Compositional changes in natural gas bubble plumes: observations from the Coal Oil Point marine hydrocarbon seep field
نویسندگان
چکیده
Detailed measurements of bubble composition, dissolved gas concentrations, and plume dynamics were conducted during a 9-month period at a very intense, shallow (22-m water depth) marine hydrocarbon seep in the Santa Barbara Channel, California. Methane, carbon dioxide, and heavier hydrocarbons were lost from rising seep bubbles, while nitrogen and oxygen were gained. Within the rising seawater bubble plume, dissolved methane concentrations were more than 4 orders of magnitude greater than atmospheric equilibrium concentrations. Strong upwelling flows were observed and bubble-rise times were 40 s, demonstrating the rapid exchange of gases within the bubble plume.
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