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40 days and counting?... Earthquake!
All right, I hope I'm kidding -- but something that I've researched for ongoing Alfreda stories is the New Madrid earthquakes. The first major quake of the sequence occurred on December 16, 1811. It was probably around 7.0 on the Richter scale, and woke people as far away as New York City and Charleston, SC. New Madrid, by the way, was in Missouri and on the Mississippi River.
How bad was the sequence that ran until February -- and the aftershocks that were experienced months after that?
The Mississippi River ran backwards for several days. (This was the perception of eyewitnesses. This was probably seismic wave activity -- but it did fill a newly-sunken area and create a lake!)
Ground uplifts and drops of from 1.5 to 5 meters happened.
Huge fissures opened in the earth, swallowing homes.
Reelfoot Lake was formed during the last major quake in February 1812.
So -- what do we know? We know that the third largest cluster of quakes since the European settlement of North America took place around New Madrid, Missouri. These faults effect the largest square mile area in the United States. We know that the area registers tiny quakes all the time -- but it's been over 100 years since even a moderate quake.
"The lack of apparent land movement along the New Madrid fault system has long puzzled scientists. In 2009 two studies based on eight years of GPS measurements indicated that the faults were moving at no more than 0.2 millimeters (0.0079 in) a year.[20] This contrasts to the rate of slippage on the San Andreas Fault which averages up to 37 mm (1.5 in) a year across California." (From Wikipedia)
This suggests that if you live in this area, knowing what to do in the event of an earthquake might be worthwhile reading.
So far I haven't found anything that suggests the recent Oklahoma earthquakes were caused by these faults. That's another restless spur of the earth.
How bad was the sequence that ran until February -- and the aftershocks that were experienced months after that?
The Mississippi River ran backwards for several days. (This was the perception of eyewitnesses. This was probably seismic wave activity -- but it did fill a newly-sunken area and create a lake!)
Ground uplifts and drops of from 1.5 to 5 meters happened.
Huge fissures opened in the earth, swallowing homes.
Reelfoot Lake was formed during the last major quake in February 1812.
So -- what do we know? We know that the third largest cluster of quakes since the European settlement of North America took place around New Madrid, Missouri. These faults effect the largest square mile area in the United States. We know that the area registers tiny quakes all the time -- but it's been over 100 years since even a moderate quake.
"The lack of apparent land movement along the New Madrid fault system has long puzzled scientists. In 2009 two studies based on eight years of GPS measurements indicated that the faults were moving at no more than 0.2 millimeters (0.0079 in) a year.[20] This contrasts to the rate of slippage on the San Andreas Fault which averages up to 37 mm (1.5 in) a year across California." (From Wikipedia)
This suggests that if you live in this area, knowing what to do in the event of an earthquake might be worthwhile reading.
So far I haven't found anything that suggests the recent Oklahoma earthquakes were caused by these faults. That's another restless spur of the earth.
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