« Federal Agencies Remapping Coastal Areas Damaged by Hurricane Sandy | Main | Big Changes In The Weather Pattern Equals The Hottest Temperatures Of 2013 In Our Area! »

08/22/2013

Massive Sinkhole In Louisiana ... Does That Indicate A Major Earthquake Coming From New Madrid Fault?

Check out this amazing footage of a sinkhole swallowing a huge cluster of trees in Assumption Parish, Louisiana...

 

Video Courtesy: RearNakedSmoke

A sinkhole is a natural depression or hole in the ground caused by some form of collapse of the surface layer. Some of them are caused by natural processes but others can be attributed to human activity. For example, the rare but still occasional collapse of abandoned mines and salt cavern storage in salt domes in places like Louisiana, Mississippi and Texas.

More commonly, sinkholes occur in urban areas due to water main breaks or sewer collapses when old pipes give way. They can also occur from the overpumping and extraction of groundwater and subsurface fluids.

Now that we know why these sinkholes occur, it raises another question that has come up in the past. Are these sinkholes are a sign of a major earthquake along the New Madrid fault?

New Madrid Fault

 

If you didn't know, the New Madrid fault is a major fault line that runs from western KY/ TN through MO / AR. This fault line has been responsible for some monster earthquakes in our region. Here is a look at the area per the USGS...

Blog1
In the early 1800s, there was a serious of huge earthquakes that occurred along the New Madrid fault causing extensive damage to the region. Purdue University's Eric Calais posted a great image showing a "Shake Map" for the major December 16, 1811 earthquake.

Blog2

The USGS recounts the series of earthquakes from 1811 - 1812 which are really the legendary earthquakes in modern times for our region. These earthquakes created some incredible events including very rare sand blasts! Here is a look at a historical look at these events per the USGS...

 

A Sequence of Three Main Shocks in 1811-1812

This  sequence of three very large earthquakes is usually referred to as the New  Madrid earthquakes, after the Missouri town that was the largest settlement on  the Mississippi River between St. Louis, Missouri and Natchez, Mississippi. On  the basis of the large area of damage (600,000 square kilometers), the  widespread area of perceptibility (5,000,000 square kilometers), and the complex  physiographic changes that occurred, the New Madrid earthquakes of 1811-1812  rank as some of the largest in the United States since its settlement by  Europeans. They were by far the largest east of the Rocky Mountains in the U.S.  and Canada. The area of strong shaking associated with these shocks is two to  three times as large as that of the 1964 Alaska earthquake and 10 times as large  as that of the 1906 San Francisco earthquake. Because there were no seismographs  in North America at that time, and very few people in the New Madrid region, the  estimated magnitudes of this series of earthquakes vary considerably and depend  on modern researchers' interpretations of journals, newspaper reports, and other  accounts of the ground shaking and damage. The magnitudes of the three principal  earthquakes of 1811-1812 described below are the preferred values taken from  research involved with producing the 2008 USGS National Seismic Hazard Map (http://pubs.usgs.gov/of/2008/1128/).

 

A Robust Aftershock Sequence for each Main Shock

The  first principal earthquake, M7.7, occurred at about 2:15 am (local time) in  northeast Arkansas on December 16, 1811. The second principal shock, M7.5,  occurred in Missouri on January 23, 1812, and the third, M7.7, on February 7,  1812, along the Reelfoot fault in Missouri and Tennessee. The earthquake ground  shaking was not limited to these principal main shocks, as there is evidence for  a fairly robust aftershock sequence. The first and largest aftershock occurred  on December 16, 1811 at about 7:15 am. At least three other large aftershocks  are inferred from historical accounts on December 16 and 17. These three events  are believed to range between M6.0 and 6.5 in size and to be located in Arkansas  and Missouri. This would make a total of seven earthquakes of magnitude M6.0-7.7  occurring in the period December 16, 1811 through February 7, 1812. In total,  Otto Nuttli reported more than 200 moderate to large aftershocks in the New  Madrid region between December 16, 1811, and March 15, 1812: ten of these were  greater than about 6.0; about one hundred were between M5.0 and 5.9; and  eighty-nine were in the magnitude 4 range. Nuttli also noted that about eighteen  hundred earthquakes of about M3.0 to 4.0 during the same period.

