Study: Risk Of Damaging Earthquakes Extends Even To Eastern Oregon, Washington
A new study from the U.S. Geological Survey shows that nearly half of all Americans live in areas that could experience damaging earthquakes.
Western Oregon and Washington face higher risk for a devastating earthquake. But the study shows even the eastern regions of both states could experience damaging shaking from a quake.
"The highest hazard is really along the western coast of the United States," said Mark Petersen with the USGS, who is one of the coauthors of the study. "The hazard is high along the coast, due mostly to the subduction zone. But there are also some faults that are inland and some faults off-shore that also can cause earthquakes."
More than 1.4 million people in Oregon and 5 million people in Washington are at risk from damaging earthquake shaking, according to the study.
The study updates risk assessments that relied on older geological models, and factors in recent population growth.
Seismologists look at the potential for damage by assessing g-force — basically measuring the amount of ground shaking during an earthquake. Petersen explains that an earthquake with 0.1 g-force presents relatively little risk of damage. But in Oregon and Washington, more than 6.4 million people live in areas with a potential of 0.4 g-force.
"Usually we start getting damage above .2 g-force, said Petersen. "So 0.4 G is pretty significant."
"There is some potential for almost everyone in Oregon to experience damaging ground shaking levels in a 50 year period," said Petersen. "If you live in these areas, you should take precautions."
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