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To: tcrlaf

Stunning.
Has any quake in recorded history resulted in such a massive land shift?


4 posted on 03/19/2011 7:21:18 AM PDT by mylife (Opinions: $1.00 ~ Halfbaked: 50c)
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To: mylife

The New Madrid?


6 posted on 03/19/2011 7:48:19 AM PDT by EBH ( Whether you eat your bread or see it vanish into a looter's stomach, is an absolute.)
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To: mylife

There was the earthquake during the early 1800s in the midwest that changed the course of the Mississippi River and landscape.


7 posted on 03/19/2011 7:49:36 AM PDT by grcuster
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To: mylife

The 1964 Alaska earthquake, also known as the Great Alaskan Earthquake, the Portage Earthquake and the Good Friday Earthquake. Lasting nearly four minutes, it was the most powerful recorded earthquake in U.S. and North American history, and the second most powerful ever measured by seismograph. It had a magnitude of 9.2, at the time making it the second largest earthquake in recorded history.

The powerful earthquake produced earthquake liquefaction in the region. Ground fissures and failures caused major structural damage in several communities, much damage to property and several landslides. Anchorage sustained great destruction or damage to many inadequately engineered houses, buildings, and infrastructure (paved streets, sidewalks, water and sewer mains, electrical systems, and other man-made equipment), particularly in the several landslide zones along Knik Arm. Two hundred miles southwest, some areas near Kodiak were permanently raised by 30 feet (9.1 m). Southeast of Anchorage, areas around the head of Turnagain Arm near Girdwood and Portage dropped as much as 8 feet (2.4 m), requiring reconstruction and fill to raise the Seward Highway above the new high tide mark.


9 posted on 03/19/2011 8:36:57 AM PDT by thackney (life is fragile, handle with prayer (biblein90days.org))
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To: mylife

Middleton Island has repeatedly experienced earthquake-induced uplift, with 5 terraces visible from the last 800 years. The plateau on the right side of this picture is the original beach. The vertical uplift due to the 1964 earthquake was 3.6 meters.

http://www.aeic.alaska.edu/quakes/Alaska_1964_earthquake.html

10 posted on 03/19/2011 8:39:56 AM PDT by thackney (life is fragile, handle with prayer (biblein90days.org))
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To: mylife

Last link, this one had more detail on land movement for 1964.

The initial seismic waves from the Good Friday Earthquake were so powerful that buildings as far away as Seattle, Washington swayed. The ground in Houston, Texas, was briefly lifted by four inches (10 cm), and lifted by as much as 2.5 inches (6 cm) in Florida. For two weeks, the entire planet vibrated like a giant gong as the seismic waves cirlced the globe.

This quake altered more of the earth’s crust than any other earthquake on record. More than 25,000 square miles (40,233 square km) of land north and west of the fault had shifted to the southeast. Much of this land dropped between 2.5 and 7.5 feet (.75 and 2.3 meters). Much of the ground south and east of the fault had lifted an average of six feet (1.8 meters), with the maximum being 38 feet (11.6 meters) at Montague Island. Undersea ground in a line from Ninchinbrook Island to the Trinity Islands—parallel to the faultline—lifted as much as 50 feet (15.2 meters). This is what caused the tsunamis that devestated Valdez, Seward, Kodiak, and many other towns. Anchorage shifted laterally six feet (1.8 meters), Valdez 33 feet (10 meters), and Seward 47 feet (14.3 meters).

For three days after the quake, almost 300 aftershocks shook Southcentral Alaska. Eighteen months passed before the aftershocks finally ceased, which numbered more than 10,000.

http://www.greatlandofalaska.com/reference/GoodFridayQuake.html


11 posted on 03/19/2011 8:44:24 AM PDT by thackney (life is fragile, handle with prayer (biblein90days.org))
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