IODP Exp. 382 Week 3: Our guest blog and a Southern Ocean connection

Michelle writes…

This week on Expedition Antarctica is a little different. Instead of writing a whole new post, I am going to direct readers to a recent guest blog that I wrote with Marlo Garnsworthy, outreach officer and artist extraordinaire! Marlo and her day-shift counterpart, Lee Stevens, make up a two-women super outreach team dedicated to sharing the science with the wider community. Head on over to the Exp. 382 blog page to read what they have to say.

Without spoiling too much, I will say that my guest blog reflects on our encounters with wildlife, a shared interest in polar waters, and the importance of taking time to appreciate the beauty in the science. Click here to read more about a Southern Ocean Connection.

We’re now at the Dove Basin, in the Scotia Sea. Cores are coming steadily up from more than 3000 m (!!) and the science team is ready to get their hands back on some sediment. We’ll be here awhile (~10 days), so check back soon to find out more.

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IODP Exp. 382 Week 2: Our first cores and the chaos that ensued

Michelle writes…

I have been lucky enough in my graduate career to have traveled to Antarctica twice and  logged ~60 total days at sea. All of my previous ocean-going research experience has been with the U.S. Antarctic Program (USAP) aboard the R/V L.M. Gould and RV/IB N. B. Palmer. Sailing as a new IODP science party member, I can’t help but compare my experiences on the JOIDES Resolution to those with the USAP.

The main thing that stands out as different is the pace of the work. The working day on USAP vessels and the JR are the same: two shifts running 12 hours each, starting either at noon or midnight. This schedule maximizes the work that the science party can do with the available ship time. I began mentally preparing myself for 12-hour shifts before the cruise, but didn’t dwell on it too much. I had done this before. It would be fine… famous last words.

My advisor, Amelia Shevenell, and labmate, Imogen Browne, both previously sailed on the JR and told me how busy it was going to be. I believed them, but I didn’t fully appreciate their words of wisdom until I stepped into the core lab for my very first shift. Admittedly, the first day at our first site started out slow because we had to wait for the sediment cores to equilibrate. The cores at the first site were coming up from ~650 m below sea level, plus an additional ten to hundreds of meters below the seafloor, so they are quite a bit colder than the 20°C core lab temperature. After the cores equilibrate to room temperature, the Physical Properties team runs them through a series of multi-sensor logging instruments to measure various physical parameters. These include magnetic susceptibility (a proxy for the relative amount of terrestrial material), thermal conductivity (to help determine chemical composition, porosity, structure, and fabric of the sediment), and natural gamma radiation (to aid in identifying clay composition). These measurements, which we make on whole round (un-split) cores, require about 45 minutes per 10 m core. Although I am part of the Physical Properties lab, my main responsibility for the time being is to take individual samples to measure moisture and density (MAD), which happens after the cores are split. So I had a little down time that first shift, before things got crazy.

Scientists Lara Perez, Lisa Tauxe, Stefanie Brachfeld, and Anna Glueder take some time to inspect a newly split core. Photo credit: Marlo Garnsworthy

 

 

 

 

 

 

 

 

 

 

Boy, did things get crazy! The next half of the shift was a steady (and frequently chaotic) interval of taking samples for moisture and density, weighing them, and placing them in the oven to dry for 24 hours. It seemed like the work never ended. Night shift finished their time in the lab, briefed the day shifters, and we went to bed, and then returned to an even busier shift 12 hours later. Cores kept coming up, other cores kept being split, working halves for sampling made their way to the sampling table, archive halves went to the sedimentology team for core description. Over, and over, and over again. I am not exaggerating when I say I spent maybe 30 minutes sitting down during that second 12-hour shift.

The sampling table is where I live now. Photo credit: Marlo Garnsworthy

 

 

 

 

 

 

 

 

 

 

Shifts are not always so fast-paced, but I wanted to share this story so that readers get a sense of the scale of an IODP operation. The JR is essentially a floating island of laboratories with a drill rig attached, outfitted with more instruments and equipment than I can normally access in any given day on land. These capabilities allow an international team of scientists from different subspecialities to collect and process tons of data, all at the same time. I find it absolutely amazing that we are out here at all, let alone imaging sediment with an X-ray machine, identifying reversals in Earth’s magnetic field, or continuously providing age constraints using microscopic fossils preserved in the sediment. I hope whoever is reading this also finds this amazing and checks back periodically to learn more about the expedition over the next two months.

We’ve just left the Falkland/Malvinas sites and we’re heading south! Keep your eyes and ears open for more news about science, sediment, and sailing through the Southern Ocean.

