Close-up of methane hydrate observed at a depth of 1,055 meters, near where bubble plumes were detected in previous sonar data. Methane hydrates, a hydrate patch, and chemosynthetic communities were seen during today’s dive, but no active seepage was observed. Image courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013. Download larger version (jpg, 1.4 MB).
Dive 03 of the expedition was conducted at "New England Seep 3" in approximately 1,100 meters of water. Video courtesy of the NOAA Office of Ocean Exploration and Research, Northeast U.S. Canyons Expedition 2013. Download video (mp4, 58.8 MB).
The third remotely operated vehicle (ROV) dive of the expedition was conducted today at "New England Seep 3" in approximately 1,100 meters of water. The goal of the dive was to investigate four potential seep sites that were identified based on bubble plumes seen in multibeam sonar data during 2012 Okeanos Explorer mapping operations. ROV Deep Discoverer arrived at the seafloor in an area where the surrounding sediment was mostly silt and silty clays. We moved slightly upslope to the northwest, coming across stained sediment and white sediment (indicative of bacterial mats), along with varying patches of dead mussel shells, shell fragments, and carbonate rubble. Moving further upslope to the Northeast, we encountered carbonate in a line, like a small outcrop ledge associated with dead mussel shells. Turning back to the Northwest, we again encountered more carbonate material; mussels in small clumps; as well as several white, bacterial mats. Methane hydrates were observed at a depth of 1,124 meters, and as we continued upslope, we encountered a medium-sized mussel bed at 1,065 meters, confirming an active chemosynthetic community in this area. Further upslope, we found additional methane hydrates and a hydrate patch at a depth of 1,054 meters in the vicinity of the bubble plumes identified in previous sonar data, although no active seepage was observed during the dive. Common fauna observed along the dive track included an abundance of cutthroat eels, red crabs, eelpout, witch flounder and xenophyophores.