Earthquake anyone?

[garyd]

New Madrid Earthquake was one of the most powerful ever recorded. The Missippi River according to some eye witnesse ran backwards for three days.

I remember reading that there are several thousand earthquales every day not counting those of volcanic origin most however are less than two on the richter scale.

 

[Old Rocks]

Are you guys watching that volcano in Alaska? Big potential for an earthquake there..

Ummmm...... Do you mean from the volcano, or Alaska in general? Volcanos ussually do not produce big quakes, that is, greater than 6.5. However, the Alaskan subduction zone definately produces some whoppers. 9+.

 

[RodISHI]

I read the account of it and saw a lot of the pictures from back then. The Missouri River also changed course from that quake if I recall properly.

 

[garyd]

Pictures??? From 1812?

 

[Old Rocks]

Are you guys watching that volcano in Alaska? Big potential for an earthquake there..

Same fault line. California, Oregon, Washington, and Alaska share that fault line. If there was a major shift all our volcanoes will go, possibly even all at once. Or on the reverse, if they all went at the same time there would be a major shift. It's the root of the "big one" that people fear on this coast.

No, they do not share the same fault line. Not even the same plate causes the subduction zones. The San Andreas is a slip-strike fault between the North American Plate and the Pacific Plate. The subduction zone that causes the huge quakes from Cape Mendecino to Vancouver Island is the Cascadia Subduction Zone, where the Juan de Fuca plate subducts beneath Northern California, Oregon, Washington, and Southern British Columbia. The quakes in Alaska are caused by the Pacific Plate subducting beneath Alaska.
Geodynamics - Observing the Cascadia Subduction Zone in action

 

[RodISHI]

1895 Plates are what they are called.

Here are some at this link from the 1895 Tuscany, Italy Earthquake.

You can probably find more online.

 

[garyd]

New Madird was in Missouri in 1812.

 

[RodISHI]

Yup and there are plates/pictures accounted for of some of the damage done. I am sure if you are interested you can find them.


In 1880, George Eastman, set up the Eastman Dry Plate Company in Rochester, New York.

 

[garyd]

Did he invent a time machine too? That would have been Nearly eighty years priot to 1885.

 

[Luissa]

Did he invent a time machine too? That would have been Nearly eighty years priot to 1885.

probably talking about pictures take after the fact! Here is some good ones I found taken in 1904!

Historic Earthquakes

 

[RodISHI]

I think garyd has a bone to pick about historical pictures and records or maybe he just wants a history lesson on imaging.


Affected trees tilted from the New Madrid earthquake, taken in Tennessee

Take this one up with the USGS, New Madrid Earthquakes 1811-1812 Images

 

[RodISHI]

Largest earthquakes in the history of North America.

#1 Magnitude 9.2 1964 03 28 Prince William Sound, Alaska
#2 9 1700 01 26 Cascadia subduction zone Cascadia, a region 600 miles long that includes northern California, Oregon, Washington, and southern British Columbia.

#3 8.7 1965 02 04 Rat Islands, Alaska

#4 8.6 1957 03 09 Andreanof Islands, Alaska

#5 8.2 1938 11 10 East of Shumagin Islands, Alaska

#6 8.1 1946 04 01 Unimak Islands, Alaska

#7 8.1 1811 12 16 New Madrid, Missouri

#8 8.0 1899 09 10 Yakutat Bay, Alaska

#9 ˜8 1812 02 07 New Madrid, Missouri


2002 11 03 Denali Fault, Alaska

#14 7.9 1868 04 03 Ka'u District, Island of Hawaii

#18 7.8 1906 04 18 San Francisco, California

More at USGS

7.3 1959 08 18 Hebgen Lake, Montana
This earthquake caused 28 fatalities and about $11 million in damage to highways and timber. It is characterized by extensive fault scarps, subsidence and uplift, a massive landslide, and a seiche in Hebgen Lake. A maximum MM intensity X was assigned to the fault scarps in the epicentral area. The instrumental epicenter lies within the region of surface faulting. Area of perceptibility, maximum intensity, and Richter magnitude all were larger for this earthquake than for any earlier earthquake on record in Montana (from May 1869).

"Geological evidence indicates that 13 great earthquakes have occurred in the last 6000 years."

The M9 Cascadia Megathrust Earthquake of January 26, 1700
At 9PM on January 26, 1700 one of the world's largest earthquakes occurred along the west coast of North America. The undersea Cascadia thrust fault ruptured along a 1000 km length, from mid Vancouver Island to northern California in a great earthquake, producing tremendous shaking and a huge tsunami that swept across the Pacific. The Cascadia fault is the boundary between two of the Earth's tectonic plates: the smaller offshore Juan de Fuca plate that is sliding under the much larger North American plate.......... The earthquake shaking collapsed houses of the Cowichan people on Vancouver Island and caused numerous landslides. The shaking was so violent that people could not stand and so prolonged that it made them sick. On the west coast of Vancouver Island, the tsunami completely destroyed the winter village of the Pachena Bay people with no survivors. These events are recorded in the oral traditions of the First Nations people on Vancouver Island. The tsunami swept across the Pacific also causing destruction along the Pacific coast of Japan. It is the accurate descriptions of the tsunami and the accurate time keeping by the Japanese that allows us to confidently know the size and exact time of this great earthquake.