Lissa graduated from NC State University with a Bachelor's Degree in geology in 2015. Learning and writing about science is her passion.
When You Least Expect It, You Can Experience An Earthquake
Something very unusual happened during my first geology class at North Carolina State University in a 3rd story lecture hall. The professor was going through the syllabus when suddenly the building began to shake. The projector rattled until it fell off the stand, cutting our presentation short, and students' papers fluttered to the floor from their desks.
The door, which had been gently cracked, was slammed shut. Noticing the rising panic among his students, our professor motioned for everyone to calm down and went to check something on his computer. With more than a little surprise, he proclaimed that most of us had just experienced our first earthquake.
At magnitude 5.8, the 2011 Virginia earthquake was one of the biggest earthquakes the east coast had experienced since the days of Christopher Columbus, costing between 200 million and 300 million dollars in damage and affecting states as far away as New York and Ohio. Despite the magnitude of its property damage, we were lucky that nobody died from this earthquake. Sadly there have been many earthquakes where that wasn't the case, but with each one that occurs, scientists learn more about how earthquakes work, and engineers apply that knowledge to protect people and property from future disasters. This particular earthquake was very unusual because it didn't happen near a current plate boundary; however, that isn't the only time this happened.
During the pioneers' time, three earthquakes shook the remote settlement of New Madrid, Missouri, from December 1811 to February 1812. These earthquakes were some of the strongest ever experienced on the continent, only beaten by the magnitude 9.2 quake that leveled Anchorage, Alaska in 1964. Most earthquakes (the ones strong enough for you to hear about, anyway) occur along plate boundaries, but these powerful earthquakes came from an ancient fault line that slipped within the crust.
Seismic evidence shows that 750 million years ago, the supercontinent Rodinia rifted along that fault line and North America split off as the continent of Laurentia. Even though the eastern portion of North America is not near a current plate boundary, forces from the Mid-Atlantic ridge's push can create stresses that sometimes reopen the earth's old wounds. After 750 million years, the cracks are still there, creating a weak zone around New Madrid that could still be prone to major earthquakes in the future.
December 16th, 1811: Quake #1
The first New Madrid earthquake happened on December 16, with an estimated magnitude of 8.1. New Madrid had about 1000 people living in the city, located on the southeastern tip of Missouri, and every single one of them was woken up at 2 AM to sheer chaos. Anyone still awake at that hour and standing up was knocked off their feet, and the earth shook so violently that it forced many people to vomit in their beds. Fissures up to 5 miles long opened in the ground and released toxic sulfurous gas that killed livestock, and the farmland around the city was inundated with sand, coal, and dirty water. Sand boils, a phenomenon where pressurized groundwater wells up through beds of sand and explodes like a volcano, dotted the borders of the Mississippi River, and the world's largest sand boil was created during this earthquake.
John Reynolds, the future governor of Illinois, recounted his experience of the earthquake in his biography: his father had jumped out of bed screaming that "the Indians were attacking the house", and the family laughed at first, but with the aftershock that occurred at 7:15 in the morning they became worried that their house would not survive the damage. However, since it was a log cabin, they were relatively safe since wooden buildings tend to hold up well in earthquakes. Many of their neighbors in stone houses were not so lucky; the survivors became homeless. A tent city was constructed for them, which may be why the death toll in the following earthquake wasn't as high. Without a building falling on you, it's much easier to survive an earthquake.
January 23, 1812: Quake #2
The second quake, in January 1812, had a slightly smaller magnitude at 7.8, but a much wider effect. Rocks toward the inside of a tectonic plate can carry earthquake waves farther since they are less broken up by faults. Dolley Madison, the first lady at the time, was woken up in Washington DC, and thousands of acres of forest were flooded from the Mississippi River overflowing its banks. Many new lakes were created from this earthquake, like Reelfoot Lake in Tennessee and Big Lake in Arkansas. But this is small compared to what the third quake in February did...
