Gyre – We are a sediment sampling machine!

Here on the Gyre we really know how to party. We spent Friday night coring sediment only about 420 meters from the well head, right in among the drilling rigs, ROV boats, standby boats, and supply boats. (Quite the wild and crazy Friday night, right? We know!)

Captain Mike Harkreader, Chief Mate "Shorty", and Second Mate Kevin Phillips

Sampling in and among lots of other vessels can be a tricky operation for us because the Gyre is an older boat, meaning her crew members have fewer technological aids to utilize when it comes to navigating and especially steering her. For instance, most of the vessels out here are DP-enabled (dynamically positioned). Nevertheless, we are in the very capable and skilled hands of Captain Mike, Chief Mate Shorty (AKA Joe Perez), and Second Mate, Kevin Phillips. They are able to get us on-station with near-accuracy and hold us there long enough to take our samples. We were able to recover three multi-corer loads, totaling 47 cores. This is a fantastic haul.

Shorty holds the Gyre on our station while we collect sediment samples.

So far, the Gyre’s science team has taken over 230 full, core tubes from 21 locations. We’re pretty proud of those numbers. The cores we are taking near the well head appear pristine and undisturbed with very little oil if any, but they are chilly when they come up as it is only about 4 degree centigrade on the sea floor. The water in the cores is pumped off the top and filtered for bacterial population analysis by Lawrence Berkeley Laboratory, and bacteriophage research by Ecolyse. The cold, cold mud is extruded and carefully sectioned off for description and various chemical analyses. We have also frozen whole cores, still in their tubes. They will go to other laboratories for a variety of research and analysis.

Sea floor sediment sample

We also were able to deploy the underwater camera yesterday. A description and pictures of what we saw down in the deep, to come!

Pisces – Seep Mapping

In addition to CTDs, core sampling and camera-tow operations, another aspect of our mission includes the mapping of natural hydrocarbon seeps in the vicinity of the Deepwater Horizon site.

The Pisces was designed to be used as a fisheries research vessel, and was outfitted with acoustic gear that is used for finding schools of fish.  It uses sound, which refracts (or bends) when it passes between substances of different densities – such as between sea water and the air contained in the swim bladders of fish. Think of how a straw in a glass of water appears to bend at the water’s surface.  This is due to the refraction of light waves as they pass between the air and the water.  Sound waves work the same way.

This same equipment can also be used to find gases escaping from the sea floor.  We spent the morning over a plateau in the ocean, very close to Mississippi Canyon, where the oil spill occurred.  We made several passes back and forth over this plateau in a pattern that scientists sometimes call “mowing the lawn.”  Scientists can see the returns from the acoustic equipment on computer monitors, where the seeps show up as vertical lines of dots.

Later on, once we had surveyed the entire plateau, the scientists were able to put the data together to create a three dimensional map of the seeps.  Pretty cool, huh?

3D Seep Model

Meet the Gyre!

We’ve been really busy onboard the research vessel Gyre. Today we are sampling about 10 nautical miles northwest of the Deepwater Horizon well head in the Gulf of Mexico where our primary job is to take sediment samples using our 12-tube multi-corer. (So far we’ve had fantastic luck and have managed to pull up nearly 12 full cores every time!) In our onboard lab, we analyze the sediments to assess their toxicity (if any) and analyze sediments and water for the presence of oil or other contaminants. We also assess any bacterial response. This can help us learn how an increase of oil in the deep water environment may have affected the resident bacteria and other organisms.

The science team hard at work processing sediment samples

But, in addition to sediment, our team is also conducting CTD casts, gathering acoustic data, and even using an underwater camera to take deep water photographs of fish, crustaceans, and other sea life. (We’ll have more details about that project later.) In charge of our fine vessel is Captain Mike Harkreader and the research team is led by Chief Scientist Neil Summer of Ecolyse, Inc. Altogether there are 31 of us on board.

Tomorrow we have plans to deploy the underwater camera and collect more sediment samples. We are also in the process of building a gimbal table to stabilize our onboard standard analytical scale. Check back tomorrow for photos and more details about operations aboard the research vessel Gyre!

Ocean Veritas – Deep Sea Creatures and Muddy Sediment

There are days when pulling cores of mud out of the Gulf of Mexico and processing them might not seem all that thrilling. We, aboard the research vessel Ocean Veritas, heartily disagree.

