What is the Reelfoot Rift?

The Reelfoot rift consists of two major basins, separated by an intrarift uplift, that are further subdivided into eight subbasins bound by northeast- and southeast-striking rift faults. The rift is bound to the south by the White River fault zone and to the north by the Reelfoot normal fault.

What caused the Reelfoot rift?

The Reelfoot Rift extends for 150 miles through four states, no less than three miles underground and often more. The rift is a weak spot in the center of North America, formed 750 million years ago by a mantle plume — a “hot spot” deep inside the Earth.

When and how did the Reelfoot rift form?

…from activity occurring along the Reelfoot Rift, an ancient subterranean rift zone thought to have developed some 500 million years ago after geologic forces pulled the region in a northwest-southeast direction.

What is a Reelfoot reverse fault?

The Reelfoot fault is interpreted to be a re- verse fault in a left stepover between two northeast-striking right-lateral strike-slip zones that define the seismicity of the New Madrid seismic zone (Russ, 1982; Gomberg, 1993; Schweig and Ellis, 1994; Kelson et al., 1996).

Where is the Reelfoot fault?

It appears to have occurred on Reelfoot fault, a reverse fault segment that crosses under the Mississippi River just south of Kentucky Bend and continues to the east as the Lake County Uplift.

That Time North America Tried to Tear Itself Apart

How overdue is the New Madrid Fault?

Projections. The USGS has projected that for an earthquake of magnitude 7.5 to 8.0, the probability for occurrence is approximately 7-10% over the next 50 years. For a quake of 6.0 to 7.0, the probability is 28-46% over the next 50 years.

What would happen if the New Madrid fault line went off?

Nearly 200 schools and over 100 fire stations would be damaged; 37 hospitals and 67 police stations would be inoperable the day after the earthquake in the state of Missouri. Thousands of bridges would collapse and railways would be destroyed, paralyzing travel across southeast Missouri.

Where is the New Madrid Fault line in Tennessee?

The New Madrid seismic zone (NMSZ), located in the central Mississippi River Valley, is known for its historically devastating earthquakes of 1811–1812 and its continued seismicity (Figure 1; Penick, 1981; Csontos and Van Arsdale, 2008). Lake County is a small, rural, county in northwestern Tennessee (Figure 1).

What fault line is in Tennessee?

Answer and Explanation: Tennessee has two seismic zones, the New Madrid Seismic Zone and the East Tennessee Seismic Zone. This has led to a lot of fault lines in Tennessee.

What type of fault line is the New Madrid?

The New Madrid seismic zone of the central Mississippi River valley has been interpreted to be a right-lateral strike-slip fault zone with a left stepover restraining bend (Reelfoot reverse fault).

Why does the New Madrid seismic zone exist?

The Reelfoot rift is identified today as a subsurface system of fractures and faults in the earth's crust. New Madrid seismicity is spatially associated with the Reelfoot rift and may be produced by movement on old faults in response to compressive stress related to plate motions.

How common are earthquakes in Missouri?

Most Missourians are familiar with the large 1811-1812 earthquakes that occurred in the New Madrid Seismic Zone (NMSZ) in southeast Missouri and it extends into a multi-state area. However, Missouri experiences small earthquakes nearly every day.

Which of the following statements best describes elastic rebound theory?

Which of the following statements best describes elastic-rebound theory? Energy builds up as elastic strain in rocks. When the applied stresses become overpowering, the rocks at the fault rupture.

Why did the Mississippi river run backwards?

On February 7, 1812, the most violent of a series of earthquakes near Missouri causes a so-called fluvial tsunami in the Mississippi River, actually making the river run backward for several hours.

How long did the Mississippi river flow backwards?

The storm surge ahead of Hurricane Isaac made the Mississippi River run backwards for 24 hours. US Geological Survey (USGS) instruments at Belle Chasse in Louisiana recorded the flow of the river, finding it running in reverse on Tuesday.

What were the effects of the Reelfoot earthquake?

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.

Why is Tennessee having so many earthquakes?

“Earthquakes frequently occur in Tennessee because the state's eastern and western areas sit along seismic zones where earthquake activity happens more frequently – the East Tennessee Seismic Zone and the New Madrid Seismic Zone (NMSZ).

When was the last major earthquake in Tennessee?

Apart from the 1811–12 New Madrid earthquakes, only three major events have struck the state of Tennessee, in 1843, 1865, and 1895.

Where is the biggest fault line in the world?

The Ring of Fire is the largest and most active fault line in the world, stretching from New Zealand, all around the east coast of Asia, over to Canada and the USA and all the way down to the southern tip of South America and causes more than 90 percent of the world's earthquakes.

When was the last time the New Madrid Fault went off?

The last strong earthquake (magnitude 6.7) in the NMSZ occurred near Charleston, Missouri on Oct. 31, 1895. A magnitude 6.3 earthquake near Lepanto, Arkansas on Jan. 5, 1843 and was the next prior earthquake of this magnitude.

When was the last time the New Madrid Fault was active?

It was December 16, 1811, and it was the first of at least three very large (M7 or greater) earthquakes and thousands of aftershocks to rock the region that winter, with the last occurring on February 7, 1812.

Is Nashville on a fault line?

Tennessee is in two seismic zones, the New Madrid and the East Tennessee zone.

Was Reelfoot Lake created by an earthquake?

Reelfoot Lake, shallow lake on the boundary between Lake and Obion counties in northwestern Tennessee, U.S., near Tiptonville. It was formed by the earthquakes that occurred along the New Madrid Fault in the winter of 1811–12.

Where is the New Madrid Fault and when was its last major earthquake?

Earthquake of January 23, 1812

The main shock occurred at 9:15 am, and its magnitude was estimated at 7.5. The location of the earthquake's epicentre is controversial, but it is thought to have been located in the vicinity of New Madrid, Missouri, along a fault that runs perpendicular to the Reelfoot Fault.