February 7, 1812: Quake #3
The grand finale quake came in at a whopping 8.8 magnitude, and it was felt as far north as the Canadian province of Ontario. Church bells rang through Boston, New York, and Toronto, and brick walls in Cincinnati crumbled like Humpty Dumpty had sat on them. The Mississippi River swallowed thirty boats as huge waterfalls were created from the subsidence of the earth in the span of seconds. Whirlpools churned the water and made it impossible to escape, and the water turned dark brown from all of the sand and coal flooding in, making it even more difficult to rescue the passengers. Many of their bodies were never found. Also, the elevation of the land surged or dropped up to 30 feet in some areas, and quite a few of the islands in the middle of the river were destroyed by violent flows of water, eliminating the hideouts of river pirates.
Eyewitnesses wrote that the Mississippi River ran backwards for several hours afterwards, rerouted north by the sheer force of the tremors. Flatboat pilot John Weisman was on the river during this earthquake, delivering a shipment of whiskey to New Orleans. He miraculously survived this phenomenon, attaching his boat to a sandbar to avoid a surprise waterfall and making a break for the shore when the retrograde current became less intense. He encountered a Native American whom he described as a chief once he was on land; the chief joked that the reversing of the river as the Father of Waters getting drunk on his whiskey. The poor captain had to return to town with his crew on foot, but found the town almost completely destroyed. After a few days he and his crew managed to relocate their boat and sail to New Orleans, bearing the meager remains of his shipment.
The Aftermath of the New Madrid Earthquakes
The death toll of the three earthquakes was estimated to be around 1000 people, but it could be higher since there wasn't much known about the Native American tribes in the area; we do know that a Native American village about 15 miles south was flooded, but it is not known how many people perished. The owner of the very first steamboat, Nicholas Roosevelt, was touring the Mississippi promoting his new ship. He managed to survive the treacherous river during the December quake, but he and his family were chased away by natives from that village blaming their "fire-ship" for the earthquakes. Because of the Native Americans' fear and resulting attacks, steamboats took a while to catch on.
After the first quake, the inhabitants of New Madrid learned some interesting tricks to help them survive later earthquakes. One trick that saved some people was to chop down tall trees and lay them east-to-west, perpendicular to the fault line. When the fissures opened in the ground, people could hang onto the trees to prevent themselves from falling in. Farmers also began paying more attention to the behavior of animals. Cows running home and snakes fleeing down the roads clued them in that an earthquake was coming, and they had a few vital minutes to get to safety.
The New Madrid fault line has still been active in recent years, with over 4000 minor earthquakes occurring since 1974. In a report from November 2008, FEMA warned that a major earthquake is likely to happen in the next 50 years, and that the resulting disaster would cause economic losses much higher than that of Hurricane Katrina. Memphis is one major city near the fault line that would likely be affected, so the buildings and infrastructure there are being evaluated for earthquake safety. Hopefully, we can learn from our past and minimize our losses in the future.
- Strange Happenings during the Earthquakes | New Madrid, MO - Official Website
A recounting of the New Madrid earthquakes on the official town website.
- Earthquakes on the Mississippi: The New Madrid Seismic Zone | HowStuffWorks
Will a town in southern Missouri be the epicenter of the next 'big one'? HowStuffWorks looks at the science behind the New Madrid Seismic Zone.
- Breakdown: Why the Mississippi River once flowed backwards
When people think of earthquakes in the United States, they tend to think of the west coast. But earthquakes also happen in the eastern and central U.S.
- 1811–1812 New Madrid earthquakes - Wikipedia
The Wikipedia article on the New Madrid earthquakes.
- New Madrid Compendium Eyewitness Accounts - CERI - The University of Memphis
New Madrid Compendium Eyewitness Accounts
- 2011 Virginia earthquake - Wikipedia
The 2011 Virginia earthquake article on Wikipedia.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2022 Lissa Clason