in Arkansas making them separate quake events of their own, and about one hundred in the range of 5.0-5.9. The ground was in nearly constant motion as another 90 or so quakes occurred in the 4.0-4.9 range and 1,800 tremors in the 3.0-3.9 range. I'm sure it gave a some people in the area "religion"!

During the major quakes framing this seismic event, ancient faults slipped and large areas of land shifted up and down as much as 10 meters (the height of a 3 story building). The pressure was reported to have opened fissures in the ground from which were ejected awesome amounts of sand and coal. The sunken land adjacent to the Mississippi River cause the water of the river to flow into the sunken land contributing to claims that the waters of the Mississippi south of the event flowed backward from the Gulf of Mexico for days. And modern evidence supports the enlargement of Lake St. Francis in eastern Arkansas where the ground sank.

Back then the quakes toppled simple structures as far away as Cincinnati, Ohio. Extrapolating an event of similar magnitude by today's population, the devastation would dwarf anything that has come before it. Imagine rings of destruction extending outward in 100 mile radii.

Ring #1 - clips Memphis, Tennessee

Ring #2 - Evansville, Indiana, Saint Louis, Missouri, Nashville, Tennessee; and clips Jefferson City & Springfield, Missouri, and Little Rock Arkansas.

Ring #3 - Springfield, Illinois, Indianapolis, Indiana, Louisville, Kentucky, Chattanooga Tennesse, Huntsville & Birmingham, Alabama; clips Kansas City, Missouri, Peoria, Illinois, Frankfort & Lexington, Kentucky, Knoxville, Tennessee, Montgomery, Alabama and Jackson, Mississippi.

Ring #4 - Cincinnati & Dayton, Ohio, Atlanta & Columbus, Georgia, Shreveport, Louisiana, Tulsa, Oklahoma, Topeka & Kansas City, Kansas, Chicago, Illinois, and Gary Indiana; clips Fort Wayne, Indiana, Columbus, Ohio, Macon, Georgia, Mobile, Alabama, Oklahoma City, Oklahoma, Wichita, Kansas Des Moines & Cedar Rapids, Iowa.

But the potential devastation doesn't stop there. The 1811/1812 event was felt in major ways in Detroit Michigan, Charleston, South Carolina, and church bells were caused to ring as far away as Boston, Massachusetts... If such an event were equa-distantly as powerful today, bells would ring out in Denver, Santa Fe, El Paso and Tampa.

Lest you doubt this degree of intense and lessor activity, we witnessed something very similar in the aftermath of the Chilean earthquake with multiple and nearly daily aftershocks in the 5.0-6.9 range for months after the original quake and a far greater elevation of quake activity in the same range as far north the boarder with Peru (hundreds of miles). It's only been in the last month that activity around this event has calmed down.

And there have been other major quakes along the same fault line. The next one occurred in 1843. One in 1895 that was felt over a similar area with some major damage, as well. These subsequent 1843 & 1895 events are largely lost to history.

So what's happening?

We live on a planet that moves. Sometimes it moves with horrific violence, and most of the time, it doesn't. All we know for sure is that it will move again. It will likely move again in this region, but when exactly, no one has yet figured out a way of predicting. Are the recent quakes in Indiana, Maryland, Virginia, and Oklahoma omens of a larger event or harbingers of tectonic pressures relieved and forestalled? No one has the answer to that one, either.

This is the burden of such finite beings living upon a planet who's life cycles shame glaciers by its pace. Yet change it will. And cope with the changes we will, too.