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EARTHQUAKES, 1811-12
Description of the New Madrid Earthquake
courtesy of The Tennessee
Historical Society
Between mid-December 1811 and mid-March 1812 a series of catastrophic
earthquakes shook West Tennessee and the rest of the Central Mississippi
Valley. Judging from reports and eyewitness accounts, the quakes would
have measured among the highest ever recorded on the modern Richter
scale. Some reports said that the quakes were strong enough to awaken
sleepers in Washington, D.C., and allegedly some tremors were felt
twelve hundred miles away in Quebec City, Canada.
The first of these historic quakes occurred in the St. Francis
River area of northeast Arkansas; the second struck five weeks later and
several miles to the northeast. Two weeks after that the third and
strongest of the three quakes hit the area, with its epicenter still
further north, at the little river port town of New Madrid, Missouri.
The last of these three quakes is estimated to be the strongest ever
recorded on the North American continent.
Geologists associate this early quake activity with the New Madrid
or Central United States seismic zone. This ill-defined series of deeply
buried faults runs roughly parallel to the Mississippi River Valley. The
zone extends from Cairo, Illinois, south through Missouri to Marked
Tree, Arkansas. A side branch also extends into the Reelfoot Lake region
of northwest Tennessee.
Since the affected region was a sparsely settled frontier, few
written accounts exist of the early quakes. According to a few personal
diary entries and scanty eyewitness accounts quoted in local newspapers,
the endless days and nights of earth tremors and thousands of
aftershocks must have been dreadful to experience. Few settlers had ever
experienced a quake.
The quakes caused much destruction along the Mississippi River as
far south as present-day Memphis and as far up the Ohio River as
Indiana. During the strongest of the quakes, great cracks and fissures
opened and spewed out sand and water. Gaping crevices formed, some
twelve feet wide and deep and more than twenty feet in length. Low
waterfalls developed at points along the Mississippi in the vicinity of
New Madrid. They were short-lived, however, in the soft sediments of the
river valley. Shifting currents and changing flows along the
Mississippi, Ohio, Arkansas, and other rivers created and destroyed
islands, sandbars, and other familiar features. The quakes caused waves
to rush over river banks. Return currents washed countless limbs and
even whole trees into the main channels. Massive log jams formed, making
navigation even more perilous.
Many boats capsized, and cargoes and crews were never seen again.
Seasoned riverboat pilots had to deal with whole new rivers. Cracks and
fissures, downed trees, and other obstacles made roads and trails
impassable. Massive landslides occurred along the Mississippi and Ohio
River bluffs from Memphis to Indiana. Some ground areas rose or fell as
much as twenty feet relative to the surrounding landscape. An eighteen-
to twenty-acre area near Piney River in Tennessee sank so low that the
tops of the trees were at the same level as the surrounding ground.
Whole forests sank below their original level and filled with water to
form swamps and shallow lakes. The eighteen-thousand-acre Reelfoot Lake
was either formed or enlarged during the 1811-12 earthquake episode. In
other areas, lakes and swamps rose to higher elevations. Soon their
waters drained away or evaporated. In time they evolved into prairies
and upland forests. Much of this land now supports Tennessee cotton and
soybeans.
As devastating as these early quakes were, destruction in human
terms was light. Population was sparse, and Indians, traders, and
settlers were quite self-sufficient, capable, and resilient. Due to a
lack of census records and other reliable counts, the exact number of
people who perished as a result of the quakes will never be known.
Allen R. Coggins, Knoxville
Use by permission of the Tennessee
Historical Society, copyright The Tennessee Encyclopedia of History
and Culture.
www.tennesseehistory.org.
Ballad by Larry Holder to commemorate the 200th anniversary of the New
Madrid Earthquakes of 1811-1812....The
Days The Earth Would Not Stand Still
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