Going with the flow: Methane oxidation and fluid flow

Marie de Angelis, Ph.D.
Humboldt State University 

Wednesday, July 16, 2003
Pacific Forum – 3:00 p.m. 


Elevated methane oxidation rates are typically found in marine environments characterized by relatively high methane concentrations, including anoxic sediments, hydrothermal vent plumes, seeps, and hydrate fields. However, specific methane oxidation rates are not well correlated with methane concentrations in such environments, suggesting that other parameters control the rate at which methanotrophs can oxidize methane. 

Studies from two different methane seep sites—one associated with hydrates and one associated with tectonic activity—will be presented. These studies indicate that fluid flow characteristics that maximize exposure time of methanotrophs to elevated substrate levels may be a major control of methane oxidation rates within the water column, at the sediment/water interface, and within deep-sea sediments. Fluid flow in such environments may be affected by biological, geological, and physical processes—all of which can play a role in determining local specific methane oxidation rates.

Next: Geodesy in the service of marine geophysics