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State Geology Experts Warn of Earthquake Dangers

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The Obama administration continues to ignore the danger of follow-up catastrophes in the Rim of Fire, but pockets of experts in California, Oregon, and Alaska, where the most massive earthquake ever recorded in North America occurred in 1964, are seriously concerned. At the same time, many officials report that the U.S. is not prepared.

On March 24, the Homer Tribune in Alaska (Homer is a coastal location southwest of Anchorage) published a lead editorial called, "Alaska is Earthquake Central," saying, "On any given day, more than one tremor registers somewhere in the state. The tragedy unfolding in Japan after its 8.9 magnitude quake offers a chance for all of us to take stock of supplies, preparedness, plans in place and skills in hand.

"Perhaps the most important reminder of all is the sobering list of facts released by the Alaska Earthquake Information Center at the University of Alaska Fairbanks Geophysical Institute. A big rattle devastating eonugh to cause major harm is not a question of if, but when (emphasis added):

"Great earthquakes (larger than magnitude 8) have rocked the state on an average of once every 13 years since 1900. It is only a matter of time before another major earthquake will impact a large number of Alaskans. The Alaska Seismic Hazards Safety Commission that is part of the office of the governor, included the following information in their report, "Earthquake Risk in Alaska, June 4, 2010": Alaska has had 11 percent of the world’s recorded earthquakes; three of the eight largest earthquakes in the world were in Alaska; teven of the ten largest earthquakes in the United States since 1900 were in Alaska; Alaska has had an average of:

"One great earthquake (magnitude 8 or larger) earthquake every 13 years;

"One magnitude 7 to 8 earthquake every year;

"Six magnitude 6 to 7 earthquakes per year;

"Forty five magnitude 5 to 6 earthquakes per year;

"Some 320 magnitude 4 to 5 earthquakes per year;

"An average of 1,000 earthquakes are located in Alaska each month."

In California, Costas Synolakis, director of the Tsunami Research Center at University of Southern California, is quoted in the Chinese People’s Daily, warning that Southern California could be hit with "localized" tsunamis up to 40 feet high, caused by underwater landslides, even though the area is not considered high risk for tsunamis. People’ Daily also notes that Southern California "has no tsunami measuring instruments off its coast," because it is not a high-risk area, according to the LA Times. California State Geologist John Parrish also warned that "Mother Nature is notorious for not obeying rules that we make," referring to the mistaken confidence that events like the earthquake and tsunami in Japan only occur every 2,000 to 3,000 years. In the last 72 hours, the U.S. Geological Survey’s earthquake watch reported 5 Alaska earthquakes and 2 California earthquakes with a magnitude over 3.

But despite this, and much more information about earthquake activity and dangers, on March 23, the California Emergency Management Agency in cooperation with the National Weather Service cancelled the Live Code Warning exercise that was scheduled. The decision was made in Del Norte, Humboldt, and Mendocino counties to cancel the live tests of sirens, 911, and similar systems, and instead, only hold "Tsunami Awareness" community meetings. In Santa Cruz, however, the local population was much more serious, having experienced direct effects of the Japan tsunami, and the Santa Cruz News played up the forecast by retired USGS geologist Jim Berkland that there is an immediate danger of earthquakes in California in late March.

In Oregon, a report entitled "Cascadia Subduction Zone Earthquakes: A Magnitude 9.0 Earthquake Scenario," has been put out by a consortium called the Cascadia Region Earthquake Workgroup (CREW), which includes members from Boeing, the Army Corps of Engineers, the Oregon business community, and the U.S. Geological Survey.

The introduction to the report states:

"When a magnitude (M) 8 to 9 subduction earthquake occurs, it will cause many fatalities and much damage unless we prepare for it. These quakes have occurred anywhere from 200 to 1,000 years apart, with an average of 500 years between them. Our last one was on January 26, 1700. We can look to the 2004 Sumatra and 1964 Alaska earthquakes and tsunamis for some guidance as to what to expect.

"Groundshaking, landslides, liquefaction, tsunamis, fires, hazardous material spills, and building damage are some of the hazards we face from a Cascadia subduction zone earthquake. The ground could shake for four minutes, even more in some places. This will create unprecedented damage and potentially thousands of casualties."