19 Mar 2011 Earthquake: What is making the ground tremble beneath our feet?

by Levi Gilbert

Arkansans across the 501 are experiencing an unsettling feeling. A recent swarm of earthquakes originating in northern Faulkner County, headlined by a 4.7 magnitude quake Feb. 27, have rattled residents’ walls and spirits. 

“It’s a little disconcerting,” Greenbrier resident Nichole Clark said. “We’ve felt [the earthquakes] last year, but they were vary sparse. But you can’t deny the recent ones. They occur in clusters and can be very frequent, sometimes at least one an hour.” 

Nichole and her husband, Jeremy, live in the North Heights in Greenbrier, close to the city limits border between Greenbrier and Guy. The couple was forced awake when a 4.3 magnitude earthquake struck at 2:13 a.m. on Feb. 18.

“It was just a big boom,” Jeremy said. “I shot up out of bed. You could feel the house shake, and the bed shook, too.”

Picture frames rattled on the walls, and the couple said it sounded like someone had shot a shotgun in the backyard.

“At first it freaked me out, and I was a little fearful about it,” said Nichole. “Now we’re just trying to be smart about it. We bought earthquake insurance for $115 a year. The next step we took was taking an inventory of our home. We took pictures of everything and stored it on an online program, just in case of any emergency really – not just for earthquakes.”

INSURANCE

The Clarks aren’t the only ones who have decided to purchase earthquake insurance. The recent outbreak has led many to inquire for an insurance quote.

“We’ve definitely seen an increase in the number of inquiries, quotes and policies,” said Roe Henderson of Shelter Insurance in Conway. “There’s definitely been a surge on it. It’s not my preferred way of selling insurance, but that’s just kind of how it’s happened. Most people are in a wait-and-see mode.

“The biggest hurdle people seem to have is that it’s not necessarily cheap. The standard deductible is 10 percent of whatever your house is insured for. I’ve always carried it since I’ve been in the business. We live in a fault area – this is one of the fingers off of the New Madrid fault in Missouri. Can you stand $200 or $300 on a premium? You can recover from a $10,000 deductible a lot easier than you can recover from $100,000 in damage.”

Henderson said rates could vary depending on other factors, such as brick veneer siding as opposed to cheaper wood siding.

“Most policies will cover content, but you need to make sure you get contents coverage along with it,” Henderson said. “You need to check coverage for other structures, too, such as pools or storage buildings. That coverage isn’t automatic with earthquake insurance like it can be with your homeowner’s policy.

“It’s a tough deal. On one hand, I think people should really take a hard look at earthquake insurance, but on the other hand, I don’t want them to feel coerced into it. I don’t like to sell policies during a fire sale, but at the same time, we are getting a warning. It’s no different than buying fire insurance. The threat of a fire is always there, but you sure hope it doesn’t happen. In this area, I would tell people they need some earthquake coverage.”

‘TWO DIFFERENT THINGS’

This year marks the 200th anniversary of the largest earthquake in Arkansas history – the 7.7 magnitude New Madrid earthquake of 1811. That earthquake was part of a number of shocks that occurred between 1811-1812. The New Madrid seismic zone stretches southwest from New Madrid, Mo., and covers parts of Illinois, Indiana, Arkansas, Kentucky, Tennessee and Mississippi.

While many 501 residents are familiar with the New Madrid fault, experts say that is not what is causing the recent swarm of earthquakes.

“We’re talking about two different things,” said David Maxwell, director of the Arkansas Department of Emergency Management. “The recent earthquakes in Central Arkansas are different than the New Madrid fault zone, which has a much greater potential for a dramatic, devastating earthquake.

“As we know from back in the ‘80s with the Enola swarm, there are some fractured areas in the Central U.S. that have the potential for seismic activity.”

What is unnerving many throughout the 501 is that geologists aren’t sure if the recent activity is a natural occurrence.

“It’s something we’re studying right now,” said David Johnston, an earthquake geologist for the Arkansas Geological Survey. “There are a couple of scenarios: Either the activity is natural seismicity, similar to the Enola swarm in the ‘80s and in 2001, or we could be seeing human-induced seismicity.”

Geologists are studying to determine if the seismic activity might be related to natural gas drilling activities, such as fracturing, or “fracking,” and injection wells. Fracturing is a common drilling practice by which pressurized water is used to create fractures in the ground to release natural gas. The wastewater from fracturing is then pumped and stored in local injection wells.

Two natural gas companies – Chesapeake Energy and Clarita Operating – temporarily ceased operations of injection wells near Greenbrier and Guy as requested by the Arkansas Oil and Gas Commission until further geological studies can be made. This recent move is in conjunction with a six-month moratorium that began in January on new injection wells in the area.

“Last year we installed six permanent seismic monitoring stations across the state at various state parks,” Johnston said. “And since we’ve had this recent activity, we’ve put in a local seismic network in Central Arkansas to augment our permanent stations. This gives us a better, accurate idea of where the epicenter is and how deep the earthquakes are occurring. We are continuing to monitor and study until we can make some determination on what is causing the activity.

“Since the 4.7 magnitude quake, we’ve had more than 7,000 felt reports on the U.S. Geological Survey website. We got reports from Missouri, Oklahoma, Tennessee and Mississippi.”

PREPARATION IS KEY

While the earthquakes have caused some unwanted stress and fear for 501 residents, it has also led many to research earthquake awareness. Johnston said awareness and preparedness is the key, and for the Clarks, that key is helping to ease the fear.

“Getting the insurance is really about peace of mind,” Jeremy said. “Most people that are feeling them are wondering what’s causing them. When will it stop? Is it going to get worse? We don’t want to live in fear that our house might come down and we’re not prepared to handle it.”