 

IODP Expedition 382 Week 1: Our foray into Iceberg Alley and Subantarctic Ice and Ocean Dynamics

D2iDJ47X0AEEEq6.jpgMichelle writes…

The apparatus that the JR uses to drill sediment cores. The rig is 60 m high and will support our efforts to drill up to 600 m of sediment in ~3500 m of water

Well the Shevenell Lab is back at it again, this time in the Scotia Sea! If you had the opportunity to read about Imogen’s time in the Ross Sea aboard the JOIDES Resolution (JR), then you might already know about the International Ocean Discovery Program (IODP) and the work that scientists and crew do on the JR. For those who are unfamiliar with IODP, I have included some background in this blog post. IODP is committed to reconstructing Earth’s history through the collection and investigation of sea floor sediments and rocks. Scientists and organizations from member countries participate in the shore- and ship-based science. Some countries and consortiums also provide the platforms on which scientists sail. This includes the JR, which is operated by the United States. To sail aboard these vessels and take advantage of deep sea drilling capabilities, scientists must submit proposals to drill. The proposal process can take years or even decades (literal decades!) and often includes multiple revisions. Proposed projects that pass review then move to the planning and staffing stage. Scientists from all over the world are staffed to sail with IODP. On this cruise, Expedition 382, we have scientists from, and representing institutions in, the U.S., the U.K., Germany, Korea, Japan, Norway, China, Australia, Brazil, the Netherlands, India, and Spain. This means that at any one time I often hear about four languages spoken at once in the conference room!

Our goal for Expedition 382, as an international team, is to uncover how Antarctica has changed over the past 14 million years, including how ice sheets responded to atmospheric CO2 changes, how ice sheets affected global sea level, and how the oceanography surrounding Antarctica evolved. To do this, the JR will be traveling to a site directly south of the Falklands/Malvinas, as well as to two sites in the Scotia Sea, which is located within the stretch of ocean between South America and the Antarctic Peninsula. The Scotia Sea sites were chosen because they are in the pathway of an iceberg armada. Dubbed Iceberg Alley, this stretch of ocean is the terminus of the counter clockwise-flowing Antarctic Coastal Current that transports icebergs around the continent. Once they leave the frigid waters of their icy birthplace and enter the relatively warm sub-Antarctic waters north of ~60°S, the icebergs melt and deposit debris that they have carried since they were glaciers sitting on the continent. The debris is a clue to how Antarctica evolved through time.

This figure shows the sites we will drill during the two month expedition.

Our co-chiefs, Michael (Mike) Weber and Maureen (Mo) Raymo, and lead-proponent, Victoria (Vicky) Peck, are anticipating hundreds of meters sediment that we can use to understand major changes in Antarctic history. Expedition 382 scientists are eager to collect the entire 14 million year sequence, but we are particularly interested in sediment that captures times of change in Antarctica. Many of our individual proposals focus on the glacial intensification throughout Antarctica at different times in its history, or times that represent higher-than-modern global temperature and CO2. Investigating these changes is very important for understanding the rapid retreat and thinning that we currently observe in Antarctic marine-terminating glacier systems. To better predict the response of modern glaciers to environmental stressors, we look to the past to understand ice-ocean-atmosphere dynamics. Our questions address various themes, such as ocean temperature, water mass distribution, and carbon cycling.

A presentation delivered by Co-chief Scientist, Mo Raymo, explaining the importance of understanding Antarctica’s past climate

So that’s an overview of who we are, what we’re doing, and how we plan to achieve our science objectives. We’ve had a bit of delay leaving port and now leaving the fueling station, but we should be on our way soon. Stay tuned for updates as we transit south.

3/1/2014 – Everything Antarctica

Michelle writes:

The past week has been full of quintessential Antarctic experiences. I want to highlight these in the blog today because I actually spend a lot of time in the lab rather than outside on deck, so these experiences have been very special.

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1. Penguins: we got up close to a pair of Emperor penguins the other day as a large piece of sea ice floated by. They stood by watching the boat, craning their necks every so often like they were trying to get a better look at the giant, orange thing in front of them. My favorite thing about Emperor penguins is how they walk: it’s a slow shuffle as they move an entire side of their body in one motion. By contrast, I always see the little Adelie penguins run in spurts. They usually hold their wings out behind them and run so far forward it looks like they are going to trip over their little feet.

1-emperor-1 2. Blizzards: Antarctic storms are world-renowned as ferocious white-outs with howling winds and temperatures many tens of degrees below 0°C. We have hit a few storms throughout our cruise, but a couple days ago, we stepped out on deck to flying snow that stung our faces and temperatures so cold we could only stand to be outside for a few minutes. Some sea ice was piled higher than the back deck and I couldn’t see more than about 50 yards in any direction. This particular storm was located north of the ship, but it had pushed much of the sea ice south toward us. We are still trying to break through into open water. It’s slow going, but the captain and mates are working hard to get us through and ship speed should pick up soon. Continue reading

2/23/2014 – Palmer Fever

Michelle writes:

I have never been affected by island fever. When I was going to school in Hawaii, people used to ask me, “Don’t you get island fever?” when I got back from a semester at UH-Hilo. “No, although sometimes I do get Hilo fever,” I would respond, referring to the fact that it was hard for me to get out of Hilo due to school, work, and no car. I understand why people would feel trapped on an island but it just never phased me.

