Editor's Note: University of Southern California geobiologist Katrina Edwards is taking part in a three-week drilling project at the Atlantic's North Pond—a sediment-filled valley on the ocean floor—designed to locate and study what she calls the “intraterrestrials”: the myriad microbial life-forms living inside Earth's crust. This is her fourteenth blog post. To track her research ship's current position, click here. To see all her posts, see "60 Seconds in North Pond."

SOMEWHERE ABOVE THE NORTH POND (March 5, 2009)—I sit covered in mud. Changing clothes has begun to appear futile—fresh clothes appear to stay so about 15 minutes. I should have brought a jumpsuit to wear like those the deck crew members use. None of the science people wear jumpsuits—we just get grubby.

Well, that is not entirely true if you have caught any images of our chemistry team—the three musketeers, Wiebke Ziebis, Tim Ferdelman and Jim McManus—in the cold room. That team does indeed wear thermal suits, which help, but they still get cold. But perhaps not as muddy!

When we bring new cores on deck, the first thing we do is to measure off one-meter (three-foot) sections, label them and cut them.

We then bring them into the cold room—which is maintained at 4 degrees Celsius (39 degrees Fahrenheit), same as a refrigerator, and as the ocean water at that depth. All this must be done as soon as possible, so there is a lot of hustling going on. Careful hustling, mind you, as mishandling precious core is a big no-no. But we have to get the core cold again, quick for the chemical measurements to be made, since it warmed up on the way up to the surface, and on deck.

Once the core is chilled, the three musketeers get to work: They cut tiny windows into the side of the core liner in order to put sensors into the center of the core to make some of the measurements, like oxygen (one of Wiebke's specialties), and then insert tiny tubes to suck out fluids that are in the pore spaces in the sands and clays. As you might imagine, this takes a very long time, and it is no fun to be at 4 degrees C for hours and hours on end.

After the chemists are done with their measurements for one particular core, which can be three to seven sections (or more, when we have used the 12-meter [39-foot] core barrel), we take each of them sequentially for sampling. We first split the liner down each side, cut the ends, and then split it open for sampling. One half goes to the core archive and the other half we work with.

Each lab has certain sample types they are interested in, and a certain frequency and sample volume they need. There is often some horse trading to make sure we have a reasonable distribution for all of our projects. It is important to get as much science out of a core as possible. Once one core is done, it's on to the next, and so on. Then there are often "treatments" that need to be done on fresh samples, like applying preservatives.

One of the things I really love about going to sea is getting to work with my hands [as well as] getting back in the lab. As a professor, I don't get to do that nearly as much as I did earlier in my career. Teaching, supervision of students and postdocs, serving on committees, and other obligations keep me from the lab much of the time these days.

But when I go to sea, I am there to work. You do what needs to be done, when it needs doing—seagoing science parties require a lot of teamwork in general. I have to say that I have never worked with a group as talented, hardworking and amicable as this one.

Though today is our last coring day, it is not our last working day—we'll be busy until we hit Dakar, Senegal. I look forward to my last week with this group of scientists and know that when I go home I am going to genuinely miss them, and miss this atmosphere.

We have just a few hours of science time left, so we spend it doing a few "cleanup" multibeam data lines* to make even better maps. At 7 P.M. local time—promptly (Germans are more punctual than Americans, I've learned)—we will depart for Dakar and we will celebrate the end of our days above the North Pond with a toast to the captain and crew in our favorite gathering spot—the hangar where we also have our core-splitting parties.

Correction (posted March 18, 2009): As Edwards notes in her next post (citing "fried brain!"), she was working with multibeam data, not seismics. The sentence marked with an asterisk has been changed.

Photos of Edwards and others working on samples in the ship's cold room, courtesy Katrina Edwards/USC