Katrina Edwards is a geomicrobiologist who studies the microbiology of hydrothermal sulfides and the igneous ocean crust. She has particular fascination with one common, yet elusive microbial group associated with these deep habitats, the iron oxidizing bacteria. These are the bacteria that make rust. She received her Ph.D. in geomicrobiology from the University of Wisconsin, Madison, in 1999 and spent the following 7 years as a researcher at the Woods Hole Oceanographic Institution, Massachusetts, USA. This is where she "sunk to the bottom of the ocean" and never came back up. She is now a Professor of Biology and Earth Sciences at the University of Southern California, Los Angeles, and is the Director of the
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 seventh blog post. To track her research ship’s current position, click here. To see all her posts, see "60 Seconds in North Pond."
SOMEWHERE NEAR THE NORTH POND (February 26, 2009)—The transfer of the ship’s steward to a helicopter for safe transfer to a hospital went off without a hitch yesterday (see photo, left). The entire operation only took about 6 minutes, professionally executed and delivered, truly impressive. Kudos to Captain Bergmann for a job well done, to Dr. Miller for his care of Frank these past few days, and to the Fahrtleiter, Heiner Villinger, for his foresight and follow-through in pushing for the need to have a doctor on board this vessel — not a typical arrangement. All of the science party and ship crew wish Frank (and his thumb!) speedy recovery.
On with the show! We’ve been steaming back to North Pond. I am starting to feel like I have always been here, rocking back and forth in the middle of the big blue Atlantic. (Good news: The German research foundation granted Heiner’s request for additional days. We will be returning now March 13th, very tentatively, depending on return flight arrangements). We are settling into routine — of sorts, except for things like helicopter rescues. We are having daily science meetings to strategize and plan. We are starting a lecture series on topics relating to the deep biosphere and subseafloor ocean — the what’s and where’s of the intraterrestrials, how to best detect them, what we can learn from expeditions past.
We are collecting data — still. Oftentimes on ships, for many analyses you simply have to collect and process samples for analyses to be done back in the home laboratory. However, there is a lot of additional data collection and analysis that can be done shipboard — time permitting. Oxygen profiles, other chemical species that are very important for the deep biosphere like nitrate, carbon, activity measurements, and more.
Also, the geophysics crew has analyzed most of their data so far and have provided us all with a much clearer picture of the pond and the sediments. We have been spending an inordinate amount of time poring over maps, trying to figure out how thick the sediments are, and how heat and sediment distributions are related, if they are. Why is this important? Basically, it is so that we can really nail the experiments we want to do with the CORKs at North Pond (I explained them in a previous post).
When we wrote the proposal to the IODP, we had a pretty good idea of what we wanted to do, broadly speaking. We wanted to study the microbiology in the ocean aquifer (the ocean below the ocean) under varying conditions, especially where the water is coming in (something we know reasonably well, because that famous Hole 395A is sitting there) and where it is coming out.
That is the tricky part that has us scratching our heads about where to drill next. We can no longer do a detailed survey, because of the time lost from the accident the other day, and must come up with a more focused strategy. Which we think we are coming to, but… ever heard how the devil is in the details? It is that devil keeping me up at night now, and it’s one that relies on geophysics. More on that in my next post.
Photo courtesy USC/Katrina Edwards