 

Large Area of Damaging Shaking

The first earthquake of  December 16, 1811 caused only slight damage to man-made structures, mainly  because of the sparse population in the epicentral area. The extent of the area  that experienced damaging earth motion, which produced Modified Mercalli  Intensity greater than or equal to VII, is estimated to be 600,000 square  kilometers. However, shaking strong enough to alarm the general population  (intensity greater than or equal to V) occurred over an area of 2.5 million  square kilometers.

 

Shaking Caused Sand Blows, River Bank Failures, Landslides, and  Sunken Land

The earthquakes caused the ground to rise and fall -  bending the trees until their branches intertwined and opening deep cracks in  the ground. Deep seated landslides occurred along the steeper bluffs and  hillslides; large areas of land were uplifted permanently; and still larger  areas sank and were covered with water that erupted through fissures or  craterlets. Huge waves on the Mississippi River overwhelmed many boats and  washed others high onto the shore. High banks caved and collapsed into the  river; sand bars and points of islands gave way; whole islands disappeared.  Surface fault rupturing from these earthquakes has not been detected and was not  reported, however. The region most seriously affected was characterized by  raised or sunken lands, fissures, sinks, sand blows, and large landslides that  covered an area of 78,000 - 129,000 square kilometers, extending from Cairo,  Illinois, to Memphis, Tennessee, and from Crowley's Ridge in northeastern  Arkansas to Chickasaw Bluffs, Tennessee. Only one life was lost in falling  buildings at New Madrid, but chimneys were toppled and log cabins were thrown  down as far distant as Cincinnati, Ohio, St. Louis, Missouri, and in many places  in Kentucky, Missouri, and Tennessee.

A notable area of subsidence that formed during the February 7, 1812,  earthquake is Reelfoot Lake in Tennessee, just east of Tiptonville dome on the  downdropped side of the Reelfoot scarp. Subsidence there ranged from 1.5 to 6  meters, although larger amounts were reported.

Other areas subsided by as much as 5 meters, although 1.5 to 2.5 meters was  more common. Lake St. Francis, in eastern Arkansas, which was formed by  subsidence during both prehistoric and the 1811-1812 earthquakes, is 64  kilometers long by 1 kilometer wide. Coal and sand were ejected from fissures in  the swamp land adjacent to the St. Francis River, and the water level is  reported to have risen there by 8 to 9 meters.

Large waves (seiches) were generated on the Mississippi River by  seismically-induced ground motions deforming the riverbed. Local uplifts of the  ground and water waves moving upstream gave the illusion that the river was  flowing upstream. Ponds of water also were agitated noticeably.

 

Surface Deformation--Evidence for Pre-Historic  Earthquakes

The Lake County uplift, about 50 kilometers long and 23  kilometers wide, stands above the surrounding Mississippi River Valley by as  much as 10 meters in parts of southwest Kentucky, southeast Missouri, and  northwest Tennessee. The uplift apparently resulted from vertical movement along  several, ancient, subsurface faults. Most of the uplift occurred during  prehistoric earthquakes. A strong correlation exists between modern seismicity  and the uplift, indicating that stresses that produced the uplift may still  exist today. Within the Lake County uplift, Tiptonville dome, which is about 14  kilometers in width and 11 kilometers in length, shows the largest upwarping and  the highest topographic relief. It is bounded on the east by 3-m high Reelfoot  scarp. Although most of Tiptonville dome formed between 200 and 2,000 years ago,  additional uplifting deformed the northwest and southeast parts of the dome  during the earthquakes of 1811-1812.


