So yesterday we were able to visit a specific brine pool called Jacuzzi of Despair. The name was given because of the many organisms that die going into the brine pool. These bodies of water within the ocean are formed by salt tectonics. During the Jurassic period the shallow waters of the Gulf of Mexico caused water to evaporate and form a large layer of salt. As sea level increased sediment began to overlay on top of this thick layer causing some movement. The salt layer penetrated through the sediment creating hypersaline domes. The salinity in brine pools is ~4-5 times higher than average salinity of seawater making it denser forming puddles or even lakes on the seafloor. Methane bubbles are often found at the surface of brine pools.
During yesterday’s dives we were able to see a couple of dead crabs and isopods in the brine pool. After about an hour or two at the site, the vessel began to drift causing a delay in operations. There was not much activity during my watch since it was at the same time the vessel drifted. Once we were back at the target site, Hercules was prepared for mapping of the brine pool using mutlibeam sonar lead by one of the PhD students on board. After mapping, Hercules also tested new equipment prepared by scientists from Woods Hole Oceanographic Institute. Scientists were testing a laser spectrometer, and newly constructed reel with an attached CTD. The laser spectrometer was used to take in situ measurements of the gases formed in the brine pool. The CTD was used to create salinity, depth, and temperature profile within the brine pool. Mussel samples surrounding the brine pool were also collected at this site.
Once the ROVs were back on board samples were removed and taken to the wet lab, which is where I helped process mussels. After processing about 13 mussels I began to feel seasick, and had to take a small break. Fortunately, I was able to recover and finish the rest of the samples.
Stay tuned for the next dive at www.nautiluslive.org!
Photo Copyright: Ocean Exploration Trust