35 years ago, Memphians were sent reeling by the effects of an earthquake centered in Marked Tree, Arkansas. Seismologists believe the chances of a magnitude 6 or better quake hitting near Memphis are up to 40 percent within a narrowing 50 year window.
-Earthquakes occur without warning
-Memphis sits in the New Madrid Seismic Zone, which affects 8 states
-A 7 magnitude quake would destroy most of city infrastructure
-72 hours is the typical time frame survivors must wait for help
-Every home should have earthquake survival kit, plan
FOX13's Les Smith takes a look at what might happen if 'the big one' struck the Bluff City, and why 72 hours could make the difference between surviving it or not.
Predicting the Next Earthquake
No clock will pinpoint the appointed time. It's not a matter of "if". It is only a matter of "when" it will come.
According to University of Memphis earthquake researcher and geologist Gary Patterson, "The fact we haven't felt a big one in our lifetime, it doesn't matter. Earthquakes happen based on the geological time scale not on the human life span."
"Most people realize that we're on a fault line, that we could have an earthquake. But, it doesn't mean it's going to happen here. It can happen anywhere," warned Wayne Nichols, Mayor of Marked Tree, Arkansas.
Located 40 miles west of Memphis, the small and friendly community of Marked Tree, Arkansas doesn't outwardly belie its geographical importance. But, as the southern most point of the iconic New Madrid Seismic Zone history records, Marked Tree has served as a barometer for some of the greatest seismic activity in the United States. Most notably, it spawned the legendary earthquakes of 1811 and 1812 that changed the mid-western landscape forever.
Elaine Clyburn with the Red Cross said, "This zone, it really affects 8 states in the Seismic Zone region and almost everyday there are small quakes."
Learning from the Past
Of the 25 largest quakes ever registered in the Central United States, Marked Tree has made the list twice. In January 1843 it was a 6.4 quake. Just 35 years ago in 1976, a 5.0 magnitude sent tremors that did more than just scare Memphians, it laid open our vulnerability to earthquake damage.
"That earthquake caused damage in critical facilities: Fire Department buildings, Downtown buildings, specifically those that were unreinforced masonry structures," said Patterson. "So, if that magnitude six happened in Marked Tree, Arkansas where the 1976 earthquake happened, the damage would be significantly great. 32 times more, no, but a lot more."
It's only a matter of when it will come. It will strike with no warning, for unlike all other natural disasters that can be forecast through advanced technologies, earthquakes defy prediction. What's left for researchers are probabilities based on windows of time.
"The probability of a magnitude six in the New Madrid Seismic Zone is between 25 to 40 percent in a 50-year window," added Patterson.
A Vulnerable Infrastructure
So, what could Memphis face in terms of damage and lives lost? Since most statistics or predictions in that area aren't made public by emergency management officials for fear of panic, there are some obvious harbingers of what the devastation could be. Like the 6.3 quake that hit New Zealand this year, most of the initial damage will occur among the nearly 2,300 unreinforced buildings in Shelby County. Based on the factors of the quake's path, structures and soils, downtown Memphis and the River Bluffs will be the most susceptible to extensive damage.
"The ground motion from a 7 here in Memphis would be fairly heavy and there'd be very strong shaking," said U of M earthquake researcher Steve Horton. "The damage would potentially be large."
"The gas lines to things will shift underground as the ground moves and ripples, the gas leaking out will catch fire when there's a spark. So fires are another thing to take care of," said Steve Masler with the Pink Palace Museum. "Electricity, telephone wires, data, cables, those things could be broken. So, the first hour or so after a major quake could be a lot of confusion and damage."
Besides the total or partial collapse of brick and mortar commercial buildings, a high percentage of hospitals, fire stations and schools will all be vulnerable to damage. Although the Hernando-Desoto Bridge has been earthquake reinforced, other bridges, roads and highways haven't been. Add on what could be weeks or months of accompanying aftershocks, possible contaminated rivers, creeks and air pollution.
In 2000, a FEMA study estimated quakes could do $17 million worth of damage in Memphis. However, consider this: 2003's straight line winds fueled "Hurricane Elvis" which knocked out power for weeks to 310,000 MLGW customers, and in the end cost the city $14 million for clean-up and restoration. Given the broad range of devastation earthquakes can inflict, costs of repairs would be astronomical by comparison. But even more long term and causing possibly more irreparable harm would be the wounded psyches of the quake's victims.
"Earthquakes are scary. They can automatically call a sense of dread in people because they can't be predicted and the impacts are poorly understood," said Patterson. "Earthquakes occur without warning. There is no alarm. They do occur and you have to immediately enact your plan."
"In reality, if we had a major earthquake or any other kind of a major disaster, for several days people would really be on their own and depending on their own resources," Clyburn said.
72 Hours of Survival
72 hours could be the difference between life and death in the chaotic aftermath of an earthquake. It's the amount of time you may spend alone or with your family before you can find help or help gets to you. What if it happens and you're away from home, say at your place of work? Think self-preservation.
Horton said, "Generally speaking what's recommended is that you stay where you are until the earthquakes over and then you go out."
"It's important not to go back into buildings that have been damaged because the primary earthquake will often times damage a building, and then the aftershocks will cause them to collapse or part of them to fall," Masler added.
While survival techniques in regards to securing food, water and other necessities could prove arduous away from home, in your own house an Earthquake Kit should already be packed and a family emergency plan fully discussed. The Red Cross suggests everything from canned goods (and don't forget a can opener), flashlights, batteries, a radio, vital medications, bandages and water.
"If you have household bleach you can take contaminated water and purify it," Clyburn said. "But, you have to know how many drops of bleach to how many liters of water, what size container the water is in."
If separated, already have a location to meet or a contact known to all family members. Most important of all, don't panic. If you've got a plan to survive, stick to it.
"That's a reminder for us to prepare for future earthquakes without having one."
A Country of Quakes
As most of the Mid-South sits on one of the most active fault lines in the world, most people think of California as having the most earthquake activity. In fact of the 6 worst quakes in U.S. history, California had four of them. The other two come from the New Madrid Seismic Zone.
The biggest earthquake ever recorded in the U.S. was in 1700 along the Cascadia Subduction Zone in California. That massive quake registered at a 9.0.
In December of 1811, the New Madrid Quake registered at an 8.1. Just a couple of months later in 1812, an 8.0 quake struck New Madrid, Missouri.
The great quake of San Francisco in 1906 is tied for the 5th worst quake in our country's history.
For more information about "the big one" and some resources you may need to stay safe, visit the following websites: