January 14th, 2013-
Portland, Oregon- New research is giving us some insight into when a major earthquake could strike the Northwest. The research was done in part by Stanford geophysics Professor Paul Segall. He has been tracking a series of very small tremors that rumble deep within the earth. The slow tremors happen roughly every summer along the Cascadia Subduction Zone, an undersea fault about 70 miles off the Oregon Coast. Over the last decade, data shows the tremors have been getting progressively bigger. Last summer, the Pacific Northwest experienced a notably large one. Experts believe those tremors are adding stress to the offshore fault. Using this data, Segall built a computer model which suggests it will be one of those tiny quakes that triggers a major magnitude 9 earthquake. “What we do see is that ultimately one of these tends to develop into a fast and potentially, damaging earthquake,” said Segall. Segall said that scientists don’t yet know how big those tremors need to get before they explode into a mega-thrust quake. And that means a major earthquake in the Pacific Northwest could still be hundreds of years away. But, he added, those tiny tremors are a good reminder that we always need to be prepared. Scientists discover the largest-known spiral galaxy. –King 5
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Cascadia quakes of magnitude 8+ and 9+ over the last 6000 years.