Yesterday was a long but good day. We reached our first coring station after 12 hours transit from the previous station. After arriving at the station, we started to survey the area using an instrument which uses sound waves to test the condition and nature of the mud that is at the bottom of the ocean. The goal is to find a location where mud is thick, relatively undisturbed, and would more or less represent a structure similar to a layered cake. It took about a couple of hours to find a suitable spot where we could try to deploy a jumbo piston core with the hope of acquiring long sediment cores. While the detailed mechanism of how it works is quite complicated, this coring device primarily consists of a long hollow pipe with a heavy weight at the top and is lowered to the bottom using a wire or rope. The heavy weight at the top would facilitate digging deep into the mud and fill up the pipe with sediment, which can then be pulled out and brought back to the ship. Using the layered cake analogy, you can think of this operation as putting a straw through a cake. Deploying any instrument, small or large, by the side of the boat is an onerous job. So, much of the day was spent setting up the coring device, sending it down to the ocean bottom, and getting it back on deck. Happy to report that we recovered a nice sediment core. It was almost sunset when the core was back on deck and we were just getting started. We had two more things to do before we could leave the station. One was to collect small cores using another coring device called ‘multicore’ and collect water using CTD. By the time the CTD operation was done and we finished sampling, it was close to midnight and we were ready for bed. By the way, I almost forgot to mention about Styrofoam cups. It has been a longstanding tradition to color Styrofoam cups and send those in a laundry bag(!) tied to a deploying instrument. As the cups go down to the bottom of the ocean, the weight of the water squeezes all air from these cups, and makes them small without distorting the aspect ratio. So you get a miniature Styrofoam cup. These miniature cups make great souvenirs. Next time your oceanographer friend is out on an expedition, don't forget to ask if she/he would be kind enough to bring back a Styrofoam cup for you :).
Sue Holt
11/14/2018 02:20:35 pm
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AuthorChemical oceanographer, Paleoceanographer, Chef-in-my-kitchen.......not necessarily in that order. Archives
December 2018
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