gnarlydorkette
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*Bear with me as I possess the role of being a teacher! I thought people will find this VERY interesting if they like rocks and stuff... hopefully I don't bore you too much...
Earthquakes have plagued the world with brittle deformation affecting every life above and inside the ground... America certainly has their "fun" with ground-shaking especially on the Western coast. California is actually dubbed as "the Earthquakes State." Everybody is worried that one big earthquake will force California to crack and float away. What a silly notion! Earthquakes are not limited to Western states... New York and a good number of other Eastern states has been struck with earthquakes...
But what is even more intrigued is that the Mid-west states DO have earthquakes! You see, earthquakes are usually caused by plate boundaries shifting around on the thin layer of lithosphere... There is no fault (like San Andrea's Fault in Calif) in the Midwest for MILES. It is very unusual for earthquakes to occur in Mid-west. Although the earthquakes are infrequent but are known as "intraplate earthquakes".
Earthquakes under 4.0 magnitude are very minor and occur everyday and aren't felt by many people. Although, more severly damaging would be the "major earthquakes" which are 6.0 magitude or more. The most threatening earthquakes are known as "Great Earthquake" 8.0 magintuide or more. "Great earthquakes" are VERY RARE... averaging about 1.4 earthquake per year. Some years there are none, other times there are two or three.
Now I can move on to my point of this thread... New Madrid, Missouri in year 1811. I learned of this and thought about Patrick (cental34) who lives pretty close to this city... I thought this will be very interesting information for people to know!
The year 1811 to 1812 a quiet little city was suddenly awoken by a Great Earthquake (8.0 mg). Fortunately the town was sparsely populated and there weren't many structures so the damages didn't affect but nonetheless there were amazing eyewitness accounts that indicated of the ground "rolling over" and "dishes and silverware were being thrown up in the air"! Little did they know that they were describing the processes of several waves being released-- the P-waves, S-waves, and the most damaging L-waves. A loud sonic boom was heard from the waves as well! I am sure the USGS geologists would love to go back to that day in a time machine.
That was one big earthquake for the New Madridians...! So now they have satisfied the annual quota of a Great earthquake... but no, the Earth wasn't finished...! Within 52 days in New Madrid, after the first one, there were TWO more of Great Earthquakes striking the SAME city! Wait, are you telling me that there were THREE GREAT EARTHQUAKES IN TWO AND HALF MONTHS?! AND FROM THE SAME SITE?! Yes! This was an amazing geology historical moment where there were NO plate movements or volcanoic activty that caused those intraplate earthquakes!
Well, time flew by. People moved out westward. New Madridians have forgetten about this. USGS hasn't forgetten this-- they are now concerned about New Madrid. Well, I am sorry to inform you but if there is an earthquake in one site, it is bound to happen again... New Madrid had revealed that there were more of Great Earthquakes striking the city's proxmity long time before 1811 which gave the USGS an estimated average of Great Earthquakes for this little lonely town to be 200 to 500 years per Great Earthquake. Now do your math... 2005 minus 1911 equals 194 years... 194 years has passed by and the Earth's ground is VERY strained and stressed to snap... within next 300 years. the USGS is very concerned about New Madrid and the neighoring areas's building codes to be earthquake-resistant and prepare the citizens if an earthquake occurs.
Unforuntately, because of people's tendency to generalize things, nobody will think that Midwest will have a Great Earthquake because "it never happened in our lifetimes". Well New Madrid wasn't heavily populated in 1811, but there was a handful of people who witnessed this ... and if it happens again in the modern New Madrid with a population of 3,334 and the cities around like Memphis, TN (pop: 650,100) and St. Louis, Mo. (pop: 348,189) will suffer.
The aftermath of future earthquakes shows possible effects if an earthquake strikes New Madrid, Missiouri... The Roman numbers on the map refer to the scale of the epicenter of New Madrid to have serious damages of 8 (VIII), which damages are explained as "Drivers have trouble steering. Houses that are not bolted down might shift on their foundations. Tall structures such as towers and chimneys might twist and fall. Well-built buildings suffer slight damage. Poorly built structures suffer severe damage. Tree branches break. Hillsides might crack if the ground is wet. Water levels in wells might change", and reduces. as one goes further away from the epicenter of an earthquake, to a mildly damaging state of 4 (IV), which damages are described as "Most people indoors feel movement. Hanging objects swing. Dishes, windows, and doors rattle. The earthquake feels like a heavy truck hitting the walls. A few people outdoors may feel movement. Parked cars rock".
Now now I am not trying to cause a PANIC. I thought this is interesting and people should be aware that they are not immune to the Earthquakes. It happens EVERYWHERE and people needs to know how to protect themselves if it occurs.
This is the prefect "something" to tell at a party! A GREAT Ice-breaker! ;-)
Earthquakes fascinate me SO much, of course because I have experienced it (never major or great earthquakes, although and thank goodness!). If you got more questions about geology, ASK AWAY! I think if I suck at art, I definitely will be a geologist today.
****
If you want to see the earthquake activity of Midwestern states, go here: http://folkworm.ceri.memphis.edu/recenteqs/ you will be very surprised to see there are MANY activity...!