1811, December 16, 08:15 UTC Northeast Arkansas -  the first main shock
2:15 am local time
Magnitude ~7.7

This powerful earthquake was felt widely over the entire eastern United  States. People were awakened by the shaking in New York City, Washington, D.C.,  and Charleston, South Carolina. Perceptible ground shaking was in the range of  one to three minutes depending upon the observers location. The ground motions  were described as most alarming and frightening in places like Nashville,  Tennessee, and Louisville, Kentucky. Reports also describe houses and other  structures being severely shaken with many chimneys knocked down. In the  epicentral area the ground surface was described as in great convulsion with  sand and water ejected tens of feet into the air (liquefaction).


1811, December 16, 13:15 UTC Northeast Arkansas -  the "Dawn" Aftershock
7:15 am local time
Magnitude ~7.0

A large event felt on the East Coast that is sometimes regarded as the fourth  principal earthquake of the 1811-1812 sequence. The event is described as  "severe" at New Bourbon, Missouri, and was described by boatman John Bradbury,  who was moored to a small island south of New Madrid, as "terrible, but not  equal to the first". Hough believes that this large aftershock occurred around  dawn in the New Madrid region near the surface projection of the Reelfoot fault.


1812, January 23, 15:15 UTC, New Madrid, Missouri
9:15 am local time,
Magnitude ~7.5

The second principal shock of the 1811-1812 sequence. It is difficult to  assign intensities to the principal shocks that occurred after 1811 because many  of the published accounts describe the cumulative effects of all the earthquakes  and because the Ohio River was iced over, so there was little river traffic and  fewer human observers. Using the December 16 earthquake as a standard, however,  there is a general consensus that this earthquake was the smallest of the three  principals. The meizoseismal area was characterized by general ground warping,  ejections, fissuring, severe landslides, and caving of stream banks.


1812, February 7, 09:45 UTC, New Madrid, Missouri
3:45 am local time,
Magnitude ~7.7

The third principal earthquake of the 1811-1812 series. Several destructive  shocks occurred on February 7, the last of which equaled or surpassed the  magnitude of any previous event. The town of New Madrid was destroyed. At St.  Louis, many houses were damaged severely and their chimneys were thrown down.  The meizoseismal area was characterized by general ground warping, ejections,  fissuring, severe landslides, and caving of stream banks.

 

Could These Sinkholes Occurring In Louisiana Indicate The New Madrid Fault Is Waking Up???

 

Are these sinkholes a sign of the New Madrid fault is getting ready to unleash another major earthquake? WFIE in Evansville interviewed Dr. Paul Doss who is a professor in geology from the University of Southern Indiana last year. Some of his responses should help many of you that are concerned. When WFIE asked Dr. Doss if there is a relation between sinkholes & earthquakes and here was his reply...

 

"It is very difficult for me to envision there is any sort of a linkage at all,"  said Dr. Paul Doss, USI Geology Professor. "We have no evidence what so ever  that anything like this would be a precursor to an earthquake. If an earthquake  were to happen now, it would be purely coincidence," said Dr. Doss."

 

 In addition to this report, we have had no indications or warnings from the USGS stating a major quake is immenent along the New Madrid Fault.

 

 

While the USGS still warns the New Madrid Fault is "at Significant Risk for Damaging Earthquakes", it has no statement that one is immenent. In addition, the USGS is not warning that there is any link between the two sinkholes / "fracking areas" in Louisiana and an earthquake along the New Madrid Fault. It still appears the New Madrid fault has the potential for another large damaging earthquake in it's future, but I just wanted to address that there is no data to support the need for any of you to worry anymore than normal right now after the appearance of these sinkholes.

 

-Rick DeLuca

 

Rick

https://www.facebook.com/RickDeLucaWeather

 

Comments

Feed You can follow this conversation by subscribing to the comment feed for this post.

This particular sinkhole is the result of salt dome collapse caused by mining. The state of Louisiana is suing Texas Brine over it ... http://www.nola.com/politics/index.ssf/2013/08/louisiana_sinkhole_jindal_sues.html

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment