Ice Rafted Debris
By far, the best place on the ship to work is the aft control room. It offers eight large windows that look out over the water so you can watch the ice or keep your eye on the horizon when the seasickness starts to kick in. While it is a hub of activity when coring devices are being used (all the gears and controls on the left-hand side of the photo are used to operate the various winches that lower the empty corer down to the seafloor and haul the full corer back out again), often its only occupants are those who are looking for a quiet space to work, nap or watch whatever movies and TV shows they downloaded before the trip began.
I was in the aft control room, working away on yesterday's blog post, pausing occasionally to look out at the face of the Pine Island Glacier, when I noticed a dark blemish on an approaching iceberg. My first thought was, "Seal!" and I grabbed my camera and hurried out on deck to get a closer look. It was almost impossible to tell for sure, but it didn't quite look like a seal, so my second thought was, "Treasure chest!" and I hurried back inside to load the picture onto my computer and zoom in, wondering if "finders keepers" applied to things floating on the ice and how long it would take to deploy a zodiac to go and retrieve it.
Disappointingly, the object I saw would only be thought of as a treasure by a very small subset of the population (although a substantial number of people on this ship would consider themselves part of that subset). It is something called Ice Rafted Debris - small rocks and bits of sediment that get trapped in a glacier as it scours (or scrapes) the face of a continent, and are then carried off to sea by the chunk of ice into which they become frozen. When we take long cores of sediment from the bottom of the ocean, we often find pebbles buried many meters deep, and the explanation for them is that they were dropped by an iceberg floating above - former ice rafted debris that gets dumped when its raft melts. This piece was unusually large and it is hard to imagine where it came from and where it will end up. Eventually, the ice holding it will melt and this large boulder (or still, maybe, treasure chest) will sink to the bottom of the Amundsen Sea, likely never to be seen again. Fortunately, I got a decent picture to remember it by.