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New Madrid earthquake of 1811
On December 16, 1811, the 400 residents of New Madrid, Missouri, were shaken
out of their beds at two in the morning by a violent earthquake. Huge cracks split
the ground. The waters of the Mississippi rose and fell like a great tide. Giant
waves rose up and swept north, giving the impression that the river was actually
flowing backwards. Boats along the river were engulfed, capsized, and theeair
crews drowned.
The “New Orleans” was one of the lucky ones. The first steamboat to
ply the Mississippi River, she was embarked on her maiden voyage. At dusk she
tied up at an island in the middle of the stream. Then, in the wee hours, the
boat was nearly swamped by a series of enormous waves. As the deck pitched and
yawed, the crew and the few passengers on board held on for their lives. Later,
one of the crew said it was like being in the middle of an ocean during a violent
storm.
All along the riverbank, high bluffs crumbled into the water. Seemingly solid
ground undulated in waves. Old river channels slammed shut and new ones opened,
changing the course of the stream forever. One large lake had its water suddenly
replaced by sand. Another lake, Reelfoot, was created in a matter of moments.
Trees toppled or were drowned when the land sank suddenly beneath them. Log cabins
scattered like match sticks in New Madrid but, luckily, only one person was killed
by falling debris.
Effects of the quake were widespread. Damage was reported as far east as Charleston,
South Carolina and Washington, DC. In Boston, Massachusetts, 1,000 miles away,
church bells were made to ring. The effects of the quake were felt as far south
as New Orleans and as far north as Canada.
The gigantic shake in the early morning of December 16 was only the first in a
series of four. There was a second shock hours later. A third quake rocked the
area on January 23 and a fourth -- the biggest of all -- was felt on February
7. Between the major quakes, there were thousands of aftershocks.
It is not known how many were killed or injured in the New Madrid Earthquakes,
but casualties were probably light. In 1811-1812, the area was sparsely populated.
Today, of course, that is far from the case. If the same thing had happened in
the year 2000, say during the late afternoon, casualties would have been staggering
and property loses would tally in the billions of dollars.
Some scientists claim that the so-called “Big One” will not happen on
the West Coast at all. Rather, a surprising number of them argue that the next
sizable shake might occur along the New Madrid Fault, probably by the year 2010.
Other authorities, like The Central United States Earthquake Consortium, say there
is a 90 percent chance of a magnitude six or seven earthquake hitting the Mississippi
Valley within the next 50 years. The National Earthquake Center of the U.S. Geological
Survey (USGS) is more general in its prediction. It suggests that the possibility
of such an earthquake “might occur as soon as next year or as late as several
thousand years hence.” But all have come to the same conclusion. Disaster
will strike the Mississippi again.
The New Madrid Fault extends from eastern Arkansas to about the junction of the
Mississippi and Ohio Rivers. It is called a failed rift -- that is, a fault not
located near one of the several large tectonic plates that float on the hot mantle
of the earth. Most earthquakes -- like those in California and Japan -- occur
where the plates grind past each other. The geology in these earthquake zones
is different. The ground here is warmer from the heat coming from inside the earth
-- somewhat elastic. Not so at New Madrid.
Here the ground is cold and brittle. When it moves, there is no elasticity so
there is more widespread damage. A sizable quake, such as the ones in 1811-1812,
would cause extensive devastation and loss of life. The cities of Memphis, Tennessee,
and St. Louis, Missouri would be hit head-on. There would be enormous damage in
Kentucky, Ohio, Illinois, Arkansas, Indiana and Mississippi. Yet, some people
in these areas are barely aware that the possibility of a major earthquake exists.
However, there are voices crying in the wilderness and they are beginning to be
heard. In 1983, at the urging of the USGS, the states of Arkansas, Illinois, Indiana,
Kentucky, Mississippi and Tennessee formed the Central United States Earthquake
Consortium (CUSEC). The organization is currently embarked on an intensive program
of public education and awareness. Through their urging, for instance, earthquake
education is now included in the curriculum of public schools in many CUSEC states.
Furthermore, an extensive scientific study has been launched to study area soils
to determine where earthquake damage would be the most severe. And most of the
CUSEC states have adopted building codes with earthquake design standards to meet
the coming emergency.
Authorities in California know, even with their extensive earthquake preparations,
that if a large earthquake hits a highly populated area there will be wide-spread
devastation. The magnitude 6.7 earthquake that struck Northridge in 1994 cost
33 lives and destroyed property worth $20 billion.
How many more deaths would be caused in the vulnerable Midwest by a similar quake,
or stronger, around rush hour? The prospect is almost too fearsome to contemplate.
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