05 November 2011 | Gulf of Mexico
From Oct 20th through the 29th the Cape Hatteras partook on her second to last cruise of the year. Chief scientist Dr. Kevin Yeager led a team of muddy scientists on a search for petroleum hydrocarbons near the Deepwater Horizon site. In those 10 days they worked around the clock to sample from 30 stations. Each station consisted of a CTD cast to view the water profile and collect water samples followed by at least 2 deployments of the multicore for shallow sediment cores. Each core is placed on a pedestal that pushes the mud up through the top of the core sleeve so that it can be sectioned or cut at various heights to preserve and analyze later in the lab. Oil was seen and smelled in a few of the core recovered.
On the final day of the cruise we recovered a sediment trap that was deployed around the time of the oil spill. The sediment trap is similar to one the Hatteras deployed last summer in the Gulf. The trap has a wide mouth top that funnels down into a cup at the bottom catching debris as it falls to the sea floor. The cups at the bottom will rotate after a preset amount of time. Analyzing the different cups can tell you what was falling to the sea floor at various times of the year. As you may be able to see from the picture some of the cups contained large amounts of a black substance and some had smaller amounts of a brown material while others had matter that was a rusty color. It was interesting that some of the bottles beside each other didn’t look like they contained the same material.
The images from left to right show the multicore being brought back on deck with mud in the cores, cores hanging in the cold van ready to be extruded and sectioned, and the sediment trap on deck after recovery.