Cheryl Greengroves’ Insights

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Today we transited most of the day and arrived at Axial base (2600 m deep) after lunch where we did a full water column profile using a CTD (Conductivity, Temperature, Depth).  The CTD also has sensors to measure dissolved oxygen (DO), fluorescence (chlorophyll) and transmissivity (how much stuff is in the water – could be phytoplankton or other particulates).  The CTD is mounted on a frame called a rosette along with 24 Niskin bottles that allow us to take water samples anywhere in the water column. The instrument is connected to the ship via a conducting cable so we can see the data live on a computer in the lab and decide where in the water column we want to take our samples.  Once a spot is chosen, we send a signal down the wire to close a bottle and get a water sample. Once the rosette is back on deck, we can take multiple samples out of each 10 L Niskin bottle to do a variety of analyses in the lab. At this station, we collected water samples for DO, chlorophyll, DIC (dissolve inorganic carbon), salinity and nutrients to be run later. We also put the styrofoam cups we painted in a net bag attached to the CTD frame and sent them down to be shrunk.

After getting our CTD profile, the ship headed to Axial Caldera at the summit of the volcano (about 1500 m deep).  While enroute, the crew barbequed big slabs of steak for Sunday dinner – which was delicious! We also had an incredible sunset – the first of the cruise. But along with our sunny weather today came some lumpy seas which made it difficult to work and put a number of people out of commission.

This evening we are making our first dive on Axial Summit in the “ASHES” area to change out the HD camera (CAMHDA301) and an Osmotic Water Sampler (OSMOIA301).  It is amazing to see the smoking vents and tube worms live. To check the camera position they are going to plug it in, send pictures to shore via the undersea cable which will then send them to us via satellite so we can see them and adjust the camera. So even though we are only 1.5 km away, the signal will have traveled 1000’s of km to get to us. Crazy!

August 11-12, 2017

Day 3 – This is the last day I am wearing my seasickness patch. Hopefully I have my sea legs by now. Last night the ship re-located to the South Hydrate Ridge site which is at about 880 m deep.  Weather continues to be calm and the ship rides well.  Right after breakfast, my roommate (Hanis Zulmuthi – who is a UW freshman from Malaysia and terrific!) and I tried on our gumby survival suits (see our pictures on the website). We laughed so hard we had trouble getting our suits off. 

During the night the science team deployed and recovered the mass spectrometer. I still can’t believe they put these on the seafloor. They are finicky to get to work on land, much less 100’s of meters deep in the ocean.  When my partner (Julie Nelson) and I came on watch in the control van, we were still at the South Hydrate Ridge site and we were in the process of changing out a 3D velocity sensor, a Seabird pressure sensor and a digital camera. This was Jason’s 1000th dive.  After watch, I assisted Theresa Whorley, a UW graduate student, in doing the final set up on a pair of sediment pore water flux instruments called FLOBN-MOSQUITOS (Multiple Orifice Sampler and Quantitative Injection Tracer). They suck up samples using an osmotic pump through long titanium needles pushed into the sea floor. This is a standalone unit that will be out for a year and not hooked to the cable. In addition to this flux instrument, we exchanged two other standalone flux measurement instruments at the South Hydrate Ridge site, the FLOBN-CAT (Chemical Aqueous Transport Flow Meter) and the OSMAOIA 101 (Osmotic Water Sampler).  These are located near Einstein’s Grotto, along with the mass spec and a digital camera, which is a couple 100 meters from where we put the 3D velocity meter and pressure sensor. The flow sensors did not get installed on the seafloor until the wee hours in the morning – so Theresa had a long night. Earlier in the evening, two of the students, Zach Cooper and Michelle Lee, went fishing for pyrosomes with a long net (see picture).  Their nick name is “pickles” and we have seen quite a few of these on our dives.  The students preserved three specimens in the freezer to bring home.

Day 4 – Today we moved over to the Slope Base site which is 2900 m deep which means it takes Jason a couple hours to travel each way (at an average of 25 m/min).  At this site we threw one of the inverted echo sounders off the fantail and let it freefall to the seafloor (This was planned).  Jason then went down and relocated it, unplugged the old one, plugged in new one and brought the old one to the surface. Now we are on our way to Axial Summit which is a steam of about 19 hours.

August 9-10, 2017

The R/V Revelle departed from the dock in Newport, Oregon at 0900 on August 9th and headed out into the foggy, relatively calm seas off the coast of Oregon. Our first site was at 80 meters on the shelf called Endurance Shelf  where we were supposed to change out something called a BEP which is a Benthic Experiments Package. This package has a range of instruments on it that measures things like temperature, salinity, dissolved oxygen, pH and current velocity. Once on the bottom and plugged into the junction box, the data from these instruments are available real time via a high power, high band width cable back to shore.

The shallow water benthic packages are housed in trawl resistant frames to protect the instruments from fishing gear. The way we get these large packages on and off the bottom is by using a transport vehicle (ROV or remotely operated vehicle) called JasonJason requires a whole specialized team of people to get it in and out of the water, as well as to run and maintain it. The pilot is typically someone who would also be very good at video games, but needs to have incredible patience. The pilot, navigator and scientist run the deployment and recovery operation from a control van that looks something like NASA ground control. All of us students and educators stand a 4 hour watch in pairs in the control van documenting the events of each dive using both a text log and picture log. When you are in there it is like being in a space ship exploring another planet. I always wanted to be an astronaut – this is about as close as I will come –   being an Argonaut.

Julie Nelson, my watch buddy, and I were on watch in the van for the first dive. There was so much biological activity in the water column that it looked like marine snow. Finding the existing BEP on the bottom proved to be like looking for a polar bear in a snowstorm and we had to abort the dive without exchanging the gear. We tried once more, but the thick marine snow prevailed and we had to move onto the next site – Endurance Offshore at 600 m.  While I slept last evening, the night watch (the ship works 24 hours a day) exchanged the BEP at the Endurance Offshore site. The old one, that had been on the sea floor for a year, had some growth on it – a couple of the students found sea urchins on the frame – but it was pretty clean compared to the biological growth we have seen in the past on shallower instruments.

Today during my team’s watch in the control van, Jason was changing out some cables on the sea floor – we are still at the Endurance Offshore site – the pilot had put in the new cable and had just finished moving the old cable into a big basket to bring to the surface when we heard a loud “POP” and everything in the van went black. This was not good….. Jason had blown a power supply and the Jason team had to fix it, which took a while. In the meantime the science crew, led by Chief Scientist Deb Kelley, Orest Kawka and Skip Denny with assistance from a whole team of APL (UW Applied Physics Lab) engineers, as well as students, prepped and tested equipment to be deployed at sites later in the cruise.  One of the engineers even tested a drone, getting some good aerial footage of the ship (see the website for pictures).  The Jason crew finally got Jason fixed and we are now in the process of recovering the cable from the sea floor at the Endurance Offshore site and it is dark outside. Once all is on deck, we will head to the next site, Hydrate Ridge, located on the shelf slope off Oregon in 780 m of water.