Author: Eleanor Duva

Station 6 was east of Greenland and we arrived on Saturday the 13^th and started coring on Sunday. One of those cores caught a piece of a sponge! We also were visited by a large pod of pilot whales on Sunday. There was a group of roughly 20 whales that were jumping and diving near the boat, and another group closer to the horizon.

Monday was a big day of coring and by Tuesday evening, we had finished the CTD cast and were headed onward towards station 7, our last station!

Usually transit days are more relaxed, but Wednesday and Thursday brought some excitement. First, we released our last Argo float on Wednesday, followed by an XBT probe to get water column temperature data from the location of deployment. XBT stands for Expendable Bathythermograph; “expendable” because the probe is launched into the water and not recovered. The probe is a small, torpedo shaped object that stays connected to the launching device by a delicate thread of copper wire which transmits the data back to the ship. Once we reach its maximum depth, you break the thin wire and are left with a temperature profile of the water column the probe fell through. XBTs are used on the Langseth for seismic, in which sound is used to map the ocean floor, and an XBT helps find the speed of sound through water, which is dependent on the salinity and temperature of the water.

A few hours later, we experienced some disruptions in power as one of the main engines had a kerfuffle. At this time, I was in the bridge and it was interesting to see how the captain and second mate managed the situation. After some troubleshooting, the engineering team were able to get everything back online.

On Thursday morning, we were notified by the Icelandic Coast Guard that we were the closest vessel to a sailing vessel in distress and asked to render aid. The sailboat lost its sails in a storm and was running out of fuel. We backtracked for a few hours until we were in sight of the sailboat. The second mate, third mate, and one AB went in the fast rescue boat to bring them jugs of fuel. It was a little unnerving to watch the little orange boat be rocked around in the cold waves, but they reached the sailboat safely twice to bring them about 50 gallons of fuel. The rest of the deck crew contributed to a successful deployment and recovery of the fast rescue boat.

Our excitement for Friday was crossing the Arctic Circle!! And it was Larkin’s (our awesome videographer/photographer/science communicator on board) birthday! We also had a meeting for planning demobilization once we reach port, which includes arranging for shipping containers, cranes, and forklifts.

We are expecting some big seas in the next few days and hopeful we still be able to find a weather window to get station 7 done before heading to Reykjavik. Home stretch!

Pod of pilot whales, photo by Lexi!

View from the bridge as the orange fast rescue boat crosses our bow.

Fast rescue boat just after it was deployed from its davit on port side.

We started week 5 by arriving to station 5, located in the central Labrador Sea between Greenland and Labrador. We sent multi-core casts all day on Monday and Tuesday, and finished up station 5 with a CTD cast on Wednesday. Sunset is getting later as we continue northward.

Scores of northern fulmars and gulls kept us company at station 5, floating and flying near the ship. Fulmars spend almost all their days at sea, so they are not typically seen from land. Another lift to ship morale were two incredible nights of having Haagen Dazs ice cream bars for dessert.

During transit on Thursday, a group of us got a tour of the engine room. We saw the massive air compressors for seismic work, as well as the engines, shaft generators, aux generator, and air conditioning systems. In addition to catching up on projects and reading, I spent some time in the bridge while transiting.

By Saturday we were on station at station 6, east of Greenland. We resumed sample collection in about 2600 meters of water.

The multicore has two cameras on it, one of which is helpful for landing the corer on the seafloor and the other for troubleshooting sampling. One of the cameras we can view images from during the cast via the winch’s sea cable. Mounted near this camera is a light which we have the ability to turn off and on during the cast. The light is kept off for most of the cast, because it draws the most power and we don’t want to drain the batteries. All of the power for the cameras and light come from two batteries mounted to the frame of the corer, which get charged up overnight with a trickle charger. The second camera records the whole cast (which is mostly darkness) because it is a GoPro in a special metal housing. So we start the video recording then pack the GoPronto the housing and mount it on the multicore frame. The housing also has a highly specialized lens that corrects for distortion from the water.

Screenshot of a video from GoPro of a bottom landing

Techs attaching the GoPro camera inside its housing to multicore frame

Multi-core being recovered. Orange boxes on sides are batteries to power camera and light. Small white birds in background are fulmars

Week Four: 6/30-7/6

With our first three (00, 01, and 02) stations in the rearview, we started week four in transit to station 03 at Orphan Knoll, a feature of the ocean floor about 320nm off the coast of northern Newfoundland.

On Tuesday, we arrived to the site. The first core cast came up with 6 usable cores! Yay! However, by the time the second cast hit the deck, the science team has determined the structure of this sediment was not suitable for their project. It was too coarse-grained, which means it is advective sediment that water flows through rather than getting trapped in. Also, trying to centrifuge the water out of it doesn’t work as well.

We started steaming again and started fresh on Wednesday morning, now calling this site 4, just a little east of station 3/Orphan Knoll. The water is deeper here, which means more wire time and longer days, but hopefully better mud.

Wednesday and Thursday we cranked out four casts per day, pulling 5 or 6 cores off each of them. This sediment contained rocks! Which is exciting, if you like rocks. The rocks are all a sooty black color, until you crack one open to reveal granite or dolomite. This dark outer coating is manganese oxide. Dolomite is a very common bedrock where I live, so I got a nerdy little thrill out of holding pieces of it that we had pulled up through 4000 meters of seawater.

On Friday, we had collected enough mud after cast three of the day, yay! This site was our second of three designated places to deploy an Argo, so we sent that off the stern as we headed out. At first, the Argo laid flat in the water, but within a few seconds, it “came alive”, righted itself, and immediately began a “dive” to 2000m.

In the evening, we spent some time tracing wires and troubleshooting because our echosounder isn’t receiving data properly from the GPS. Then, we played some MarioKart. The following days in transit went similarly; projects and troubleshooting anything acting up, then MarioKart. On Monday we expect to be on station and coring.