Earthquakes in the Midwest are not so far-fetched
By SUSAN COOPER
Staff writer
Earthquakes in Kansas? Sounds impossible but it's true.
Numerous faults, breaks in rock or soil, are located in Kansas and neighboring states. The possibility of a measurable earthquake may be greater than realized.
Of course, the Midwest could never experience a tsunami caused by an earthquake on the ocean floor, like the one that dumped tons of water and debris on the Asian continent.
There is a fault that has gained national attention — the New Madrid fault.
The New Madrid fault, the Midwest's version of California's San Andreas fault, is located along the Missouri, Illinois, Kentucky, Tennessee, and Arkansas borders.
To some scientists, the New Madrid fault is a ticking time bomb.
Rick Miller, a seismologist with the Kansas Geological Survey in Lawrence, said another "big one" will come — and when it does, Kansans will feel its effects.
"Today you'd see sheet rock splitting and foundations cracking all across Kansas," Miller said. "You'd see a few chimneys toppling."
If it were to happen, the cities of Memphis, Tenn., St. Louis, Mo., and Chicago, Ill., are likely to suffer major damage and destruction, he said.
However, Dr. Don Steeples, professor of geophysics at the University of Kansas, does not believe an earthquake at the nearby fault will affect residents in Marion County.
"No matter how big an earthquake might occur in New Madrid, there would not be serious damage in Marion County," Steeples said. "It could be felt, and some things might even fall off shelves, but there would be no significant damage and it is very unlikely there would be injuries."
The larger the earthquake, the longer it lasts. Another factor that controls duration of ground motion is distance from the epicenter.
The farther the distance, the longer it lasts. The intensity of the shaking usually decreases with distance, but duration of the shaking increases.
New Madrid fault
The New Madrid fault is the site of the largest earthquake in the history of the lower 48 states.
According to the United States Geological Survey, the hazard in this region is as high as places in California, despite a lower level of modern-day earthquake activity.
Scientists have designated this as a high-hazard region based on studies of buried "sand blow" deposits within the Mississippi River Valley.
Sand blow deposits are believed to be the byproduct of strong ground shaking associated with large earthquakes.
These deposits have been dated to about 900 A.D. and 1450 A.D., and suggest major earthquakes with magnitudes of seven or greater recur in the region approximately every 500 years, with the last one in 1811-1812.
Elsewhere scientists use the frequency of small and moderate earthquakes to estimate the likelihood of larger events, but in the New Madrid region, this rule of thumb does not appear to apply.
Dr. Ray Knox and Dr. David Stewart in the book, "The New Madrid Fault Finders Guide," state the New Madrid earthquakes were a result of slippage of rock and soil caused by prehistoric events.
These also are the reasons the scientists believe significant earthquakes could occur in the future.
Five months of terror
Three or four months prior to the earthquakes of 1811-1812, smaller tremors were almost continuously felt by residents in the fault area.
According to Knox and Stewart, there were eyewitnesses who reported hundreds of tremors.
The larger earthquakes leading up to the "granddaddy" of them all, began during the night of Dec. 16, 1811, when rocks violently shifted below the ground, west of the present-day city Blytheville, Ark.
In the morning, another large shift took place near the cities of Cooter and Steele, Mo. Later that morning, it happened again beneath Caruthersville, Mo.
Three great jolts occurred Dec. 16 with estimated magnitudes of 8.0-8.6. Big Lake, west of Blytheville, was formed that day.
Five weeks later on Jan. 23, 1812, another big shake estimated to have a magnitude of 8.4 struck north of Caruthersville.
The town of Point Pleasant, located on a point of land sticking into the Mississippi River, completely crashed into the river and was swept away without a trace.
Townspeople had fled a month earlier because of the tremors.
The largest quake was two weeks later on Feb. 7, with an estimated surface magnitude of 8.8 which was the strongest quake ever recorded in the U.S.
The energy released that day has been compared to more than 8,000 atomic bombs.
Researcher Otto Nuttli wrote that this quake caused a 60-mile rupture of the New Madrid fault.
Two waterfalls occurred on the Mississippi River, causing more than 100 people to drown. The river ran backward for several hours.
The quake also created Reelfoot Lake in northwest Tennessee.
During the five-month period, there were hundreds of earthquakes, most with magnitudes of 3.0 to 4.3.
There were no seismographs at that time, so researchers estimated the strength by studying damage reports.
Today, the New Madrid fault rattles the areas in Arkansas, Missouri, and Tennessee, 150 or more times per year. Most of the shakes are less than 3.0 in magnitude, do not cause damage, and may be felt for only a few miles.
Another 'big one'
Another large earthquake in current Kansas history was April 24, 1867, in Manhattan.
Following the quake, a two-foot wave was observed moving south to north on the Kansas River near Manhattan.
According to information from the USGS, chimneys were downed (Pottawatomie County), the side of a large building toppled (Miami County), and the earth opened up and spewed a large amount of water on a farm (Riley County).
Plaster fell from walls in Kansas City and Dubuque, Iowa. A well which was in the process of being dug was destroyed in Junction City.
Several stones were knocked off a church in Lawrence. Shingles were shaken off a building in Olathe, and walls cracked in Wamego.
Kansas earthquake history
Following the large earthquake in 1867, there were smaller earthquakes recorded in various parts of the state.
These earthquakes measured between 4.0 and 5.9 in magnitude and occurred from 1875 through 1933.
More recently, a damaging earthquake centered near El Reno, Okla., occurred April 9, 1952.
The 5.5 magnitude quake was felt most strongly at Medicine Lodge, with aftershocks observed at Kansas City.
Minor damage occurred on Jan. 6, 1956, at Kansas towns of Coats, Coldwater, Medicine Lodge, and Wilmore, and Alva, Okla.
The damage was limited to loosened bricks, cracked plaster and chimneys, and objects knocked from walls and shelves.
Another earthquake with a Kansas epicenter occurred April 13, 1961, in the same areas as the 1933 tremor in Norton County, and Furnas County, Neb.
A Nov. 9, 1968, earthquake centered in southern Illinois, was felt moderately throughout the eastern portion of Kansas.
There was a lull in significant earthquake activity until the most recent recorded earthquake occurred May 13, 1999, in Kansas City.
Steeples said the 1999 earthquake probably was a result of movement along a small fault somewhere in the Kansas City area.
The tremors could have been compounded by the possible collapse of a closed limestone mine, Steeples said, which was below the medical building that sustained damage.
According to researchers, earthquakes are occurring all the time and most aren't felt above ground.
Recent earthquake activity, provided by USGS, indicated the most recent tremors in the New Madrid area were recorded this past week with magnitudes of one and two along the Missouri-Tennessee border.
Some Kansans are likely to experience the earth move if and when the New Madrid fault shifts again. And it seems to be anybody's guess when other faults across the state may shift.
Scientists and their equipment are limited — the rest is up to nature.
So, yes, Dorothy, there are earthquakes in Kansas.
