There are certain areas in the world that are prone
to earthquakes. California, Japan, and other regions sitting on fault
lines all run the risk of these geological upheavals, and the people who
live in these areas are well aware of it, living in a constant haze of
fear in the back of their minds that one may strike at any moment. Yet
there have been other areas of the world that do not face such anxiety,
where earthquakes should really be one of the least of their worries,
but despite this there have been anomalous quakes that have come and
gone on to become baffling mysteries. Such is the case of a series of
earthquakes that hit the Midwest region of the United States in the 19th
century, which were not only odd that they happened at all, but also
rather weird in that they are some of the most powerful quakes the
country, and indeed the world, has ever seen.
The morning of December 16, 1811 probably started much as any other
day in the central Mississippi Valley of the United States, yet at
approximately 2:15 AM the entire region was jolted and viciously rocked
by a powerful tremor which would later be determined to have originated
at an epicenter in northeast Arkansas. Considering that this was the
Midwest of the United States, probably the last thing that was on
anyone’s mind was that they would be struck by an earthquake, and not
only was it unusual, but it was exceptionally potent, measuring a
magnitude of 7.5 to 7.9, causing massive damage, and felt as far away as
New York City, Boston, Ohio, Massachusetts, Montreal, and Washington
D.C. Even more terrifying still was that this was just the beginning,
with a 7.4 magnitude aftershock striking later that same day, and
unfortunately more was to come.
Over the next few months the region would be hit by more earthquakes
measuring between magnitude 7 and 8, as well as countless aftershocks,
until by March of 1812 the region had been terrorized by thousands of
powerful temblors. Two of the earthquakes after the initial one were
just as intense as the first, if not more so, such as a magnitude 7.8
quake on January 23, 1812, and the third major quake on February 7,
1812, which was estimated as being as much as a massive magnitude 8.8,
all interspersed by countless aftershocks that all caused havoc,
capsized boats, leveled forests, and even reshaped the landscape by
forming islands, new waterfalls, massive sand boils, geysers, numerous
deep fissures said to have even swallowed people alive, and creating
Reelfoot Lake. What would go on to become the New Madrid Earthquakes,
named after the Mississippi River town of New Madrid, would be felt to
some degree over an area of around 1 million square miles fanning out
from the central Midwest, and making it all even more frightening were
some of the odd phenomena surrounding them.
A commonly reported phenomenon during the quakes was the presence of a
loud roaring noise, like thunder or explosions, which was reported by
countless locals and which made it all the more ominous. There were also
reported the presence of dark clouds in the sky and a sort of foul
smelling smog that descended upon the land to make breathing difficult
and obscure vision, as well as the smell of sulphur and mysterious
flashes of light in the sky, likely the result of a phenomenon known as seismoluminescence.
Also rather unusual is that there were reports from boatmen of the
Mississippi River actually flowing in the opposite direction at the time
of the original quake and for up to several hours after. One rather
frightening report of all of this mayhem was given by an eyewitness who
illustrated the chaos:
On the 16th of December, 1811, about two o’clock, a.m.,
we were visited by a violent shock of an earthquake, accompanied by a
very awful noise resembling loud but distant thunder, but more hoarse
and vibrating, which was followed in a few minutes by the complete
saturation of the atmosphere, with sulphurious vapor, causing total
darkness. The screams of the affrighted inhabitants running to and fro,
not knowing where to go, or what to do—the cries of the fowls and beasts
of every species—the cracking of trees falling, and the roaring of the
Mississippi— the current of which was retrograde for a few minutes,
owing as is supposed, to an irruption in its bed— formed a scene truly
horrible.
It must have seemed like the end of times, and of course considering
all of these strange phenomena orbiting it all and the fact that the
Midwest region had never experienced anything like this before, there
were immediately dire omens about what it all meant. Many highly
religious people believed it to be a sign from God, and stated that many
of the details could be found in Bible scripture. Native tribes of the
area also had their theories that it was tied to their angry great
spirits, and it did not go unnoticed that a comet not seen since the
time of Ramses II in Egypt had arrived in the previous months and was at
its brightest during the earthquakes, making it believed to have been
some sort of portent to disaster.
Although the sparsely inhabited nature of the region at the time
meant that the death toll was kept to a minimum, the New Madrid
earthquakes were, and still are, considered to be the most powerful and
most prolonged earthquakes to hit the United States east of the Rocky
Mountains in recorded history, which is quite odd and surprising for an
area of the United States not known for its earthquakes, and which does
not lie on the edge of any of the earth’s 15 tectonic plates. Despite
all of the more supernatural explanations that have popped up in the
wake of the quakes, there is likely a more scientific explanation, but
it is poorly understood, made even more difficult because the region has
had so few earthquakes in its history as a basis of comparison.
What is now called the New Madrid Seismic Zone is a bit of an anomaly
to say the least. In most cases, earthquakes occur along the edges of
Earth’s tectonic plates, where friction between two of the plates
sliding against or pushing or pulling each other causes the tremors, but
that is not the case for the New Madrid earthquakes since they
originated practically right in the center of one of these plates. There
have been all manner of hypotheses for why this zone should cause these
powerful quakes, such as that it is the result of magma pushing up from
beneath the earth, a weakened crust in the area, an undocumented fault
line, the result of the release of stress at the surface from the
retreat of glaciers, local changes to the mantle flow, and others.
One of the most popular recent theories is that the quakes were
caused by a spider web of fissures underground called the Reelfoot Rift,
formed between 700 million and 540 million years ago when the ancient
supercontinent of Rodinia broke apart and split, creating a system of
fissures and weakened, fractured crust deep in the earth that is
possibly prone to earthquakes, although not in the traditional sense.
Despite all of these theories, no one is still really sure why these
powerful quakes should hit the region, and research is ongoing. One
seismologist at the University of Memphis in Tennessee, Christine
Powell, has said of it all:
Here, in the center of a plate, we don’t have a theory
that we can attribute the earthquakes to. So in order to understand why
they’re occurring, you have to think outside the box.
Whatever the reasons for the New Madrid Earthquakes may be, it was
certainly not a one-time freak occurrence. Ever since these earthquakes,
the region has been consistently hit with numerous temblors, to the
tune of about 4,000 mild to moderate quakes since 1974, and it is
thought that there is a 25 to 45% chance of a magnitude 6 or greater
earthquake in the area within the next 50 years, which would be
devastating to the now highly populated area. In the end we are left
with quite the geological mystery. How is it that not only was there a
strong series of earthquakes, but also some of the most relentless and
intense the country has ever seen, right out in the middle of nowhere
where no earthquake should have been in the first place? It is testament
to the fact that there are still mysteries of our planet we do not
fully understand, and until we do we can only wait and see if there will
be another repeat of that 1811 catastrophe.
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