With new research predicting a significant chance of a massive, tsunami-generating earthquake off the Oregon coast in the next 50 years, Pat Corcoran finds his services in more urgent demand than ever.
Corcoran, coastal hazards specialist for Oregon Sea Grant Extension, is a one-man roadshow, taking the message of tsunami and earthquake preparedness to community meetings and workshops up and down the coast.
Corcoran’s message isn’t complicated. He says lives can be saved if coastal residents and visitors are aware of just three things:
- what to do when you feel an earthquake on the coast
- where the high ground is wherever you are, and how to get there
- how to reconnect with loved ones once the event is over
Until recently, scientists thought the undersea faults off Oregon were subject to rupture every 500 years or so. But recent research by Chris Goldfinger of the Oregon State University marine geology and geophysics program suggests the cycle is more like every 240 years at the southern end of the fault. Given that the last tsunami-generating quake to hit the Oregon coast occurred in 1700, we’re overdue. Goldfinger predicts that there is a 37 percent chance of a tsunami-generating quake within the next 50 years.
Megathrust earthquakes occur in subduction zones—like the one just off the Oregon coast—at the boundaries where one tectonic plate is forced under another. Such quakes are among the world’s strongest, with magnitudes measuring up to magnitude 9. These earthquakes are identical to the quakes that rocked the Indian Ocean in 2004, Chile in 2010, and Japan in 2011. The resulting tsunamis killed a staggering 230,000 in the Indian Ocean region, hundreds in Chile, and thousands in Japan.
Corcoran has been working on coastal tsunami preparedness since 2005. With colleagues from the Department of Geology and Mineral Industries, the Oregon Office of Emergency Management, and the National Weather Service, he conducts “Tsunami Roadshows” along the Oregon coast, visiting dozens of communities each year.
- Read the whole story: printable .pdf | plain text
- Pat Corcoran's coastal hazards Web page at Clatsop County Extension
- Learn about Sea Grant's coastal hazards education and public engagement efforts
- Video: Three Things You Need to Know