April 15, 2012 Jumbo Piston Core
Speed 0.8 knots
Location Bransfield Strait (-62.56427333, -55.98799167)
Depth 253 meters
Yesterday we finished all scientific operations and we began our journey north back towards Chile. We are slowly maneuvering through lots and lots of ice and hopefully we'll make it back home on time. From the picture below you can see where we've been so far on this cruise. We are currently at the end of the red line headed back towards Chile. It'll take us a few days to get there, maybe more if the ice continues to be heavy.
Jumbo Piston Core
As I looked back over my blogs, I realized I hadn't shared one of the most interesting operations that the scientists have done. It's called a Jumbo Piston Core (JPC for short) and it is made of 24 meters of solid steel. The JPC is lowered over the side of the boat and dropped to the seafloor to collect sediment. It can only be used in areas that have a lot of sediment and not a lot of rocks otherwise it will bend. Because of the potential danger that can be caused by the wiring of the JPC, all of the outside decks have to be cleared. There are signs up on all the doors warning people not to pass through them.
The Jumbo Piston Core is slowly placed into the water on the side of the boat. A winch lowers the core until is about 50 meters off the bottom of the seafloor and then it is allowed to freefall into the sediment.
At the bottom of the core is a small device that stops the sediments from leaking out as the core comes up. Once it reaches the surface, it is raised back onto the deck using a crane. This JPC is full of mud and is so heavy the steel pipe is bending.
Once on deck, the inner core liner (PVC pipe) full of marine sediment is removed in pieces. It is pushed down from one end of the JPC and extruded on the opposite end. In order to get the tubes inside, at least two strong people must carry them.
Inside, they are labeled and stored in a cold room kept at 4°C. The tubes will be sent to a laboratory in Florida where the team will be able to look at them more closely. The geology team was able to complete a JPC yesterday that contained almost 80 feet of mud! The depth of these cores gives the scientists information that goes back much further into time than the other cores. This gives them more evidence into the history of an area and allows the scientists to tell a more complete story.