ON THE PACIFIC, Day 3: A big fish-ing expedition

From June 25 to July 9, UO senior physics instructor Dean Livelybrooks and a team of national scientists on board the Atlantis research vessel will recover earthquake-monitoring equipment in the Pacific Ocean. Follow tweets and other activity at @uocas and #uoshiptrip. Visit explorationnow.org/atlantis to follow the action live. To read previous dispatches from the Atlantis, visit http://around.uoregon.edu/cascadia-initiative.

This humpback whale breached on the afternoon of June 27, much to the excitement of us onlookers.

It seems fitting, given this research mission is essentially about hooking some very big – and somewhat elusive – creatures.

Under the Cascadia Initiative, supervised by UO geophysicist Doug Toomey, dozens of seismometers – each about the size of a bathroom garbage can – have been planted on the ocean floor off the Northwest coast, to measure vibrations of tectonic plates. This data will ultimately give scientists a better picture of what a major earthquake could do to the region.

Some of the seismometers are housed in heavy-metal shields called “trawl-resistant mounts,” which protect them from fishing nets. These devices weigh 1,500 to 1,800 pounds each.

After scientists have located one of the seismometers using the remotely operated vehicle called “Jason,” the fishing begins: The device must be hooked and pulled to the surface.

On June 27, the team “hooked” a seismometer off the coast near Waldport. It was roughly a half-mile down.

What followed was a process familiar to anybody who fishes for big fish: Using a crane and a winch, the ship crew slowly pulled the device up. At times, the crane let out a little line, easing the tension; then, it would reel it all back in and then some, slowly bringing the device to the surface.

Let a little line out, take a little more back in. Repeat. This continued for nearly three hours.

Eventually, the crew won the day – its prize, a 1,500-pound device-with-seismometer lying on the deck.

A whale of a catch, so to speak. And for the scientists at least, just as exciting as seeing the real thing.

- by Matt Cooper, UO Office of Strategic Communications