Bringing in the multi-corer and a full carousel of sediment samples

Our Chief Scientist Ian Hartwell is very interested in an odd trend we’ve noticed the closer we sample to the well head: there is an ever-increasing layer of strange, fluffy, brown mud in our sediment cores. This is the opposite of what we think should be happening. Typically, as we sample deeper offshore, we would expect the soft, mud layer on the sea floor to decrease; it settles out as energy from the rivers dissipates. And, at first, this is what we were getting: as we sampled further from shore, the cores came up with less and less sediment because we were reaching the more compact clay layer under the mud more quickly and the cores could not sink down as deep.

Processing a sediment sample

But, at the last several stations, the fluffy mud layer grew, instead of decreased, as we got closer to the well head. There were no visible oil globules in the mud and we only saw a slight sheen in the cores at the actual well head site. Also, as opposed to the normal muddy layer, which is similar to pudding in consistency, this sediment was more loose with the first centimeter or so practically floating near the surface of the sample. It’s too soon to make any conclusions about what this means, but it is an interesting observation.

And then there are the strange and curious deep sea creatures that occasionally get collected along with the sediment. When we take our sediment samples, the multi-corer is lowered down very slowly by the winch. The apparatus settles gently on the sea floor (so that there is minimal disruption to the loose top layer of sediment) and then the tubes drop straight down into the mud. Each tube has a lid. When they close, anything directly above the mud will get caught if it doesn’t get out of the way fast enough. If the creatures are in one of the five cores that we use for chemistry analysis we just let the creatures go. We also let them go if they are clearly pelagic (meaning that they live in the water column).

Goby fish in sediment sample

See, never a dull moment when it comes to sea mud.

Welcome Research Vessels International Peace and Gyre

We welcome research vessels International Peace and Gyre who have recently joined the Ocean Veritas and the Pisces on sampling expeditions out in the Gulf of Mexico.

While at sea the team on the International Peace, headed by Lead Sampler Ken Cerrito of Exponent will conduct CTD and fluorometry casts, and take water and sediment samples.

The primary mission of the Gyre, led by Chief Scientist Neil Summer of Ecolyse Inc., is to collect sediment samples with a 12-tube multi-corer. But, the Gyre has a large science team aboard and there will be other research conducted while at sea such as CTD casts, and an interesting apparatus called a camera sled.

Check back often for exciting updates from both of these vessels.

Pisces – the Tow-Cam

Last night, we deployed a tow camera to take photos of the sea floor to look for any evidence of oil that may have settled there, and for hydrocarbon seeps. Ken Feldman, a contractor working for Woods Hole Oceanographic Institution, is in charge of the tow camera operations on this expedition. After we brought it back to the surface, he talked a little bit about the tow camera and how it works.

The camera is in a pressurized housing…It triggers a flash every time it takes a picture, which is important because there is very little light at the depths where we’re operating. We program the camera to ‘sleep’ for the 30-40 minutes while we lower it, using a winch, to the sea floor. Once the camera ‘wakes up’ on the bottom, we set it to take a picture every ten seconds. It has two altimeters – one that looks down, so we can see how far we are off the bottom, and a forward-looking one, so we can detect any obstacles in front of the camera and avoid running into them. We try to keep the camera about two meters off the bottom. During this process, we keep the ship moving forward slowly (at speeds of less than a knot) and take in or let out cable to keep it at the proper height above the sea floor. I’ve heard it compared it to flying a blimp through the Grand Canyon and lowering a refrigerator on a rope and trying to keep it five feet off the ground.

Crab seen by the tow camera

You see a lot of interesting stuff in the pictures. On this trip, we’ve seen fish, crabs, shrimp and other animals. In the six years I’ve been doing this work, I’ve seen an octopus attacking the arm of an ROV, and some amazing geological features in some volcanically active areas, among other things. It’s an interesting world down there.

Ocean Veritas – Sample Transfers and Fresh Supplies

So much for the slow day in-port the team was hoping for. We arrived at Port Fourchon, Louisiana around eight this morning and things have been very hectic ever since. Several members of the team went onshore to grab some personal things this morning, while the rest of us prepared sediment samples for transfer.

Michael Jessich of Entrex and a freshly cored sediment sample

Our samples are going to a variety of labs for processing. Most of our samples could stay onboard if we had the space for them, but the samples intended for further chemistry analysis such as tests for four specific PAHs (polycyclic aromatic hydrocarbons are compounds found in oil) known as BTEX (benzene, toluene, ethylbenzene, and xylene) need to be run within a week or two of sample collection. BTEX analysis is very important for measuring the presence of oil in the sediment.

After a morning of packing samples and waiting for supplies to come in, our groceries also came in, so we loaded boxes of fruits and vegetables, meat, and dozens of cases of soda, Gatorade, and water into the galley. Apparently Port Fourchon is quite the hub. Not only did we get moved to three different slips throughout the day, we watched boat after boat pass by like a Port Fourchon boat parade!