For more information...
http://www.seismo.unr.edu/ftp/pub/louie/class/100/mercalli.html "The Modified Mercalli Scale
of Earthquake Intensity"
Historical New Mardid Earthquake of 1811
http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html
http://hsv.com/genlintr/newmadrd/
Want to see the current world map of recent earthquakes, volcanic activity and many more?
http://hsv.com/scitech/earthsci/quake.htm
New Madrid, Missouri -- 1811
Earthquakes have plagued the world with brittle deformation affecting every life above and inside the ground... America certainly has their "fun" with ground-shaking especially on the Western coast. California is actually dubbed as "the Earthquakes State." Everybody is worried that one big earthquake will force California to crack and float away. What a silly notion! Earthquakes are not limited to Western states... New York and a good number of other Eastern states has been struck with earthquakes...
But what is even more intrigued is that the Mid-west states DO have earthquakes! You see, earthquakes are usually caused by plate boundaries shifting around on the thin layer of lithosphere... There is no fault (like San Andrea's Fault in Calif) in the Midwest for MILES. It is very unusual for earthquakes to occur in Mid-west. Although the earthquakes are infrequent but are known as "intraplate earthquakes".
Earthquakes under 4.0 magnitude are very minor and occur everyday and aren't felt by many people. Although, more severly damaging would be the "major earthquakes" which are 6.0 magitude or more. The most threatening earthquakes are known as "Great Earthquake" 8.0 magintuide or more. "Great earthquakes" are VERY RARE... averaging about 1.4 earthquake per year. Some years there are none, other times there are two or three.
Now I can move on to my point of this thread... New Madrid, Missouri in year 1811. I learned of this and thought about Patrick (cental34) who lives pretty close to this city... I thought this will be very interesting information for people to know!
The year 1811 to 1812 a quiet little city was suddenly awoken by a Great Earthquake (8.0 mg). Fortunately the town was sparsely populated and there weren't many structures so the damages didn't affect but nonetheless there were amazing eyewitness accounts that indicated of the ground "rolling over" and "dishes and silverware were being thrown up in the air"! Little did they know that they were describing the processes of several waves being released-- the P-waves, S-waves, and the most damaging L-waves. A loud sonic boom was heard from the waves as well! I am sure the USGS geologists would love to go back to that day in a time machine.
That was one big earthquake for the New Madridians...! So now they have satisfied the annual quota of a Great earthquake... but no, the Earth wasn't finished...! Within 52 days in New Madrid, after the first one, there were TWO more of Great Earthquakes striking the SAME city! Wait, are you telling me that there were THREE GREAT EARTHQUAKES IN TWO AND HALF MONTHS?! AND FROM THE SAME SITE?! Yes! This was an amazing geology historical moment where there were NO plate movements or volcanoic activty that caused those intraplate earthquakes!
Well, time flew by. People moved out westward. New Madridians have forgetten about this. USGS hasn't forgetten this-- they are now concerned about New Madrid. Well, I am sorry to inform you but if there is an earthquake in one site, it is bound to happen again... New Madrid had revealed that there were more of Great Earthquakes striking the city's proxmity long time before 1811 which gave the USGS an estimated average of Great Earthquakes for this little lonely town to be 200 to 500 years per Great Earthquake. Now do your math... 2005 minus 1911 equals 194 years... 194 years has passed by and the Earth's ground is VERY strained and stressed to snap... within next 300 years. the USGS is very concerned about New Madrid and the neighoring areas's building codes to be earthquake-resistant and prepare the citizens if an earthquake occurs.
Unforuntately, because of people's tendency to generalize things, nobody will think that Midwest will have a Great Earthquake because "it never happened in our lifetimes". Well New Madrid wasn't heavily populated in 1811, but there was a handful of people who witnessed this ... and if it happens again in the modern New Madrid with a population of 3,334 and the cities around like Memphis, TN (pop: 650,100) and St. Louis, Mo. (pop: 348,189) will suffer.
The aftermath of future earthquakes shows possible effects if an earthquake strikes New Madrid, Missiouri... The Roman numbers on the map refer to the scale of the epicenter of New Madrid to have serious damages of 8 (VIII), which damages are explained as "Drivers have trouble steering. Houses that are not bolted down might shift on their foundations. Tall structures such as towers and chimneys might twist and fall. Well-built buildings suffer slight damage. Poorly built structures suffer severe damage. Tree branches break. Hillsides might crack if the ground is wet. Water levels in wells might change", and reduces. as one goes further away from the epicenter of an earthquake, to a mildly damaging state of 4 (IV), which damages are described as "Most people indoors feel movement. Hanging objects swing. Dishes, windows, and doors rattle. The earthquake feels like a heavy truck hitting the walls. A few people outdoors may feel movement. Parked cars rock".
Now now I am not trying to cause a PANIC. I thought this is interesting and people should be aware that they are not immune to the Earthquakes. It happens EVERYWHERE and people needs to know how to protect themselves if it occurs.
This is the prefect "something" to tell at a party! A GREAT Ice-breaker! ;-)
Earthquakes fascinate me SO much, of course because I have experienced it (never major or great earthquakes, although and thank goodness!). If you got more questions about geology, ASK AWAY! I think if I suck at art, I definitely will be a geologist today. ****
If you want to see the earthquake activity of Midwestern states, go here: http://folkworm.ceri.memphis.edu/recenteqs/ you will be very surprised to see there are MANY activity...!
For more information...
http://www.seismo.unr.edu/ftp/pub/louie/class/100/mercalli.html "The Modified Mercalli Scale
of Earthquake Intensity"
Historical New Mardid Earthquake of 1811
http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html
http://hsv.com/genlintr/newmadrd/
Want to see the current world map of recent earthquakes, volcanic activity and many more?
http://hsv.com/scitech/earthsci/quake.htm
