Oregon State University oceanography researcher Bill Chadwick and his partner Scott Nooner of Columbia University were finishing up a research trip back on July 28th. They were about 250 miles west of the central Oregon coast when they decided to stop by one of their favorite investigative haunts, an undersea volcano called the Axial Seamount. They had learned a lot about its last eruption in 1998 and eventually conjured up a prediction that it would erupt again before 2014.
They had placed numerous earthquake and ground elevation change detection devices in anticipation of better pinpointing the exact time period of the seamount’s next big magma blow. But when they lowered their robotic research vehicle (Jason) to the side of the seamount, they couldn’t find some of their instruments. They were gone. And for good reason. The Axial Seamount had erupted on April 6th, within a time period predicted by Chadwick and Noonen.
Normally the two wouldn’t celebrate the loss of expensive equipment, some of which you can see covered in newly hardened lava on the side of the seamount. But in this case, it was probably worth it because their prediction of the eruption and the subsequent event proved that they were figuring out how the seamount operates.
In the top picture, Bill Chadwick stands beside Jason, the robotic observation vehicle aboard the R/V Atlantis, a ship operated by Harvard University’s Woods Hole Oceanographic Institution. The pictures below him show the hydrophones and earthquake detection and ground movement recording devices that were relaying data back to the surface. The bottom two pictures show the devices inundated and entombed by the advancing lava that shot out of the undersea volcano on April 6th.
Chadwick told NewsLincolnCounty.com that they had no inkling that the seamount had erupted. He said there had been a swarm of small earthquakes in early April but nothing to indicate that an eruption had occurred. They later learned that the devices were offline during the actual eruption. So they had to learn about their successful prediction the old fashioned way; going down and having a look through the eyes of Jason the robotic vehicle. It didn’t take them long to realize that their old dive site didn’t look the same because the eruption pushed everything around and added a lot more lava to the scenery.
Chadwick said it gave him great pleasure to realize that he and others had applied lessons learned from watching on-land volcanoes shake, rattle and blow. He said predicting Axial Seamount was a special opportunity because of its unique position in the ocean off Oregon. He says the seamount is anchored in a part of the ocean floor that is actually spreading apart. And as part of that ground moves farther east, it undercuts the North American plate that forms the Cascadia Subduction Zone, the one that is supposed to trigger a strong earthquake for Oregon and Northern California. Chadwick says Axial Seamount’s activities don’t appear to him to provide much of a cause-and-effect link on what to expect on the subduction zone. He says it’s all part of a larger whole, but how the pieces interact is hard to quantify.