This evening our final supplies arrived, team members returned from various onshore errands, and the Ocean Veritas headed back out for open water.

Pisces – Now that you’ve got those cores, what are you going to do with them?

Another long day of coring… Still, J.P. found some time to show us what he does with the sediment samples he collects.

“Once we bring the multi-corer up, we remove the corers and let them settle for a bit.  Then, using a tape measure, we measure the amount of water and the amount of sediment, and take a sample of the water.  Next, we place the tube on a device that pushes the sediment up, forcing the water out of the top of the tube.  After that, we scoop and scrape the top inch or so (which is the part we’re most interested in for this expedition) into a jar, which we label and seal to be shipped to a lab onshore.  Then, we rinse the tubes out, put them back on the frame and we’re ready to go again.”

J.P. Walsh pushes the water out of a core sample

When the cores come up, you can see a few inches of brown, runny mud on top, and gray stuff on bottom.  The gray stuff, it turns out, is actually clay.  J.P. took a few samples of this clay to use for his own research.  He uses techniques such as radiocarbon dating to study properties of these deep-sea sediments.

Some of us, on the other hand, think this clay is kind of fun to play with.  It’s not every day that you see clay from 2,000 meters beneath the sea.

Later in the evening we deployed the tow camera again.  We’ll tell you more about it in a future post.

Ocean Veritas – Remembrance

We had a solid sampling day today; completing five stations and ending our day less than a mile from the well head. We started at over 800 meters deep and went to about 1500 meters so by the end of the day, at the well head, it took close to an hour-and-a-half for the corer to go down and come back up.

When we got to the well head, we took a moment of silence for the crew who were lost in the Deepwater Horizon explosion and reflected on why we were all out here. With only four or five other ships nearby, it was much less active at the well head than we thought it would be. There are two drilling rigs near the well head and their size is impressive. We could actually see them all day starting out as tiny spires and growing to almost look like cities in the water as we drew closer.

We didn’t finish sampling until late tonight and there is still some work to be done before we head to bed. In a word, we’re beat. Tomorrow we head back into port and we are hoping for a slower day as we refuel and restock.

Ocean Veritas – Meet the Chief Scientist

The Ocean Veritas is fortunate to have NOAA scientist Ian Hartwell aboard as chief scientist. With a background in fisheries and marine biology, and specific expertise in environmental toxicology, Hartwell is uniquely qualified for this position. As he puts it, “contaminant impacts on biological systems is what I do.”

Chief Scientist Ian Hartwell of NOAA

What does the chief scientist do and why is it important to have a chief scientist aboard?

I understand how the contaminants impact the biota and I’ve been out on enough cruises and enough different kinds of sampling endeavors, so I know how to organize the work and the team, improvise when things go wrong—which they invariably do—and keep them going. That’s what the chief scientist does; he keeps things going.

The Ocean Veritas is tasked with collecting sediment samples. Why is this important?

By analyzing sediment samples we can assess the magnitude and extent of oil contamination that may be present on the sea floor. We will be conducting a systematic survey of offshore transects, radiating out from the well head to various locations on shore that were heavily oiled. We’ll track the path of the oil to the shore to see how much of it may have sunk on the way. We’ll also be looking at other areas including convergent zones, burn areas, and aerial dispersant application areas, which may have caused the oil to settle to the bottom.

Working on a research vessel, there is grease and dirt all around you. How do you ensure that outside contaminants don’t get mixed in with your sample?

You’ll always see us out on the deck with gloves on. That’s not to protect us. It’s to protect the samples from us.

How do you take a sediment sample?

Before we get to each station, we prep all of our gear. We have to know where all of our sample jars, chemicals, and gloves are. We have to have our data sheets, jar labels, and location data ready. Then we put the gear over, and we wait. In the shallow areas, we don’t wait very long, but in the deep areas, where we let out 1200 meters of cable, it takes half an hour to go to the bottom and half an hour to come back up. The sample only takes a second. It hits the bottom, goes in, and is done.

Then when the apparatus comes back up you’ve got this little beehive of people around the sampler, doing things with it. We extrude the samples at specific water depths and then get them in the containers as quickly as possible and preserve them with a variety of preservation methods. Some will be frozen, some will have chemical preservatives, and some will just be refrigerated. A sample also goes to the chemists and they go off in their lab and start doing their analysis on it.

It sounds like you stay really busy. So, when does the chief scientist sleep?

Well, yeah, I don’t sleep much. I’m there for the end of the previous shift and I’m there at the beginning of the next shift as well, so I stay pretty busy.