Shaky Ground: Will the 'Big One' Hit the Heartland?

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     In the Bible, Jesus talks about "earthquakes in various places" as signs of the end times.


As several powerful quakes rocked various places around the world last year and so far this year, many are finding those words even more compelling.

Even the heartland of America has seen an increase in the number of quakes.

The year 2010 began with a deadly earthquake in Haiti. But before the year ended, more than 20 earthquakes struck worldwide, reaching a magnitude of 7.0 or higher -- the largest number of major earthquakes in 40 years.

That trend is continuing in places like Japan, Guatamala, the India-Nepal border, and New Zealand.

"They've gone home," reported John Butterworth of Shine TV in New Zealand. "They've escaped the carnage. The destruction of their office environment. Made it home alive to find that their house has been damaged or even destroyed."

The U.S. hasn't been immune. Last year, strong earthquakes injured people in California and Oklahoma.

Fault Lines Crisscross U.S.

For years, people have talked about the San Andreas fault along the West Coast. But did you know fault lines also crisscross the heartland?

It was along one of these lines just last October where the second largest quake ever to occur in Oklahoma, struck near the city of Norman, injuring two people.

"It was felt very strongly throughout the state, from Dallas to Kansas City as well," Research Seismologist Austin Holland told CBN News. Holland works for the Oklahoma Geological Survey.

He said Oklahoma has definitely seen a spike in quake activity. More than 1,000 were recorded in 2010 alone, most too small to be felt. Before that, the largest number of quakes recorded in a year -- felt and not felt -- was 167.

"I get calls from people who are very frazzled and just want them to stop," Holland said.

Like a 'Zipper Unzipping'

Holland admitted that one reason for the significant increase in the number of quakes is more monitoring stations are now online. But that's only part of the story.

"My working hypothesis, and this certainly could change through time, is that these are small faults responding to stresses that are being built up over very long time frames from the plate boundaries," he explained.

Scientists believe the earth's crust is made up of several large plates that move relative to each other. Faults are the boundaries of the plates, and when they slip, an earthquake can happen.

"The plate boundaries are squeezing the central part of the United States from all the interactions of the tectonic plates surrounding North America," Holland said.

"You have an earthquake that occurs, and that changes the stress ever so slightly next to it, and so another earthquake occurs, and it's just sort of like a zipper unzipping," he said. "It kind of just goes down the line."

Oklahoma Quake Capital

Before 2009, Oklahomans experienced on average only about three earthquakes strong enough to be felt each year. In 2009, that number jumped to 43.

 In 2010, it skyrocketed to around 100 felt earthquakes. Many of them were felt in Jones, Okla., a small town east of Oklahoma City.

The population of Jones is only around 2,500, but the town's residents have witnessed an incredible amount of earthquakes.

"There's 700 events in just this tiny little area in Oklahoma county," Holland said.

Of those 700 events, residents felt more than 65 of them -- a huge number when you consider the entire state of Oklahoma averages only three felt quakes each year.

Ray Poland, the mayor of Jones, grew up in California, along the San Andreas fault.

"Coming from California, everybody would have thought that I would have experienced an earthquake before, but I had no idea what it was like until I'd been in Jones, Okla.," Poland told CBN News.

So far, the biggest quake in the Jones area has been around a magnitude 4.2.
"(The earthquakes have) rattled some walls, kind of shook some windows, shook some people up, but nothing where's there's been any significant damage in Jones," Poland said.

Although this increase hasn't led to much damage, Holland doesn't want residents to become complacent.

Case in point -- the Meers fault. It's the largest in Oklahoma and considered the most hazardous. Holland said its last major quake happened 1,300 years ago -- a 6.5 to 7 magnitude.

The Big One - Coming Soon?

Does that mean middle America could see a "big one" anytime soon?

"The odds are low, but it is a real possibility that an earthquake could occur somewhere in the mid-continent," Holland said.

To the east, Arkansas is experiencing a number of earthquakes as well. More than 800 have hit the north central part of the state since September. The largest one to shake Arkansas in 35 years struck in February with a magnitude 4.7.

Scientists are studying if there's a connection between the earthquakes and local injection wells. The natural gas industry injects pressurized water deep in the ground to create fractures and free the gas.

However, researchers cannot ignore that parts of Arkansas are in the New Madrid Seismic Zone - the most active earthquake zone east of the Rocky Mountains.

Grim Anniversary in the Heartland

This year marks the 200th anniversary of the infamous New Madrid earthquakes -- the most powerful series of earthquakes in American history. Striking along the fault in 1811 and 1812, the largest of the quakes was centered in the southeast Missouri town of New Madrid.

The quakes were so powerful that they changed the flow of the Mississippi River, transformed rich farmland into fields of sand, and destroyed countless structures.

A huge earthquake striking this same area today would affect around 15 million people across seven different states.

"Earthquakes are a national hazard," Dr. David Applegate, with the U.S. Geological Survey, said. "It's in these areas, away from California, away from the places we think about, where there can be some of the greatest risk."

No one can predict an earthquake, but scientists believe it's only a matter of time before another major event hits the heartland.

In fact, the federal government is so concerned that it conducted a major exercise this year to prepare agencies for the possible "big one" in middle America.