Text and photos: Simone Sauer
Last week was great on the RV Kronprins Haakon. We got a lot of pore water and delicious cinnamon rolls. Unfortunately, these things have nothing to do with each other. Cake is served every day on the boat which is very tempting, and yesterday no one could resist the cinnamon rolls.
As for the pore water, all the previous days we have been preparing very thoroughly setting up rack and vials, numbering them, and then waiting impatiently for them to be filled.
On superstation 2 we then got our first gravity core for pore water sampling. As you can see on the picture, we only need tiny holes in the liner to be able to extract the water. The so called rhizons are inserted into the sediment and a syringe attached. After a few hours of waiting time the syringes are filled with beautiful clear (filtered) pore water.
After that the real work starts: the water has to be divided in numerous vials (picture) of different shapes and colors for analyses when we are back on land where we want to determine what kind of chemical components are dissolved in the pore water and how their concentrations change with depth.
This is very exciting as there is a lot of information that can be derived from these measurements. For example: Is there a lot of methane gas in the sediment? Are there horizons where carbonate minerals are formed? Are there horizons where some sediment components are dissolving? And how could these processes affect the sediment properties after they are deposited.