mission
Back in the Water Again
Sunday, September 25, 2005Jo Dodds and Ben Larson
Daily Report
Jo Dodds, Science Teacher, ID
Waking up this morning, we could tell that the winds and swells were calmer as the cruise participants didn’t sway as much in bed and had much less difficulty moving around. After checking the data displayed in the computer room, wind speed was recorded at 22 knots…much better than the 29.9 knots yesterday. This was definitely a welcomed relief for everyone. There is still much science to do on the seafloor.
To start the day off, ABE was launched on the starboard side of the ship. Dana Yoerger, watches every launch and monitors ABE’s every move in the sea. The high resolution maps that are produced from ABE’s data are necessary for scientists to use their time more efficiently as they investigate the hydrothermal vent areas. With better maps to use, then scientists can use their time on the seafloor more efficiently. In the first part of ABE’s dive, it will finish mapping the Summit Seamount on the west ridge of the Endeavour Segment and then make passes along other unmapped segments in the Endeavour area. The lithium batteries on ABE will give enough power for approximately 12-13 hours. ABE will then go into a sleep mode while Jason II is working on the seafloor. ABE will be brought back either tomorrow or Tuesday, depending on the Jason II’s schedule.
After ABE went into the water and the ship was in the correct position, an elevator was sent to the seafloor off the starboard side of the ship approximately 1300 hr (1 pm). It carried a seismonument to be positioned at KESW (Keck Endeavour South West). The elevator is weighted so that it will go straight down to the seafloor and be available for Jason to easily find and retrieve instruments.
Following the release of the elevator, Medea and Jason were deployed at 1330 hr (1:30 pm). The seafloor in this area is 2370 meters deep. One of Jason’s main task tonight is to check the broadband seismometer for data. Jason will then travel 3 kilometers to place the seismonument. Four hours after Jason reached the bottom the pilots are still working to accomplish these tasks for the seismologists. It takes so much time to navigate, get in good position, and do the tasks that are on the dive plan. The skilled Jason crew knows how to get the job done correctly and trying to hurry anywhere on the seafloor only stirs up sediment. When sediment is disturbed, then nothing can be seen.
Along with having the ROV and AUV in the water, there is planning for nine scientists to leave this leg of the research crew and ten new scientists to come on board for the remaining cruise. This transfer will occur late Monday night and involves another ship coming out to where our ship, the Thompson, is. Since we are out approximately 200 miles off the coast of Vancouver Island, the Arctic fishing ship, Frosty, will take over 24 hours to get to us. Frosty is coming to the Thompson so that we don’t loose any more time than necessary with the ROV dives. So much to do and only limited time to accomplish it!
Impressions
Ben Larson, Graduate Student, University of Washington School of Oceanography
Here’s the job, can you get it done?
The interface between the ocean and the earth’s interior is not a very hospitable place. It’s very deep, it’s very hot, and it’s usually far removed from land. The collection and analysis of hot vent fluids is a dicey proposition to begin with, and if you want to measure the chemical properties of the fluids in-situ, then the obstacles rise up faster than buoyant fluid from a vent chimney. You’re out in the middle of the ocean with only the stuff you brought and whatever you can swipe from your neighbor when he’s not looking. What’s more, since most companies doesn’t sell commercial in-situ vent fluid analyzers, most equipment is home spun and requires lots of love and attention, and damage to even the smallest part of that equipment can mean the difference between a year’s worth of data and a year’s worth of time to contemplate your mistakes. In an environment like this, you make do with what you’ve got, and the problem solving ranges from the innovative to the bizarre. When the creative juices are flowing so freely, the results are unpredictable. So when somebody suggested that for my impression, I could do an ode to duct tape, my mind started working. The result is this cross between Dr. Seuss and Bill Nye. I’ve been told I shouldn’t quit my day job. Enjoy…
But build up my sensors and make them read true.
For this kind of work, I’ve got tools of all kind,
Some nice and normal, some boggle the mind.
Suppliers of power and cables that chat.
There’s tin snips and test clips and drill bits galore,
Connectors, dissectors and meters and more.
And this guck for my o-rings, it’s some kind of lube.
There’s lithium batteries and green circuit boards,
A funnel in case something needs to be poured.
Excedrin for the occasional pain in my cranium.
There’s ICL cones and orange spiral wrap,
And computers so small, they fit on your lap.
All manner of screws and a spiffy torque wrench. ,
There’s plastic zip ties for keeping things neat,
And fiberglass sleeving, at least 90 feet.
And molecular sieves for water mishaps.
There’s sensors for chloride, $3,000 a shot,
Sometimes they work…sometimes not.
Yet I can’t help but feel there’s something I’ve missed.
Ah, silly me, That’s it! But of course!
More useful than code by a fella named Morse!
More than a few times, it’s rescued my hiney.
The sound when it’s peeled makes you jump off your seat,
And the scent that arises, oh what a treat!
From deep ocean vents to those talkative faces,
Man’s best idea since he came from the ape,
Where would I be without my roll of duct tape.
Daily Question
Midge Yergen , Science Teacher, West Valley Middle School, Yakima, WA
Hi Midge.
So far on this cruise, 3 short period and one broad band seismometers were pulled out at Nootka and 1 broadband seismometer was pulled out at the Explorer Plate. If weather permits, 7 short period and 1 broad band seismometer will be pulled out at the Endeavour segment to replace batteries and check to make sure the data logging is working. Then they will be placed back in the same spot.
Yes, the glass beads are still being used for the broadband seismometers. The seismologists use these small beads to back fill the area in which the seismometer is buried so the sediment won’t settle on top of the seismometer and the seismometer is in a very stable environment. Seismologists are hoping that they won’t have to replace the beads at the Endeavour site to save time.
The data is good, but many months of work will be needed before this year’s data can be analyzed. The SOSUS (Sound Surveillance System) website (http://www.pmel.noaa.gov/vents/acoustics/seismicity/seismicity.html) has quite a few earthquakes for the Endeavour Segment area that are magnitude 2.5 or greater. The data for the Endeavour segment that was collected will have recorded events with magnitudes lower than 3 and should be at least ten times the amount recorded by SOSUS.
Since you sailed with this same group in 2003, you’ll be interested to find out that the seismometers deployed between August 2003 and August 2004 recorded 12, 792 earthquakes on the Endeavour Segment. Out of this amount, 2, 000 earthquakes have been thoroughly analyzed since the recovery of the instruments from the seafloor by a small army of students. Analysis will continue for many years.
Drew Matheny, Tolt Middle School, Carnation, WA
The area that is being studied at the Endeavour Segment of the Juan de Fuca Plate is approximately 2200 meters deep. It takes an hour to an hour and fifteen minutes for the elevator to surface. No organism that has come to the surface has exploded. The reason is that there are no gas or air inside the body and tissues of these animals. It is gases that expand as the pressure decreases when the animals are moved fr4om the deep seafloor toward the surface.
