The long trip north


Preparing to lower a basket with GEOMAR OBS
acoustics to 2000 m water depth for testing

It is a long, LONG way from Honolulu to our study area in the Emperor Seamount Chain – 2500 miles (4000 km). It’s about the distance of a coast-to-coast drive across the United States.   Ships travel much slower than cars – we have been averaging 9 nautical miles per hour, which is 10.5 mph. So it will take us at least 9 days of steaming around the clock to reach the field area.  The science party and science technical staff have been using the time required for this long journey to test and prep equipment that will be used during the study and to share our science with each other through talks, lectures and discussions. 

Valeria describes her research on the Nazca Ridge
(while bracing herself from ship motion!)
During the transit, the ocean bottom seismic teams from GEOMAR and WHOI have been testing each component of the equipment. On Thursday, they tested the acoustic units that we use to communicate with the instruments when they are on the seafloor; they lowered two batches of these units to 2000 m below the sea surface, and made sure that we could communicate with each of them. On Friday they tested the sensors that actually detect arriving seismic waves.  We definitely want to make sure everything works before we drop it off the side of the ship to sink over 6 km to the seafloor!  Today the OBS team will begin to assemble each OBS so that its ready to be deployed when we arrive.

We have also had tons of talks. Our science party works on a large range of cool science problems using different methods in field areas all over the world: Gulf of Mexico, Nazca Ridge, Lord Howe Rise, and Galicia Bank just to name a few. Tony, Robert and I have also been giving overview talks on the scientific objectives of the cruise and the methods that we can use to study them.

Slightly ominous sunset
Finally, the long transit provides plenty of time to get our sea legs – the North Pacific is not known to be particularly calm, and the last 24 hours has offered a taste of choppier conditions.  But it’s also given us time to take in some sunsets…

Donna Shillington
LDEO




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