Brief port call between mooring deployments

After the complicated deployment of a two-legged mooring at the Axial Base site, the Thompson headed east for a 24-hour steam to Newport, Oregon. The weather was fair, with a modest following swell wave, a gentle transit for those prone to seasickness. Newport is a city of about 10,000, situated at the mouth of the Yaquina River, 130 miles south of Portland. It hosts a large fishing community and there is continuous traffic of both sport and commercial fishing boats entering and exiting Yaquina Bay. On the way in we passed an old-fashioned wooden trolling boat that had its long polls down and was heading out to the fishing grounds off shore. We approached Newport just after low tide when the current runs slowly. Between tides, the current is strong and the transit through the channel is treacherous. Seals greeted us from their perch atop a channel buoy as we passed by.

As we approached the NOAA facility we could see trucks, equipment and a large crane waiting for us on the dock. Loading began as soon as we tied up. The first to come aboard were stacks of steel plates weighing 6000 pounds per stack. These are heavy enough that the ship’s stability and balance must be considered in planning their arrangement on deck. Baskets full of orange “football” floats came next and then a large, nine-foot tall platform made of syntactic foam, which can withstand tremendous pressure and still retain its buoyancy, was craned aboard. These are all pieces of the next mooring that will be deployed, another two-legged mooring like the one that was just put down near Axial Volcano. This one will be placed at the base of the continental slope off the Oregon coast in 2900 meters of water, 300 meters deeper than the Axial mooring. At this water depth, a lot of flotation is needed just to hold up the cables and chains of the mooring, and two massive anchors, 12000 pounds each, are needed to keep the whole arrangement fixed to the seafloor.

On Wednesday Oregon State University loaded gear that will be used at the relatively shallow, 80-meter study site, nine miles off the coast on the continental shelf. This includes a special instrument that uses sonar to detect zooplankton in the water column. The site will have its own challenges, including strong tidal currents, turbid water and a shallow depth that is makes it more difficult for ROV operations.

This leg of the cruise is not over yet. A storm is forecast for next week and we intend to get as much done as we can before it arrives.