Carbonate Chemistry Dynamics in an Area of Active Gas Seepage: the Hudson Canyon, US Atlantic Margin

Wednesday, 16 December 2015
Poster Hall (Moscone South)
Fenix Garcia-Tigreros Kodovska1, John D Kessler1, Mihai Leonte1, Alexandre Chepigin1, Matthias Y Kellermann2, Eleanor C Arrington2 and David L Valentine2, (1)University of Rochester, Rochester, NY, United States, (2)University of California Santa Barbara, Santa Barbara, CA, United States
The fate of oceanic methane and its impact on the global climate has been of particular interest to the global community. The potential for vast amounts of methane to be emitted from the seafloor into the atmosphere due to gas hydrate decomposition has been under scientific evaluation. However, despite the great extent of these geological reservoirs, much of the methane released from the seafloor in deep ocean environments does not reach the atmosphere. Once dissolved in ocean water, the emitted methane can be microbially converted to either carbon dioxide or assimilated to biomass. Here, we will present results from a research cruise to the Hudson Canyon, northern US Atlantic Margin, where we investigated changes in ocean water carbonate chemistry induced by the oxidation of methane released from gas seeps. We will be presenting high precision pH data as well as methane and DIC concentrations, natural stable isotopes, and methane oxidation rates collected inside and adjacent to the Hudson Canyon in the summer of 2014.