Underwater volcano active off Oregon coast

A volcano may be erupting off the Oregon coast, scientists say

Three hundred miles off the Pacific Northwest coast, the seafloor has been rumbling.

Over the past five months, there were hundreds of small earthquakes on most days at Axial Seamount.

Then on April 24, there was a spike: nearly 8,000 earthquakes. The seafloor level dropped more than two meters. Temperatures rose.

Scientists believe an underwater volcano is erupting.

An eruption is not a threat to coastal residents, researchers say, because the earthquakes are small, mostly magnitude 1 or 2, and the seafloor movements are relatively gradual, so they won't cause a tsunami.

The volcanic activity has no relationship to the Cascadia Subduction Zone, which scientists watch closely for signs of a much larger and more destructive earthquake.

To Bill Chadwick, an Oregon State University geologist, the eruption at Axial Seamount was not a surprise.

He had predicted it would happen this year. He predicted the previous eruption, in 2011, too.

Chadwick hopes the lessons he and his collaborator, Scott Nooner at the University of North Carolina Wilmington, learn from Axial Seamount can eventually be applied to volcanoes on land.

Land volcanoes have thicker crusts and are influenced by large earthquakes and other nearby volcanoes, among other things, so predictions are more difficult, Chadwick said.

"Axial Seamount is a pure example, if you will," he said. "It has relatively simple plumbing."

Chadwick and other scientists watch the signals at Axial Seamount in real-time via a cable laid out on the seafloor. The cable is part of the Ocean Observatories Initiative funded by the National Science Foundation. [...]

I doubt that it has nothing to do with the Cascadia Subduction Zone, since it is practically right on top of it. I presume they mean to say, that the volcano isn't signaling an imminent earthquake. As far as they can tell.

Read the whole thing for embedded links, photos and more.

     

Japanese Tsunami Debris on Oregon Coast

It's starting to arrive in greater quantities. A few Sunday's ago, I encountered my first piece. We were having a nice walk on a local beach:


It was another day in paradise. Just beautiful. Then I saw it:



A first I thought it was just an ordinary piece of rubbish. But then I saw the Japanese writing on it. It was a bottle of hairspray. It had floated in the ocean for a long time, so long that it had seaweed growing on it.

I could only wonder; had it been sitting on a shelf in a hair salon? Or on a ladies dressing table, or in someone's bathroom cabinet? Was it swept out to sea from someone's house - WITH the house? With people still in the house? All questions that can never be answered.



I left it there, bearing witness to a disaster far away, years ago. I continued my walk, and told myself I would pick it up on my way back down the beach. But on the way back, it was gone. Either someone else picked it up, or it went back to sea for a while, to remind someone else on another day.

Meanwhile, an article in the Vancouver Sun tells us that a Tsunami here would not be as bad as the earthquake that would cause it:

Monster earthquake would devastate Pacific Northwest, leaving thousands dead
But tsunami would be secondary issue for Lower Mainland, because Vancouver Island would take brunt of big wave: expert

A monster earthquake and tsunami would wreak havoc on B.C.’s west coast, but the effects would be far worse in Washington and Oregon states.

“I suspect there’d be a significant number of deaths in the Lower Mainland as a result of the shaking,” said Ronald Clowes, a crustal seismologist and professor emeritus at the University of B.C. “But the tsunami would be a secondary concern.”

Clowes spoke on Friday after researchers told Oregon legislators Thursday that more than 10,000 people could die when — not if — a monster earthquake and tsunami occur off the Pacific Northwest coast.

Coastal towns would be inundated; schools, buildings and bridges would collapse; and economic damage could hit $32 billion, the researchers said.

These findings were published in a chilling new report by the Oregon Seismic Safety Policy Advisory Commission, a group of more than 150 volunteer experts.

[...]

According to the Oregon report, the 2011 Japan quake and tsunami were a wake-up call for the Pacific Northwest. Governments have been taking a closer look at whether the region is prepared for something similar, and discovering it is not.

Oregon legislators requested the study so they could better inform themselves about what needs to be done to prepare and recover from such a giant natural disaster.

The report says that geologically, Oregon and Japan are mirror images. Despite the devastation in Japan, that country was more prepared than Oregon because it had spent billions on technology to reduce the damage, the report said.

Meanwhile, a third minor earthquake has struck off the north B.C. coast, the latest in a series that has rattled the area since last fall. [...]

I don't deny that there is a seismic hazard here. But I don't know how they can say "Oregon and Japan are mirror images". Japan has a long history of active earthquakes, which is why they are better prepared. Earthquakes in Oregon are few and far between, which is why we are not better prepared. I don't see how that makes us a "mirror image". Though I suppose if a large earthquake and resulting tsunami happen, it won't much matter what we call it.