What could be more fun than recovering Eocene/Oligocene boundary rocks?

What could be more fun than recovering Eocene/Oligocene boundary rocks?

I think about that question now that I have been on a ship for close to a month. I guess one would call it Palmer Fever. And the answer is “No, I don’t get Palmer Fever.” I think the reason is we stay busy everyday. The last two days have been up-on-your-feet-for-12-hours kind of days. By the end, everyone is pretty exhausted. However, there are slow days and we have free time when we come off shift. So what do we do? We have found fun and quirky ways to keep busy, on and off shift.

While passing time on a slow shift, most people read, write papers, or help another group with their sampling. Occasionally, someone will post a crossword and passers-by will stop to fill out a word or phrase on their way between jobs. For the students, downtime during shift is a perfect time to write a blog, check email, or peruse papers that our PIs have assigned.

During our time off, there are a surprising number of activities to keep a person busy:

Game Face status: on

Game Face status: on

The natural evolution of the Seasickness Competition

The natural evolution of the Seasickness Competition

  • Sleeping: we are usually falling over by 3AM after a noon to midnight shift (for the day shifters). This counts as fun for a bunch of students.
  • Cornhole tournament: there has been a fair amount of smack-talk and off-hours practicing as people are starting to get competitive.
  • Movie night: each night after a day shift, a couple of the ship’s mates host a movie in the lounge, which they call Action Theater. Action Theater usually involves comedies/action flicks and high-tech Nerf guns.
  • Working out: In addition to individual workouts, we have a sign up sheet for pushups/sit ups. Every time an instrument goes into or comes out of the water, you have to do however many pushups/sit ups you signed up for. I signed up for 10 push ups, so if a core is deployed I have to do 20: 10 for in the water, 10 for out of the water. I think I have done about 450 pushups, with about 100 to catch up on.
  • Galley socializing: On a busy day, like today, dinner is a short affair. However, after shift is done, a group will often spend 45 minutes in the galley just hanging out and chatting.

We also love to celebrate: Continue reading

2/15/2014 – Playing in the Mud

(and the Grease, and the Salt Water)

Michelle writes:

1-IMG_7135The past week has been a busy one. We have secured 3 full kasten cores, 1 jumbo gravity core and 1 jumbo piston core (with 1 accompanying trigger core). A kasten core has a rectangular barrel that is deployed via gravity. It penetrates 2-3 meters into the sediment and can be opened on the ship so we can describe the stratigraphy, take photos, and collect samples. Each kasten core takes about 12 hours to process, depending on the length. First Gene has to describe the core (color, layers, sediment composition), then Tasha will take pictures. After that, someone on shift puts on the lab coat and nitrile gloves and takes samples for DNA/RNA.

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The next round of sampling includes taking sediment for organic geochemical analysis and foraminifer microfossils (fossils of calcareous single-celled animals). These samples will be used for a suite of geochemical analyses to determine past temperature, productivity, and oxygen content, among other things. While geochem and foram sampling are happening on one side of the core, another person is sampling for physical properties on the other side. If there is enough mud left, we will also take pea-size samples for diatom analysis and 5-cm interval samples for radiocarbon. Believe it or not, the first layer of sampling on a 2-3 m core takes 7-8 hours with planning, putting together the core barrel, sampling, cleaning sponges and utensils, labeling bags, and sample storage/inventory. These are the days when the marine geology group spends 12 hours on their feet. Continue reading

2/10/2014 – Entering Totten

Michelle writes:

1-P1010313We are just about 6 nautical miles from the edge of the Totten ice band and should be able to break through the sea ice into some ice-free water adjacent to the coast by this evening. Our watch shifts now demand a higher level of attention because we are in un-chartered waters; there is no pre-existing data from this area. Every seafloor feature that shows up on the screen on the Knudsen bathymetric profiler has never been seen before. NBP14-02 will be the first cruise to survey the seafloor and collect geological and physical measurements of the sediment and ocean currents.

Now, all planning is in overdrive. At the transition between shifts, there is usually a PI meeting at the navigation table or in the Chief Scientist’s room. These meetings include deciding which sites to hit first, which group will run their instruments and in what order. As we steam toward Totten Glacier, the researchers running the seismic instruments are planning their lines (the distance between two waypoints on which they will make their measurements).

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These images are very important because they will be high-resolution images of the ocean bottom and the sub-bottom down to about 400 m. That is tens of millions of years of a sediment record in one picture. The seismic images show the various layers and points of contact between geologic periods. For example, we may be able to see the boundary between the Eocene and Oligocene. Continue reading